pub mod bond;
pub mod bridge;
pub mod ethernet;
pub mod gre;
pub mod ipip;
pub mod loopback;
pub mod qdisc;
pub mod stp;
pub mod tun;
pub mod vlan;
pub mod vxlan;

use std::rc::Rc;

use smoltcp::time::Instant;
use smoltcp::wire::{EthernetAddress, IpAddress, IpCidr};

/// Represent a link layer device (eth0, loopback...)
pub trait LinkDevice {
    /// Send the given packet to the machine with the `next_hop` ip address
    /// This method cannot fail so it's the implementor responsability
    /// to buffer packets which can't be sent immediatly or decide to
    /// drop them if necessary
    fn send(&mut self, next_hop: IpAddress, packet: &[u8], now: Instant);

    /// Returns None if nothing is received.
    /// Returns an Ip packet otherwise
    fn recv(&mut self, now: Instant) -> Option<&[u8]>;

    /// Returns the LinkDevice display name used to refer to it and for lookups
    fn name(&self) -> &Rc<str>;

    /// Returns wether this device have packets pending
    fn can_recv(&self) -> bool;

    fn mac_address(&self) -> Option<EthernetAddress>;
    fn set_mac_address(&mut self, addr: EthernetAddress);

    fn ip_address(&self) -> Option<IpCidr>;
    fn set_ip_address(&mut self, addr: IpCidr);

    fn arp_table(&self) -> String {
        String::new()
    }

    fn flush_arp(&mut self) {}

    fn arp_stats(&self) -> String {
        String::new()
    }

    fn qdisc_info(&self) -> String {
        "none\n".to_string()
    }

    fn set_qdisc(&mut self, _kind: &str) -> Result<(), String> {
        Err("qdisc configuration not supported on this device\n".to_string())
    }

    fn add_static_neighbor(&mut self, _ip: IpAddress, _mac: [u8; 6]) -> Result<(), String> {
        Err("static ARP entry not supported on this device\n".to_string())
    }

    fn remove_neighbor(&mut self, _ip: IpAddress) -> bool {
        false
    }

    fn is_promiscuous(&self) -> bool {
        false
    }

    fn set_promiscuous(&mut self, _enabled: bool) {}

    fn mtu(&self) -> usize {
        1500
    }

    fn set_mtu(&mut self, _mtu: usize) {}

    fn is_enabled(&self) -> bool {
        true
    }

    fn set_enabled(&mut self, _enabled: bool) {}

    fn link_state(&self) -> &'static str {
        "unknown"
    }

    fn statistics(&self) -> Stats {
        Stats::default()
    }
}

#[derive(Debug, Default, Clone, Copy)]
pub struct Stats {
    pub rx_bytes: u64,
    pub rx_packets: u64,
    pub tx_bytes: u64,
    pub tx_packets: u64,
    pub rx_errors: u64,
    pub tx_errors: u64,
    pub rx_dropped: u64,
    pub tx_dropped: u64,
}

#[derive(Default)]
pub struct DeviceList {
    inner: Vec<Box<dyn LinkDevice>>,
}

impl DeviceList {
    pub fn push<T: LinkDevice + 'static>(&mut self, dev: T) {
        self.inner.push(Box::new(dev))
    }

    pub fn get(&self, device_name: &str) -> Option<&dyn LinkDevice> {
        self.inner
            .iter()
            .find(|dev| dev.name().as_ref() == device_name)
            .map(|device| device.as_ref())
    }

    pub fn get_mut(&mut self, device_name: &str) -> Option<&mut (dyn LinkDevice + 'static)> {
        self.inner
            .iter_mut()
            .find(|dev| dev.name().as_ref() == device_name)
            .map(|device| device.as_mut())
    }

    pub fn iter(&self) -> impl Iterator<Item = &(dyn LinkDevice + 'static)> {
        self.inner.iter().map(|b| b.as_ref())
    }

    pub fn iter_mut(&mut self) -> impl Iterator<Item = &mut (dyn LinkDevice + 'static)> {
        self.inner.iter_mut().map(|b| b.as_mut())
    }
}