//! Environment call handling routines
use {
    super::{mem::Memory, Vm},
    crate::{arch, ipc::buffer::IpcBuffer, kmain::IPC_BUFFERS},
    alloc::string::String,
    log::{debug, error, info, trace, warn},
};

pub fn handler(vm: &mut Vm) {
    let r1 = vm.registers[1].cast::<u64>();

    // debug!("Ecall number {:?}", r1);
    // trace!("Register dump: {:?}", vm.registers);

    match r1 {
        0 => {
            // TODO: explode computer
            // hello world ecall
            for x in 0u64..=255 {
                vm.registers[x as usize] = x.into();
            }
        }
        1 => {
            // Make buffer

            let bounded = match vm.registers[2].cast::<u64>() {
                0 => false,
                1 => true,
                _ => {
                    panic!("Bad");
                }
            };

            let length = vm.registers[3].cast::<u64>();

            let mut buffs = IPC_BUFFERS.lock();
            let abc;

            match bounded {
                false => {
                    abc = IpcBuffer::new(false, 0);
                }
                true => {
                    abc = IpcBuffer::new(true, length);
                }
            };
            let buff_id = arch::hardware_random_u64();
            buffs.insert(buff_id, abc);
            debug!("Buffer ID: {}", buff_id);
        }
        2 => {
            // Delete buffer
        }
        3 => {
            // Send a message to a buffer
            let r2 = vm.registers[2].cast::<u64>();
            let r3 = vm.registers[3].cast::<u64>();
            let r4 = vm.registers[4].cast::<u64>();

            let buffer_id = r2;
            let mem_addr = r3;
            let length = r4 as usize;
            trace!("IPC address: {:?}", mem_addr);
            use alloc::vec::Vec;

            match buffer_id {
                1 => {
                    log_msg_handler(vm, mem_addr, length);
                    // error!("Logging via IPC isn't quite ready")
                }
                buffer_id => {
                    info!("Message has been sent to {}", buffer_id)
                }
            }
        }
        // 4
        // 5
        _ => {
            log::error!("Syscall unknown {:?}", r1);
        }
    }
}

fn log_msg_handler(vm: &mut Vm, mem_addr: u64, length: usize) -> Result<(), LogError> {
    // let message_length = 8 + 8 + 8;
    let mut msg_vec = vec![];

    for x in 0..(length as isize) {
        let xyz = mem_addr as *const u8;
        let value = unsafe { xyz.offset(x).read() };
        // info!("{} - {:x?} - {}", value, value, value as char);
        msg_vec.push(value);
    }
    let log_level = msg_vec.pop().unwrap();
    let strr = String::from_utf8(msg_vec).unwrap();
    // info!("{}", strr);

    // use LogLevel::*;
    let ll = match log_level {
        48 => error!("{}", strr),
        49 => warn!("{}", strr),
        50 => info!("{}", strr),
        51 => debug!("{}", strr),
        52 => trace!("{}", strr),
        _ => return Err(LogError::InvalidLogFormat),
    };

    Ok(())
}

pub enum LogError {
    InvalidLogFormat,
}
use {alloc::vec, log::Record};