// SPDX-FileCopyrightText: 2020 Sean Cross <sean@xobs.io>
// SPDX-License-Identifier: Apache-2.0

#[cfg(baremetal)]
use core::fmt::{Error, Write};
#[cfg(baremetal)]
use utralib::generated::*;

#[macro_use]
#[cfg(all(
    not(test),
    baremetal,
    any(feature = "debug-print", feature = "print-panics")
))]
pub mod debug_print_hardware {
    // the HW device mapping is done in main.rs/init(); the virtual address has to be in the top 4MiB as it is the only page shared among all processes
    pub const SUPERVISOR_UART_ADDR: *mut usize = 0xffcf_0000 as *mut usize; // see https://github.com/betrusted-io/xous-core/blob/master/docs/memory.md

    #[macro_export]
    macro_rules! print
    {
        ($($args:tt)+) => ({
                use core::fmt::Write;
                let _ = write!(crate::debug::Uart {}, $($args)+);
        });
    }
}
#[cfg(all(
    not(test),
    baremetal,
    any(feature = "debug-print", feature = "print-panics")
))]
pub use crate::debug::debug_print_hardware::SUPERVISOR_UART_ADDR;

#[cfg(all(
    not(test),
    baremetal,
    not(any(feature = "debug-print", feature = "print-panics"))
))]
#[macro_export]
macro_rules! print {
    ($($args:tt)+) => {{
        ()
    }};
}

#[cfg(baremetal)]
#[macro_export]
macro_rules! println
{
	() => ({
		print!("\r\n")
	});
	($fmt:expr) => ({
		print!(concat!($fmt, "\r\n"))
	});
	($fmt:expr, $($args:tt)+) => ({
		print!(concat!($fmt, "\r\n"), $($args)+)
	});
}

#[cfg(baremetal)]
pub struct Uart {
    // pub base: *mut usize,
}
#[cfg(baremetal)]
static mut INITIALIZED: bool = false;

#[cfg(all(baremetal, feature = "wrap-print"))]
static mut CHAR_COUNT: usize = 0;

#[cfg(baremetal)]
impl Uart {
    #[allow(dead_code)]
    pub fn init(self) {
        unsafe { INITIALIZED = true };
        let mut uart_csr = CSR::new(0xffcf_0000 as *mut u32);
        uart_csr.rmwf(utra::uart::EV_ENABLE_RX, 1);
    }

    pub fn putc(&self, c: u8) {
        if unsafe { INITIALIZED != true } {
            return;
        }

        let mut uart_csr = CSR::new(0xffcf_0000 as *mut u32);
        // Wait until TXFULL is `0`
        while uart_csr.r(utra::uart::TXFULL) != 0 {
            ()
        }
        #[cfg(feature = "wrap-print")]
        unsafe {
            if c == b'\n' {
                CHAR_COUNT = 0;
            } else if CHAR_COUNT > 80 {
                CHAR_COUNT = 0;
                self.putc(b'\n');
                self.putc(b'\r');
                self.putc(b' ');
                self.putc(b' ');
                self.putc(b' ');
                self.putc(b' ');
            } else {
                CHAR_COUNT += 1;
            }
        }
        uart_csr.wfo(utra::uart::RXTX_RXTX, c as u32);
    }

    #[allow(dead_code)]
    pub fn getc(&self) -> Option<u8> {
        let mut uart_csr = CSR::new(0xffcf_0000 as *mut u32);
        // If EV_PENDING_RX is 1, return the pending character.
        // Otherwise, return None.
        match uart_csr.rf(utra::uart::EV_PENDING_RX) {
            0 => None,
            ack => {
                let c = Some(uart_csr.r(utra::uart::RXTX) as u8);
                uart_csr.wfo(utra::uart::EV_PENDING_RX, ack);
                c
            }
        }
    }
}

#[cfg(all(
    not(test),
    baremetal,
    any(feature = "debug-print", feature = "print-panics")
))]
pub fn irq(_irq_number: usize, _arg: *mut usize) {
    let pressed_key = Uart {}
        .getc()
        .expect("no character queued despite interrupt") as char;
    println!("Interrupt {}: Key pressed: {}", _irq_number, pressed_key,);
    match pressed_key {
        'm' => {
            println!("Printing memory page tables");
            crate::services::SystemServices::with(|system_services| {
                let current_pid = system_services.current_pid();
                for process in &system_services.processes {
                    if !process.free() {
                        println!("PID {} {}:", process.pid, system_services.process_name(process.pid).unwrap_or(""));
                        process.activate().unwrap();
                        crate::arch::mem::MemoryMapping::current().print_map();
                        println!();
                    }
                }
                system_services
                    .get_process(current_pid)
                    .unwrap()
                    .activate()
                    .unwrap();
            });
        }
        'p' => {
            println!("Printing processes");
            crate::services::SystemServices::with(|system_services| {
                let current_pid = system_services.current_pid();
                for process in &system_services.processes {
                    if !process.free() {
                        println!("PID {} {}:", process.pid, system_services.process_name(process.pid).unwrap_or(""));
                        process.activate().unwrap();
                        crate::arch::process::Process::with_current_mut(|arch_process| {
                            arch_process.print_all_threads()
                        });
                        println!();
                    }
                }
                system_services
                    .get_process(current_pid)
                    .unwrap()
                    .activate()
                    .unwrap();
            });
        }
        'r' => {
            println!("RAM usage:");
            let mut total_bytes = 0;
            crate::services::SystemServices::with(|system_services| {
                crate::mem::MemoryManager::with(|mm| {
                    for process in &system_services.processes {
                        if !process.free() {
                            let bytes_used = mm.ram_used_by(process.pid);
                            total_bytes += bytes_used;
                            println!(
                                "    PID {:>3}: {:>4} k {}",
                                process.pid,
                                bytes_used / 1024,
                                system_services.process_name(process.pid).unwrap_or("")
                            );
                        }
                    }
                });
            });
            println!("{} k total", total_bytes / 1024);
        }
        'h' => {
            println!("Xous Kernel Debug");
            println!("key | command");
            println!("--- + -----------------------");
            println!(" r  | report RAM usage of all processes");
            println!(" p  | print all processes and threads");
            println!(" m  | print MMU page tables of all processes");
        }
        _ => {}
    }
}

#[cfg(baremetal)]
impl Write for Uart {
    fn write_str(&mut self, s: &str) -> Result<(), Error> {
        for c in s.bytes() {
            self.putc(c);
        }
        Ok(())
    }
}

#[cfg(feature = "debug-print")]
#[macro_export]
macro_rules! klog
{
	() => ({
		print!(" [{}:{}]", file!(), line!())
	});
	($fmt:expr) => ({
        print!(concat!(" [{}:{} ", $fmt, "]"), file!(), line!())
	});
	($fmt:expr, $($args:tt)+) => ({
		print!(concat!(" [{}:{} ", $fmt, "]"), file!(), line!(), $($args)+)
	});
}

#[cfg(not(feature = "debug-print"))]
#[macro_export]
macro_rules! klog {
    ($($args:tt)+) => {{
        ()
    }};
}