#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]

use defmt::*;
use embassy_executor::Spawner;
use embassy_futures::join::join;
use embassy_stm32::rcc::*;
use embassy_stm32::usb::Driver;
use embassy_stm32::{interrupt, Config};
use embassy_time::{Duration, Timer};
use embassy_usb::class::hid::{HidWriter, ReportId, RequestHandler, State};
use embassy_usb::control::OutResponse;
use embassy_usb::Builder;
use usbd_hid::descriptor::{MouseReport, SerializedDescriptor};
use {defmt_rtt as _, panic_probe as _};

#[embassy_executor::main]
async fn main(_spawner: Spawner) {
    let mut config = Config::default();
    config.rcc.mux = ClockSrc::PLL(PLLSource::HSI16, PLLClkDiv::Div2, PLLSrcDiv::Div1, PLLMul::Mul10, None);
    config.rcc.hsi48 = true;
    let p = embassy_stm32::init(config);

    // Create the driver, from the HAL.
    let irq = interrupt::take!(USB_FS);
    let driver = Driver::new(p.USB, irq, p.PA12, p.PA11);

    // Create embassy-usb Config
    let mut config = embassy_usb::Config::new(0xc0de, 0xcafe);
    config.manufacturer = Some("Embassy");
    config.product = Some("HID mouse example");
    config.serial_number = Some("12345678");
    config.max_power = 100;
    config.max_packet_size_0 = 64;

    // Create embassy-usb DeviceBuilder using the driver and config.
    // It needs some buffers for building the descriptors.
    let mut device_descriptor = [0; 256];
    let mut config_descriptor = [0; 256];
    let mut bos_descriptor = [0; 256];
    let mut control_buf = [0; 64];
    let request_handler = MyRequestHandler {};

    let mut state = State::new();

    let mut builder = Builder::new(
        driver,
        config,
        &mut device_descriptor,
        &mut config_descriptor,
        &mut bos_descriptor,
        &mut control_buf,
        None,
    );

    // Create classes on the builder.
    let config = embassy_usb::class::hid::Config {
        report_descriptor: MouseReport::desc(),
        request_handler: Some(&request_handler),
        poll_ms: 60,
        max_packet_size: 8,
    };

    let mut writer = HidWriter::<_, 5>::new(&mut builder, &mut state, config);

    // Build the builder.
    let mut usb = builder.build();

    // Run the USB device.
    let usb_fut = usb.run();

    // Do stuff with the class!
    let hid_fut = async {
        let mut y: i8 = 5;
        loop {
            Timer::after(Duration::from_millis(500)).await;

            y = -y;
            let report = MouseReport {
                buttons: 0,
                x: 0,
                y,
                wheel: 0,
                pan: 0,
            };
            match writer.write_serialize(&report).await {
                Ok(()) => {}
                Err(e) => warn!("Failed to send report: {:?}", e),
            }
        }
    };

    // Run everything concurrently.
    // If we had made everything `'static` above instead, we could do this using separate tasks instead.
    join(usb_fut, hid_fut).await;
}

struct MyRequestHandler {}

impl RequestHandler for MyRequestHandler {
    fn get_report(&self, id: ReportId, _buf: &mut [u8]) -> Option<usize> {
        info!("Get report for {:?}", id);
        None
    }

    fn set_report(&self, id: ReportId, data: &[u8]) -> OutResponse {
        info!("Set report for {:?}: {=[u8]}", id, data);
        OutResponse::Accepted
    }

    fn set_idle_ms(&self, id: Option<ReportId>, dur: u32) {
        info!("Set idle rate for {:?} to {:?}", id, dur);
    }

    fn get_idle_ms(&self, id: Option<ReportId>) -> Option<u32> {
        info!("Get idle rate for {:?}", id);
        None
    }
}