-- Function to draw the exit option
local function drawExitOption()
    term.setCursorPos(1, 1)
    term.setBackgroundColor(colors.black)
    term.setTextColor(colors.white)
    term.write("X")
    term.setBackgroundColor(colors.black)
end

-- Function to clear the screen with a black background
local function clearScreen()
    term.setBackgroundColor(colors.black)
    term.setTextColor(colors.white)
    term.clear()
    term.setCursorPos(1, 1)
end

local function getDiskID()
    local drive = peripheral.wrap("bottom")
    if drive and peripheral.getType("bottom") == "drive" then
        if drive.isDiskPresent() then
            local diskID = drive.getDiskID()
            return diskID
        else
            return nil, "No disk present in the drive."
        end
    else
        return nil, "No drive found at the bottom."
    end
end

local function listCards()
    clearScreen()
    drawExitOption()
    local cardDir = "/disk/Cards/"
    local files = fs.list(cardDir)
    if #files > 0 then
        print("Cards in /disk/Cards:")
        for _, file in ipairs(files) do
            print("- " .. file)
        end
    else
        print("No cards found in /disk/Cards.")
    end

    while true do
        local event, button, x, y = os.pullEvent("mouse_click")
        if x == 1 and y == 1 then
            return
        end
    end
end

local function linkCard()
    clearScreen()
    drawExitOption()
    print("Link Card:")
    print("1. Insert Card to Link")
    print("2. Enter Card ID")
    print("0. Back to Main Menu")

    while true do
        local event, button, x, y = os.pullEvent("mouse_click")
        if x == 1 and y == 1 then
            return
        end

        if event == "char" then
            local choice = tonumber(button)
            if choice == 1 then
                clearScreen()
                drawExitOption()
                print("Insert a disk to link or click cancel:")
                while true do
                    local diskID, errorMsg = getDiskID()
                    if diskID then
                        local cardFileName = "/disk/Cards/" .. diskID .. ".ID"
                        local file = fs.open(cardFileName, "w")
                        file.close()
                        print("Card linked successfully.")
                        sleep(2)
                        local drive = peripheral.wrap("bottom")
                        drive.ejectDisk()
                        return
                    elseif x == 1 and y == 1 then
                        return
                    else
                        print(errorMsg)
                        sleep(2)
                        return
                    end
                end
            elseif choice == 2 then
                clearScreen()
                drawExitOption()
                print("Enter the card ID:")
                local cardID = read()
                local cardFileName = "/disk/Cards/" .. cardID .. ".ID"
                local file = fs.open(cardFileName, "w")
                file.close()
                print("Card linked successfully.")
                sleep(2)
                return
            elseif choice == 0 then
                return
            else
                print("Invalid choice. Please enter 1, 2, or 0.")
            end
        end
    end
end

local function unlinkCard()
    clearScreen()
    drawExitOption()
    print("Unlink Card:")
    print("1. Insert Card to Unlink")
    print("2. Enter Card ID")
    print("0. Back to Main Menu")

    while true do
        local event, button, x, y = os.pullEvent("mouse_click")
        if x == 1 and y == 1 then
            return
        end

        if event == "char" then
            local choice = tonumber(button)
            if choice == 1 then
                clearScreen()
                drawExitOption()
                print("Insert a disk to unlink or click cancel:")
                while true do
                    local diskID, errorMsg = getDiskID()
                    if diskID then
                        local cardFileName = "/disk/Cards/" .. diskID .. ".ID"
                        if fs.exists(cardFileName) then
                            fs.delete(cardFileName)
                            print("Card unlinked successfully.")
                        else
                            print("No matching card found to unlink.")
                        end
                        sleep(2)
                        local drive = peripheral.wrap("bottom")
                        drive.ejectDisk()
                        return
                    elseif x == 1 and y == 1 then
                        return
                    else
                        print(errorMsg)
                        sleep(2)
                        return
                    end
                end
            elseif choice == 2 then
                clearScreen()
                drawExitOption()
                print("Enter the card ID:")
                local cardID = read()
                local cardFileName = "/disk/Cards/" .. cardID .. ".ID"
                if fs.exists(cardFileName) then
                    fs.delete(cardFileName)
                    print("Card unlinked successfully.")
                else
                    print("No matching card found to unlink.")
                end
                sleep(2)
                return
            elseif choice == 0 then
                return
            else
                print("Invalid choice. Please enter 1, 2, or 0.")
            end
        end
    end
end

local function mainMenu()
    clearScreen()
    drawExitOption()
    print("Main Menu:")
    print("1. List Cards")
    print("2. Link Card")
    print("3. Unlink Card")
    print("0. Exit")

    while true do
        local event, button, x, y = os.pullEvent("mouse_click")
        if x == 1 and y == 1 then
            os.reboot()
        end

        if event == "char" then
            local choice = tonumber(button)
            if choice == 1 then
                listCards()
                mainMenu()
            elseif choice == 2 then
                linkCard()
                mainMenu()
            elseif choice == 3 then
                unlinkCard()
                mainMenu()
            elseif choice == 0 then
                os.reboot()
            else
                print("Invalid choice. Please enter 1, 2, 3, or 0.")
            end
        end
    end
end

mainMenu()