#![no_std]
#![feature(abi_x86_interrupt)]
#![warn(
    clippy::correctness,
    clippy::nursery,
    clippy::unnecessary_cast,
    clippy::all,
    clippy::suspicious,
    clippy::perf,
    rustdoc::missing_errors_doc,
    rustdoc::missing_panics_doc
)]
#![deny(clippy::mod_module_files)]

extern crate alloc;

use core::arch::asm;
use limine::BaseRevision;

use libk::drivers::kalloc::allocator::init_heap;
use libk::prelude::*;

use x86_64::VirtAddr;

mod arch;

/// Sets the base revision to the latest revision supported by the crate.
/// See specification for further info.
/// Be sure to mark all limine requests with #[used], otherwise they may be removed by the compiler.
#[used]
// The .requests section allows limine to find the requests faster and more safely.
#[unsafe(link_section = ".requests")]
static BASE_REVISION: BaseRevision = BaseRevision::new();

#[panic_handler]
fn rust_panic(_info: &core::panic::PanicInfo) -> ! {
    println!("Kernel panic: {}", _info);
    serial_println!("Kernel panic: {}", _info);
    hcf();
}

pub fn hcf() -> ! {
    loop {
        unsafe {
            #[cfg(target_arch = "x86_64")]
            asm!("hlt");
            #[cfg(any(target_arch = "aarch64", target_arch = "riscv64"))]
            asm!("wfi");
            #[cfg(target_arch = "loongarch64")]
            asm!("idle 0");
        }
    }
}

pub fn boot() -> Result<(), &'static str> {
    if !BASE_REVISION.is_supported() {
        return Err("base revision not supported");
    }

    use arch::x86_64::{gdt, interrupts, memmap, memory};

    let memory_map = memmap::get_memory_map();

    print_log!("    Initialising Serial... ");
    libk::drivers::io::serial::init()?;
    println_log!("[Success]");

    print_log!("    Setting Up Global Descriptor Table... ");
    gdt::init();
    println_log!("[Success]");

    print_log!("    Setting Up Interrupt Descriptor Table... ");
    interrupts::init_idt();
    println_log!("[Success]");

    print_log!("    Setting Up Page Table... ");
    let mut frame_allocator = unsafe { memory::FoundryOSFrameAllocator::init(memory_map) };
    println_log!("[Success]");

    print_log!("    Initialising Memory Subsystem... ");
    let physical_memory_offset = VirtAddr::new(*memmap::PHYSICAL_MEMORY_OFFSET);
    let mut l4_table = unsafe { memory::init(physical_memory_offset) };
    println_log!("[Success]");

    print_log!("    Initialising Heap... ");
    if init_heap(&mut l4_table, &mut frame_allocator).is_err() {
        return Err("Failed to initialise heap: error");
    }
    println_log!("[Success]");

    print_log!("    Enabling Interrupts... ");
    x86_64::instructions::interrupts::enable();
    println_log!("[Success]");

    Ok(())
}