--[[
                NPaintPro
                By NitrogenFingers
]]--
 
--The screen size
local w,h = term.getSize()
--Whether or not the program is currently waiting on user input
local inMenu = false
--Whether or not a drop down menu is active
local inDropDown = false
--Whether or not animation tools are enabled (use -a to turn them on)
local animated = false
--Whether or not the text tools are enabled (use -t to turn them on)
local textual = false
--Whether or not "blueprint" display mode is on
local blueprint = false
--Whether or not the "layer" display is on
local layerDisplay = false
--Whether or not the interface is presently hidden
local interfaceHidden = false
--Whether or not the "direction" display is on
local printDirection = false
--The tool/mode npaintpro is currently in. Default is "paint"
--For a list of modes, check out the help file
local state = "paint"
--Whether or not the program is presently running
local isRunning = true
--The rednet address of the 3D printer, if one has been attached
local printer = nil
 
--The list of every frame, containing every image in the picture/animation
--Note: nfp files always have the picture at frame 1
local frames = { }
--How many frames are currently in the given animation.
local frameCount = 1
--The Colour Picker column
local column = {}
--The offset of visible colours in the picker column, if the screen cannot fit all 16
local columnoffset = 0
--The currently selected left and right colours
local lSel,rSel = colours.white,nil
--The amount of scrolling on the X and Y axis
local sx,sy = 0,0
--The alpha channel colour
--Change this to change default canvas colour
local alphaC = colours.black
--The currently selected frame. Default is 1
local sFrame = 1
--The contents of the image buffer- contains contents, width and height
local buffer = nil
--The position, width and height of the selection rectangle
local selectrect = nil
 
--Whether or not text tools are enabled for this document
local textEnabled = false
--The X and Y positions of the text cursor
local textCurX, textCurY = 1,1
 
--The currently calculated required materials
local requiredMaterials = {}
--Whether or not required materials are being displayed in the pallette
local requirementsDisplayed = false
--A list of the rednet ID's all in-range printers located
local printerList = { }
--A list of the names of all in-range printers located. Same as the printerList in reference
local printerNames = { }
--The selected printer
local selectedPrinter = 1
--The X,Y,Z and facing of the printer
local px,py,pz,pfx,pfz = 0,0,0,0,0
--The form of layering used
local layering = "up"
 
--The animation state of the selection rectangle and image buffer
local rectblink = 0
--The ID for the timer
local recttimer = nil
--The radius of the brush tool
local brushsize = 3
--Whether or not "record" mode is activated (animation mode only)
local record = false
--The time between each frame when in play mode (animation mode only)
local animtime = 0.3
 
--The current "cursor position" in text mode
local cursorTexX,cursorTexY = 1,1
 
--A list of hexidecimal conversions from numbers to hex digits
local hexnums = { [10] = "a", [11] = "b", [12] = "c", [13] = "d", [14] = "e" , [15] = "f" }
--The NPaintPro logo (divine, isn't it?)
local logo = {
"fcc              3   339";
" fcc          9333    33";
"  fcc        933 333  33";
"   fcc       933  33  33";
"    fcc      933   33 33";
"     c88     333   93333";
"     888     333    9333";
"      333 3  333     939";
}
--The Layer Up and Layer Forward printing icons
local layerUpIcon = {
        "0000000";
        "0088880";
        "0888870";
        "07777f0";
        "0ffff00";
        "0000000";
}
local layerForwardIcon = {
        "0000000";
        "000fff0";
        "00777f0";
        "0888700";
        "0888000";
        "0000000";
}
--The available menu options in the ctrl menu
local mChoices = {"Save","Exit"}
--The available modes from the dropdown menu- tables indicate submenus (include a name!)
local ddModes = { { "paint", "brush", "pippette", "flood", "move", "clear", "select", name = "painting" }, { "alpha to left", "alpha to right", "hide interface", name = "display" }, "help", { "print", "save", "exit", name = "file" }, name = "menu" }
--The available modes from the selection right-click menu
local srModes = { "cut", "copy", "paste", "clear", "hide", name = "selection" }
--The list of available help topics for each mode 127
local helpTopics = {
        [1] = {
                name = "Paint Mode",
                key = nil,
                animonly = false,
                textonly = false,
                message = "The default mode for NPaintPro, for painting pixels."
                .." Controls here that are not overridden will apply for all other modes. Leaving a mode by selecting that mode "
                .." again will always send the user back to paint mode.",
                controls = {
                        { "Arrow keys", "Scroll the canvas" },
                        { "Left Click", "Paint/select left colour" },
                        { "Right Click", "Paint/select right colour" },
                        { "Z Key", "Clear image on screen" },
                        { "Tab Key", "Hide selection rectangle if visible" },
                        { "Q Key", "Set alpha mask to left colour" },
                        { "W Key", "Set alpha mask to right colour" },
                        { "Number Keys", "Swich between frames 1-9" },
                        { "</> keys", "Move to the next/last frame" },
                        { "R Key", "Removes every frame after the current frame"}
                }
        },
        [2] = {
                name = "Brush Mode",
                key = "b",
                animonly = false,
                textonly = false,
                message = "Brush mode allows painting a circular area of variable diameter rather than a single pixel, working in "..
                "the exact same way as paint mode in all other regards.",
                controls = {
                        { "Left Click", "Paints a brush blob with the left colour" },
                        { "Right Click", "Paints a brush blob with the right colour" },
                        { "Number Keys", "Changes the radius of the brush blob from 2-9" }
                }
        },
        [3] = {
                name = "Pippette Mode",
                key = "p",
                animonly = false,
                textonly = false,
                message = "Pippette mode allows the user to click the canvas and set the colour clicked to the left or right "..
                "selected colour, for later painting.",
                controls = {
                        { "Left Click", "Sets clicked colour to the left selected colour" },
                        { "Right Click", "Sets clicked colour to the right selected colour" }
                }
        },
        [4] = {
                name = "Move Mode",
                key = "m",
                animonly = false,
                textonly = false,
                message = "Mode mode allows the moving of the entire image on the screen. This is especially useful for justifying"..
                " the image to the top-left for animations or game assets.",
                controls = {
                        { "Left/Right Click", "Moves top-left corner of image to selected square" },
                        { "Arrow keys", "Moves image one pixel in any direction" }
                }
        },
        [5] = {
                name = "Flood Mode",
                key = "f",
                animonly = false,
                textonly = false,
                message = "Flood mode allows the changing of an area of a given colour to that of the selected colour. "..
                "The tool uses a flood4 algorithm and will not fill diagonally. Transparency cannot be flood filled.",
                controls = {
                        { "Left Click", "Flood fills selected area to left colour" },
                        { "Right Click", "Flood fills selected area to right colour" }
                }
        },
        [6] = {
                name = "Select Mode",
                key = "s",
                animonly = false,
                textonly = false,
                message = "Select mode allows the creation and use of the selection rectangle, to highlight specific areas on "..
                "the screen and perform operations on the selected area of the image. The selection rectangle can contain an "..
                "image on the clipboard- if it does, the image will flash inside the rectangle, and the rectangle edges will "..
                "be light grey instead of dark grey.",
                controls = {
                        { "C Key", "Copy: Moves selection into the clipboard" },
                        { "X Key", "Cut: Clears canvas under the rectangle, and moves it into the clipboard" },
                        { "V Key", "Paste: Copys clipboard to the canvas" },
                        { "Z Key", "Clears clipboard" },
                        { "Left Click", "Moves top-left corner of rectangle to selected pixel" },
                        { "Right Click", "Opens selection menu" },
                        { "Arrow Keys", "Moves rectangle one pixel in any direction" }
                }
        },
        [7] = {
                name = "Corner Select Mode",
                key = nil,
                animonly = false,
                textonly = false,
                message = "If a selection rectangle isn't visible, this mode is selected automatically. It allows the "..
                "defining of the corners of the rectangle- one the top-left and bottom-right corners have been defined, "..
                "NPaintPro switches to selection mode. Note rectangle must be at least 2 pixels wide and high.",
                controls = {
                        { "Left/Right Click", "Defines a corner of the selection rectangle" }
                }
        },
        [8] = {
                name = "Play Mode",
                key = "space",
                animonly = true,
                textonly = false,
                message = "Play mode will loop through each frame in your animation at a constant rate. Editing tools are "..
                "locked in this mode, and the coordinate display will turn green to indicate it is on.",
                controls = {
                        { "</> Keys", "Increases/Decreases speed of the animation" },
                        { "Space Bar", "Returns to paint mode" }
                }
        },
        [9] = {
                name = "Record Mode",
                key = "\\",
                animonly = true,
                textonly = false,
                message = "Record mode is not a true mode, but influences how other modes work. Changes made that modify the "..
                "canvas in record mode will affect ALL frames in the animation. The coordinates will turn red to indicate that "..
                "record mode is on.",
                controls = {
                        { "", "Affects:" },
                        { "- Paint Mode", "" },
                        { "- Brush Mode", "" },
                        { "- Cut and Paste in Select Mode", ""},
                        { "- Move Mode", ""}
                }
        },
		[10] = {
				name = "Hide Interface",
				key = "~",
				animonly = false,
				textonly = false,
				message = "Hides the sidebar and colour picker so only the image is visible."..
				" The program can be started with the interface hidden using the -d command line option."..
				" When hidden, if a file is animated it will automatically go to play mode.\n"..
				"Note that all other input is locked until the display is revealed again in this"..
				" mode.",
				controls = {
                    { "</> Keys", "Increases/Decreases speed of the animation" },
					{ "~ Key", "Shows interface"}
				}
		},
        [11] = {
                name = "Help Mode",
                key = "h",
                animonly = false,
                textonly = false,
                message = "Displays this help screen. Clicking on options will display help on that topic. Clicking out of the screen"..
                " will leave this mode.",
                controls = {
                        { "Left/Right Click", "Displays a topic/Leaves the mode" }
                }
        },
        [12] = {
                name = "File Mode",
                key = nil,
                animonly = false,
                textonly = false,
                message = "Clicking on the mode display at the bottom of the screen will open the options menu. Here you can"..
                " activate all of the modes in the program with a simple mouse click. Pressing left control will open up the"..
                " file menu automatically.",
                controls = {
                        { "leftCtrl", "Opens the file menu" },
                        { "leftAlt", "Opens the paint menu" }
                }
        },
        [13] = {
                name = "Text Mode",
                key = "t",
                animonly = false,
                textonly = true,
                message = "In this mode, the user is able to type letters onto the document for display. The left colour "..
                "pallette value determines what colour the text will be, and the right determines what colour the background "..
                "will be (set either to nil to keep the same colours as already there).",
                controls = {
                        { "Backspace", "Deletes the character on the previous line" },
                        { "Arrow Keys", "Moves the cursor in any direction" },
                        { "Left Click", "Moves the cursor to beneath the mouse cursor" }
                }
        },
        [14] = {
                name = "Textpaint Mode",
                key = "y",
                animonly = false,
                textonly = true,
                message = "Allows the user to paint any text on screen to the desired colour with the mouse. If affects the text colour"..
                " values rather than the background values, but operates identically to paint mode in all other regards.",
                controls = {
                        { "Left Click", "Paints the text with the left colour" },
                        { "Right Click", "Paints the text with the right colour" }
                }
        },
        [15] = {
                name = "About NPaintPro",
                keys = nil,
                animonly = false,
                textonly = false,
                message = "NPaintPro: The feature-bloated paint program for ComputerCraft by Nitrogen Fingers.",
                controls = {
                        { "Testers:", " "},
                        { " ", "Faubiguy"},
                        { " ", "TheOriginalBIT"}
                }
        }
}
--The "bounds" of the image- the first/last point on both axes where a pixel appears
local toplim,botlim,leflim,riglim = nil,nil,nil,nil
--The selected path
local sPath = nil


--Screen Size Parameters- decided dynamically further down the program
--Whether or not the help screen is available
local helpAvailable = true
--Whether or not the main menu is available
local mainAvailable = true
--Whether or not selection box dropdowns are available
local boxdropAvailable = true
--Whether or not a manual file descriptor option is available (part of the title)
local filemakerAvailable = true
 
--[[  
                        Section:  Helpers              
]]--
 
--[[Converts a colour parameter into a single-digit hex coordinate for the colour
    Params: colour:int = The colour to be converted
        Returns:string A string conversion of the colour
]]--
local function getHexOf(colour)
        if not colour or not tonumber(colour) then
                return " "
        end
        local value = math.log(colour)/math.log(2)
        if value > 9 then
                value = hexnums[value]
        end
        return value
end
 
--[[Converts a hex digit into a colour value
        Params: hex:?string = the hex digit to be converted
        Returns:string A colour value corresponding to the hex, or nil if the character is invalid
]]--
local function getColourOf(hex)
        local value = tonumber(hex, 16)
        if not value then return nil end
        value = math.pow(2,value)
        return value
end
 
--[[Finds the largest width and height of the text in a given menu. Should conform to the format
	of all standard menus (number indexed values and a 'name' field).
	This is done recursively. It's just easier that way.
	Params: menu:table = the table being tested for the max width and height
	Returns:number,number = the max width and height of the text or names of any menu or submenu.
]]--
local function findMaxWH(menu)
	local wmax,hmax = #menu.name, #menu
	for _,entry in pairs(menu) do
		if type(entry) == "table" then
			local nw,nh = findMaxWH(entry)
			wmax = math.max(wmax,nw)
			hmax = math.max(hmax,nh)
		else
			wmax = math.max(wmax,#entry)
		end
	end
	return wmax,hmax
end
 
--[[Determines what services are available depending on the size of the screen. Certain features
	may be disabled with screen real estate does not allow for it.
	Params: none
	Returns:nil
]]--
local function determineAvailableServices()
	--Help files were designed to fit a 'standard' CC screen, of 51 x 19. The height of the screen
	--needs to match the number of available options plus white space, but for consistency with
	--the files themselves, a natural size of 51 is required for the screen width as well.
	if w < 51 or h < #helpTopics+3 then helpAvailable = false end
	if not helpAvailable then table.remove(ddModes,3) end
	--These hard-coded values mirror the drawLogo values, with extra consideration for the 
	--additional menu options
	if h < 14 or w < 24 then filemakerAvailable = false end
	
	--Menus can't cover the picker and need 2 spaces for branches. 4 whitespace on X total.
	--Menus need a title and can't eclipse the footer. 2 whitespace on Y total.
	local wmin,hmin = findMaxWH(ddModes)
	if w < wmin+4 or h < hmin+2 then mainAvailable = false end
	wmin,hmin = findMaxWH(srModes)
	if w < wmin+4 or h < hmin+2 then boxdropAvailable = false end
end
 
--[[Finds the biggest and smallest bounds of the image- the outside points beyond which pixels do not appear
        These values are assigned to the "lim" parameters for access by other methods
        Params: forAllFrames:bool = True if all frames should be used to find bounds, otherwise false or nil
        Returns:nil
]]--
local function updateImageLims(forAllFrames)
        local f,l = sFrame,sFrame
        if forAllFrames == true then f,l = 1,framecount end
       
        toplim,botlim,leflim,riglim = nil,nil,nil,nil
        for locf = f,l do
                for y,_ in pairs(frames[locf]) do
                        if type(y) == "number" then
                                for x,_ in pairs(frames[locf][y]) do
                                        if frames[locf][y][x] ~= nil then
                                                if leflim == nil or x < leflim then leflim = x end
                                                if toplim == nil or y < toplim then toplim = y end
                                                if riglim == nil or x > riglim then riglim = x end
                                                if botlim == nil or y > botlim then botlim = y end
                                        end
                                end
                        end
                end
        end
       
        --There is just... no easier way to do this. It's horrible, but necessary
        if textEnabled then
                for locf = f,l do
                        for y,_ in pairs(frames[locf].text) do
                                for x,_ in pairs(frames[locf].text[y]) do
                                        if frames[locf].text[y][x] ~= nil then
                                                if leflim == nil or x < leflim then leflim = x end
                                                if toplim == nil or y < toplim then toplim = y end
                                                if riglim == nil or x > riglim then riglim = x end
                                                if botlim == nil or y > botlim then botlim = y end
                                        end
                                end
                        end
                        for y,_ in pairs(frames[locf].textcol) do
                                for x,_ in pairs(frames[locf].textcol[y]) do
                                        if frames[locf].textcol[y][x] ~= nil then
                                                if leflim == nil or x < leflim then leflim = x end
                                                if toplim == nil or y < toplim then toplim = y end
                                                if riglim == nil or x > riglim then riglim = x end
                                                if botlim == nil or y > botlim then botlim = y end
                                        end
                                end
                        end
                end
        end
end
 
--[[Determines how much of each material is required for a print. Done each time printing is called.
        Params: none
        Returns:table A complete list of how much of each material is required.
]]--
function calculateMaterials()
        updateImageLims(animated)
        requiredMaterials = {}
        for i=1,16 do
                requiredMaterials[i] = 0
        end
       
        if not toplim then return end
       
        for i=1,#frames do
                for y = toplim, botlim do
                        for x = leflim, riglim do
                                if type(frames[i][y][x]) == "number" then
                                        requiredMaterials[math.log10(frames[i][y][x])/math.log10(2) + 1] =
                                                requiredMaterials[math.log10(frames[i][y][x])/math.log10(2) + 1] + 1
                                end    
                        end
                end
        end
end
 
 
--[[Updates the rectangle blink timer. Should be called anywhere events are captured, along with a timer capture.
        Params: nil
        Returns:nil
]]--
local function updateTimer(id)
        if id == recttimer then
                recttimer = os.startTimer(0.5)
                rectblink = (rectblink % 2) + 1
        end
end
 
--[[Constructs a message based on the state currently selected
        Params: nil
        Returns:string A message regarding the state of the application
]]--
local function getStateMessage()
        local msg = " "..string.upper(string.sub(state, 1, 1))..string.sub(state, 2, #state).." mode"
        if state == "brush" then msg = msg..", size="..brushsize end
        return msg
end
 
--[[Calls the rednet_message event, but also looks for timer events to keep then
        system timer ticking.
        Params: timeout:number how long before the event times out
        Returns:number the id of the sender
                   :number the message send
]]--
local function rsTimeReceive(timeout)
        local timerID
        if timeout then timerID = os.startTimer(timeout) end
       
        local id,key,msg = nil,nil
        while true do
                id,key,msg = os.pullEvent()
               
                if id == "timer" then
                        if key == timerID then return
                        else updateTimer(key) end
                end
                if id == "rednet_message" then
                        return key,msg
                end
        end
end
 
--[[Draws a picture, in paint table format on the screen
        Params: image:table = the image to display
                        xinit:number = the x position of the top-left corner of the image
                        yinit:number = the y position of the top-left corner of the image
                        alpha:number = the color to display for the alpha channel. Default is white.
        Returns:nil
]]--
local function drawPictureTable(image, xinit, yinit, alpha)
        if not alpha then alpha = 1 end
        for y=1,#image do
                for x=1,#image[y] do
                        term.setCursorPos(xinit + x-1, yinit + y-1)
                        local col = getColourOf(string.sub(image[y], x, x))
                        if not col then col = alpha end
                        term.setBackgroundColour(col)
                        term.write(" ")
                end
        end
end
 
--[[  
                        Section: Loading  
]]--
 
--[[Loads a non-animted paint file into the program
        Params: path:string = The path in which the file is located
        Returns:nil
]]--
local function loadNFP(path)
        sFrame = 1
        frames[sFrame] = { }
        if fs.exists(path) then
                local file = io.open(path, "r" )
                local sLine = file:read()
                local num = 1
                while sLine do
                        table.insert(frames[sFrame], num, {})
                        for i=1,#sLine do
                                frames[sFrame][num][i] = getColourOf(string.sub(sLine,i,i))
                        end
                        num = num+1
                        sLine = file:read()
                end
                file:close()
        end
end
 
--[[Loads a text-paint file into the program
        Params: path:string = The path in which the file is located
        Returns:nil
]]--
local function loadNFT(path)
        sFrame = 1
        frames[sFrame] = { }
        frames[sFrame].text = { }
        frames[sFrame].textcol = { }
       
        if fs.exists(path) then
                local file = io.open(path, "r")
                local sLine = file:read()
                local num = 1
                while sLine do
                        table.insert(frames[sFrame], num, {})
                        table.insert(frames[sFrame].text, num, {})
                        table.insert(frames[sFrame].textcol, num, {})
                       
                        --As we're no longer 1-1, we keep track of what index to write to
                        local writeIndex = 1
                        --Tells us if we've hit a 30 or 31 (BG and FG respectively)- next char specifies the curr colour
                        local bgNext, fgNext = false, false
                        --The current background and foreground colours
                        local currBG, currFG = nil,nil
                        term.setCursorPos(1,1)
                        for i=1,#sLine do
                                local nextChar = string.sub(sLine, i, i)
                                if nextChar:byte() == 30 then
                                        bgNext = true
                                elseif nextChar:byte() == 31 then
                                        fgNext = true
                                elseif bgNext then
                                        currBG = getColourOf(nextChar)
                                        bgNext = false
                                elseif fgNext then
                                        currFG = getColourOf(nextChar)
                                        fgNext = false
                                else
                                        if nextChar ~= " " and currFG == nil then
                                                currFG = colours.white
                                        end
                                        frames[sFrame][num][writeIndex] = currBG
                                        frames[sFrame].textcol[num][writeIndex] = currFG
                                        frames[sFrame].text[num][writeIndex] = nextChar
                                        writeIndex = writeIndex + 1
                                end
                        end
                        num = num+1
                        sLine = file:read()
                end
                file:close()
        end
end
 
--[[Loads an animated paint file into the program
        Params: path:string = The path in which the file is located
        Returns:nil
]]--
local function loadNFA(path)
        frames[sFrame] = { }
        if fs.exists(path) then
                local file = io.open(path, "r" )
                local sLine = file:read()
                local num = 1
                while sLine do
                        table.insert(frames[sFrame], num, {})
                        if sLine == "~" then
                                sFrame = sFrame + 1
                                frames[sFrame] = { }
                                num = 1
                        else
                                for i=1,#sLine do
                                        frames[sFrame][num][i] = getColourOf(string.sub(sLine,i,i))
                                end
                                num = num+1
                        end
                        sLine = file:read()
                end
                file:close()
        end
        framecount = sFrame
        sFrame = 1
end
 
--[[Saves a non-animated paint file to the specified path
        Params: path:string = The path to save the file to
        Returns:nil
]]--
local function saveNFP(path)
        local sDir = string.sub(sPath, 1, #sPath - #fs.getName(sPath))
        if not fs.exists(sDir) then
                fs.makeDir(sDir)
        end
 
        local file = io.open(path, "w")
        updateImageLims(false)
        if not toplim then
                file:close()
                return
        end
        for y=1,botlim do
                local line = ""
                if frames[sFrame][y] then
                        for x=1,riglim do
                                line = line..getHexOf(frames[sFrame][y][x])
                        end
                end
                file:write(line.."\n")
        end
        file:close()
end
 
--[[Saves a text-paint file to the specified path
        Params: path:string = The path to save the file to
        Returns:nil
]]--
local function saveNFT(path)
        local sDir = string.sub(sPath, 1, #sPath - #fs.getName(sPath))
        if not fs.exists(sDir) then
                fs.makeDir(sDir)
        end
       
        local file = io.open(path, "w")
        updateImageLims(false)
        if not toplim then
                file:close()
                return
        end
        for y=1,botlim do
                local line = ""
                local currBG, currFG = nil,nil
                for x=1,riglim do
                        if frames[sFrame][y] and frames[sFrame][y][x] ~= currBG then
                                line = line..string.char(30)..getHexOf(frames[sFrame][y][x])
                                currBG = frames[sFrame][y][x]
                        end
                        if frames[sFrame].textcol[y] and frames[sFrame].textcol[y][x] ~= currFG then
                                line = line..string.char(31)..getHexOf(frames[sFrame].textcol[y][x])
                                currFG = frames[sFrame].textcol[y][x]
                        end
                        if frames[sFrame].text[y] then
                                local char = frames[sFrame].text[y][x]
                                if not char then char = " " end
                                line = line..char
                        end
                end
                file:write(line.."\n")
        end
        file:close()
end
 
--[[Saves a animated paint file to the specified path
        Params: path:string = The path to save the file to
        Returns:nil
]]--
local function saveNFA(path)
        local sDir = string.sub(sPath, 1, #sPath - #fs.getName(sPath))
        if not fs.exists(sDir) then
                fs.makeDir(sDir)
        end
       
        local file = io.open(path, "w")
        updateImageLims(true)
        if not toplim then
                file:close()
                return
        end
        for i=1,#frames do
                for y=1,botlim do
                        local line = ""
                        if frames[i][y] then
                                for x=1,riglim do
                                        line = line..getHexOf(frames[i][y][x])
                                end
                        end
                        file:write(line.."\n")
                end
                if i < #frames then file:write("~\n") end
        end
        file:close()
end

--[[Runs a special pre-program dialogue to determine the filename and filepath. Done if
	there's room, and a file name hasn't been specified
	Params: none
	Returns:bool= true if file is created; false otherwise
]]--
local function runFileMaker()
	local newFName = ""
	local fileType = 1
	if animated then fileType = 2
	elseif textEnabled then fileType = 3 end
	
	local tlx,tly = math.floor(w/2 - #logo[1]/2), math.floor(h/2 + #logo/2 + 1)

	--This is done on top of the logo, so it backpedals a bit.
	term.setCursorPos(tlx, tly)
	term.clearLine()
	term.write("Name: ")
	term.setCursorPos(tlx, tly + 1)
	term.clearLine()
	term.write("Filetype:   Sprite")
	term.setCursorPos(tlx + 12, tly + 2)
	term.write("Animation")
	term.setCursorPos(tlx + 12, tly + 3)
	term.write("Text")
	
	while true do
		term.setCursorPos(tlx + 6, tly)
		term.setBackgroundColour(colours.lightGrey)
		term.setTextColour(colours.grey)
		term.write(newFName..string.rep(" ", 15-#newFName))
		term.setBackgroundColour(colours.white)
		term.setTextColour(colours.black)
		local extension = ".nfp"
		if fileType == 2 then extension = ".nfa"
		elseif fileType == 3 then extension = ".nft" end
		term.write(extension)
		
		term.setBackgroundColour(colours.lightGrey)
		term.setTextColour(colours.grey)
		for i=1,3 do
			term.setCursorPos(tlx + 24, tly + i)
			if i==fileType then term.write("X")
			else term.write(" ") end
		end
		
		local fPath = shell.resolve(newFName..extension)
		term.setCursorPos(tlx, tly + 3)
		local fileValid = true
		if (fs.exists(fPath) and fs.isDir(fPath)) or newFName == "" then
			term.setBackgroundColour(colours.white)
			term.setTextColour(colours.red)
			term.write("Invalid ")
			fileValid = false
		elseif fs.exists(fPath) then
			term.setBackgroundColour(colours.grey)
			term.setTextColour(colours.lightGrey)
			term.write(" Edit  ")
		else
			term.setBackgroundColour(colours.grey)
			term.setTextColour(colours.lightGrey)
			term.write(" Create ")
		end
		
		term.setTextColour(colours.grey)
		term.setCursorPos(tlx + 6 + #newFName, tly)
		term.setCursorBlink(true)
		
		local id,p1,p2,p3 = os.pullEvent()
		if id == "key" then
			if p1 == keys.backspace and #newFName > 0 then 
				newFName = string.sub(newFName, 1, #newFName-1)
			elseif p1 == keys.enter and fileValid then
				sPath = fPath
				return true
			end
		elseif id == "char" and p1 ~= "." and p1 ~= " " and #newFName < 15 then
			newFName = newFName..p1
		elseif id == "mouse_click" then
			--The option boxes. Man, hardcoding is ugly...
			if p2 == tlx + 24 then
				for i=1,3 do 
					if p3 == tly+i then fileType = i end 
				end
			end
			if p3 == tly + 3 and p2 >= tlx and p2 <= tlx + 8 and fileValid then
				sPath = fPath
				return true
			end
		end
	end
end
 
--[[Initializes the program, by loading in the paint file. Called at the start of each program.
        Params: none
        Returns:nil
]]--
local function init()
        if textEnabled then
                loadNFT(sPath)
                table.insert(ddModes, 2, { "text", "textpaint", name = "text"})
        elseif animated then
                loadNFA(sPath)
                table.insert(ddModes, #ddModes, { "record", "play", name = "anim" })
                table.insert(ddModes, #ddModes, { "go to", "remove", name = "frames"})
                table.insert(ddModes[2], #ddModes[2], "blueprint on")
                table.insert(ddModes[2], #ddModes[2], "layers on")
        else
                loadNFP(sPath)
                table.insert(ddModes[2], #ddModes[2], "blueprint on")
        end
		
        for i=0,15 do
                table.insert(column, math.pow(2,i))
        end
end
 
--[[  
                        Section: Drawing  
]]--
 
 
--[[Draws the rather superflous logo. Takes about 1 second, before user is able to move to the
        actual program.
        Params: none
        Returns:bool= true if the file select ran successfully; false otherwise.
]]--
local function drawLogo()
        term.setBackgroundColour(colours.white)
        term.clear()
		if h >= 12 and w >= 24 then
			drawPictureTable(logo, w/2 - #logo[1]/2, h/2 - #logo/2, colours.white)
			term.setBackgroundColour(colours.white)
			term.setTextColour(colours.black)
			local msg = "NPaintPro"
			term.setCursorPos(w/2 - #msg/2, h/2 + #logo/2 + 1)
			term.write(msg)
			msg = "By NitrogenFingers"
			term.setCursorPos(w/2 - #msg/2, h/2 + #logo/2 + 2)
			term.write(msg)
        elseif w >= 15 then
			local msg = "NPaintPro"
			term.setCursorPos(math.ceil(w/2 - #msg/2), h/2)
			term.setTextColour(colours.cyan)
			term.write(msg)
			msg = "NitrogenFingers"
			term.setCursorPos(math.ceil(w/2 - #msg/2), h/2 + 1)
			term.setTextColour(colours.black)
			term.write(msg)
		else
			local msg = "NPP"
			term.setCursorPos(math.ceil(w/2 - #msg/2), math.floor(h/2))
			term.setTextColour(colours.cyan)
			term.write(msg)
			msg = "By NF"
			term.setCursorPos(math.ceil(w/2 - #msg/2), math.ceil(h/2))
			term.setTextColour(colours.black)
			term.write(msg)
		end
        os.pullEvent()
end
 
--[[Clears the display to the alpha channel colour, draws the canvas, the image buffer and the selection
        rectanlge if any of these things are present.
        Params: none
        Returns:nil
]]--
local function drawCanvas()
        --We have to readjust the position of the canvas if we're printing
        turtlechar = "@"
        if state == "active print" then
                if layering == "up" then
                        if py >= 1 and py <= #frames then
                                sFrame = py
                        end
                        if pz < sy then sy = pz
                        elseif pz > sy + h - 1 then sy = pz + h - 1 end
                        if px < sx then sx = px
                        elseif px > sx + w - 2 then sx = px + w - 2 end
                else
                        if pz >= 1 and pz <= #frames then
                                sFrame = pz
                        end
                       
                        if py < sy then sy = py
                        elseif py > sy + h - 1 then sy = py + h - 1 end
                        if px < sx then sx = px
                        elseif px > sx + w - 2 then sx = px + w - 2 end
                end
               
                if pfx == 1 then turtlechar = ">"
                elseif pfx == -1 then turtlechar = "<"
                elseif pfz == 1 then turtlechar = "V"
                elseif pfz == -1 then turtlechar = "^"
                end
        end
 
        --Picture next
        local topLayer, botLayer
        if layerDisplay then
                topLayer = sFrame
                botLayer = 1
        else
                topLayer,botLayer = sFrame,sFrame
        end
       
	    --How far the canvas draws. If the interface is visible, it stops short of that.
	    local wlim,hlim = 0,0
		if not interfaceHidden then
			wlim = 2
			hlim = 1
		end
	   
        for currframe = botLayer,topLayer,1 do
                for y=sy+1,sy+h-hlim do
                        if frames[currframe][y] then
                                for x=sx+1,sx+w-wlim do
                                        term.setCursorPos(x-sx,y-sy)
                                        if frames[currframe][y][x] then
                                                term.setBackgroundColour(frames[currframe][y][x])
                                                if textEnabled and frames[currframe].textcol[y][x] and frames[currframe].text[y][x] then
                                                        term.setTextColour(frames[currframe].textcol[y][x])
                                                        term.write(frames[currframe].text[y][x])
                                                else
                                                        term.write(" ")
                                                end
                                        else
                                                tileExists = false
                                                for i=currframe-1,botLayer,-1 do
                                                        if frames[i][y][x] then
                                                                tileExists = true
                                                                break
                                                        end
                                                end
                                               
                                                if not tileExists then
                                                        if blueprint then
                                                                term.setBackgroundColour(colours.blue)
                                                                term.setTextColour(colours.white)
                                                                if x == sx+1 and y % 4 == 1 then
                                                                        term.write(""..((y/4) % 10))
                                                                elseif y == sy + 1 and x % 4 == 1 then
                                                                        term.write(""..((x/4) % 10))
                                                                elseif x % 2 == 1 and y % 2 == 1 then
                                                                        term.write("+")
                                                                elseif x % 2 == 1 then
                                                                        term.write("|")
                                                                elseif y % 2 == 1 then
                                                                        term.write("-")
                                                                else
                                                                        term.write(" ")
                                                                end
                                                        else
                                                                term.setBackgroundColour(alphaC)
                                                                if textEnabled and frames[currframe].textcol[y][x] and frames[currframe].text[y][x] then
                                                                        term.setTextColour(frames[currframe].textcol[y][x])
                                                                        term.write(frames[currframe].text[y][x])
                                                                else
                                                                        term.write(" ")
                                                                end
                                                        end
                                                end
                                        end
                                end
                        else
                                for x=sx+1,sx+w-wlim do
                                        term.setCursorPos(x-sx,y-sy)
                                       
                                        tileExists = false
                                        for i=currframe-1,botLayer,-1 do
                                                if frames[i][y] and frames[i][y][x] then
                                                        tileExists = true
                                                        break
                                                end
                                        end
                                       
                                        if not tileExists then
                                                if blueprint then
                                                        term.setBackgroundColour(colours.blue)
                                                        term.setTextColour(colours.white)
                                                        if x == sx+1 and y % 4 == 1 then
                                                                term.write(""..((y/4) % 10))
                                                        elseif y == sy + 1 and x % 4 == 1 then
                                                                term.write(""..((x/4) % 10))
                                                        elseif x % 2 == 1 and y % 2 == 1 then
                                                                term.write("+")
                                                        elseif x % 2 == 1 then
                                                                term.write("|")
                                                        elseif y % 2 == 1 then
                                                                term.write("-")
                                                        else
                                                                term.write(" ")
                                                        end
                                                else
                                                        term.setBackgroundColour(alphaC)
                                                        term.write(" ")
                                                end
                                        end
                                end
                        end
                end
        end
       
        --Then the printer, if he's on
        if state == "active print" then
                local bgColour = alphaC
                if layering == "up" then
                        term.setCursorPos(px-sx,pz-sy)
                        if frames[sFrame] and frames[sFrame][pz-sy] and frames[sFrame][pz-sy][px-sx] then
                                bgColour = frames[sFrame][pz-sy][px-sx]
                        elseif blueprint then bgColour = colours.blue end
                else
                        term.setCursorPos(px-sx,py-sy)
                        if frames[sFrame] and frames[sFrame][py-sy] and frames[sFrame][py-sy][px-sx] then
                                bgColour = frames[sFrame][py-sy][px-sx]
                        elseif blueprint then bgColour = colours.blue end
                end
               
                term.setBackgroundColour(bgColour)
                if bgColour == colours.black then term.setTextColour(colours.white)
                else term.setTextColour(colours.black) end
               
                term.write(turtlechar)
        end
       
        --Then the buffer
        if selectrect then
                if buffer and rectblink == 1 then
                for y=selectrect.y1, math.min(selectrect.y2, selectrect.y1 + buffer.height-1) do
                        for x=selectrect.x1, math.min(selectrect.x2, selectrect.x1 + buffer.width-1) do
                                if buffer.contents[y-selectrect.y1+1][x-selectrect.x1+1] then
                                        term.setCursorPos(x+sx,y+sy)
                                        term.setBackgroundColour(buffer.contents[y-selectrect.y1+1][x-selectrect.x1+1])
                                        term.write(" ")
                                end
                        end
                end
                end
       
                --This draws the "selection" box
                local add = nil
                if buffer then
                        term.setBackgroundColour(colours.lightGrey)
                else
                        term.setBackgroundColour(colours.grey)
                end
                for i=selectrect.x1, selectrect.x2 do
                        add = (i + selectrect.y1 + rectblink) % 2 == 0
                        term.setCursorPos(i-sx,selectrect.y1-sy)
                        if add then term.write(" ") end
                        add = (i + selectrect.y2 + rectblink) % 2 == 0
                        term.setCursorPos(i-sx,selectrect.y2-sy)
                        if add then term.write(" ") end
                end
                for i=selectrect.y1 + 1, selectrect.y2 - 1 do
                        add = (i + selectrect.x1 + rectblink) % 2 == 0
                        term.setCursorPos(selectrect.x1-sx,i-sy)
                        if add then term.write(" ") end
                        add = (i + selectrect.x2 + rectblink) % 2 == 0
                        term.setCursorPos(selectrect.x2-sx,i-sy)
                        if add then term.write(" ") end
                end
        end
end
 
--[[Draws the colour picker on the right side of the screen, the colour pallette and the footer with any
        messages currently being displayed
        Params: none
        Returns:nil
]]--
local function drawInterface()
        --Picker
		local coffset,ioffset = 0,0
		local maxcsize = h-2
		if h < #column + 2 then
			maxcsize = h-4
			coffset = columnoffset
			ioffset = 1
			term.setBackgroundColour(colours.lightGrey)
			term.setTextColour(colours.grey)
			term.setCursorPos(w-1,1)
			term.write("^^")
			term.setCursorPos(w-1,h-2)
			term.write("VV")
		end
        for i=1,math.min(#column+1,maxcsize) do
			term.setCursorPos(w-1, i + ioffset)
			local ci = i+coffset
			if ci == #column+1 then
				term.setBackgroundColour(colours.black)
				term.setTextColour(colours.red)
				term.write("XX")
			elseif state == "print" then
				term.setBackgroundColour(column[ci])
				if column[ci] == colours.black then
					term.setTextColour(colours.white)
				else term.setTextColour(colours.black) end
				
				if requirementsDisplayed then
						if requiredMaterials[i] < 10 then term.write(" ") end
						term.setCursorPos(w-#tostring(requiredMaterials[i])+1, i)
						term.write(requiredMaterials[i])
				else
						if i+coffset < 10 then term.write(" ") end
						term.write(i+coffset)
				end
			else
				term.setBackgroundColour(column[ci])
				term.write("  ")
			end
        end
		--Filling the whitespace with... 'greyspace' *shudder*
		if h > #column+3 then
			term.setTextColour(colours.grey)
			term.setBackgroundColour(colours.lightGrey)
			for y=#column+2,h-2 do
				term.setCursorPos(w-1,y)
				term.write("| ")
			end
		end
        --Pallette
        term.setCursorPos(w-1,h-1)
        if not lSel then
                term.setBackgroundColour(colours.black)
                term.setTextColour(colours.red)
                term.write("X")
        else
                term.setBackgroundColour(lSel)
                term.setTextColour(lSel)
                term.write(" ")
        end
        if not rSel then
                term.setBackgroundColour(colours.black)
                term.setTextColour(colours.red)
                term.write("X")
        else
                term.setBackgroundColour(rSel)
                term.setTextColour(rSel)
                term.write(" ")
        end
        --Footer
        if inMenu then return end
       
        term.setCursorPos(1, h)
        term.setBackgroundColour(colours.lightGrey)
        term.setTextColour(colours.grey)
        term.clearLine()
		if mainAvailable then
			if inDropDown then
					term.write(string.rep(" ", #ddModes.name + 2))
			else
					term.setBackgroundColour(colours.grey)
					term.setTextColour(colours.lightGrey)
					term.write(ddModes.name.."  ")
			end
		end
        term.setBackgroundColour(colours.lightGrey)
        term.setTextColour(colours.grey)
        term.write(getStateMessage())
       
        local coords="X:"..sx.." Y:"..sy
        if animated then coords = coords.." Frame:"..sFrame.."/"..framecount.."   " end
        term.setCursorPos(w-#coords+1,h)
        if state == "play" then term.setBackgroundColour(colours.lime)
        elseif record then term.setBackgroundColour(colours.red) end
        term.write(coords)
       
        if animated then
                term.setCursorPos(w-1,h)
                term.setBackgroundColour(colours.grey)
                term.setTextColour(colours.lightGrey)
                term.write("<>")
        end
end
 
--[[Runs an interface where users can select topics of help. Will return once the user quits the help screen.
        Params: none
        Returns:nil
]]--
local function drawHelpScreen()
        local selectedHelp = nil
        while true do
                term.setBackgroundColour(colours.lightGrey)
                term.clear()
                if not selectedHelp then
                        term.setCursorPos(4, 1)
                        term.setTextColour(colours.brown)
                        term.write("Available modes (click for info):")
                        for i=1,#helpTopics do
                                term.setCursorPos(2, 2 + i)
                                term.setTextColour(colours.black)
                                term.write(helpTopics[i].name)
                                if helpTopics[i].key then
                                        term.setTextColour(colours.red)
                                        term.write(" ("..helpTopics[i].key..")")
                                end
                        end
                        term.setCursorPos(4,h)
                        term.setTextColour(colours.black)
                        term.write("Press any key to exit")
                else
                        term.setCursorPos(4,1)
                        term.setTextColour(colours.brown)
                        term.write(helpTopics[selectedHelp].name)
                        if helpTopics[selectedHelp].key then
                                term.setTextColour(colours.red)
                                term.write(" ("..helpTopics[selectedHelp].key..")")
                        end
                        term.setCursorPos(1,3)
                        term.setTextColour(colours.black)
                        print(helpTopics[selectedHelp].message.."\n")
                        for i=1,#helpTopics[selectedHelp].controls do
                                term.setTextColour(colours.brown)
                                term.write(helpTopics[selectedHelp].controls[i][1].." ")
                                term.setTextColour(colours.black)
                                print(helpTopics[selectedHelp].controls[i][2])
                        end
                end
               
                local id,p1,p2,p3 = os.pullEvent()
               
                if id == "timer" then updateTimer(p1)
                elseif id == "key" then
                        if selectedHelp then selectedHelp = nil
                        else break end
                elseif id == "mouse_click" then
                        if not selectedHelp then
                                if p3 >=3 and p3 <= 2+#helpTopics then
                                        selectedHelp = p3-2
                                else break end
                        else
                                selectedHelp = nil
                        end
                end
        end
end
 
--[[Draws a message in the footer bar. A helper for DrawInterface, but can be called for custom messages, if the
        inMenu paramter is set to true while this is being done (remember to set it back when done!)
        Params: message:string = The message to be drawn
        Returns:nil
]]--
local function drawMessage(message)
        term.setCursorPos(1,h)
        term.setBackgroundColour(colours.lightGrey)
        term.setTextColour(colours.grey)
        term.clearLine()
        term.write(message)
end
 
--[[
                        Section: Generic Interfaces
]]--
 
 
--[[One of my generic text printing methods, printing a message at a specified position with width and offset.
        No colour materials included.
        Params: msg:string = The message to print off-center
                        height:number = The starting height of the message
                        width:number = The limit as to how many characters long each line may be
                        offset:number = The starting width offset of the message
        Returns:number the number of lines used in printing the message
]]--
local function wprintOffCenter(msg, height, width, offset)
        local inc = 0
        local ops = 1
        while #msg - ops > width do
                local nextspace = 0
                while string.find(msg, " ", ops + nextspace) and
                                string.find(msg, " ", ops + nextspace) - ops < width do
                        nextspace = string.find(msg, " ", nextspace + ops) + 1 - ops
                end
                local ox,oy = term.getCursorPos()
                term.setCursorPos(width/2 - (nextspace)/2 + offset, height + inc)
                inc = inc + 1
                term.write(string.sub(msg, ops, nextspace + ops - 1))
                ops = ops + nextspace
        end
        term.setCursorPos(width/2 - #string.sub(msg, ops)/2 + offset, height + inc)
        term.write(string.sub(msg, ops))
       
        return inc + 1
end
 
--[[Draws a message that must be clicked on or a key struck to be cleared. No options, so used for displaying
        generic information.
        Params: ctitle:string = The title of the confirm dialogue
                        msg:string = The message displayed in the dialogue
        Returns:nil
]]--
local function displayConfirmDialogue(ctitle, msg)
        local dialogoffset = 8
        --We actually print twice- once to get the lines, second time to print proper. Easier this way.
        local lines = wprintOffCenter(msg, 5, w - (dialogoffset+2) * 2, dialogoffset + 2)
       
        term.setCursorPos(dialogoffset, 3)
        term.setBackgroundColour(colours.grey)
        term.setTextColour(colours.lightGrey)
        term.write(string.rep(" ", w - dialogoffset * 2))
        term.setCursorPos(dialogoffset + (w - dialogoffset * 2)/2 - #ctitle/2, 3)
        term.write(ctitle)
        term.setTextColour(colours.grey)
        term.setBackgroundColour(colours.lightGrey)
        term.setCursorPos(dialogoffset, 4)
        term.write(string.rep(" ", w - dialogoffset * 2))
        for i=5,5+lines do
                term.setCursorPos(dialogoffset, i)
                term.write(" "..string.rep(" ", w - (dialogoffset) * 2 - 2).." ")
        end
        wprintOffCenter(msg, 5, w - (dialogoffset+2) * 2, dialogoffset + 2)
       
        --In the event of a message, the player hits anything to continue
        while true do
                local id,key = os.pullEvent()
                if id == "timer" then updateTimer(key);
                elseif id == "key" or id == "mouse_click" or id == "mouse_drag" then break end
        end
end
 
--[[Produces a nice dropdown menu based on a table of strings. Depending on the position, this will auto-adjust the position
        of the menu drawn, and allows nesting of menus and sub menus. Clicking anywhere outside the menu will cancel and return nothing
        Params: x:int = the x position the menu should be displayed at
                        y:int = the y position the menu should be displayed at
                        options:table = the list of options available to the user, as strings or submenus (tables of strings, with a name parameter)
        Returns:string the selected menu option.
]]--
local function displayDropDown(x, y, options)
        inDropDown = true
        --Figures out the dimensions of our thing
        local longestX = #options.name
        for i=1,#options do
                local currVal = options[i]
                if type(currVal) == "table" then currVal = currVal.name end
               
                longestX = math.max(longestX, #currVal)
        end
        local xOffset = math.max(0, longestX - ((w-2) - x) + 1)
        local yOffset = math.max(0, #options - ((h-1) - y))
       
        local clickTimes = 0
        local tid = nil
        local selection = nil
        while clickTimes < 2 do
                drawCanvas()
                drawInterface()
               
                term.setCursorPos(x-xOffset,y-yOffset)
                term.setBackgroundColour(colours.grey)
                term.setTextColour(colours.lightGrey)
                term.write(options.name..string.rep(" ", longestX-#options.name + 2))
       
                for i=1,#options do
                        term.setCursorPos(x-xOffset, y-yOffset+i)
                        if i==selection and clickTimes % 2 == 0 then
                                term.setBackgroundColour(colours.grey)
                                term.setTextColour(colours.lightGrey)
                        else
                                term.setBackgroundColour(colours.lightGrey)
                                term.setTextColour(colours.grey)
                        end
                        local currVal = options[i]
                        if type(currVal) == "table" then
                                term.write(currVal.name..string.rep(" ", longestX-#currVal.name + 1))
                                term.setBackgroundColour(colours.grey)
                                term.setTextColour(colours.lightGrey)
                                term.write(">")
                        else
                                term.write(currVal..string.rep(" ", longestX-#currVal + 2))
                        end
                end
               
                local id, p1, p2, p3 = os.pullEvent()
                if id == "timer" then
                        if p1 == tid then
                                clickTimes = clickTimes + 1
                                if clickTimes > 2 then
                                        break
                                else
                                        tid = os.startTimer(0.1)
                                end
                        else
                                updateTimer(p1)
                                drawCanvas()
                                drawInterface()
                        end
                elseif id == "mouse_click" then
                        if p2 >=x-xOffset and p2 <= x-xOffset + longestX + 1 and p3 >= y-yOffset+1 and p3 <= y-yOffset+#options then
                                selection = p3-(y-yOffset)
                                tid = os.startTimer(0.1)
                        else
                                selection = ""
                                break
                        end
                end
        end
       
        if type(selection) == "number" then
                selection = options[selection]
        end
       
        if type(selection) == "string" then
                inDropDown = false
                return selection
        elseif type(selection) == "table" then
                return displayDropDown(x, y, selection)
        end
end
 
--[[A custom io.read() function with a few differences- it limits the number of characters being printed,
        waits a 1/100th of a second so any keys still in the event library are removed before input is read and
        the timer for the selectionrectangle is continuously updated during the process.
        Params: lim:int = the number of characters input is allowed
        Returns:string the inputted string, trimmed of leading and tailing whitespace
]]--
local function readInput(lim)
        term.setCursorBlink(true)
 
        local inputString = ""
        if not lim or type(lim) ~= "number" or lim < 1 then lim = w - ox end
        local ox,oy = term.getCursorPos()
        --We only get input from the footer, so this is safe. Change if recycling
        term.setBackgroundColour(colours.lightGrey)
        term.setTextColour(colours.grey)
        term.write(string.rep(" ", lim))
        term.setCursorPos(ox, oy)
        --As events queue immediately, we may get an unwanted key... this will solve that problem
        local inputTimer = os.startTimer(0.01)
        local keysAllowed = false
       
        while true do
                local id,key = os.pullEvent()
               
                if keysAllowed then
                        if id == "key" and key == 14 and #inputString > 0 then
                                inputString = string.sub(inputString, 1, #inputString-1)
                                term.setCursorPos(ox + #inputString,oy)
                                term.write(" ")
                        elseif id == "key" and key == 28 and inputString ~= string.rep(" ", #inputString) then
                                break
                        elseif id == "key" and key == keys.leftCtrl then
                                return ""
                        elseif id == "char" and #inputString < lim then
                                inputString = inputString..key
                        end
                end
               
                if id == "timer" then
                        if key == inputTimer then
                                keysAllowed = true
                        else
                                updateTimer(key)
                                drawCanvas()
                                drawInterface()
                                term.setBackgroundColour(colours.lightGrey)
                                term.setTextColour(colours.grey)
                        end
                end
                term.setCursorPos(ox,oy)
                term.write(inputString)
                term.setCursorPos(ox + #inputString, oy)
        end
       
        while string.sub(inputString, 1, 1) == " " do
                inputString = string.sub(inputString, 2, #inputString)
        end
        while string.sub(inputString, #inputString, #inputString) == " " do
                inputString = string.sub(inputString, 1, #inputString-1)
        end
        term.setCursorBlink(false)
       
        return inputString
end
 
--[[  
                        Section: Image tools
]]--
 
 
--[[Copies all pixels beneath the selection rectangle into the image buffer. Empty buffers are converted to nil.
        Params: removeImage:bool = true if the image is to be erased after copying, false otherwise
        Returns:nil
]]--
local function copyToBuffer(removeImage)
        buffer = { width = selectrect.x2 - selectrect.x1 + 1, height = selectrect.y2 - selectrect.y1 + 1, contents = { } }
       
        local containsSomething = false
        for y=1,buffer.height do
                buffer.contents[y] = { }
                local f,l = sFrame,sFrame
                if record then f,l = 1, framecount end
               
                for fra = f,l do
                        if frames[fra][selectrect.y1 + y - 1] then
                                for x=1,buffer.width do
                                        buffer.contents[y][x] = frames[sFrame][selectrect.y1 + y - 1][selectrect.x1 + x - 1]
                                        if removeImage then frames[fra][selectrect.y1 + y - 1][selectrect.x1 + x - 1] = nil end
                                        if buffer.contents[y][x] then containsSomething = true end
                                end
                        end
                end
        end
        --I don't classify an empty buffer as a real buffer- confusing to the user.
        if not containsSomething then buffer = nil end
end
 
--[[Replaces all pixels under the selection rectangle with the image buffer (or what can be seen of it). Record-dependent.
        Params: removeBuffer:bool = true if the buffer is to be emptied after copying, false otherwise
        Returns:nil
]]--
local function copyFromBuffer(removeBuffer)
        if not buffer then return end
 
        for y = 1, math.min(buffer.height,selectrect.y2-selectrect.y1+1) do
                local f,l = sFrame, sFrame
                if record then f,l = 1, framecount end
               
                for fra = f,l do
                        if not frames[fra][selectrect.y1+y-1] then frames[fra][selectrect.y1+y-1] = { } end
                        for x = 1, math.min(buffer.width,selectrect.x2-selectrect.x1+1) do
                                frames[fra][selectrect.y1+y-1][selectrect.x1+x-1] = buffer.contents[y][x]
                        end
                end
        end
       
        if removeBuffer then buffer = nil end
end
 
--[[Moves the entire image (or entire animation) to the specified coordinates. Record-dependent.
        Params: newx:int = the X coordinate to move the image to
                        newy:int = the Y coordinate to move the image to
        Returns:nil
]]--
local function moveImage(newx,newy)
        if not leflim or not toplim then return end
        if newx <=0 or newy <=0 then return end
        local f,l = sFrame,sFrame
        if record then f,l = 1,framecount end
       
        for i=f,l do
                local newlines = { }
                for y=toplim,botlim do
                        local line = frames[i][y]
                        if line then
                                newlines[y-toplim+newy] = { }
                                for x,char in pairs(line) do
                                        newlines[y-toplim+newy][x-leflim+newx] = char
                                end
                        end
                end
                --Exceptions that allow us to move the text as well
                if textEnabled then
                        newlines.text = { }
                        for y=toplim,botlim do
                                local line = frames[i].text[y]
                                if line then
                                        newlines.text[y-toplim+newy] = { }
                                        for x,char in pairs(line) do
                                                newlines.text[y-toplim+newy][x-leflim+newx] = char
                                        end
                                end
                        end
                       
                        newlines.textcol = { }
                        for y=toplim,botlim do
                                local line = frames[i].textcol[y]
                                if line then
                                        newlines.textcol[y-toplim+newy] = { }
                                        for x,char in pairs(line) do
                                                newlines.textcol[y-toplim+newy][x-leflim+newx] = char
                                        end
                                end
                        end
                end
               
                frames[i] = newlines
        end
end
 
--[[Prompts the user to clear the current frame or all frames. Record-dependent.,
        Params: none
        Returns:nil
]]--
local function clearImage()
        inMenu = true
        if not animated then
                drawMessage("Clear image? Y/N: ")
        elseif record then
                drawMessage("Clear ALL frames? Y/N: ")
        else
                drawMessage("Clear current frame? Y/N :")
        end
        if string.find(string.upper(readInput(1)), "Y") then
                local f,l = sFrame,sFrame
                if record then f,l = 1,framecount end
               
                for i=f,l do
                        frames[i] = { }
                end
        end
        inMenu = false
end
 
--[[A recursively called method (watch out for big calls!) in which every pixel of a set colour is
        changed to another colour. Does not work on the nil colour, for obvious reasons.
        Params: x:int = The X coordinate of the colour to flood-fill
                        y:int = The Y coordinate of the colour to flood-fill
                        targetColour:colour = the colour that is being flood-filled
                        newColour:colour = the colour with which to replace the target colour
        Returns:nil
]]--
local function floodFill(x, y, targetColour, newColour)
        if not newColour or not targetColour then return end
        local nodeList = { }
       
        table.insert(nodeList, {x = x, y = y})
       
        while #nodeList > 0 do
                local node = nodeList[1]
                if frames[sFrame][node.y] and frames[sFrame][node.y][node.x] == targetColour then
                        frames[sFrame][node.y][node.x] = newColour
                        table.insert(nodeList, { x = node.x + 1, y = node.y})
                        table.insert(nodeList, { x = node.x, y = node.y + 1})
                        if x > 1 then table.insert(nodeList, { x = node.x - 1, y = node.y}) end
                        if y > 1 then table.insert(nodeList, { x = node.x, y = node.y - 1}) end
                end
                table.remove(nodeList, 1)
        end
end
 
--[[  
                        Section: Animation Tools  
]]--
 
--[[Enters play mode, allowing the animation to play through. Interface is restricted to allow this,
        and method only leaves once the player leaves play mode.
        Params: none
        Returns:nil
]]--
local function playAnimation()
        state = "play"
        selectedrect = nil
       
        local animt = os.startTimer(animtime)
        repeat
                drawCanvas()
                drawInterface()
               
                local id,key,_,y = os.pullEvent()
               
                if id=="timer" then
                        if key == animt then
                                animt = os.startTimer(animtime)
                                sFrame = (sFrame % framecount) + 1
                        else
                                updateTimer(key)
                        end
                elseif id=="key" then
                        if key == keys.comma and animtime > 0.1 then animtime = animtime - 0.05
                        elseif key == keys.period and animtime < 0.5 then animtime = animtime + 0.05
                        elseif key == keys.space then state = "paint" end
                elseif id=="mouse_click" and y == h then
                        state = "paint"
                end
        until state ~= "play"
        os.startTimer(0.5)
end
 
--[[Changes the selected frame (sFrame) to the chosen frame. If this frame is above the framecount,
        additional frames are created with a copy of the image on the selected frame.
        Params: newframe:int = the new frame to move to
        Returns:nil
]]--
local function changeFrame(newframe)
        inMenu = true
        if not tonumber(newframe) then
                term.setCursorPos(1,h)
                term.setBackgroundColour(colours.lightGrey)
                term.setTextColour(colours.grey)
                term.clearLine()
       
                term.write("Go to frame: ")
                newframe = tonumber(readInput(2))
                if not newframe or newframe <= 0 then
                        inMenu = false
                        return
                end
        elseif newframe <= 0 then return end
       
        if newframe > framecount then
                for i=framecount+1,newframe do
                        frames[i] = {}
                        for y,line in pairs(frames[sFrame]) do
                                frames[i][y] = { }
                                for x,v in pairs(line) do
                                        frames[i][y][x] = v
                                end
                        end
                end
                framecount = newframe
        end
        sFrame = newframe
        inMenu = false
end
 
--[[Removes every frame leading after the frame passed in
        Params: frame:int the non-inclusive lower bounds of the delete
        Returns:nil
]]--
local function removeFramesAfter(frame)
        inMenu = true
        if frame==framecount then return end
        drawMessage("Remove frames "..(frame+1).."/"..framecount.."? Y/N :")
        local answer = string.upper(readInput(1))
       
        if string.find(answer, string.upper("Y")) ~= 1 then
                inMenu = false
                return
        end
       
        for i=frame+1, framecount do
                frames[i] = nil
        end
        framecount = frame
        inMenu = false
end
 
--[[
                        Section: Printing Tools
]]--
 
--[[Constructs a new facing to the left of the current facing
        Params: curx:number = The facing on the X axis
                        curz:number = The facing on the Z axis
                        hand:string = The hand of the axis ("right" or "left")
        Returns:number,number = the new facing on the X and Z axis after a left turn
]]--
local function getLeft(curx, curz)
        local hand = "left"
        if layering == "up" then hand = "right" end
       
        if hand == "right" then
                if curx == 1 then return 0,-1 end
                if curx == -1 then return 0,1 end
                if curz == 1 then return 1,0 end
                if curz == -1 then return -1,0 end
        else
                if curx == 1 then return 0,1 end
                if curx == -1 then return 0,-1 end
                if curz == 1 then return -1,0 end
                if curz == -1 then return 1,0 end
        end
end
 
--[[Constructs a new facing to the right of the current facing
        Params: curx:number = The facing on the X axis
                        curz:number = The facing on the Z axis
                        hand:string = The hand of the axis ("right" or "left")
        Returns:number,number = the new facing on the X and Z axis after a right turn
]]--
local function getRight(curx, curz)
        local hand = "left"
        if layering == "up" then hand = "right" end
       
        if hand == "right" then
                if curx == 1 then return 0,1 end
                if curx == -1 then return 0,-1 end
                if curz == 1 then return -1,0 end
                if curz == -1 then return 1,0 end
        else
                if curx == 1 then return 0,-1 end
                if curx == -1 then return 0,1 end
                if curz == 1 then return 1,0 end
                if curz == -1 then return -1,0 end
        end
end
 
 
--[[Sends out a rednet signal requesting local printers, and will listen for any responses. Printers found are added to the
        printerList (for ID's) and printerNames (for names)
        Params: nil
        Returns:nil
]]--
local function locatePrinters()
        printerList = { }
        printerNames = { name = "Printers" }
        local oldState = state
        state = "Locating printers, please wait...   "
        drawCanvas()
        drawInterface()
        state = oldState
       
        local modemOpened = false
        for k,v in pairs(rs.getSides()) do
                if peripheral.isPresent(v) and peripheral.getType(v) == "modem" then
                        rednet.open(v)
                        modemOpened = true
                        break
                end
        end
       
        if not modemOpened then
                displayConfirmDialogue("Modem not found!", "No modem peripheral. Must have network modem to locate printers.")
                return false
        end
       
        rednet.broadcast("$3DPRINT IDENTIFY")
       
        while true do
                local id, msg = rsTimeReceive(1)
               
                if not id then break end
                if string.find(msg, "$3DPRINT IDACK") == 1 then
                        msg = string.gsub(msg, "$3DPRINT IDACK ", "")
                        table.insert(printerList, id)
                        table.insert(printerNames, msg)
                end
        end
       
        if #printerList == 0 then
                displayConfirmDialogue("Printers not found!", "No active printers found in proximity of this computer.")
                return false
        else
                return true
        end
end
 
--[[Sends a request to the printer. Waits on a response and updates the state of the application accordingly.
        Params: command:string the command to send
                        param:string a parameter to send, if any
        Returns:nil
]]--
local function sendPC(command,param)
        local msg = "$PC "..command
        if param then msg = msg.." "..param end
        rednet.send(printerList[selectedPrinter], msg)
       
        while true do
                local id,key = rsTimeReceive()
                if id == printerList[selectedPrinter] then
                        if key == "$3DPRINT ACK" then
                                break
                        elseif key == "$3DPRINT DEP" then
                                displayConfirmDialogue("Printer Empty", "The printer has exhasted a material. Please refill slot "..param..
                                        ", and click this message when ready to continue.")
                                rednet.send(printerList[selectedPrinter], msg)
                        elseif key == "$3DPRINT OOF" then
                                displayConfirmDialogue("Printer Out of Fuel", "The printer has no fuel. Please replace the material "..
                                        "in slot 1 with a fuel source, then click this message.")
                                rednet.send(printerList[selectedPrinter], "$PC SS 1")
                                id,key = rsTimeReceive()
                                rednet.send(printerList[selectedPrinter], "$PC RF")
                                id,key = rsTimeReceive()
                                rednet.send(printerList[selectedPrinter], msg)
                        end
                end
        end
       
        --Changes to position are handled after the event has been successfully completed
        if command == "FW" then
                px = px + pfx
                pz = pz + pfz
        elseif command == "BK" then
                px = px - pfx
                pz = pz - pfz
        elseif command == "UP" then
                if layering == "up" then
                        py = py + 1
                else
                        py = py - 1
                end
        elseif command == "DW" then
                if layering == "up" then
                        py = py - 1
                else    
                        py = py + 1
                end
        elseif command == "TL" then
                pfx,pfz = getLeft(pfx,pfz)
        elseif command == "TR" then
                pfx,pfz = getRight(pfx,pfz)
        elseif command == "TU" then
                pfx = -pfx
                pfz = -pfz
        end
       
        drawCanvas()
        drawInterface()
end
 
--[[A printing function that commands the printer to turn to face the desired direction, if it is not already doing so
        Params: desx:number = the normalized x direction to face
                        desz:number = the normalized z direction to face
        Returns:nil
]]--
local function turnToFace(desx,desz)
        if desx ~= 0 then
                if pfx ~= desx then
                        local temppfx,_ = getLeft(pfx,pfz)
                        if temppfx == desx then
                                sendPC("TL")
                        elseif temppfx == -desx then
                                sendPC("TR")
                        else
                                sendPC("TU")
                        end
                end
        else
                print("on the z axis")
                if pfz ~= desz then
                        local _,temppfz = getLeft(pfx,pfz)
                        if temppfz == desz then
                                sendPC("TL")
                        elseif temppfz == -desz then
                                sendPC("TR")
                        else
                                sendPC("TU")
                        end
                end
        end
end
 
--[[Performs the print
        Params: nil
        Returns:nil
]]--
local function performPrint()
        state = "active print"
        if layering == "up" then
                --An up layering starts our builder bot on the bottom left corner of our build
                px,py,pz = leflim, 0, botlim + 1
                pfx,pfz = 0,-1
               
                --We move him forward and up a bit from his original position.
                sendPC("FW")
                sendPC("UP")
                --For each layer that needs to be completed, we go up by one each time
                for layers=1,#frames do
                        --We first decide if we're going forwards or back, depending on what side we're on
                        local rowbot,rowtop,rowinc = nil,nil,nil
                        if pz == botlim then
                                rowbot,rowtop,rowinc = botlim,toplim,-1
                        else
                                rowbot,rowtop,rowinc = toplim,botlim,1
                        end
                       
                        for rows = rowbot,rowtop,rowinc do
                                --Then we decide if we're going left or right, depending on what side we're on
                                local linebot,linetop,lineinc = nil,nil,nil
                                if px == leflim then
                                        --Facing from the left side has to be easterly- it's changed here
                                        turnToFace(1,0)
                                        linebot,linetop,lineinc = leflim,riglim,1
                                else
                                        --Facing from the right side has to be westerly- it's changed here
                                        turnToFace(-1,0)
                                        linebot,linetop,lineinc = riglim,leflim,-1
                                end
                               
                                for lines = linebot,linetop,lineinc do
                                        --We move our turtle forward, placing the right material at each step
                                        local material = frames[py][pz][px]
                                        if material then
                                                material = math.log10(frames[py][pz][px])/math.log10(2) + 1
                                                sendPC("SS", material)
                                                sendPC("PD")
                                        end
                                        if lines ~= linetop then
                                                sendPC("FW")
                                        end
                                end
                               
                                --The printer then has to do a U-turn, depending on which way he's facing and
                                --which way he needs to go
                                local temppfx,temppfz = getLeft(pfx,pfz)
                                if temppfz == rowinc and rows ~= rowtop then
                                        sendPC("TL")
                                        sendPC("FW")
                                        sendPC("TL")
                                elseif temppfz == -rowinc and rows ~= rowtop then
                                        sendPC("TR")
                                        sendPC("FW")
                                        sendPC("TR")
                                end
                        end
                        --Now at the end of a run he does a 180 and moves up to begin the next part of the print
                        sendPC("TU")
                        if layers ~= #frames then
                                sendPC("UP")
                        end
                end
                --All done- now we head back to where we started.
                if px ~= leflim then
                        turnToFace(-1,0)
                        while px ~= leflim do
                                sendPC("FW")
                        end
                end
                if pz ~= botlim then
                        turnToFace(0,-1)
                        while pz ~= botlim do
                                sendPC("BK")
                        end
                end
                turnToFace(0,-1)
                sendPC("BK")
                while py > 0 do
                        sendPC("DW")
                end
        else
                --The front facing is at the top-left corner, facing south not north
                px,py,pz = leflim, botlim, 1
                pfx,pfz = 0,1
                --We move the printer to the last layer- he prints from the back forwards
                while pz < #frames do
                        sendPC("FW")
                end
               
                --For each layer in the frame we build our wall, the move back
                for layers = 1,#frames do
                        --We first decide if we're going left or right based on our position
                        local rowbot,rowtop,rowinc = nil,nil,nil
                        if px == leflim then
                                rowbot,rowtop,rowinc = leflim,riglim,1
                        else
                                rowbot,rowtop,rowinc = riglim,leflim,-1
                        end
                       
                        for rows = rowbot,rowtop,rowinc do
                                --Then we decide if we're going up or down, depending on our given altitude
                                local linebot,linetop,lineinc = nil,nil,nil
                                if py == botlim then
                                        linebot,linetop,lineinc = botlim,toplim,-1
                                else
                                        linebot,linetop,lineinc = toplim,botlim,1
                                end
                               
                                for lines = linebot,linetop,lineinc do
                                --We move our turtle up/down, placing the right material at each step
                                        local material = frames[pz][py][px]
                                        if material then
                                                material = math.log10(frames[pz][py][px])/math.log10(2) + 1
                                                sendPC("SS", material)
                                                sendPC("PF")
                                        end
                                        if lines ~= linetop then
                                                if lineinc == 1 then sendPC("DW")
                                                else sendPC("UP") end
                                        end
                                end
                                       
                                if rows ~= rowtop then
                                        turnToFace(rowinc,0)
                                        sendPC("FW")
                                        turnToFace(0,1)
                                end
                        end
                       
                        if layers ~= #frames then
                                sendPC("TU")
                                sendPC("FW")
                                sendPC("TU")
                        end
                end
                --He's easy to reset
                while px ~= leflim do
                        turnToFace(-1,0)
                        sendPC("FW")
                end
                turnToFace(0,1)
        end
       
        sendPC("DE")
       
        displayConfirmDialogue("Print complete", "The 3D print was successful.")
end
 
--[[  
                        Section: Interface  
]]--
 
--[[Runs the printing interface. Allows users to find/select a printer, the style of printing to perform and to begin the operation
        Params: none
        Returns:boolean true if printing was started, false otherwse
]]--
local function runPrintInterface()
        calculateMaterials()
        --There's nothing on canvas yet!
        if not botlim then
                displayConfirmDialogue("Cannot Print Empty Canvas", "There is nothing on canvas that "..
                                "can be printed, and the operation cannot be completed.")
                return false
        end
        --No printers nearby
        if not locatePrinters() then
                return false
        end
       
        layering = "up"
        requirementsDisplayed = false
        selectedPrinter = 1
        while true do
                drawCanvas()
                term.setBackgroundColour(colours.lightGrey)
                for i=1,10 do
                        term.setCursorPos(1,i)
                        term.clearLine()
                end
                drawInterface()
                term.setBackgroundColour(colours.lightGrey)
                term.setTextColour(colours.black)
               
                local msg = "3D Printing"
                term.setCursorPos(w/2-#msg/2 - 2, 1)
                term.write(msg)
                term.setBackgroundColour(colours.grey)
                term.setTextColour(colours.lightGrey)
                if(requirementsDisplayed) then
                        msg = "Count:"
                else
                        msg = " Slot:"
                end
                term.setCursorPos(w-3-#msg, 1)
                term.write(msg)
                term.setBackgroundColour(colours.lightGrey)
                term.setTextColour(colours.black)
               
                term.setCursorPos(7, 2)
                term.write("Layering")
                drawPictureTable(layerUpIcon, 3, 3, colours.white)
                drawPictureTable(layerForwardIcon, 12, 3, colours.white)
                if layering == "up" then
                        term.setBackgroundColour(colours.red)
                else
                        term.setBackgroundColour(colours.lightGrey)
                end
                term.setCursorPos(3, 9)
                term.write("Upwards")
                if layering == "forward" then
                        term.setBackgroundColour(colours.red)
                else
                        term.setBackgroundColour(colours.lightGrey)
                end
                term.setCursorPos(12, 9)
                term.write("Forward")
               
                term.setBackgroundColour(colours.lightGrey)
                term.setTextColour(colours.black)
                term.setCursorPos(31, 2)
                term.write("Printer ID")
                term.setCursorPos(33, 3)
                if #printerList > 1 then
                        term.setBackgroundColour(colours.grey)
                        term.setTextColour(colours.lightGrey)
                else
                        term.setTextColour(colours.red)
                end
                term.write(" "..printerNames[selectedPrinter].." ")
               
                term.setBackgroundColour(colours.grey)
                term.setTextColour(colours.lightGrey)
                term.setCursorPos(25, 10)
                term.write(" Cancel ")
                term.setCursorPos(40, 10)
                term.write(" Print ")
               
                local id, p1, p2, p3 = os.pullEvent()
               
                if id == "timer" then
                        updateTimer(p1)
                elseif id == "mouse_click" then
                        --Layering Buttons
                        if p2 >= 3 and p2 <= 9 and p3 >= 3 and p3 <= 9 then
                                layering = "up"
                        elseif p2 >= 12 and p2 <= 18 and p3 >= 3 and p3 <= 9 then
                                layering = "forward"
                        --Count/Slot
                        elseif p2 >= w - #msg - 3 and p2 <= w - 3 and p3 == 1 then
                                requirementsDisplayed = not requirementsDisplayed
                        --Printer ID
                        elseif p2 >= 33 and p2 <= 33 + #printerNames[selectedPrinter] and p3 == 3 and #printerList > 1 then
                                local chosenName = displayDropDown(33, 3, printerNames)
                                for i=1,#printerNames do
                                        if printerNames[i] == chosenName then
                                                selectedPrinter = i
                                                break;
                                        end
                                end
                        --Print and Cancel
                        elseif p2 >= 25 and p2 <= 32 and p3 == 10 then
                                break
                        elseif p2 >= 40 and p2 <= 46 and p3 == 10 then
                                rednet.send(printerList[selectedPrinter], "$3DPRINT ACTIVATE")
                                ready = false
                                while true do
                                        local id,msg = rsTimeReceive(10)
                                       
                                        if id == printerList[selectedPrinter] and msg == "$3DPRINT ACTACK" then
                                                ready = true
                                                break
                                        end
                                end
                                if ready then
                                        performPrint()
                                        break
                                else
                                        displayConfirmDialogue("Printer Didn't Respond", "The printer didn't respond to the activation command. Check to see if it's online")
                                end
                        end
                end
        end
        state = "paint"
end

--[[Performs a legacy save. When the dropdown menu is unavailable, it requests the user to save
	or exit using keyboard shortcuts rather than selecting a menu option from the dropdown.
	Pressing the control key again will cancel the save operation.
	Params: none
	Returns:string = the selection made
]]--
local function performLegacySaveExit()
	local saveMsg = "(S)ave/(E)xit?"
	if w < #saveMsg then saveMsg = "S/E?" end
	
	term.setCursorPos(1,h)
	term.setBackgroundColour(colours.lightGrey)
	term.setTextColour(colours.grey)
	term.clearLine()
	term.write(saveMsg)
	
	while true do
		local id,val = os.pullEvent()
		if id == "timer" then updateTimer(val)
		elseif id == "key" then
			if val == keys.s then return "save" 
			elseif val == keys.e then
				--Get rid of the extra event
				os.pullEvent("char")
				return "exit"
			elseif val == keys.leftCtrl then return nil
			end
		end
	end
end
 
--[[This function changes the current paint program to another tool or mode, depending on user input. Handles
        any necessary changes in logic involved in that.
        Params: mode:string = the name of the mode to change to
        Returns:nil
]]--
local function performSelection(mode)
        if not mode or mode == "" then return
       
        elseif mode == "help" and helpAvailable then
                drawHelpScreen()
               
        elseif mode == "blueprint on" then
                blueprint = true
				for i=1,#ddModes[2] do if ddModes[2][i] == "blueprint on" then
					ddModes[2][i] = "blueprint off"
				end end
               
        elseif mode == "blueprint off" then
                blueprint = false
				for i=1,#ddModes[2] do if ddModes[2][i] == "blueprint off" then
					ddModes[2][i] = "blueprint on"
				end end
               
        elseif mode == "layers on" then
                layerDisplay = true
				for i=1,#ddModes[2] do if ddModes[2][i] == "layers on" then
					ddModes[2][i] = "layers off"
				end end
       
        elseif mode == "layers off" then
                layerDisplay = false
				for i=1,#ddModes[2] do if ddModes[2][i] == "layers off" then
					ddModes[2][i] = "layers on"
				end end
       
        elseif mode == "direction on" then
                printDirection = true
				for i=1,#ddModes[2] do if ddModes[2][i] == "direction on" then
					ddModes[2][i] = "direction off"
				end end
               
        elseif mode == "direction off" then
                printDirection = false
				for i=1,#ddModes[2] do if ddModes[2][i] == "direction off" then
					ddModes[2][i] = "direction on"
				end end
		
		elseif mode == "hide interface" then
				interfaceHidden = true
			
		elseif mode == "show interface" then
				interfaceHidden = false
       
        elseif mode == "go to" then
                changeFrame()
       
        elseif mode == "remove" then
                removeFramesAfter(sFrame)
       
        elseif mode == "play" then
                playAnimation()
               
        elseif mode == "copy" then
                if selectrect and selectrect.x1 ~= selectrect.x2 then
                        copyToBuffer(false)
                end
       
        elseif mode == "cut" then
                if selectrect and selectrect.x1 ~= selectrect.x2 then
                        copyToBuffer(true)
                end
               
        elseif mode == "paste" then
                if selectrect and selectrect.x1 ~= selectrect.x2 then
                        copyFromBuffer(false)
                end
               
        elseif mode == "hide" then
                selectrect = nil
                if state == "select" then state = "corner select" end
			   
        elseif mode == "alpha to left" then
                if lSel then alphaC = lSel end
               
        elseif mode == "alpha to right" then
                if rSel then alphaC = rSel end
               
        elseif mode == "record" then
                record = not record
               
        elseif mode == "clear" then
                if state=="select" then buffer = nil
                else clearImage() end
       
        elseif mode == "select" then
                if state=="corner select" or state=="select" then
                        state = "paint"
                elseif selectrect and selectrect.x1 ~= selectrect.x2 then
                        state = "select"
                else
                        state = "corner select"
                end
               
        elseif mode == "print" then
                state = "print"
                runPrintInterface()
                state = "paint"
               
        elseif mode == "save" then
                if animated then saveNFA(sPath)
                elseif textEnabled then saveNFT(sPath)
                else saveNFP(sPath) end
               
        elseif mode == "exit" then
                isRunning = false
       
        elseif mode ~= state then state = mode
        else state = "paint"
        end
end
 
--[[The main function of the program, reads and handles all events and updates them accordingly. Mode changes,
        painting to the canvas and general selections are done here.
        Params: none
        Returns:nil
]]--
local function handleEvents()
        recttimer = os.startTimer(0.5)
        while isRunning do
                drawCanvas()
                if not interfaceHidden then drawInterface() end
               
                if state == "text" then
                        term.setCursorPos(textCurX - sx, textCurY - sy)
                        term.setCursorBlink(true)
                end
               
                local id,p1,p2,p3 = os.pullEvent()
                term.setCursorBlink(false)
                if id=="timer" then
                        updateTimer(p1)
                elseif (id=="mouse_click" or id=="mouse_drag") and not interfaceHidden then
                        if p2 >=w-1 and p3 < #column+1 then
								local off = 0
								local cansel = true
								if h < #column + 2 then
									if p3 == 1 then 
										if columnoffset > 0 then columnoffset = columnoffset-1 end
										cansel = false
									elseif p3 == h-2 then
										if columnoffset < #column-(h-4)+1 then columnoffset = columnoffset+1 end
										cansel = false
									else
										off = columnoffset - 1
									end
								end
								--This rather handily accounts for the nil case (p3+off=#column+1)
								if p1==1 and cansel then lSel = column[p3+off]
                                elseif p1==2 and cansel then rSel = column[p3+off] end
                        elseif p2 >=w-1 and p3==#column+1 then
                                if p1==1 then lSel = nil
                                else rSel = nil end
                        elseif p2==w-1 and p3==h and animated then
                                changeFrame(sFrame-1)
                        elseif p2==w and p3==h and animated then
                                changeFrame(sFrame+1)
                        elseif p2 <= #ddModes.name + 2 and p3==h and mainAvailable then
                                local sel = displayDropDown(1, h-1, ddModes)
                                performSelection(sel)
                        elseif p2 < w-1 and p3 <= h-1 then
                                if state=="pippette" then
                                        if p1==1 then
                                                if frames[sFrame][p3+sy] and frames[sFrame][p3+sy][p2+sx] then
                                                        lSel = frames[sFrame][p3+sy][p2+sx]
                                                end
                                        elseif p1==2 then
                                                if frames[sFrame][p3+sy] and frames[sFrame][p3+sy][p2+sx] then
                                                        rSel = frames[sFrame][p3+sy][p2+sx]
                                                end
                                        end
                                elseif state=="move" then
                                        updateImageLims(record)
                                        moveImage(p2,p3)
                                elseif state=="flood" then
                                        if p1 == 1 and lSel and frames[sFrame][p3+sy]  then
                                                floodFill(p2,p3,frames[sFrame][p3+sy][p2+sx],lSel)
                                        elseif p1 == 2 and rSel and frames[sFrame][p3+sy] then
                                                floodFill(p2,p3,frames[sFrame][p3+sy][p2+sx],rSel)
                                        end
                                elseif state=="corner select" then
                                        if not selectrect then
                                                selectrect = { x1=p2+sx, x2=p2+sx, y1=p3+sy, y2=p3+sy }
                                        elseif selectrect.x1 ~= p2+sx and selectrect.y1 ~= p3+sy then
                                                if p2+sx<selectrect.x1 then selectrect.x1 = p2+sx
                                                else selectrect.x2 = p2+sx end
                                               
                                                if p3+sy<selectrect.y1 then selectrect.y1 = p3+sy
                                                else selectrect.y2 = p3+sy end
                                               
                                                state = "select"
                                        end
                                elseif state=="textpaint" then
                                        local paintCol = lSel
                                        if p1 == 2 then paintCol = rSel end
                                        if frames[sFrame].textcol[p3+sy] then
                                                frames[sFrame].textcol[p3+sy][p2+sx] = paintCol
                                        end
                                elseif state=="text" then
                                        textCurX = p2 + sx
                                        textCurY = p3 + sy
                                elseif state=="select" then
                                        if p1 == 1 then
                                                local swidth = selectrect.x2 - selectrect.x1
                                                local sheight = selectrect.y2 - selectrect.y1
                                       
                                                selectrect.x1 = p2 + sx
                                                selectrect.y1 = p3 + sy
                                                selectrect.x2 = p2 + swidth + sx
                                                selectrect.y2 = p3 + sheight + sy
                                        elseif p1 == 2 and p2 < w-2 and p3 < h-1 and boxdropAvailable then
                                                inMenu = true
                                                local sel = displayDropDown(p2, p3, srModes)
                                                inMenu = false
                                                performSelection(sel)
                                        end
                                else
                                        local f,l = sFrame,sFrame
                                        if record then f,l = 1,framecount end
                                        local bwidth = 0
                                        if state == "brush" then bwidth = brushsize-1 end
                               
                                        for i=f,l do
                                                for x = math.max(1,p2+sx-bwidth),p2+sx+bwidth do
                                                        for y = math.max(1,p3+sy-bwidth), p3+sy+bwidth do
                                                                if math.abs(x - (p2+sx)) + math.abs(y - (p3+sy)) <= bwidth then
                                                                        if not frames[i][y] then frames[i][y] = {} end
                                                                        if p1==1 then frames[i][y][x] = lSel
                                                                        else frames[i][y][x] = rSel end
                                                                       
                                                                        if textEnabled then
                                                                                if not frames[i].text[y] then frames[i].text[y] = { } end
                                                                                if not frames[i].textcol[y] then frames[i].textcol[y] = { } end
                                                                        end
                                                                end
                                                        end
                                                end
                                        end
                                end
                        end
                elseif id=="char" then
                        if state=="text" then
                                if not frames[sFrame][textCurY] then frames[sFrame][textCurY] = { } end
                                if not frames[sFrame].text[textCurY] then frames[sFrame].text[textCurY] = { } end
                                if not frames[sFrame].textcol[textCurY] then frames[sFrame].textcol[textCurY] = { } end
                               
                                if rSel then frames[sFrame][textCurY][textCurX] = rSel end
                                if lSel then
                                        frames[sFrame].text[textCurY][textCurX] = p1
                                        frames[sFrame].textcol[textCurY][textCurX] = lSel
                                else
                                        frames[sFrame].text[textCurY][textCurX] = " "
                                        frames[sFrame].textcol[textCurY][textCurX] = rSel
                                end
                               
                                textCurX = textCurX+1
                                if textCurX > w + sx - 2 then sx = textCurX - w + 2 end
                        elseif tonumber(p1) then
                                if state=="brush" and tonumber(p1) > 1 then
                                        brushsize = tonumber(p1)
                                elseif animated and tonumber(p1) > 0 then
                                        changeFrame(tonumber(p1))
                                end
                        end
                elseif id=="key" then
						--All standard interface methods are locked when the interface is hidden
						if interfaceHidden then
							if p1==keys.grave then
								performSelection("show interface") 
							end
                        --Text needs special handlers (all other keyboard shortcuts are of course reserved for typing)
                        elseif state=="text" then
                                if p1==keys.backspace and textCurX > 1 then
                                        textCurX = textCurX-1
                                        if frames[sFrame].text[textCurY] then
                                                frames[sFrame].text[textCurY][textCurX] = nil
                                                frames[sFrame].textcol[textCurY][textCurX] = nil
                                        end
                                        if textCurX < sx then sx = textCurX end
                                elseif p1==keys.left and textCurX > 1 then
                                        textCurX = textCurX-1
                                        if textCurX-1 < sx then sx = textCurX-1 end
                                elseif p1==keys.right then
                                        textCurX = textCurX+1
                                        if textCurX > w + sx - 2 then sx = textCurX - w + 2 end
                                elseif p1==keys.up and textCurY > 1 then
                                        textCurY = textCurY-1
                                        if textCurY-1 < sy then sy = textCurY-1 end
                                elseif p1==keys.down then
                                        textCurY = textCurY+1
                                        if textCurY > h + sy - 1 then sy = textCurY - h + 1 end
                                end
                       
                        elseif p1==keys.leftCtrl then
                                local sel = nil
								if mainAvailable then 
									sel = displayDropDown(1, h-1, ddModes[#ddModes])
								else sel = performLegacySaveExit() end
                                performSelection(sel)
                        elseif p1==keys.leftAlt then
                                local sel = displayDropDown(1, h-1, ddModes[1])
                                performSelection(sel)
                        elseif p1==keys.h then
                                performSelection("help")
                        elseif p1==keys.x then
                                performSelection("cut")
                        elseif p1==keys.c then
                                performSelection("copy")
                        elseif p1==keys.v then
                                performSelection("paste")
                        elseif p1==keys.z then
                                performSelection("clear")
                        elseif p1==keys.s then
                                performSelection("select")
                        elseif p1==keys.tab then
                                performSelection("hide")
                        elseif p1==keys.q then
                                performSelection("alpha to left")
                        elseif p1==keys.w then
                                performSelection("alpha to right")
                        elseif p1==keys.f then
                                performSelection("flood")
                        elseif p1==keys.b then
                                performSelection("brush")
                        elseif p1==keys.m then
                                performSelection("move")
                        elseif p1==keys.backslash and animated then
                                performSelection("record")
                        elseif p1==keys.p then
                                performSelection("pippette")
                        elseif p1==keys.g and animated then
                                performSelection("go to")
						elseif p1==keys.grave then 
								performSelection("hide interface")
                        elseif p1==keys.period and animated then
                                changeFrame(sFrame+1)
                        elseif p1==keys.comma and animated then
                                changeFrame(sFrame-1)
                        elseif p1==keys.r and animated then
                                performSelection("remove")
                        elseif p1==keys.space and animated then
                                performSelection("play")
                        elseif p1==keys.t and textEnabled then
                                performSelection("text")
                                sleep(0.01)
                        elseif p1==keys.y and textEnabled then
                                performSelection("textpaint")
                        elseif p1==keys.left then
                                if state == "move" and toplim then
                                        updateImageLims(record)
                                        if toplim and leflim then
                                                moveImage(leflim-1,toplim)
                                        end
                                elseif state=="select" and selectrect.x1 > 1 then
                                        selectrect.x1 = selectrect.x1-1
                                        selectrect.x2 = selectrect.x2-1
                                elseif sx > 0 then sx=sx-1 end
                        elseif p1==keys.right then
                                if state == "move" then
                                        updateImageLims(record)
                                        if toplim and leflim then
                                                moveImage(leflim+1,toplim)
                                        end
                                elseif state=="select" then
                                        selectrect.x1 = selectrect.x1+1
                                        selectrect.x2 = selectrect.x2+1
                                else sx=sx+1 end
                        elseif p1==keys.up then
                                if state == "move" then
                                        updateImageLims(record)
                                        if toplim and leflim then
                                                moveImage(leflim,toplim-1)
                                        end
                                elseif state=="select" and selectrect.y1 > 1 then
                                        selectrect.y1 = selectrect.y1-1
                                        selectrect.y2 = selectrect.y2-1
                                elseif sy > 0 then sy=sy-1 end
                        elseif p1==keys.down then
                                if state == "move" then
                                        updateImageLims(record)
                                        if toplim and leflim then
                                                moveImage(leflim,toplim+1)
                                        end
                                elseif state=="select" then
                                        selectrect.y1 = selectrect.y1+1
                                        selectrect.y2 = selectrect.y2+1
                                else sy=sy+1 end
                        end
                end
        end
end
 
--[[
                        Section: Main  
]]--
 
--The first thing done is deciding what features we actually have, given the screen size
if w < 7 or h < 4 then
	--NPaintPro simply doesn't work at certain configurations
	shell.run("clear")
	print("Screen too small")
	os.pullEvent("key")
	return
end
--And reduces the number of features in others.
determineAvailableServices()
 
--There is no b&w support for NPP.
if not term.isColour() then
	shell.run("clear")
	print("NPaintPro\nBy NitrogenFingers\n\nNPaintPro can only be run on advanced "..
	"computers. Please reinstall on an advanced computer.")
    return
end
 
--Taken almost directly from edit (for consistency)
local tArgs = {...}
 
--Command line options can appear before the file path to specify the file format
local ca = 1
while ca <= #tArgs do
	if tArgs[ca] == "-a" then animated = true
	elseif tArgs[ca] == "-t" then textEnabled = true
	elseif tArgs[ca] == "-d" then interfaceHidden = true
	elseif string.sub(tArgs[ca], 1, 1) == "-" then
		print("Unrecognized option: "..tArgs[ca])
		return
	else break end
	ca = ca + 1
end

--Presently, animations and text files are not supported
if animated and textEnabled then
    print("No support for animated text files- cannot have both -a and -t")
	return
end

--Filepaths must be added if the screen is too small
if #tArgs < ca then
	if not filemakerAvailable then
		print("Usage: npaintpro [-a,-t,-d] <path>")
		return
	else
		--Otherwise do the logo draw early, to determine the file.
		drawLogo()
		if not runFileMaker() then return end
	end
else
	if not interfaceHidden then drawLogo() end
	sPath = shell.resolve(tArgs[ca])
end
 
if fs.exists(sPath) then
        if fs.isDir(sPath) then
                print("Cannot edit a directory.")
                return
        elseif string.find(sPath, ".nfp") ~= #sPath-3 and string.find(sPath, ".nfa") ~= #sPath-3 and
                        string.find(sPath, ".nft") ~= #sPath-3 then
                print("Can only edit .nfp, .nft and .nfa files:",string.find(sPath, ".nfp"),#sPath-3)
                return
        end
       
        if string.find(sPath, ".nfa") == #sPath-3 then
                animated = true
        end
       
        if string.find(sPath, ".nft") == #sPath-3 then
                textEnabled = true
        end    
       
        if string.find(sPath, ".nfp") == #sPath-3 and animated then
                print("Convert to nfa? Y/N")
                if string.find(string.lower(io.read()), "y") then
                        local nsPath = string.sub(sPath, 1, #sPath-1).."a"
                        fs.move(sPath, nsPath)
                        sPath = nsPath
                else
                        animated = false
                end
        end
       
        --Again this is possible, I just haven't done it. Maybe I will?
        if textEnabled and (string.find(sPath, ".nfp") == #sPath-3 or string.find(sPath, ".nfa") == #sPath-3) then
                print("Cannot convert to nft")
        end
else
        if not animated and not textEnabled and string.find(sPath, ".nfp") ~= #sPath-3 then
                sPath = sPath..".nfp"
        elseif animated and string.find(sPath, ".nfa") ~= #sPath-3 then
                sPath = sPath..".nfa"
        elseif textEnabled and string.find(sPath, ".nft") ~= #sPath-3 then
                sPath = sPath..".nft"
        end
end
 
init()
handleEvents()
 
term.setBackgroundColour(colours.black)
plocha ()