Edit++ Pastebin Edition

local w, h = term.getSize()
local lChanged = false
local pChanged = true
local mChanged = true
local numlength = 1
local type = 1
local tabNum = 0
local mode = "edit"
local clickStart, clickEnd, prevline, currentLine, currentPos
local cTables, cComTab, program, colTab = {}, {}, {}, {}
cParTab = {}
if mode == "edit" then
    colTab[1] = colors.lightGray
    colTab[2] = colors.green
    colTab[3] = colors.red
    colTab[4] = colors.orange
    colTab[5] = colors.lightBlue
    colTab[6] = colors.white
elseif mode == "read" then
    colTab[1] = colors.white
    colTab[2] = colors.white
    colTab[3] = colors.white
    colTab[4] = colors.white
    colTab[5] = colors.white
    colTab[6] = colors.white
end
local location = {
    ["x"] = 1,
    ["y"] = 1
}
local position = {
    ["x"] = 1,
    ["y"] = 1
}
local conditionals = {
    ["if"] = {"end", colors.red, colors.pink},
    ["while"] = {"end", colors.red, colors.pink},
    ["for"] = {"end", colors.red, colors.pink},
    ["function"] = {"end", colors.red, colors.pink}
}
local keywords = {
    ["if"] = colors.yellow,
    ["then"] = colors.yellow,
    ["else"] = colors.yellow,
    ["elseif"] = colors.yellow,
    ["end"] = colors.yellow,
    ["function"] = colors.yellow,
    ["while"] = colors.yellow,
    ["for"] = colors.yellow,
    ["in"] = colors.yellow,
    ["do"] = colors.yellow,
    ["local"] = colors.yellow,
    ["repeat"] = colors.yellow,
    ["until"] = colors.yellow,
    ["next"] = colors.yellow,
    ["and"] = colors.orange,
    ["or"] = colors.orange,
    ["not"] = colors.orange,
    ["true"] = colors.orange,
    ["false"] = colors.orange,
    ["nil"] = colors.gray,
    ["break"] = colors.purple,
    ["return"] = colors.purple,
    ["print"] = colors.pink,
    ["write"] = colors.pink,
    ["pairs"] = colors.pink,
    ["ipairs"] = colors.pink,
    ["type"] = colors.blue,
    ["tostring"] = colors.blue,
    ["tonumber"] = colors.blue,
    ["assert"] = colors.blue,
    ["setmetatable"] = colors.blue
}

local function draw(string, xPos, yPos, txtcol, bakcol)
    local string = string or ""
    local txtcol = txtcol or colors.white
    local bakcol = bakcol or colors.black
    term.setCursorPos(xPos, yPos)
    term.setBackgroundColor(bakcol)
    term.setTextColor(txtcol)
    term.write(string)
end

local function codeDraw(string, xPos, yPos)
    local string = string or ""
    local xPos = xPos - location["x"] + 1
    local sStart, sEnd = 1, 1 + w - numlength
    local tabDraw = true
    local multiComment = false
    while #string > 0 and xPos <= sEnd do
        --[[for i in pairs(cComTab) do
            if mode == "edit" then
                if not multiComment and (yPos-1 == cComTab[i][1][2]-location["y"] + 1 and xPos-3 >= cComTab[i][1][1]-location["x"] + 1) or (yPos-1 == cComTab[i][2][2]-location["y"]+1 and xPos-2 <= cComTab[i][2][1]-location["x"]+1) or (yPos-1 > cComTab[i][1][2]-location["y"]+1 and yPos-1 < cComTab[i][2][2]-location["y"]+1) then
                    colTab[1] = colors.green
                    colTab[2] = colors.green
                    colTab[3] = colors.green
                    colTab[4] = colors.green
                    colTab[5] = colors.green
                    colTab[6] = colors.green
                    multiComment = true
                    break
                elseif multiComment then
                    colTab[1] = colors.lightGray
                    colTab[2] = colors.green
                    colTab[3] = colors.red
                    colTab[4] = colors.orange
                    colTab[5] = colors.lightBlue
                    colTab[6] = colors.white
                    multiComment = false
                end
            end
        end]]--
        if string:find("^%$___") then
            local _, en = string:find("^%$___")
            if en >= sStart and xPos <= sEnd then
                if tabDraw and not multiComment then
                    draw("   |", xPos, yPos, colTab[1], colors.black)
                else
                    draw("    ", xPos, yPos, colTab[1], colors.black)
                end
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^%-%-.*") then
            tabDraw = false
            local _, en = string:find("^%-%-.*")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[2], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^\".-[^\\]\"") then
            tabDraw = false
            local _, en = string:find("^\".-[^\\]\"")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[3], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^\'.-[^\\]\'") then
            tabDraw = false
            local _, en = string:find("^\'.-[^\\]\'")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[3], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^\"\"") then
            tabDraw = false
            local _, en = string:find("^\"\"")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[3], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^\'\'") then
            tabDraw = false
            local _, en = string:find("^\'\'")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[3], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^%[%[.-%]%]") then
            tabDraw = false
            local _, en = string:find("^%[%[.-%]%]")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[3], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^%d+") then
            tabDraw = false
            local _, en = string:find("^%d+")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[4], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^%p") then
            tabDraw = false
            local _, en = string:find("^%p")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[5], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^[%a_]+") then
            tabDraw = false
            local _, en = string:find("^[%a_]+")
            local test = string:sub(1, en)
            local color = colors.white
            if keywords[test] and mode == "edit" then
                color = keywords[test]
            end
            if multiComment then
                color = colors.green
            end
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, color, colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        elseif string:find("^[^%w_]") then
            tabDraw = false
            local _, en = string:find("^[^%w_]")
            if en >= sStart and xPos <= sEnd then
                draw(string:sub(1, en), xPos, yPos, colTab[6], colors.black)
            end
            string = string:sub(en + 1)
            xPos = xPos + en
        end
    end
end

local function printMenu()
    term.setCursorPos(1, 1)
    term.setBackgroundColor(colors.lightGray)
    term.clearLine()
    draw("Press CTRL for menu...", 1, 1, colors.gray, colors.lightGray)
end

local function saveFile(codeTable, filename)
    local tempFile = {}
    for i, v in ipairs(codeTable) do
        tempFile[i] = v:gsub("$___", "    ")
    end
    local sFile = fs.open(filename, "w")
    for _, v in ipairs(tempFile) do
        sFile.writeLine(v)
    end
    sFile.close()
end

local function showProgram()
    multiComment = false
    numlength = #tostring(#program - location["y"] + 1 >= h and location["y"] + h - 1  or #program)
    for y = location["y"], #program - location["y"] + 1 >= h - 1 and location["y"] + h - 2  or #program do
        codeDraw(program[y], 1 + numlength, y - location["y"] + 2)
    end
end

local function showProgramLine(line)
    numlength = #tostring(#program - location["y"] + 1 >= h and location["y"] + h - 1  or #program)
    codeDraw(program[line], 1 + numlength, line - location["y"] + 2)
end

local function showNumbers()
    local activeLoops = {}
    local up, down
    for _, v in pairs(cTables) do
        if currentLine >= v[1] and currentLine <= v[2] then
            activeLoops[#activeLoops + 1] = {v[1], v[2]}
        end
    end
    if #activeLoops > 0 then
        local key, mini = 0, #program
        for i, v in pairs(activeLoops) do
            if v[2] - v[1] < mini then
                key, mini = i, v[2] - v[1]
            end
        end
        if key > 0 then
            up, down = activeLoops[key][1], activeLoops[key][2]
        end
    end
    for y = location["y"], #program - location["y"] + 1 >= h - 1 and location["y"] + h - 2  or #program do
        local text, back = colors.gray, colors.lightGray
        if up and down and y > up and y < down then
            text, back = colors.red, colors.pink
        elseif up and down and (y == up or y == down) then
            text, back = colors.pink, colors.red
        end
        draw(tostring(y), 1, y - location["y"] + 2, text, back)
        if #tostring(y) < numlength then
            write(" ")
        end
    end
end

local function addLetter(char, str, pos)
    return str:sub(0, pos - 1) .. tostring(char) .. str:sub(pos)
end

local function removeLetter(str, pos)
    return str:sub(0, pos) .. str:sub(pos + 2)
end

local function fixCursorPos()
    if position["y"] < 1 then
        pChanged = true
        location["y"] = location["y"] + position["y"] - 1
        position["y"] = 1
    elseif position["y"] > h - 1 then
        pChanged = true
        location["y"] = location["y"] + position["y"] - (h-1)
        position["y"] = h - 1
    end
    if location["y"] < 1 then
        pChanged = false
        location["y"] = 1
    elseif location["y"] + h - 1 > #program then
        pChanged = false
        location["y"] = #program - h + 1
    end
    local dollarNum
    if program[location["y"] + position["y"] - 1]:sub(location["x"] + position["x"] - 1, location["x"] + position["x"] - 1) == "_" then
        for i = 1, 3 do
        if program[location["y"] + position["y"] - 1]:sub(location["x"] + position["x"] - 1 - i, location["x"] + position["x"] - 1 - i) ~= "_" then
                if program[location["y"] + position["y"] - 1]:sub(location["x"] + position["x"] - 1 - i, location["x"] + position["x"] - 1 - i) == "$" then
                    dollarNum = i
                    break
                end
                break
            end
        end
        if dollarNum and dollarNum < 3 then
            for i = 1, 3 - dollarNum do
                if program[location["y"] + position["y"] - 1]:sub(location["x"] + position["x"] - 1 + i, location["x"] + position["x"] - 1 + i) ~= "_" then
                    dollarNum = nil
                    break
                end
            end
        end
        if dollarNum then
            position["x"] = position["x"] - numlength - dollarNum + 2
        end
    end
    if position["x"] + location["x"] - 1 > #program[position["y"] + location["y"] - 1] then
        position["x"] = #program[position["y"] + location["y"] - 1] - location["x"] + 2
    end
    if position["x"] < 1 then
        pChanged = true
        location["x"] = location["x"] + position["x"] - 1
        position["x"] = 1
    elseif position["x"] > w - numlength then
        pChanged = true
        location["x"] = location["x"] + position["x"] - (w-numlength)
        position["x"] = w - numlength
    end
    if location["x"] < 1 then
        pChanged = false
        location["x"] = 1
    elseif location["x"] + w - numlength > #program then
        pChanged = false
        location["x"] = #program - w + numlength
    end
    if mode == "read" and location["x"] < 3 then
        location["x"] = 3
    elseif mode == "edit" and location["x"] < 1 then
        location["x"] = 1
    end
    currentLine = location["y"] + position["y"] - 1
    currentPos = position["x"] + location["x"] - 1
end

term.setCursorBlink(true)
while true do
    if mode == "edit" then
        numlength = #tostring(#program - location["y"] + 1 >= h and location["y"] + h - 1  or #program)
    elseif mode == "read" then
        numlength = 0
    end
    fixCursorPos()
    --cComTab = checkMultiComments()
    if pChanged or program[currentLine]:sub(currentPos - 2, currentPos - 1) == "]]" then
        --cTables = checkConditionals()
        term.setBackgroundColor(colors.black)
        term.clear()
        showProgram()
        pChanged = false
        lChanged = false
    elseif lChanged then
        --cTables = checkConditionals()
        term.setBackgroundColor(colors.black)
        term.clearLine()
        showProgramLine(currentLine)
        lChanged = false
    end
    if mChanged then
        printMenu()
        mChanged = false
    end
    --[[if prevline then
        showProgramLine(prevline[1])
        showProgramLine(prevline[2])
        prevline = nil
    end
    if mode == "edit" then
        cParTab = checkParenthesis()
    end
    for i, v in pairs(cParTab) do
        if (currentPos == cParTab[i][1] and currentLine == cParTab[i][2]) or (currentPos == cParTab[i][3] and currentLine == cParTab[i][4]) then
            draw(cParTab[i][5], cParTab[i][1] + numlength - location["x"] + 1, cParTab[i][2] - location["y"] + 2, colors.blue, colors.lightBlue)
            draw(cParTab[i][6], cParTab[i][3] + numlength - location["x"] + 1, cParTab[i][4] - location["y"] + 2, colors.blue, colors.lightBlue)
            prevline = {cParTab[i][2], cParTab[i][4]}
        end
    end]]
    if mode == "edit" then
        showNumbers()
    end
    term.setTextColor(colors.white)
    term.setCursorPos(position["x"] + numlength, position["y"] + 1)
    local events = {os.pullEvent()}
    if events[1] == "char" and mode == "edit" then
        lChanged = true
        program[currentLine] = addLetter(events[2], program[currentLine], position["x"] + location["x"] - 1)
        position["x"] = position["x"] + 1
    elseif events[1] == "key" then
        if events[2] == keys.up then   --^
                position["y"] = position["y"] - 1
        elseif events[2] == keys.down then   --v
                position["y"] = position["y"] + 1
        elseif events[2] == keys.right then   -->
            if (position["x"] + location["x"] - 1) % 4 == 1 and position["x"] + location["x"] - 1 < #program[currentLine] and program[currentLine]:sub(position["x"] + location["x"] - 1, position["x"] + location["x"] + 2) == "$___" then
                position["x"] = position["x"] + 4
            elseif currentLine < #program and currentPos > #program[currentLine] then
                position["x"] = 1 - location["x"] + 1
                position["y"] = position["y"] + 1
            else
                position["x"] = position["x"] + 1
            end
        elseif events[2] == keys.left then   --<
            if (position["x"] + location["x"] - 1) % 4 == 1 and position["x"] + location["x"] - 1 > 4 and program[currentLine]:sub(position["x"] + location["x"] - 5, position["x"] + location["x"] - 2) == "$___" then
                position["x"] = position["x"] - 4
            elseif currentLine > 1 and currentPos == 1 then
                position["x"] = #program[currentLine - 1] + 1
                position["y"] = position["y"] - 1
            else
                position["x"] = position["x"] - 1
            end
        end
        if events[2] == keys.backspace and mode == "edit" then
            lChanged = true
            if (position["x"] + location["x"] - 1) % 4 == 1 and position["x"] + location["x"] - 1 > 4 and program[currentLine]:sub(position["x"] + location["x"] - 5, position["x"] + location["x"] - 2) == "$___"  then
                for i = 1, 4 do
                    program[currentLine] = removeLetter(program[currentLine], location["x"] + position["x"] - 6)
                    position["x"] = position["x"] - 4
                end
            elseif currentLine > 1 and currentPos == 1 then
                position["y"] = position["y"] - 1
                location["x"] = (location["x"] > #program[currentLine - 1] or location["x"] + w - #tostring(currentLine - 1) < #program[currentLine - 1]) and #program[currentLine - 1] + 1 or location["x"]
                position["x"] = #program[currentLine - 1] - location["x"] + 2
                program[currentLine - 1] = program[currentLine - 1] .. (table.remove(program, currentLine))
                pChanged = true
                        else
                program[currentLine] = removeLetter(program[currentLine], currentPos - 2)
                position["x"] = position["x"] - 1
            end
        end
        if events[2] == keys.enter and mode == "edit" then
            pChanged = true
            table.insert(program, currentLine + 1, program[currentLine]:sub(position["x"] + location["x"] - 1))
            program[currentLine] = program[currentLine]:sub(1, position["x"] + location["x"] - 2)
            program[currentLine + 1] = string.rep("$___", tabNum) .. program[currentLine + 1]
            position["y"] = position["y"] + 1
            position["x"] = 1 + tabNum * 4
        end
        if events[2] == keys.tab and mode == "edit" then
            lChanged = true
            if (position["x"] + location["x"] - 1) % 4 == 1 then
                program[currentLine] = addLetter("$___", program[currentLine], position["x"] + location["x"] - 1)
            else
                local num = (position["x"] + location["x"] - 1) % 4 + 1
                if num == 4 then num = 2 end
                program[currentLine] = addLetter(string.rep(" ", num), program[currentLine], position["x"] + location["x"] - 1)
            end
            position["x"] = position["x"] + 4
        end
    end
    if events[1] == "mouse_click" and events[2] == 1 and #program >= events[4] + location["y"] - 2 and events[4] > 1 then
        position["y"] = events[4] - 1
        position["x"] = events[3] - numlength
    elseif events[1] == "mouse_drag" and events[2] == 1 then
        clickEnd = {events[3] + location["x"] - 1, events[4] + location["y"] - 1}
    end
    if events[1] == "mouse_scroll" then
        pChanged = true
        location["y"] = location["y"] + events[2]
    end
end