use core::fmt::Write;
use core::{cell::RefCell, fmt::Arguments};

use critical_section::{CriticalSection, Mutex};
use esp_hal::Blocking;
use esp_hal::clock::CpuClock;
use esp_hal::psram::{FlashFreq, PsramConfig, PsramSize, SpiRamFreq, SpiTimingConfigCoreClock};
use esp_hal::uart::UartTx;
use log::{LevelFilter, Log};

pub const LOG_LEVEL_FILTER: LevelFilter = {
    if let Some(string) = option_env!("ESP_LOG") {
        if string.eq_ignore_ascii_case("ERROR") {
            LevelFilter::Error
        } else if string.eq_ignore_ascii_case("WARN") {
            LevelFilter::Warn
        } else if string.eq_ignore_ascii_case("INFO") {
            LevelFilter::Info
        } else if string.eq_ignore_ascii_case("DEBUG") {
            LevelFilter::Debug
        } else if string.eq_ignore_ascii_case("TRACE") {
            LevelFilter::Trace
        } else {
            panic!(
                "Unknown `ESP_LOG` value. Only `ERROR`, `WARN`, `INFO`, `DEBUG`, `TRACE`, or `OFF` may be used."
            );
        }
    } else {
        LevelFilter::Off
    }
};

const RESET: &str = "\u{001B}[0m";
const RED: &str = "\u{001B}[31m";
const GREEN: &str = "\u{001B}[32m";
const YELLOW: &str = "\u{001B}[33m";
const BLUE: &str = "\u{001B}[34m";
const CYAN: &str = "\u{001B}[35m";

fn with_formatted_log_record<R>(
    record: &log::Record,
    callback: impl FnOnce(Arguments<'_>) -> R,
) -> R {
    let color = match record.level() {
        log::Level::Error => RED,
        log::Level::Warn => YELLOW,
        log::Level::Info => GREEN,
        log::Level::Debug => BLUE,
        log::Level::Trace => CYAN,
    };
    let args = format_args!(
        "{}{:>5} - {}{}\n",
        color,
        record.level(),
        record.args(),
        RESET
    );
    (callback)(args)
}

/// The default USB logger.
#[cfg(feature = "usb-log")]
pub mod usb {
    use super::*;

    pub fn setup_logging() -> impl Future<Output = ()> {
        esp_println::logger::init_logger(LOG_LEVEL_FILTER);
        log::info!("Logger initialized!");
        async {}
    }
}

/// Alternative logger via UART.
#[cfg(feature = "alt-log")]
pub mod uart {
    use super::*;
    use crate::console;
    use core::{cell::RefCell, fmt::Write};
    use critical_section::{CriticalSection, Mutex};
    use esp_hal::{
        Blocking,
        gpio::interconnect::{PeripheralInput, PeripheralOutput},
        peripherals::UART2,
        uart::{Uart, UartTx},
    };
    use log::{Log, info};

    static ALT_LOGGER_UART: Mutex<RefCell<Option<UartTx<'static, Blocking>>>> =
        Mutex::new(RefCell::new(None));

    pub fn with_uart_tx<R>(
        f: impl FnOnce(CriticalSection<'_>, &'_ mut UartTx<'static, Blocking>) -> R,
    ) -> R {
        critical_section::with(|cs| {
            let mut uart = ALT_LOGGER_UART.borrow(cs).borrow_mut();
            let uart = uart.as_mut().unwrap();

            (f)(cs, uart)
        })
    }

    #[allow(unused)]
    macro_rules! println {
        // TODO: I don't think this is necessary. Consider removing.
        // () => {{
        //     do_print(Default::default());
        // }};

        ($($arg:tt)*) => {{
            do_print(::core::format_args!($($arg)*));
        }};
    }

    #[allow(unused)]
    fn do_print(args: core::fmt::Arguments<'_>) {
        with_uart_tx(|_, uart| {
            uart.write_fmt(format_args!("{}\n", args)).unwrap();
            uart.flush().unwrap();
        })
    }

    struct UartLogger;

    impl Log for UartLogger {
        #[allow(unused)]
        fn enabled(&self, _: &log::Metadata) -> bool {
            // Filtered by `log` already
            true
        }

        #[allow(unused)]
        fn log(&self, record: &log::Record) {
            with_uart_tx(|cs, uart| {
                with_formatted_log_record(record, |args| uart.write_fmt(args)).unwrap();
                uart.flush().unwrap();
            })
        }

        fn flush(&self) {}
    }

    #[panic_handler]
    fn panic_handler(info: &core::panic::PanicInfo) -> ! {
        use super::{RED, RESET};
        use esp_backtrace::Backtrace;

        println!("{RED}");
        println!("=============== CUSTOM PANIC HANDLER ==============");
        println!("{info}{RESET}");
        println!("");
        println!("Backtrace:");
        println!("");

        let backtrace = Backtrace::capture();

        for frame in backtrace.frames() {
            println!("0x{:x}", frame.program_counter());
        }

        loop {}
    }

    pub fn setup_logging(
        uart: impl esp_hal::uart::Instance + 'static,
        tx: impl PeripheralOutput<'static>,
        rx: impl PeripheralInput<'static>,
    ) -> impl Future<Output = ()> {
        let (uart_rx, uart_tx) = Uart::new(uart, Default::default())
            .unwrap()
            .with_tx(tx)
            .with_rx(rx)
            .split();

        critical_section::with(|cs| {
            *ALT_LOGGER_UART.borrow(cs).borrow_mut() = Some(uart_tx);
        });

        unsafe {
            log::set_logger_racy(&UartLogger).unwrap();
            log::set_max_level_racy(LOG_LEVEL_FILTER);
        }

        info!("Logger initialized!");
        console::run_console(uart_rx.into_async())
    }
}

/// Logging via RTT for probe-rs.
#[cfg(feature = "rtt-log")]
pub mod rtt {
    use super::*;
    #[allow(unused)]
    use ::rtt_target::{rprint as print, rprintln as println};
    use panic_rtt_target as _; // Use the RTT panic handler.
    use rtt_target::ChannelMode;

    pub fn setup_logging() -> impl Future<Output = ()> {
        rtt_target::rtt_init_log!(LOG_LEVEL_FILTER, ChannelMode::BlockIfFull);
        log::info!("Logger initialized!");
        async {}
    }
}