Monitor Tutorial P2ex4

-- Set up variables
local attachedMonitor = peripheral.wrap("top")
local defaultBackgroundColor =colors.black
local defaultTextColor=colors.white

local backgroundColorNormal = colors.blue
local backgroundColorPressed = colors.red

local textColorNormal = colors.white
local textColorPressed = colors.yellow

local width=10
local height = 3

local label="Button"

local startColumn=3
local startRow=3

local labelPad = 2

-- our draw function

local function draw(isPressed)
    if isPressed == false or isPressed then
        isPressed = isPressed
    else
        isPressed = false
    end

    -- set the button/label colors
    if not isPressed then
        if not attachedMonitor.isColor() then
            attachedMonitor.setBackgroundColor(colors.black)
            attachedMonitor.setTextColor(colors.white)
        else
            attachedMonitor.setBackgroundColor(backgroundColorNormal)
            attachedMonitor.setTextColor(textColorNormal)
        end
    else
        if not attachedMonitor.isColor() then
            attachedMonitor.setBackgroundColor(colors.white)
            attachedMonitor.setTextColor(colors.black)
        else
            attachedMonitor.setBackgroundColor(backgroundColorPressed)
            attachedMonitor.setTextColor(textColorPressed)
        end
    end

    -- Display the button Background
    for row = startRow,startRow+height-1 do
        attachedMonitor.setCursorPos(startColumn,row)
        attachedMonitor.write(string.rep(" ",width))
    end

    -- prepare label, truncate label if necessary
    if width  < 3 then
        labelPad = 0
    end
    if #label > width - labelPad then
        label = label:sub(1,width - labelPad)
    end

    --Display the label (auto centered)
    attachedMonitor.setCursorPos(startColumn + math.floor((width - #label)/2),startRow + math.floor((height-1)/2))
    attachedMonitor.write(label)

    -- reset to original text/background colors
    if not attachedMonitor.isColor() then
        attachedMonitor.setBackgroundColor(colors.black)
        attachedMonitor.setTextColor(colors.white)
    else
        attachedMonitor.setBackgroundColor(defaultBackgroundColor)
        attachedMonitor.setTextColor(defaultTextColor)
    end
end

-- Set up Monitor
if not attachedMonitor.isColor() then
    attachedMonitor.setBackgroundColor(colors.black)
    attachedMonitor.setTextColor(colors.white)
else
    attachedMonitor.setBackgroundColor(defaultBackgroundColor)
    attachedMonitor.setTextColor(defaultTextColor)
end
--attachedMonitor.setTextScale(.5)
attachedMonitor.clear()

draw(false)
sleep(3)
draw(true)

attachedMonitor.setCursorPos(1,8)
attachedMonitor.write("Done.")