#![no_std]
#![feature(never_type)]
#![feature(c_size_t)] // for ffi, tracking issue [88345]
//TODO os errors in API calls

mod dh;
pub mod fsrc;
mod panic;

use core::fmt::Write;
use core::time::Duration;

use fsrc::*;
use osal::{
    queue::{MessageQueue, MessageQueueSender},
    sync::{Mutex, MutexClone, StaticInit, StaticReadOnceLock},
    thread,
};

use crate::{
    dh::EchoHandler,
    fsrc::{
        dh::debug::DeviceHandlerDebugger,
        osal::io::HardwareInterface,
    },
};

static THREAD_INIT: StaticReadOnceLock<
    thread::StaticThread<{ thread::Sizes::MINIMAL_STACK_SIZE + 2024 }>,
> = StaticReadOnceLock::new(thread::StaticThread::new("Init", u32::MAX));

#[no_mangle]
extern "C" fn rust_main() {
    // we are already in a task (init task started by C), so we can use all APIs safely,
    // but start a new init task anyway to be able to control that task's stack here
    sifln!("Rust startup 🚀");
    THREAD_INIT.take_no_init().unwrap().spawn(init_task);
    // delete self, init task will take over
    thread::current().delete();
}

struct Test {
    a: u8,
    block: Duration,
    mutex: Mutex<u8>,
}

struct Test2 {
    a: u8,
    period: Duration,
}

impl Test {
    fn run(&mut self) {
        sifln!("Test: {} taking mutex", self.a);
        let mut guard = self.mutex.lock();
        let data: u8 = *guard;
        sifln!("Test: {} took mutex, was {}", self.a, data);
        osal::thread::current().delay(self.block);
        *guard = self.a;
        sifln!("Test: {} giving mutex, is now {}", self.a, *guard);
        drop(guard);
        sifln!("Test: {} gave mutex", self.a);
    }
}

impl Test2 {
    pub fn run(&mut self, mutex: MutexClone<u8>, block: Duration) -> ! {
        sifln!(
            "Stack watermark {}",
            osal::thread::current().stack_watermark()
        );
        loop {
            sifln!("Test2: {} taking mutex", self.a);
            let mut guard = mutex.lock();
            let data: u8 = *guard;
            sifln!("{} took mutex, was {}", self.a, data);
            sifln!(
                "Test2: Stack watermark {}",
                osal::thread::current().stack_watermark()
            );
            osal::thread::current().delay(block);
            *guard = self.a;
            sifln!("Test2: {} giving mutex, is now {}", self.a, *guard);
            drop(guard);
            sifln!("Test2: {} gave mutex", self.a);
            osal::thread::current().delay(self.period);
        }
    }
}

impl StaticInit for Test {
    fn static_init(&'static mut self) {
        self.mutex.static_init();
    }
}

impl StaticInit for Test2 {
    fn static_init(&'static mut self) {}
}

static TEST1: StaticReadOnceLock<Test> = StaticReadOnceLock::new(Test {
    a: 1,
    block: Duration::from_millis(1000),
    mutex: Mutex::new(13),
});
static THREAD_1: StaticReadOnceLock<
    thread::StaticThreadPeriodic<{ thread::Sizes::MINIMAL_STACK_SIZE + 512 }>,
> = StaticReadOnceLock::new(thread::StaticThreadPeriodic::new(
    "Thread 1",
    2,
    Duration::from_millis(1000),
));

static TEST2: StaticReadOnceLock<Test2> = StaticReadOnceLock::new(Test2 {
    a: 2,
    period: Duration::from_millis(5000),
});

static THREAD_2: StaticReadOnceLock<
    thread::StaticThread<{ thread::Sizes::MINIMAL_STACK_SIZE + 512 }>,
> = StaticReadOnceLock::new(thread::StaticThread::new("Thread 2", 2));

#[derive(Copy, Clone, Default)]
pub enum Message {
    OK,
    #[default]
    NONE,
    DATA(u8),
}

struct Receiver {
    queue: MessageQueue<Message, 100>,
}

impl Receiver {
    fn run(&self) {
        let message = self.queue.receive();
        let message = if let Ok(message) = message {
            message
        } else {
            sifln!("receiver: got nothing");
            return;
        };

        match message {
            Message::OK => {
                sifln!("receiver: ok");
            }
            Message::NONE => {
                sifln!("receiver: NONE");
            }
            Message::DATA(data) => {
                sifln!("receiver: {}", data);
            }
        }
    }
}

impl StaticInit for Receiver {
    fn static_init(&'static mut self) {
        self.queue.static_init();
    }
}

struct Sender {
    count: u8,
}

impl Sender {
    fn run(&mut self, queue: MessageQueueSender<Message>) {
        let _ = queue.send(Message::DATA(self.count));
        self.count += 1;
    }
}

static SENDER: StaticReadOnceLock<Sender> = StaticReadOnceLock::new(Sender { count: 0 });
static RECEIVER: StaticReadOnceLock<Receiver> = StaticReadOnceLock::new(Receiver {
    queue: MessageQueue::new(),
});
static THREAD_3: StaticReadOnceLock<
    thread::StaticThreadPeriodic<{ thread::Sizes::MINIMAL_STACK_SIZE + 512 }>,
> = StaticReadOnceLock::new(thread::StaticThreadPeriodic::new(
    "Thread 3",
    2,
    Duration::from_millis(200),
));

fn init_task() -> ! {
    sifln!("Mission enter");

    let commands = [dh::Command(0), dh::Command(1), dh::Command(2)];
    let mut debugger = DeviceHandlerDebugger::new(
        EchoHandler { buffer: [0; 10] },
        HardwareInterface::new("debug/uart🚀").unwrap(),
        &commands,
        &[],
        Duration::from_millis(500),
        0.5,
    );

    debugger.run().unwrap();

    let test1 = TEST1.take().unwrap();
    let test2 = TEST2.take().unwrap();
    let receiver = RECEIVER.take().unwrap();
    let sender_handle = receiver.queue.sender();
    let clone = sender_handle.clone();
    let sender = SENDER.take_no_init().unwrap();

    let mutex_copy = test1.mutex.clone();
    let a = Duration::from_millis(10);

    THREAD_2.take_no_init().unwrap().spawn(move || {
        test2.run(mutex_copy, a);
    });

    THREAD_1.take_no_init().unwrap().spawn(move || {
        test1.run();
        sender.run(clone);
    });

    THREAD_3.take_no_init().unwrap().spawn(move || {
        receiver.run();
    });
    
    sifln!("=====================Mission delete");
    osal::thread::current().delete();
}