use std::os::mikros::{ipc, syscalls, Errno};

use parking_lot::Mutex;
use uart::{
    Baud, Data, DataBits, FifoSize, InterruptEnable, LineControl, LineStatus, ModemControl,
    ParityMode, Uart, UartAddress,
};

struct DevServ;

impl dev_driver_rpc::Server for DevServ {
    fn open(&self, _path: &std::path::Path) -> Result<u64, Errno> {
        Ok(0)
    }
}

struct UartWrp(Uart<Data>);

impl std::ops::DerefMut for UartWrp {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.0
    }
}

impl std::ops::Deref for UartWrp {
    type Target = Uart<Data>;

    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

unsafe impl Send for UartWrp {}
unsafe impl Sync for UartWrp {}

struct FileServ(Mutex<UartWrp>);

impl file_rpc::Server for FileServ {
    fn read(
        &self,
        _fd: u64,
        _len: usize,
    ) -> std::result::Result<std::borrow::Cow<'_, [u8]>, Errno> {
        Err(Errno::ENOSYS)
    }

    fn write(&self, _fd: u64, data: &[u8]) -> Result<(), Errno> {
        let mut uart = self.0.lock();
        for &byte in data {
            while !uart.read_line_status().contains(LineStatus::TRANSMIT_EMPTY) {}
            uart.write_data(byte);
        }
        Ok(())
    }

    fn close(&self, _fd: u64) -> Result<(), Errno> { Ok(()) }

    fn size(&self, _fd: u64) -> Result<u64, Errno> {
        Err(Errno::ENOSYS)
    }

    fn dup(&self, fd: u64) -> Result<u64, Errno> {
        Ok(fd)
    }

    fn seek(&self, _fd: u64, _pos: file_rpc::SeekFrom) -> Result<u64, Errno> { Err(Errno::ESPIPE) }
}

fn main() {
    let uart = unsafe { init_uart(uart::COM1) };
    dev_driver_rpc::register_server(Box::new(DevServ));
    file_rpc::register_server(Box::new(FileServ(Mutex::new(UartWrp(uart)))));
    let devfs_pid;
    loop {
        if let Some(pid) = syscalls::try_get_registered(1) {
            devfs_pid = pid;
            break;
        }
    }
    devfs_rpc::Client::new(devfs_pid)
        .register_dev("ttyS0")
        .unwrap();
    loop {
        ipc::process_messages()
    }
}

/// Sets up the given UART for 115200 baud 8N1, no interrupts
unsafe fn init_uart(address: UartAddress) -> Uart<Data> {
    let mut uart = unsafe { Uart::new(address) }.configure_mode();
    uart.set_baud(Baud::B115200);
    let mut uart = uart.data_mode();
    let line_control = LineControl {
        bits: DataBits::Eight,
        parity: ParityMode::None,
        extra_stop: false,
        break_signal: false,
    };
    uart.write_line_control(line_control);
    uart.enable_fifo(true, true, false, FifoSize::Fourteen);
    // UART library misspelled modem here
    uart.write_model_control(ModemControl::TERMINAL_READY | ModemControl::REQUEST_TO_SEND);
    uart.write_interrupt_enable(InterruptEnable::empty());
    uart
}