gui

local function Button(
                                width,
                                height,
                                label,
                                backgroundColorNormal,
                                backgroundColorPressed,
                                textColorNormal,
                                textColorPressed,
                                hasBorder,
                                borderColorNormal,
                                borderColorPressed,
                                startColumn,
                                startRow,
                                isPressed,
                                defaultBackgroundColor,
                                defaultTextColor
                            )
    local button = {}
    button.height=height or 1
    button.width=width or 1
    button.label=label or ""
    button.backgroundColorNormal=backgroundColorNormal or colors.black
    button.backgroundColorPressed=backgroundColorPressed or colors.white
    button.textColorNormal=textColorNormal or colors.white
    button.textColorPressed=textColorPressed or colors.black
    button.hasBorder = hasBorder or false
    button.borderColorNormal = borderColorNormal or backGroundColorNormal
    button.borderColorPressed = borderColorPressed or backGroundColorPressed
    button.defaultBackgroundColor = defaultBackgroundColor or colors.black
    button.defaultTextColor = defaultTextColor or colors.white
    button.startColumn = startColumn or 1
    button.startRow = startRow or 1
    button.isPressed=isPressed or false
    function button.press()
        button.isPressed = not button.isPressed
    end

    function button.draw(display,isPressed,startColumn,startRow)

        button.startColumn = startColumn or button.startColumn
        button.startRow = startRow or button.startRow
        display = display or term
        if isPressed == false or isPressed then
            button.isPressed = isPressed
        else isPressed = button.isPressed
        end
        local width = button.width
        local height = button.height
        startRow = button.startRow
        startColumn = button.startColumn

        local label = button.label
        local localPad = 2

        -- set border params and draw border if hasBorder
        if button.hasBorder == true then
            -- button must be at least 3x3, if not, make it so
            if width < 3 then
                width = 3
            end
            if height < 3 then
                height = 3
            end

            -- set border colors
            if not isPressed then
                if not display.isColor() then
                    display.setBackgroundColor(colors.white)
                else
                    display.setBackgroundColor(button.borderColorNormal)
                end
            else
                if not display.isColor() then
                    display.setBackgroundColor(colors.white)
                else
                    display.setBackgroundColor(button.borderColorPressed)
                end
            end

            -- draw button border (inset)
            display.setCursorPos(startColumn,startRow)
            display.write(string.rep(" ",width))
            for row = 2,height-1 do
                display.setCursorPos(startColumn,button.startRow+row -1)
                display.write(" ")
                display.setCursorPos(startColumn+width -1 ,startRow + row-1)
                display.write(" ")
            end
            display.setCursorPos(startColumn,startRow+height-1)
            display.write(string.rep(" ",width))

            -- reset startColumn,startRow,width,column to inset button and label
            startColumn=startColumn+1
            startRow = startRow +1
            width = width - 2
            height = height - 2
        end

        --set button background and text colors
        if not isPressed then
            if not display.isColor() then
                display.setBackgroundColor(colors.black)
                display.setTextColor(colors.white)
            else
                display.setBackgroundColor(button.backgroundColorNormal)
                display.setTextColor(button.textColorNormal)
            end
        else
            if not display.isColor() then
                display.setBackgroundColor(colors.white)
                display.setTextColor(colors.black)
            else
                display.setBackgroundColor(button.backgroundColorPressed)
                display.setTextColor(button.textColorPressed)
            end
        end

        -- draw button background (will be inside border if there is one)
        for row = 1,height do
            --print(tostring(startColumn)..","..tostring(startRow-row))
            display.setCursorPos(startColumn,startRow + row -1)
            display.write(string.rep(" ",width))
        end

        -- prepare label, truncate label if necessary

        if width < 3 then
            localPad = 0
        end
        if #label > width - localPad then
            label = label:sub(1,width - localPad)
        end

        -- draw label
        display.setCursorPos(startColumn + math.floor((width - #label)/2),startRow + math.floor((height-1)/2))
        display.write(label)
        display.setBackgroundColor(button.defaultBackgroundColor)
        display.setTextColor(button.defaultTextColor)
    end

    return button
end


local attachedMonitor = peripheral.wrap("top")
attachedMonitor.clear()
attachedMonitor.setTextScale(1)
local HQ_button = Button(
                            10,3,  --width,height
                            "HQ", --label
                            colors.blue,colors.red, -- background colors
                            colors.white,colors.yellow, -- text colors
                            true,colors.lightBlue, colors.pink, -- hasBorder, border colors
                            10,10, -- starting location
                            false, -- isPressed?
                            colors.black,colors.white -- default colors
                            )
rednet.open("back")
HQ_button.draw(attachedMonitor)
while true do

  event = {os.pullEvent()}
  trainPresent = rs.getInput("left")

  if event[1] == "monitor_touch" and not trainPresent then
    attachedMonitor.clear()
    attachedMonitor.setCursorPos(1,1)
    attachedMonitor.write("> Requesting train.")
    HQ_button.draw(attachedMonitor,true)
    rednet.broadcast("HQ", "dispatch_request")
    id, message = rednet.receive("dispatch_confirmation",5)
    if not (message == nil) then
      attachedMonitor.clear()
      attachedMonitor.setCursorPos(1,1)
      attachedMonitor.write("> Inbound from: "..message)
    else
      attachedMonitor.clear()
      attachedMonitor.setCursorPos(1,1)
      attachedMonitor.write("> No response from depot.")
    end
    HQ_button.draw(attachedMonitor, false)
  elseif event[1] == "rednet_message" and event[4] == "dispatch_request" and trainPresent then
    rednet.broadcast("Desert Station", "dispatch_confirmation")
    rs.setOutput("bottom", true)
    sleep(5)
    rs.setOutput("bottom", true)
  end

end
attachedMonitor.setCursorPos(1,9)
print("Done.")