use nix::sys::socket::{AddressFamily, SockaddrLike};
use std::collections::HashMap;
use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
use std::str::FromStr;
use sysinfo::Networks;

pub fn extract_ipv4(ip: IpAddr) -> Ipv4Addr {
    match ip {
        IpAddr::V4(i) => i,
        IpAddr::V6(_) => {
            panic!("IPv6 found in IPv4 definition!")
        }
    }
}

pub fn extract_ipv6(ip: IpAddr) -> Ipv6Addr {
    match ip {
        IpAddr::V4(_) => {
            panic!("IPv4 found in IPv6 definition!")
        }
        IpAddr::V6(i) => i,
    }
}

pub fn is_ipv4_address_valid<D: AsRef<str>>(ip: D) -> bool {
    Ipv4Addr::from_str(ip.as_ref()).is_ok()
}

pub fn is_ipv6_address_valid<D: AsRef<str>>(ip: D) -> bool {
    Ipv6Addr::from_str(ip.as_ref()).is_ok()
}

pub fn is_ipv4_mask_valid(mask: u8) -> bool {
    mask <= 32
}

pub fn is_ipv6_mask_valid(mask: u8) -> bool {
    mask <= 128
}

pub fn is_mask_valid(ipv: usize, mask: u8) -> bool {
    match ipv {
        4 => is_ipv4_mask_valid(mask),
        6 => is_ipv6_mask_valid(mask),
        _ => panic!("Unsupported IP version"),
    }
}

pub fn is_mac_address_valid<D: AsRef<str>>(mac: D) -> bool {
    lazy_regex::regex!("^([a-fA-F0-9]{2}[:-]){5}[a-fA-F0-9]{2}$").is_match(mac.as_ref())
}

pub fn is_net_interface_name_valid<D: AsRef<str>>(int: D) -> bool {
    lazy_regex::regex!("^[a-zA-Z0-9]+$").is_match(int.as_ref())
}

/// Get the list of available network interfaces
pub fn net_list() -> Vec<String> {
    let mut networks = Networks::new();
    networks.refresh_list();

    networks
        .list()
        .iter()
        .map(|n| n.0.to_string())
        .collect::<Vec<_>>()
}

/// Get the list of available network interfaces associated with their IP address
pub fn net_list_and_ips() -> anyhow::Result<HashMap<String, Vec<IpAddr>>> {
    let addrs = nix::ifaddrs::getifaddrs().unwrap();

    let mut res = HashMap::new();

    for ifaddr in addrs {
        let address = match ifaddr.address {
            Some(address) => address,
            None => {
                log::debug!(
                    "Interface {} has an unsupported address family",
                    ifaddr.interface_name
                );
                continue;
            }
        };

        let addr_str = match address.family() {
            Some(AddressFamily::Inet) => {
                let address = address.to_string();
                address
                    .split_once(':')
                    .map(|a| a.0)
                    .unwrap_or(&address)
                    .to_string()
            }
            Some(AddressFamily::Inet6) => {
                let address = address.to_string();
                let address = address
                    .split_once(']')
                    .map(|a| a.0)
                    .unwrap_or(&address)
                    .to_string();

                let address = address
                    .split_once('%')
                    .map(|a| a.0)
                    .unwrap_or(&address)
                    .to_string();

                address.strip_prefix('[').unwrap_or(&address).to_string()
            }
            _ => {
                log::debug!(
                    "Interface {} has an unsupported address family {:?}",
                    ifaddr.interface_name,
                    address.family()
                );
                continue;
            }
        };

        log::debug!(
            "Process ip {addr_str} for interface {}",
            ifaddr.interface_name
        );

        let ip = IpAddr::from_str(&addr_str)?;

        if !res.contains_key(&ifaddr.interface_name) {
            res.insert(ifaddr.interface_name.to_string(), Vec::with_capacity(1));
        }

        res.get_mut(&ifaddr.interface_name).unwrap().push(ip);
    }

    Ok(res)
}

#[cfg(test)]
mod tests {
    use crate::utils::net_utils::{
        is_ipv4_address_valid, is_ipv6_address_valid, is_mac_address_valid, is_mask_valid,
        is_net_interface_name_valid,
    };

    #[test]
    fn test_is_mac_address_valid() {
        assert!(is_mac_address_valid("FF:FF:FF:FF:FF:FF"));
        assert!(is_mac_address_valid("02:42:a4:6e:f2:be"));

        assert!(!is_mac_address_valid("tata"));
        assert!(!is_mac_address_valid("FF:FF:FF:FF:FF:FZ"));
        assert!(!is_mac_address_valid("FF:FF:FF:FF:FF:FF:FF"));
    }

    #[test]
    fn test_is_ipv4_address_valid() {
        assert!(is_ipv4_address_valid("10.0.0.1"));
        assert!(is_ipv4_address_valid("2.56.58.156"));

        assert!(!is_ipv4_address_valid("tata"));
        assert!(!is_ipv4_address_valid("1.25.25.288"));
        assert!(!is_ipv4_address_valid("5.5.5.5.5"));
        assert!(!is_ipv4_address_valid("fe80::"));
    }

    #[test]
    fn test_is_ipv6_address_valid() {
        assert!(is_ipv6_address_valid("fe80::"));
        assert!(is_ipv6_address_valid("fe80:dd::"));
        assert!(is_ipv6_address_valid("00:00:00:00:00::"));
        assert!(is_ipv6_address_valid("0:0:0:0:0:0:0:0"));

        assert!(!is_ipv6_address_valid("tata"));
        assert!(!is_ipv6_address_valid("2.56.58.156"));
        assert!(!is_ipv6_address_valid("fe::dd::dd"));
    }

    #[test]
    fn test_is_mask_valid() {
        assert!(is_mask_valid(4, 25));
        assert!(is_mask_valid(4, 32));
        assert!(is_mask_valid(6, 32));
        assert!(is_mask_valid(6, 34));

        assert!(!is_mask_valid(4, 34));
        assert!(is_mask_valid(6, 69));
        assert!(is_mask_valid(6, 128));
        assert!(!is_mask_valid(6, 129));
    }

    #[test]
    fn test_is_net_interface_name_valid() {
        assert!(is_net_interface_name_valid("eth0"));
        assert!(is_net_interface_name_valid("enp0s25"));

        assert!(!is_net_interface_name_valid("enp0s25 "));
        assert!(!is_net_interface_name_valid("@enp0s25 "));
    }
}