os.pullEvent = os.pullEventRaw

if not multishell then
    term.clear()
    term.setCursorPos(1, 1)
    print("Doggy OS Install Error: Unsupported System")
    read()
    disk.eject("back")
    disk.eject("bottom")
    disk.eject("left")
    disk.eject("right")
    disk.eject("top")
    disk.eject("front")
    os.reboot()
    return
else
    -- Center the text within the given width
    function centerText(text, width)
        local padding = math.max(0, math.floor((width - #text) / 2))
        return string.rep(" ", padding) .. text
    end

    -- Draw a border with specified width and height
    function drawBorder(width, height)
        term.setCursorPos(1, 1)
        term.write("+" .. string.rep("-", width - 2) .. "+")
        for i = 2, height - 1 do
            term.setCursorPos(1, i)
            term.write("|")
            term.setCursorPos(width, i)
            term.write("|")
        end
        term.setCursorPos(1, height)
        term.write("+" .. string.rep("-", width - 2) .. "+")
    end

    -- Function to draw a graphical button
    function drawButton(x, y, width, height, label, color)
        term.setCursorPos(x, y)
        term.setBackgroundColor(color)
        term.setTextColor(colors.black)
        term.write(string.rep(" ", width))  -- Draw button
        term.setCursorPos(x + math.floor((width - #label) / 2), y + math.floor(height / 2))
        term.write(label)
        term.setBackgroundColor(colors.black)  -- Reset background
    end

    -- Draw the installation screen with GUI elements
    function drawGUI(width, height)
        -- Clear the screen and draw the border
        term.clear()
        drawBorder(width, height)

        local y = 4
        term.setCursorPos(3, y)
        term.setTextColor(colors.white)
        print(centerText("Doggy OS Installation", width - 4))

        y = y + 2
        term.setCursorPos(3, y)
        print(centerText("OS Version: Doggy OS 13.0", width - 4))

        y = y + 1
        term.setCursorPos(3, y)
        print(centerText("UEFI: N3K0 Config", width - 4))

        y = y + 1
        term.setCursorPos(3, y)
        print(centerText("Bootloader: VA11-ILLA 13.0", width - 4))

        y = y + 3
        term.setCursorPos(3, y)
        print(centerText("Confirm Installation", width - 4))

        -- Create two graphical buttons: Install (Y) and Cancel (N)
        drawButton(3, y + 2, width - 6, 3, "Install OS (Y)", colors.green)
        drawButton(3, y + 6, width - 6, 3, "Cancel Installation (N)", colors.red)

        -- Footer line
        y = y + 9
        term.setCursorPos(3, y)
        print(centerText("================================", width - 4))
    end

    -- Function to detect if a button is clicked
    function buttonClicked(x, y, width, height, mx, my)
        return mx >= x and mx <= x + width - 1 and my >= y and my <= y + height - 1
    end

    -- Main function to handle the installation process
    function main()
        term.clear()
        local w, h = term.getSize()
        local contentHeight = 16
        local borderPadding = 2  -- Padding between border and content

        -- Adjust height for border padding
        local heightWithBorders = contentHeight + borderPadding * 2

        -- Make sure the height fits within the screen
        local displayHeight = math.min(h, heightWithBorders)
        drawGUI(w, displayHeight)

        -- Track mouse clicks
        while true do
            local event, button, mx, my = os.pullEventRaw()

            -- Check for mouse clicks on the "Install OS" or "Cancel Installation" buttons
            if event == "mouse_click" then
                if button == 1 then  -- Left-click
                    if buttonClicked(3, 9, w - 6, 3, mx, my) then
                        runProgram()
                    elseif buttonClicked(3, 13, w - 6, 3, mx, my) then
                        term.clear()
                        term.setCursorPos(1, 1)
                        drawBorder(w, 7)
                        term.setCursorPos(3, 2)
                        print(centerText("Installation Cancelled", w - 4))
                        term.setCursorPos(3, 3)
                        print(centerText("Shutting Down...", w - 4))
                        sleep(4)
                        os.shutdown()
                    end
                end
            end
        end
    end

    function runProgram()
        -- Run the installation program
        shell.run("/disk/install")  -- Replace with your actual program name

        term.clear()
        term.setCursorPos(1, 1)
        print("Doggy OS Install Error")
        print("====================================")
        print("Unable to load installation program")
        print("Press enter to retry")
        read()
        os.reboot()
    end

    main()
end