use std::{
    sync::{
        atomic::{AtomicBool, Ordering::SeqCst},
        Mutex,
    },
    thread,
};

use gtk::{prelude::*, PolicyType, TextView};
use gtk::{Application, ApplicationWindow};

use gtk::{Button, Entry, Orientation, ScrolledWindow};

use glib;

mod port;
use port::*;

static CONNECTED: AtomicBool = AtomicBool::new(false);
static PORT: Mutex<Option<Port>> = Mutex::new(None);

fn main() {
    let app = Application::builder()
        .application_id("org.example.HelloWorld")
        .build();

    app.connect_activate(move |app| {
        // We create the main window.
        let window = ApplicationWindow::builder()
            .application(app)
            .default_width(320)
            .default_height(200)
            .title("Hello, World!")
            .build();

        let master_box = gtk::Box::new(Orientation::Vertical, 5);
        let top_bar_box = gtk::Box::new(Orientation::Horizontal, 5);
        let pid = Entry::builder().text("0x27dd").editable(true).build();
        let vid = Entry::builder().text("0x16c0").editable(true).build();
        let connect_button = Button::with_label("Connect");
        let reset_button = Button::with_label("Reset");
        let serial_info = TextView::new();
        let scrolled_window = ScrolledWindow::builder()
            .vscrollbar_policy(PolicyType::Automatic)
            .child(&serial_info)
            .build();

        top_bar_box.pack_end(&connect_button, true, true, 3);
        top_bar_box.pack_end(&reset_button, true, true, 3);
        top_bar_box.pack_end(&vid, true, true, 3);
        top_bar_box.pack_end(&pid, true, true, 3);

        master_box.pack_end(&scrolled_window, true, true, 3);
        master_box.pack_end(&top_bar_box, false, true, 3);

        let (tx, rx) = glib::MainContext::channel(glib::PRIORITY_DEFAULT);

        std::thread::spawn(move || {
            // loop forever
            loop {
                let mut port_lock = PORT.lock().unwrap();

                if let Some(port) = &mut *port_lock {
                    // handle incoming message
                    match port.read().unwrap() {
                        SerialReadResult::Message(msg) => {
                            if !msg.is_empty() {
                                tx.send(msg).unwrap();
                            }
                        }
                        SerialReadResult::UtfConversion(err) => println!("{:?}", err),
                        SerialReadResult::Timeout => (),
                    }
                }

                drop(port_lock);

                thread::sleep(Duration::from_millis(10));
            }
        });

        connect_button.connect_clicked(move |_| {
            if !CONNECTED.load(SeqCst) {
                let usb_id = UsbId {
                    vendor_id: u16::from_str_radix(
                        vid.buffer().text().trim_start_matches("0x"),
                        16,
                    )
                    .unwrap(),
                    product_id: u16::from_str_radix(
                        pid.buffer().text().trim_start_matches("0x"),
                        16,
                    )
                    .unwrap(),
                };

                let serialport_settings = SerialPortSettings {
                    baud_rate: 9600,
                    data_bits: DataBits::Eight,
                    parity: Parity::None,
                    stop_bits: StopBits::One,
                    flow_control: FlowControl::None,
                    timeout: Duration::from_millis(2500),
                };

                if let Ok(port) = Port::open(usb_id, serialport_settings) {
                    CONNECTED.store(true, SeqCst);

                    *PORT.lock().unwrap() = Some(port);
                }
            }
        });

        reset_button.connect_clicked(move |_| {
            if CONNECTED.load(SeqCst) {
                CONNECTED.store(false, SeqCst);

                let mut port_lock = PORT.lock().unwrap();

                if let Some(port) = &mut *port_lock {
                    port.write("reset").unwrap();
                }

                *port_lock = None;
            }
        });

        let buffer = serial_info.buffer().unwrap();

        rx.attach(None, move |message| {
            if !message.is_empty() {
                buffer.insert(&mut buffer.end_iter(), &format!("{}\n", message));
                serial_info.scroll_to_iter(&mut buffer.end_iter(), 0.0, true, 0.0, 0.0);
            }

            glib::Continue(true)
        });

        window.add(&master_box);

        // Don't forget to make all widgets visible.
        window.show_all();
    });

    app.run();
}