// Copyright (c) 2025 shibedrill
// SPDX-License-Identifier: GPL-3.0-or-later

use lazy_static::lazy_static;
use x86_64::structures::idt::*;

use crate::format;

lazy_static! {
    pub static ref IDT: InterruptDescriptorTable = {
        let mut idt = InterruptDescriptorTable::new();
        // TODO: Re-implement this once the x86-interrupt ABI is fixed.
        //idt.double_fault.set_handler_fn(double_fault);
        idt.page_fault.set_handler_fn(page_fault);
        idt
    };
}

//extern "x86-interrupt" fn double_fault(info: InterruptStackFrame, _: u64) -> ! {
//    crate::interrupt::double_fault(&format!("{info:#?}"));
//}

extern "x86-interrupt" fn page_fault(info: InterruptStackFrame, errcode: PageFaultErrorCode) {
    if errcode.contains(PageFaultErrorCode::USER_MODE) {
        // Fault occurred in usermode. Non fatal.
        todo!()
    } else {
        // Fault occurred in kernel mode. This is possibly fatal.
        // This is recoverable if we simply hit an unavailable page,
        // but unrecoverable if we hit a nonexistent or invalid page.
        if errcode.contains(PageFaultErrorCode::PROTECTION_VIOLATION)
            | errcode.contains(PageFaultErrorCode::MALFORMED_TABLE)
        {
            let addr = unsafe {
                let a: usize;
                core::arch::asm! {"mov {}, cr2", out(reg) a};
                a
            };
            crate::interrupt::page_fault(addr, &format!("{info:#?}"))
        }
    }
}