#![allow(clippy::empty_loop)]

pub extern crate externc_libm as libm;

use {
    crate::{
        arch::{drivers::graphics::GraphicsBuffer, init, sloop},
        driver_traits::graphics::Graphics,
        experiments::systeminfo::{KERNEL_VERSION, RELEASE_TYPE},
        keyboard::DecodedKey,
        relib::math::rand::RAND_HANDLE,
        scheduler::{test_fn, Thread, ThreadList},
    },
    alloc::{boxed::Box, rc::Rc, vec, vec::Vec},
    lazy_static::lazy_static,
};

#[no_mangle]
#[allow(unconditional_recursion)]
pub extern "C" fn stack_overflow() -> u8 {
    stack_overflow();
    // meme number
    69 // NOTE: Any specific reason for this number asside from memes?
}

lazy_static! {
    pub static ref KEY_BUFFER: [DecodedKey; 256] = [DecodedKey::RawKey(123); 256];
    pub static ref KEY_BUFFER_POINTER: u8 = 0;
    pub static ref THREAD_LIST: spin::Mutex<ThreadList> = spin::Mutex::new(vec![]);
    pub static ref TICK: spin::Mutex<u64> = spin::Mutex::new(0);
}

use crate::log::{self, Log};
#[no_mangle]
pub fn kernel_main() -> ! {
    init::init();
    let mut a_thread = Thread::new();

    a_thread.new_task(test_fn);
    a_thread.new_task(test_fn);

    THREAD_LIST.lock().push(a_thread);

    GraphicsBuffer::draw();
    GraphicsBuffer::hide_cursor();
    GraphicsBuffer::show_cursor();
    if false {
        test_alloc();
    }
    // crate::wasm::evaluate();

    println!("{} v{}", RELEASE_TYPE, KERNEL_VERSION);
    info!("{} v{}", RELEASE_TYPE, KERNEL_VERSION);
    {
        use crate::experiments::mail::MailBoxes;
        let mut x = MailBoxes::new();
        x.set_flag(1);
        x.set_flag(2);
        // x.dump_flags();
    }

    // stack_overflow();
    // crate::arch::shutdown();
    sloop()
}

/// called by arch specific timers to tick up all kernel related functions
pub fn tick() {
    let mut data = TICK.lock();
    *data += 1;
    RAND_HANDLE.lock().seed_entropy_timer(*data);
}

pub fn key_entropy(key: u8) {
    RAND_HANDLE.lock().seed_entropy_keyboard(key);
}

fn test_alloc() {
    let x: Vec<u8> = vec![1];
    println!("{:?}", x);

    let heap_value = Box::new(41);
    println!("heap_value at {:p}", heap_value);

    // create a dynamically sized vector
    let mut vec = Vec::new();
    for i in 0..500 {
        vec.push(i);
    }
    println!("vec at {:p}", vec.as_slice());

    // create a reference counted vector -> will be freed when count reaches 0
    let reference_counted = Rc::new(vec![1, 2, 3]);
    let cloned_reference = reference_counted.clone();
    println!(
        "current reference count is {}",
        Rc::strong_count(&cloned_reference)
    );
    core::mem::drop(reference_counted);
    println!(
        "reference count is {} now",
        Rc::strong_count(&cloned_reference)
    );
}