#![no_std]
#![no_main]

extern crate panic_itm;
use cortex_m::{iprintln, iprint};

use embedded_hal::{
    digital::v2::OutputPin,
    blocking::delay::DelayMs
};
use stm32f4xx_hal::{
    rcc::RccExt,
    gpio::GpioExt,
    time::U32Ext,
    stm32::ITM,
    delay::Delay,
    spi::Spi,
    time::Hertz
};
use enc424j600::EthPhy;

///
use stm32f4xx_hal::{
    stm32::SPI1,
    gpio::{
        gpioa::{PA5, PA6, PA7, PA4},
        Alternate, AF5, Output, PushPull
    },
};
type SpiEth = enc424j600::Enc424j600<
    Spi<SPI1, (PA5<Alternate<AF5>>, PA6<Alternate<AF5>>, PA7<Alternate<AF5>>)>,
    PA4<Output<PushPull>>
>;

#[rtic::app(device = stm32f4xx_hal::stm32, peripherals = true, monotonic = rtic::cyccnt::CYCCNT)]
const APP: () = {
    struct Resources {
        spi_eth: SpiEth,
        delay: Delay,
        itm: ITM,
    }

    #[init()]
    fn init(mut c: init::Context) -> init::LateResources {
        c.core.SCB.enable_icache();
        c.core.SCB.enable_dcache(&mut c.core.CPUID);

        let clocks = c.device.RCC.constrain()
            .cfgr
            .sysclk(168.mhz())
            .hclk(168.mhz())
            .pclk2(42.mhz())        // used by SPI1
            .require_pll48clk()
            .freeze();
        let mut delay = Delay::new(c.core.SYST, clocks);

        // Init ITM
        let mut itm = c.core.ITM;
        let stim0 = &mut itm.stim[0];
        iprintln!(stim0,
            "Eth TX Pinging on STM32-F407 via NIC100/ENC424J600");

        // NIC100 / ENC424J600 Set-up
        let spi1 = c.device.SPI1;
        let gpioa = c.device.GPIOA.split();
        // Mapping: see Table 9, STM32F407ZG Manual
        let spi1_sck = gpioa.pa5.into_alternate_af5();
        let spi1_miso = gpioa.pa6.into_alternate_af5();
        let spi1_mosi = gpioa.pa7.into_alternate_af5();
        let spi1_nss = gpioa.pa4.into_push_pull_output();
        // Map SPISEL: see Table 1, NIC100 Manual
        let mut spisel = gpioa.pa1.into_push_pull_output();
        spisel.set_high().unwrap();
        delay.delay_ms(1_u32);
        spisel.set_low().unwrap();
        // Create SPI1 for HAL
        let mut spi_eth = {
            let spi_eth_port = Spi::spi1(
                spi1, (spi1_sck, spi1_miso, spi1_mosi),
                enc424j600::spi::interfaces::SPI_MODE,
                10_500_000.hz(),    // PCLK2 @ 42MHz, set SPI1 baud rate as f_PCLK2 divided by 4
                clocks);

            SpiEth::new(spi_eth_port, spi1_nss)
                .cpu_freq_mhz(168)
        };

        // Init
        match spi_eth.reset(&mut delay) {
            Ok(_) => {
                iprintln!(stim0, "Initializing Ethernet...")
            }
            Err(_) => {
                panic!("Ethernet initialization failed!")
            }
        }

        // Read MAC
        let mut eth_mac_addr: [u8; 6] = [0; 6];
        spi_eth.read_mac_addr(&mut eth_mac_addr);
        for i in 0..6 {
            let byte = eth_mac_addr[i];
            match i {
                0 => iprint!(stim0, "MAC Address = {:02x}-", byte),
                1..=4 => iprint!(stim0, "{:02x}-", byte),
                5 => iprint!(stim0, "{:02x}\n", byte),
                _ => ()
            };
        }

        // Init Rx/Tx buffers
        spi_eth.init_rxbuf();
        spi_eth.init_txbuf();
        iprintln!(stim0, "Ethernet controller initialized");

        init::LateResources {
            spi_eth,
            delay,
            itm,
        }
    }

    #[idle(resources=[spi_eth, delay, itm])]
    fn idle(c: idle::Context) -> ! {
        let stim0 = &mut c.resources.itm.stim[0];
        // Testing Eth TX
        let eth_tx_dat: [u8; 64] = [
            0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x08, 0x60,
            0x6e, 0x44, 0x42, 0x95, 0x08, 0x06, 0x00, 0x01,
            0x08, 0x00, 0x06, 0x04, 0x00, 0x01, 0x08, 0x60,
            0x6e, 0x44, 0x42, 0x95, 0xc0, 0xa8, 0x01, 0x64,
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc0, 0xa8,
            0x01, 0xe7, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0x00, 0x00, 0x00, 0x00, 0x69, 0xd0, 0x85, 0x9f
        ];
        loop {
            let mut eth_tx_packet = enc424j600::tx::TxPacket::new();
            eth_tx_packet.update_frame(&eth_tx_dat, 64);
            iprint!(stim0,
                "Sending packet (len={:}): ", eth_tx_packet.get_frame_length());
            for i in 0..20 {
                let byte = eth_tx_packet.get_frame_byte(i);
                match i {
                    0 => iprint!(stim0, "dest={:02x}-", byte),
                    6 => iprint!(stim0, "src={:02x}-", byte),
                    12 => iprint!(stim0, "data={:02x}", byte),
                    1..=4 | 7..=10 => iprint!(stim0, "{:02x}-", byte),
                    13..=14 | 16..=18 => iprint!(stim0, "{:02x}", byte),
                    5 | 11 | 15 => iprint!(stim0, "{:02x} ", byte),
                    19 => iprint!(stim0, "{:02x} ...\n", byte),
                    _ => ()
                };
            }
            c.resources.spi_eth.send_packet(&eth_tx_packet);
            iprintln!(stim0, "Packet sent");
            c.resources.delay.delay_ms(100_u32);
        }
    }
};