Calculator

--[[ Variables ]]--
calc = ""
screenX, screenY = term.getSize()

if fs.exists("calcColor") == true then
 h = fs.open("calcColor", "r")
 borderColour = loadstring("return "..h.readLine())()
 h.close()
else
 h = fs.open("calcColor", "w")
 h.write("colors.white")
 h.close()
 borderColour = colors.white
end --if true then read file and set color to what was set before, if not then set to default of white


-- Tables
buttonsMain = {}
buttonsExtra = {}
buttonsColors = {}
input = {nil, nil, nil}
--[[ End of variables ]]--

--[[ Functions ]]--

function printVerticalLine(lineX, startingY, endingY)
        term.setBackgroundColor(borderColour)
        for lineY = startingY, endingY do
                term.setCursorPos(lineX, lineY)
                term.write(" ")
        end
end

function printHorizontalLine(yLine, startingX, endingX)
        term.setBackgroundColor(borderColour)
        term.setCursorPos(startingX, yLine)
        write(string.rep(" ", endingX - startingX + 1))
end

function drawMain()
        -- Left part (for numbers)
                printVerticalLine(2,2,18)
                --Left Border
                printVerticalLine(20,2,18)
                --Right Border
                printVerticalLine(8,6,18)
                --Left Seperator
                printVerticalLine(14,6,18)
                --Right Seperator
                printHorizontalLine(2,2,20)
                --Top
                printHorizontalLine(6,2, 20)
                --Upper Before Keys
                printHorizontalLine(18,2,20)
                --Bottom
                printHorizontalLine(10,2,20)
                --Upper Seperator
                printHorizontalLine(14,2,20)
                --Lower Seperator
                term.setBackgroundColor(colors.black)

        -- Middle area (F, H, c)
                printVerticalLine(23,6,18)
                --Left Border
                printVerticalLine(29,6,18)
                --Right Border
                printHorizontalLine(6,23,29)
                --Top
                printHorizontalLine(10,23,29)
                printHorizontalLine(14,23,29)
                printHorizontalLine(18,23,29)

        -- Right side (0, math synbols)
                printHorizontalLine(6,32,50)
                --Top
                printHorizontalLine(10,32,50)
                printHorizontalLine(14,32,50)
                printHorizontalLine(18,32,50)
                --Bottom
                printVerticalLine(32,6,18)
                --Left Border
                printVerticalLine(38,6,14)
                printVerticalLine(44,6,18)
                printVerticalLine(50,6,18)

        term.setBackgroundColor(colors.black)
end

function drawColorsTable()
        printVerticalLine(2,2,18)
        printVerticalLine(14,2,18)
        printVerticalLine(26,2,18)
        printVerticalLine(40,2,18)
        printVerticalLine(50,2,18)

        printHorizontalLine(2, 3, screenX-2)
        printHorizontalLine(6, 3, screenX-2)
        printHorizontalLine(10, 3, screenX-2)
        printHorizontalLine(14, 3, screenX-2)
        printHorizontalLine(18, 3, screenX-2)

        term.setBackgroundColor(colors.black)
end

function setTable(_table, name, xMin, xMax, yMin, yMax, customX, col)
        table.insert(_table, {
                numb = name,
                xmin = xMin,
                xmax = xMax,
                ymin = yMin,
                ymax = yMax,
                cX = customX or nil,
                txtCol = col or colours.white
        })
end

function fillTable()
        setTable(buttonsMain, "1", 3, 7, 15, 17)
        setTable(buttonsMain, "2", 9, 13, 15, 17)
        setTable(buttonsMain, "3", 15, 19, 15, 17)
        setTable(buttonsMain, "4", 3, 7, 11, 13)
        setTable(buttonsMain, "5", 9, 13, 11, 13)
        setTable(buttonsMain, "6", 15, 19, 11, 13)
        setTable(buttonsMain, "7", 3, 7, 7, 9)
        setTable(buttonsMain, "8", 9, 13, 7, 9)
        setTable(buttonsMain, "9", 15, 19, 7, 9)
        setTable(buttonsExtra, "1", 3, 7, 15, 17)
        setTable(buttonsExtra, "2", 9, 13, 15, 17)
        setTable(buttonsExtra, "3", 15, 19, 15, 17)
        setTable(buttonsExtra, "4", 3, 7, 11, 13)
        setTable(buttonsExtra, "5", 9, 13, 11, 13)
        setTable(buttonsExtra, "6", 15, 19, 11, 13)
        setTable(buttonsExtra, "7", 3, 7, 7, 9)
        setTable(buttonsExtra, "8", 9, 13, 7, 9)
        setTable(buttonsExtra, "9", 15, 19, 7, 9)
end

function fillFunctionsTable()
        setTable(buttonsMain, "C", 33,37,7,9)
        setTable(buttonsMain, ".", 39,43,7,9)
        setTable(buttonsMain, "/", 45,49,7,9)
        setTable(buttonsMain, "+", 33,37,11,13)
        setTable(buttonsMain, "-", 39,43,11,13)
        setTable(buttonsMain, "*", 45,49,11,13)
        setTable(buttonsMain, "0", 33,43,15,17)
        setTable(buttonsMain, "=", 45,49,15,17)
end

function fillExtraFunctions()
        setTable(buttonsExtra, "^", 33,37,7,9)
        setTable(buttonsExtra, "rt", 39,43,7,9)
        setTable(buttonsExtra, "/", 45,49,7,9)
        setTable(buttonsExtra, "+", 33,37,11,13)
        setTable(buttonsExtra, "-", 39,43,11,13)
        setTable(buttonsExtra, "*", 45,49,11,13)
        setTable(buttonsExtra, "0", 33,43,15,17)
        setTable(buttonsExtra, "=", 45,49,15,17)
end

function fillExtraButtonsTable()
        setTable(buttonsExtra, "F",24,28,7,9)
        setTable(buttonsExtra, "H",24,28,11,13)
        setTable(buttonsExtra, "c",24,28,15,17)
        setTable(buttonsMain, "F",24,28,7,9)
        setTable(buttonsMain, "H",24,28,11,13)
        setTable(buttonsMain, "c",24,28,15,17)
end

function fillColorOptions()
        setTable(buttonsColors,"White",3,13,3,5, 6, colours.white)
        setTable(buttonsColors,"Orange",3,13,7,9, 6, colours.orange)
        setTable(buttonsColors,"Magenta",3,13,11,13, 5, colours.magenta)
        setTable(buttonsColors,"Light Blue",3,13,15,17, 4, colours.lightBlue)
        setTable(buttonsColors,"Yellow",15,25,3,5, 17, colours.yellow)
        setTable(buttonsColors,"Lime",15,25,7,9, 18, colours.lime)
        setTable(buttonsColors,"Pink",15,25,11,13, 18, colours.pink)
        setTable(buttonsColors,"Gray",15,25,15,17, 18, colours.grey)
        setTable(buttonsColors,"Light Gray",27,37,3,5, 28, colours.lightGrey)
        setTable(buttonsColors,"Cyan",27,37,7,9, 32, colours.cyan)
        setTable(buttonsColors,"Purple",27,37,11,13, 30, colours.purple)
        setTable(buttonsColors,"Blue",27,37,15,17, 31, colours.blue)
        setTable(buttonsColors,"Brown",39,49,3,5, 43, colours.brown)
        setTable(buttonsColors,"Green",39,49,7,9, 43, colours.green)
        setTable(buttonsColors,"Red",39,49,11,13, 44, colours.red)
        setTable(buttonsColors,"Black",39,49,15,17, 43, colours.white)
end

function checkClick(tab, mx, my)
        for i, v in pairs(tab) do
                if mx >= v.xmin and mx <= v.xmax and my >= v.ymin and my <= v.ymax then
                        return true, v.numb
                end
        end
        return false, nil
end

function screen(tab)
        term.setBackgroundColour(colours.black)
        for i, data in pairs(tab) do
                local yspot = (data.ymin + data.ymax) / 2
                local xspot = data.cX or (data.xmin + data.xmax) / 2
                term.setCursorPos(xspot, yspot)
                term.setTextColour(data.txtCol)
                write(data.numb)
        end
end

function writeColor()
 h = fs.open("calcColor", "w")
 h.write(borderColour)
 h.close()
end

function redraw(t)
        term.setCursorPos(4, 4)
        write(string.rep(" ", 15))
        term.setCursorPos(4, 4)
        write(t or "")
end

function doSum()
        input[1] = tonumber(calc) or input[1]
        input[2] = numb
        redraw()
        calc = ""
        numb = ""
end

function enterPress()
        input[3] = tonumber(calc)
        if input[2] == "+" then
                Output = input[1] + input[3]
        elseif input[2] == "-" then
                Output = input[1] - input[3]
        elseif input[2] == "*" then
                Output = input[1] * input[3]
        elseif input[2] == "/" then
                Output = input[1] / input[3]
        elseif input[2] == "^" then
                Output = input[1] ^ input[3]
        elseif input[2] == "rt" then
                Output = math.sqrt(input[1])
        end
        redraw(Output)
        calc = tostring(Output)
        input[1] = Output
end

--[[ Functions for the middle section: Choosing a new border colour
          and to display help.
--]]
function chooseColour()
        term.setBackgroundColour(colours.black)
        term.setCursorPos(1, 1)
        term.clear()

        term.setBackgroundColour(colours.grey)
        write(string.rep(" ", screenX))

        term.setBackgroundColour(colours.red)
        term.setCursorPos(screenX, 1)
        write("X")

        while true do
                screen(buttonsColors)
                drawColorsTable()
                local e, but, x, y = os.pullEvent("mouse_click")
                if but == 1 then
                        if x == screenX and y == 1 then
                                term.clear()
                                screen(buttonsMain)
                                drawMain()
                                redraw(calc)
                                break
                        else
                                bValid, colChoice = checkClick(buttonsColors, x, y)
                                if bValid then
                                        if colChoice == "White" then
                                                borderColour = colours.white
                                                writeColor()
                                        elseif colChoice == "Orange" then
                                                borderColour = colours.orange
                                                writeColor()
                                        elseif colChoice == "Magenta" then
                                                borderColour = colours.magenta
                                                writeColor()
                                        elseif colChoice == "Light Blue" then
                                                borderColour = colours.lightBlue
                                                writeColor()
                                        elseif colChoice == "Yellow" then
                                                borderColour = colours.yellow
                                                writeColor()
                                        elseif colChoice == "Lime" then
                                                borderColour = colours.lime
                                                writeColor()
                                        elseif colChoice == "Pink" then
                                                borderColour = colours.pink
                                                writeColor()
                                        elseif colChoice == "Gray" then
                                                borderColour = colours.grey
                                                writeColor()
                                        elseif colChoice == "Light Gray" then
                                                borderColour = colours.lightGrey
                                                writeColor()
                                        elseif colChoice == "Cyan" then
                                                borderColour = colours.cyan
                                                writeColor()
                                        elseif colChoice == "Purple" then
                                                borderColour = colours.purple
                                                writeColor()
                                        elseif colChoice == "Blue" then
                                                borderColour = colours.blue
                                                writeColor()
                                        elseif colChoice == "Brown" then
                                                borderColour = colours.brown
                                                writeColor()
                                        elseif colChoice == "Green" then
                                                borderColour = colours.green
                                                writeColor()
                                        elseif colChoice == "Red" then
                                                borderColour = colours.red
                                                writeColor()
                                        elseif colChoice == "Black" then
                                                borderColour = colours.black
                                                writeColor()
                                        end
                                end
                        end
                end
        end
end

function displayHelp()
        term.setBackgroundColour(colours.white)
        term.setCursorPos(1, 1)
        term.clear()

        term.setBackgroundColour(colours.grey)
        write(string.rep(" ", screenX))

        term.setBackgroundColour(colours.red)
        term.setCursorPos(screenX, 1)
        write("X")

        term.setBackgroundColour(colours.white)
        term.setTextColour(colours.black)
        term.setCursorPos(1, 2)
        print("There will be help here once I decide to not be lazy and fill it out, for now check the forums!")

        repeat local _, but, x, y = os.pullEvent("mouse_click") until but == 1 and x == screenX and y == 1

        term.setBackgroundColour(colours.black)
        term.clear()

        drawMain()
        screen(buttonsMain)
end
--[[ End of functions ]]--

--[[ Main ]]--

-- Run the functions to fill the table with math functions
fillExtraFunctions()
fillTable()
fillFunctionsTable()
fillExtraButtonsTable()
fillColorOptions()

-- Run the functions to draw the tables
term.clear()
drawMain()

screen(buttonsMain)
state = "main"

while true do
        local e, but, x, y = os.pullEvent("mouse_click")
        if but == 1 then
                bValid, numb = checkClick(state == "main" and buttonsMain or state == "extra" and buttonsExtra, x, y)
                if bValid then
                        if numb == "+" or numb == "-" or numb == "*" or numb == "/" or
                        numb == "^" or numb == "rt" then
                                doSum()
                        elseif numb == "H" then
                                displayHelp()
                        elseif numb == "F" then
                                term.clear()
                                redraw(calc)
                                drawMain()
                                if state == "main" then
                                        state = "extra"
                                        screen(buttonsExtra)
                                elseif state == "extra" then
                                        state = "main"
                                        screen(buttonsMain)
                                end
                        elseif numb == "=" then
                        enterPress()
                        elseif numb == "c" then
                                chooseColour()
                        elseif numb == "C" then
                                for i = 1,3 do
                                        input[i] = nil
                                end
                                calc = ""
                                Output = ""
                                redraw()
                        elseif numb == "." then
                            calc = calc .. numb
                            term.setCursorPos(4,4)
                            if #calc < 14 then
                                write(calc)
                            else
                    write(calc:sub(#calc-14))
                end
                        elseif tonumber(numb) then -- if it is a number
                                calc = calc .. numb
                                term.setCursorPos(4, 4)
                                if #calc < 14 then
                                        write(calc)
                                else
                                        write(calc:sub(#calc-14))
                                end
                        end
                end
        end
end