--[[
 nft extra functions
 pastebin get J11BaaDy nfte 

list of extra functions:
 nft.flipY(table image) 
	returns 'image' stretched vertically
 nft.flipX(table image)
	returns 'image' stretched horizontally
 nft.grayOut(table image)
	converts 'image' to grayscale
 nft.lighten(table image)
	returns 'image' but with brighter colors, suitable for transitions
 nft.darken(table image)
	returns 'image' but with darker colors, suitable for transitions
 nft.getSize(table image)
	returns the x and y sizes of 'image'
 nft.stretchImage(table image, number stretchedX, number stretchedY)
	returns 'image', but stretched to fit sizes 'stretchedX' and 'stretchedY'.
 nft.merge(table {image1,x,y}, table {image2,x,y}, ...)
	returns an image composed of image1 layered upon image2 layered upon image3 and so on.
 nft.fullScreen(number color, terminal object)
	returns a fullscreen picture made solidly of 'color'. sets size to current terminal or 'object' if defined.
 nft.unloadImage(table image)
	returns a string NFP picture made from 'image'.
 nft.autocrop(table image)
	returns 'image' but with the blank space cut off from the left and top.
 nft.drawImageBlit(table image, number x, number y)
	draws 'image' at 'x' and 'y' using term.blit. As such, it does not support transparency. You will want to merge images together before rendering.
 nft.drawImageBlitCenter(table image, number x, number y, terminal object)
 	draws 'image' centered around 'x' and 'y'. if 'x' and 'y' aren't defined, they default to half the screen width and height respectively. 'object' can be defined to use its screen size instead.
 nft.centerWithBlankSpace(table image, number x, number y, terminal object)
	returns 'image', but with extra blank space to center it to 'x' and 'y'. if 'x' and 'y' aren't defined, they default to half the screen width and height respectively. 'object' can be defined to use its screen size instead.
--]]

local explode = function(div,str)
    if (div=='') then return false end
    local pos,arr = 0,{}
    for st,sp in function() return string.find(str,div,pos,true) end do
        arr[#arr+1] = str:sub(pos,st-1)
        pos = sp + 1
    end
    arr[#arr+1] = str:sub(pos)
    return arr
end
local blitcolors = {
	[" "] = allowZero and 0 or nil,
	["0"] = colors.white,
	["1"] = colors.orange,
	["2"] = colors.magenta,
	["3"] = colors.lightBlue,
	["4"] = colors.yellow,
	["5"] = colors.lime,
	["6"] = colors.pink,
	["7"] = colors.gray,
	["8"] = colors.lightGray,
	["9"] = colors.cyan,
	["a"] = colors.purple,
	["b"] = colors.blue,
	["c"] = colors.brown,
	["d"] = colors.green,
	["e"] = colors.red,
	["f"] = colors.black,
}
local BTC = function(_color,allowZero) --Blit To Color
	if _color == nil then return nil end
	return blitcolors[_color]
end

local importFromNFT = function(input)
	local tinput = explode("\n",input)
	local tcol,bcol
	local cx --represents the x position in the picture
	local sx --represents the x position in the file
	local charoutput,txtoutput,bgoutput = {}
	for y = 1, #tinput do
		charoutput[y], txtoutput[y], bgoutput[y] = {}, {}, {}
		tcol,bcol = colors.white,colors.black
		cx, sx = 1, 0
		while sx < #tinput[y] do
			sx = sx + 1
			if tinput[y]:sub(sx,sx) == "\30" then
				bcol = BTC(tinput[y]:sub(sx+1,sx+1))
				sx = sx + 1
			elseif tinput[y]:sub(sx,sx) == "\31" then
				tcol = BTC(tinput[y]:sub(sx+1,sx+1))
				sx = sx + 1
			else
				if tcol and bcol then
					charoutput[y][cx] = tinput[y]:sub(sx,sx)
					txtoutput[y][cx] = tcol
					bgoutput[y][cx] = bcol
				end
				cx = cx + 1
			end
		end
	end
	return charoutput, txtoutput, bgoutput
end

local exportToNFT = function(charinput, txtinput, bginput)
	local input = {}
	for y = 1, #bginput do
		for x = 1, #bginput[y] do
			input[#input+1] = {
				x = x,
				y = y,
				b = bginput[y][x],
				t = txtinput[y][x],
				c = charinput[y][x],
			}
		end
	end
    local doop = {}
	local p = input
	local pheight = 0
	local pwidth = 0
    local nftoutput = "\30 \31f"
	for a = 1, #p do
		if p[a].y > pheight then
			pheight = p[a].y
		end
		if p[a].x > pwidth then
			pwidth = p[a].x
		end
	end
	for k,v in pairs(p) do
		if not doop[v.y] then doop[v.y] = {} end
        doop[v.y][v.x] = {}
        doop[v.y][v.x]["char"] = v.c
        doop[v.y][v.x]["text"] = CTB(v.t) or " "
		doop[v.y][v.x]["back"] = CTB(v.b) or " "
	end
	for y = 1, pheight do
		if doop[y] then
			for x = 1, pwidth do
                local nWriteBackground
                local nWriteColor
				if doop[y][x] then
                    if doop[y][x]["back"] ~= nWriteBackground then
                        nWriteBackground = b
                        nftoutput = nftoutput.."\30"..doop[y][x]["back"]
                    end
                    if doop[y][x]["text"] ~= nWriteColor then
                        nWriteColor = c
                        nftoutput = nftoutput.."\31"..doop[y][x]["text"]
                    end
					nftoutput = nftoutput..doop[y][x]["char"]
					if (not doop[y][x+1]) and x ~= pwidth then
                        nftoutput = nftoutput.."\30".." "
					end
				else
					nftoutput = nftoutput.." "
				end
			end
		end
		if y ~= pheight then
			nftoutput = nftoutput.."\n\30 \31f"
		end
	end
	return nftoutput
end

local round = function(x) return x + 0.5 - (x + 0.5) % 1 end
local deepCopy = function(tbl) return {table.unpack(tbl)} end
local bcol, ccol = {
[0]=" ",[colors.white]="0",[colors.orange]="1",[colors.magenta]="2",[colors.lightBlue]="3",[colors.yellow]="4",[colors.lime]="5",[colors.pink]="6",[colors.gray]="7",[colors.lightGray]="8",[colors.cyan]="9",[colors.purple]="a",[colors.blue]="b",[colors.brown]="c",[colors.green]="d",[colors.red]="e",[colors.black]="f"}, {}
for k,v in pairs(bcol) do ccol[v] = k end
local flipY = function(image)
	local output = {}
	for y = #image, 1, -1 do output[#output+1] = image[y] end
	return output
end
nft.flipY = funtion(image)
	local c,t,b = importFromNFT(image)
	return exportToNFT(flipY(c),flipY(t),flipY(b))
end

local flipX = function(image)
	local output,sizeX = {}, 0
	for y = 1, #image do sizeX = math.max(sizeX,#image[y]) end
	for y = 1, #image do
		output[y] = {}
		for x = 1, sizeX do output[y][x] = deepCopy(image)[y][sizeX-(x-1)] or 0 end
	end
	return output
end
nft.flipX = function(image)
	local c,t,b = importFromNFT(image)
	return exportToNFT(flipX(c),flipX(t),flipX(b))
end

local grayOut = function(image)
	local output,grays = {},{[0] = 0,[colors.white]=colors.white,[colors.orange]=colors.lightGray,[colors.magenta]=colors.lightGray,[colors.lightBlue]=colors.lightGray,[colors.yellow]=colors.white,[colors.lime]=colors.lightGray,[colors.pink]=colors.lightGray,[colors.gray]=colors.gray,[colors.lightGray]=colors.lightGray,[colors.cyan]=colors.lightGray,[colors.purple]=colors.gray,[colors.blue]=colors.gray,[colors.brown]=colors.gray,[colors.green]=colors.lightGray,[colors.red]=colors.gray,[colors.black]=colors.black}
	for y = 1, #image do
		output[y] = {}
		for x = 1, #image[y] do output[y][x] = grays[image[y][x]] or image[y][x] end
	end
	return output
end
nft.grayOut = function(image)
	local c,t,b = importFromNFT(image)
	return exportToNFT(grayOut(c),grayOut(t),grayOut(b))
end

local lighten = function(image)
	local output,lighters = {},{[0] = 0,[colors.white] = colors.white,[colors.orange] = colors.yellow,[colors.magenta] = colors.pink,[colors.lightBlue] = colors.white,[colors.yellow] = colors.white,[colors.lime] = colors.white,[colors.pink] = colors.white,[colors.gray] = colors.lightGray,[colors.lightGray] = colors.white,[colors.cyan] = colors.lightBlue,[colors.purple] = colors.magenta,[colors.blue] = colors.lightBlue,[colors.brown] = colors.orange,[colors.green] = colors.lime,[colors.red] = colors.magenta,[colors.black] = colors.gray}
	for y = 1, #image do
		output[y] = {}
		for x = 1, #image[y] do output[y][x] = lighters[image[y][x]] or image[y][x] end
	end
	return output
end
nft.lighten = function(image)
	local c,t,b = importFromNFT(image)
	return exportToNFT(lighten(c),lighten(t),lighten(b))
end

local darken = function(image)
	local output, darkers = {},{[0]=0,[colors.white]=colors.lightGray,[colors.orange]=colors.brown,[colors.magenta]=colors.purple,[colors.lightBlue]=colors.cyan,[colors.yellow]=colors.orange,[colors.lime]=colors.green,[colors.pink]=colors.magenta,[colors.gray]=colors.black,[colors.lightGray]=colors.gray,[colors.cyan]=colors.blue,[colors.purple]=colors.gray,[colors.blue]=colors.gray,[colors.brown]=colors.black,[colors.green]=colors.gray,[colors.red]=colors.gray,[colors.black]=colors.black}
	for y = 1, #image do
		output[y] = {}
		for x = 1, #image[y] do output[y][x] = darkers[image[y][x]] or image[y][x] end
	end
	return output
end
nft.darken = function(image)
	local c,t,b = importFromNFT(image)
	return exportToNFT(darken(c),darken(t),darken(b))
end

nft.getSize = function(nimage)
	local image = importFromNFT(nimage)
	local xsize = 0
	if type(image) ~= "table" then return 0,0 end
	for y = 1, #image do xsize = math.max(xsize,#image[y]) end
	return xsize, #image
end

local stretchImage = function(_image,sx,sy)
	local image,output = deepCopy(_image), {}
	if sx == 0 or sy == 0 then return {{}} end
	if sx < 0 then image = nft.flipX(image) end
	if sy < 0 then image = nft.flipY(image) end
	sx,sy = round(math.abs(sx)), round(math.abs(sy))
	if sx == 0 or sy == 0 then return {{}} end
	local imX,imY = nft.getSize(image)
	local xcur,ycur
	for y = 1, sy do
		output[y] = {}
		for x = 1, sx do
			output[y][x] = image[math.max(1,round((y/sy)*imY))][math.max(1,round((x/sx)*imX))] or nil
		end
	end
	return output
end
nft.stretchImage = function(image,sx,sy)
	local c,t,b = importFromNFT(image)
	return exportToNFT(stretchImage(c,sx,sy),stretchImage(t,sx,sy),stretchImage(b,sx,sy))
end

nft.drawImageBlit = function(image,ix,iy)
	if (type(ix) ~= "number") or (type(iy) ~= "number") then
		error("Expected image, x, y", 2)
	else
		local c,t,b = importFromNFT(image)
		ix, iy = round(ix), round(iy)
		local buffc,bufft,buffb
		for y = 1, #image do
			buffc,bufft,buffb = "","",""
			for x = 1, #image[y] do
				buffc = buffc..bcol[c[y][x]]
				bufft = bufft..bcol[t[y][x]]
				buffb = buffb..bcol[b[y][x]]
			end
			term.setCursorPos(ix,iy+(y-1))
			term.blit(buffc,bufft,buffb)
		end
	end
end

local centerWithBlankSpace = function(_image,ix,iy,object)
	local image,scX,scY = deepCopy(_image)
	if object then scX,scY = object.getSize() else scX,scY = term.getSize() end
	local imgXsize,imgYsize = paintutils.getSize(image)
	if imgXsize == 0 or imgYsize == 0 then return {{}} end
	local incX,incY = math.floor((ix or (scX/2)) - (imgXsize/2)), math.floor((iy or (scY/2)) - (imgYsize/2))
	local output = {}
	for y = 1, imgYsize + incY do
		output[y] = {}
		for x = 1, imgXsize + incX do
			if (x > incX) and (y > incY) then
				output[y][x] = image[y-incY][x-incX] or 0
			else
				output[y][x] = 0
			end
		end
	end
	return output
end
nft.centerWithBlankSpace = function(image,ix,iy,object)
	local c,t,b = importFromNFT(image)
	return exportToNFT(centerWithBlankSpace(c,ix,iy,object),centerWithBlankSpace(t,ix,iy,object),centerWithBlankSpace(b,ix,iy,object))
end

nft.drawImageBlitCenter = function(image,ix,iy,object)
	local scX,scY
	if object then scX,scY = object.getSize() else scX,scY = term.getSize() end
	local imgXsize,imgYsize = nft.getSize(image)
	return nft.drawImageBlit(image, (ix or (scX/2)) - (imgXsize/2), (iy or (scY/2)) - (imgYsize/2))
end

local merge = function(...)
	local output,arg,imgXsize,imgYsize,image,xdiff,ydiff = {}, table.pack(...), 0, 0
	for a = 1, #arg do
		local x,y = nft.getSize(arg[a][1])
		if not (x == 0 or y == 0) then
			x, y = x+arg[a][2], y+arg[a][3]
			imgXsize = math.max(imgXsize,x)
			imgYsize = math.max(imgYsize,y)
		end
	end
	for a = #arg, 1, -1 do
		image,xdiff,ydiff = table.unpack(arg[a])
		xdiff, ydiff = xdiff - 1, ydiff - 1
		for y = 1, imgYsize do
			output[y] = output[y] or {}
			for x = 1, imgXsize do
				output[y][x] = output[y][x] or 0
				if image[y-ydiff] then
					if image[y-ydiff][x-xdiff] and (image[y-ydiff][x-xdiff] ~= 0) then
						output[y][x] = image[y-ydiff][x-xdiff]
					end
				end
			end
		end
	end
	return output
end
nft.merge = function(...)
	--uuhhhh
end
nft.fullScreen = function(bgcol,object)
	local scr_x,scr_y = (object or term).getSize()
	local output,l = {},{}
	bgcol = bgcol or colors.black
	for x = 1, scr_x do l[x] = bgcol end
	for y = 1, scr_y do output[y] = l end
	return output
end
nft.unloadImage = function(image)
	local output = ""
	for y = 1, #image do
		for x = 1, #image[y] do output = output..bcol[image[y][x]] end
		if y < #image then output = output.."\n" end
	end
	return output
end
nft.autocrop = function(image)
	local output,top,leftings = {},1,{}
	local isTopped = false
	for a = 1, #image do
		if (not isTopped) and (#image[a] > 0) then
			top = a
			isTopped = true
		end
		if isTopped then
			output[#output+1] = deepCopy(image[a])
		end
	end
	for y = 1, #output do
		leftings[y] = 0
		for x = 1, #output[y] do
			if (output[y][x] == 0) or (output[y][x] == nil) then
				leftings[y] = leftings[y] + 1
			else
				break
			end
		end
	end
	local left = math.min(table.unpack(leftings))
	for y = 1, #output do
		for l = 1, left do table.remove(output[y],1) end
	end
	return output
end