button

--wrap the monitor as a peripheral
mon = peripheral.wrap("left")

mainBackground = colors.black
mainText = colors.white

--table that stores the buttons
buttons = {}

--define a new button
function newButton(lbl,txt,x,y,text,bg,border)--newButton(string,string,integer,integer,colors api,colors api,boolean)
    if type(lbl) ~= "string" then
        error("function newButton expects a string to label the button as its first argument")
    elseif type(txt) ~= "string" then
        error("function newButton expects a string to tell it what text to display as its second argument")
    elseif type(x) ~= "number" then
        error("function newButton expects an integer to determine the x coordinate of the button as its third argument")
    elseif type(y) ~= "number" then
        error("function newButton expects an integer to determine the y coordinate of the button as its forth argument")
    elseif type(text) ~= "number" then
        error("function newButton expects an integer or colors/colours API value to determine the color of the text as its fifth argument")
    elseif type(bg) ~= "number" then
        error("function newButton expects an integer or colors/colours API value to determine the background color of the button as its sixth argument")
    elseif type(border) ~= "boolean" then
        error("function newButton expects a boolean value to determine wether the button has a border as its seventh argument")
    elseif lbl == "all" then
        error("all cannot be used as the label for a button because it is used in other functions")
    elseif lbl == "timed out" then
        error("timed out cannot be used as the label for a button because it is used in other functions")
    end
    buttons[lbl] = {txt,x,y,false,lbl,text,bg,border}
end

--internal function to draw a button
local function draw(button)
    buttons[button][4] = true
    mon.setBackgroundColor(buttons[button][7])
    mon.setTextColor(buttons[button][6])
    mon.setCursorPos(buttons[button][2],buttons[button][3] + 1)
    mon.write(" "..buttons[button][1].." ")

    if buttons[button][8] then
        mon.setCursorPos(buttons[button][2],buttons[button][3])

        for i=1,string.len(buttons[button][1]) + 2 do
            mon.write(" ")
        end

        mon.setCursorPos(buttons[button][2],buttons[button][3] + 2)

        for i=1,string.len(buttons[button][1]) + 2 do
            mon.write(" ")
        end
    end
end

--internal function to erase a button
local function erase(button)
    buttons[button][4] = false
    mon.setBackgroundColor(mainBackground)
    mon.setTextColor(mainText)

    mon.setCursorPos(buttons[button][2],buttons[button][3] + 1)

    for i=1,string.len(buttons[button][1]) + 2 do
        mon.write(" ")
    end

    if buttons[button][8] then
        mon.setCursorPos(buttons[button][2],buttons[button][3] + 2)

        for i=1,string.len(buttons[button][1]) + 2 do
            mon.write(" ")
        end

        mon.setCursorPos(buttons[button][2],buttons[button][3])

        for i=1,string.len(buttons[button][1]) + 2 do
            mon.write(" ")
        end
    end
end

--draw either a button or all buttons
function drawButton(button)
    if type(button) ~= "string" then
        error("function drawButton expects the string label of the button you would like to draw or the string all to draw all buttons")
    end
    if button == "all" then
        for b in pairs(buttons) do
            draw(b)
        end
    else
        if buttons[button] ~= nil then
            draw(button)
        else
            error("button: "..button.." does not exist")
        end
    end
end

--erase either a button or all buttons
function eraseButton(button)
    if type(button) ~= "string" then
        error("function eraseButton expects the string label of the button you would like to erase or the string all to erase all buttons")
    end
    if button == "all" then
        for b in pairs(buttons) do
            erase(b)
        end
    else
        if buttons[button] ~= nil then
            erase(button)
        else
            error("button: "..button.." does not exist")
        end
    end
end

--clear the monitor and erase all buttons
function monDefault()
    mon.setBackgroundColor(mainBackground)
    mon.setTextColor(mainText)
    eraseButton("all")
    mon.clear()
    mon.setCursorPos(1,1)
end

function getClick(timeout)
    t = type(timeout)
    if t ~= "number" and t ~= "nil" then
        error("function getClick expects a number to determine the time before timing out or a blank/nil to represent no time limit")
    end
    if t == "number" then
        timeo = os.startTimer(timeout)
    end
    while true do
        local event,id,xPos,yPos = os.pullEvent()
        if event == "timer" and id == timeo then
            return "timed out"
        elseif event == "monitor_touch" then
            for button in pairs(buttons) do
                if buttons[button][8] and xPos >= buttons[button][2] and xPos <= buttons[button][2] + string.len(buttons[button][1]) + 1 and yPos >= buttons[button][3] and yPos <= buttons[button][3] + 2 and buttons[button][4] then
                    return button
                elseif (not buttons[button][8]) and xPos >= buttons[button][2] and xPos <= buttons[button][2] + string.len(buttons[button][1]) - 1 and yPos == buttons[button][3] and buttons[button][4] then
                    return button
                end
            end
        end
    end
end