//! Dump the EEPROM of a given sub device to stdout.

use env_logger::Env;
use ethercrab::{
    MainDevice, MainDeviceConfig, PduStorage, Timeouts, error::Error, std::ethercat_now,
};
use std::io::Write;

/// Maximum number of SubDevices that can be stored. This must be a power of 2 greater than 1.
const MAX_SUBDEVICES: usize = 16;
/// Maximum PDU data payload size - set this to the max PDI size or higher.
const MAX_PDU_DATA: usize = PduStorage::element_size(1100);
/// Maximum number of EtherCAT frames that can be in flight at any one time.
const MAX_FRAMES: usize = 16;
/// Maximum total PDI length.
const PDI_LEN: usize = 64;

static PDU_STORAGE: PduStorage<MAX_FRAMES, MAX_PDU_DATA> = PduStorage::new();

fn main() -> Result<(), Error> {
    smol::block_on(async {
        env_logger::Builder::from_env(Env::default().default_filter_or("info")).init();

        let interface = std::env::args()
            .nth(1)
            .expect("Provide network interface as first argument.");

        let index: u16 = std::env::args()
            .nth(2)
            .expect("Provide device index (starting from zero) as second argument.")
            .parse()
            .expect("Invalid index: must be a number");

        log::info!(
            "Starting EEPROM dump tool, interface {}, device index {}",
            interface,
            index
        );

        let (tx, rx, pdu_loop) = PDU_STORAGE.try_split().expect("can only split once");

        let maindevice = MainDevice::new(
            pdu_loop,
            Timeouts::default(),
            MainDeviceConfig {
                dc_static_sync_iterations: 0,
                ..MainDeviceConfig::default()
            },
        );

        #[cfg(target_os = "windows")]
        std::thread::spawn(move || {
            ethercrab::std::tx_rx_task_blocking(
                &interface,
                tx,
                rx,
                ethercrab::std::TxRxTaskConfig { spinloop: false },
            )
            .expect("TX/RX task")
        });
        #[cfg(not(target_os = "windows"))]
        smol::spawn(ethercrab::std::tx_rx_task(&interface, tx, rx).expect("spawn TX/RX task"))
            .detach();

        let group = maindevice
            .init_single_group::<MAX_SUBDEVICES, PDI_LEN>(ethercat_now)
            .await
            .expect("Init");

        log::info!("Discovered {} SubDevices", group.len());

        for subdevice in group.iter(&maindevice) {
            log::info!(
                "--> SubDevices {:#06x} {} {}",
                subdevice.configured_address(),
                subdevice.name(),
                subdevice.identity()
            );
        }

        let subdevice = group
            .subdevice(&maindevice, usize::from(index))
            .expect("Could not find device for given index");

        log::info!(
            "Dumping EEPROM for device index {}: {:#06x} {} {} {}...",
            index,
            subdevice.configured_address(),
            subdevice.name(),
            subdevice
                .description()
                .await?
                .map(|d| d.as_str().to_string())
                .unwrap_or(String::new()),
            subdevice.identity()
        );

        let eeprom_len = subdevice
            .eeprom_size(&maindevice)
            .await
            .expect("Could not read EEPROM len");

        log::info!("--> Device EEPROM is {} bytes long", eeprom_len);

        let mut buf = vec![0u8; eeprom_len];

        // Read entire EEPROM into buffer
        subdevice.eeprom_read_raw(&maindevice, 0, &mut buf).await?;

        std::io::stdout().write_all(&buf[..]).expect("Stdout write");

        log::info!("Done, wrote {} bytes to stdout", buf.len());

        Ok(())
    })
}