use crate::handle::{ClientHandle, ServerHandle};
use crate::target_configure::{ClientTargetConfig, ServerTargetConfig};
use serde::{Deserialize, Serialize};
use std::{
    fmt::{Display, Formatter},
    marker::PhantomData,
    net::{AddrParseError, IpAddr, Ipv4Addr, SocketAddr},
    str::FromStr,
};
use tokio::net::lookup_host;

const DEFAULT_PORT: u16 = 8080;

#[derive(Debug, Serialize, Deserialize)]
pub struct TcpServerTarget<Client, Server>
where
    Client: ClientHandle<Server>,
    Server: ServerHandle<Client>,
{
    /// Client Config
    client_cfg: Option<ClientTargetConfig>,

    /// Server Config
    server_cfg: Option<ServerTargetConfig>,

    /// Server port
    port: u16,

    /// Bind addr
    bind_addr: IpAddr,

    /// Client Phantom Data
    _client: PhantomData<Client>,

    /// Server Phantom Data
    _server: PhantomData<Server>,
}

impl<Client, Server> Default for TcpServerTarget<Client, Server>
where
    Client: ClientHandle<Server>,
    Server: ServerHandle<Client>,
{
    fn default() -> Self {
        Self {
            client_cfg: None,
            server_cfg: None,
            port: DEFAULT_PORT,
            bind_addr: IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)),
            _client: PhantomData,
            _server: PhantomData,
        }
    }
}

impl<Client, Server> From<SocketAddr> for TcpServerTarget<Client, Server>
where
    Client: ClientHandle<Server>,
    Server: ServerHandle<Client>,
{
    /// Convert SocketAddr to TcpServerTarget
    fn from(value: SocketAddr) -> Self {
        Self {
            port: value.port(),
            bind_addr: value.ip(),
            ..Self::default()
        }
    }
}

impl<Client, Server> From<TcpServerTarget<Client, Server>> for SocketAddr
where
    Client: ClientHandle<Server>,
    Server: ServerHandle<Client>,
{
    /// Convert TcpServerTarget to SocketAddr
    fn from(val: TcpServerTarget<Client, Server>) -> Self {
        SocketAddr::new(val.bind_addr, val.port)
    }
}

impl<Client, Server> Display for TcpServerTarget<Client, Server>
where
    Client: ClientHandle<Server>,
    Server: ServerHandle<Client>,
{
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}:{}", self.bind_addr, self.port)
    }
}

impl<Client, Server> TcpServerTarget<Client, Server>
where
    Client: ClientHandle<Server>,
    Server: ServerHandle<Client>,
{
    /// Create target by address
    pub fn from_addr(addr: impl Into<IpAddr>, port: impl Into<u16>) -> Self {
        Self {
            port: port.into(),
            bind_addr: addr.into(),
            ..Self::default()
        }
    }

    /// Try to create target by string
    pub fn from_str<'a>(addr_str: impl Into<&'a str>) -> Result<Self, AddrParseError> {
        let socket_addr = SocketAddr::from_str(addr_str.into());
        match socket_addr {
            Ok(socket_addr) => Ok(Self::from_addr(socket_addr.ip(), socket_addr.port())),
            Err(err) => Err(err),
        }
    }

    /// Try to create target by domain name
    pub async fn from_domain<'a>(domain: impl Into<&'a str>) -> Result<Self, std::io::Error> {
        match domain_to_addr(domain).await {
            Ok(domain_addr) => Ok(Self::from(domain_addr)),
            Err(e) => Err(e),
        }
    }

    /// Set client config
    pub fn client_cfg(mut self, config: ClientTargetConfig) -> Self {
        self.client_cfg = Some(config);
        self
    }

    /// Set server config
    pub fn server_cfg(mut self, config: ServerTargetConfig) -> Self {
        self.server_cfg = Some(config);
        self
    }

    /// Add client config
    pub fn add_client_cfg(&mut self, config: ClientTargetConfig) {
        self.client_cfg = Some(config);
    }

    /// Add server config
    pub fn add_server_cfg(&mut self, config: ServerTargetConfig) {
        self.server_cfg = Some(config);
    }

    /// Get client config ref
    pub fn get_client_cfg(&self) -> Option<&ClientTargetConfig> {
        self.client_cfg.as_ref()
    }

    /// Get server config ref
    pub fn get_server_cfg(&self) -> Option<&ServerTargetConfig> {
        self.server_cfg.as_ref()
    }

    /// Get SocketAddr of TcpServerTarget
    pub fn get_addr(&self) -> SocketAddr {
        SocketAddr::new(self.bind_addr, self.port)
    }
}

/// Parse Domain Name to IpAddr via DNS
async fn domain_to_addr<'a>(domain: impl Into<&'a str>) -> Result<SocketAddr, std::io::Error> {
    let domain = domain.into();
    let default_port: u16 = DEFAULT_PORT;

    if let Ok(socket_addr) = domain.parse::<SocketAddr>() {
        return Ok(match socket_addr.ip() {
            IpAddr::V4(_) => socket_addr,
            IpAddr::V6(_) => SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), socket_addr.port()),
        });
    }

    if let Ok(_v6_addr) = domain.parse::<std::net::Ipv6Addr>() {
        return Ok(SocketAddr::new(
            IpAddr::V4(Ipv4Addr::LOCALHOST),
            default_port,
        ));
    }

    let (host, port_str) = if let Some((host, port)) = domain.rsplit_once(':') {
        (host.trim_matches(|c| c == '[' || c == ']'), Some(port))
    } else {
        (domain, None)
    };

    let port = port_str
        .and_then(|p| p.parse::<u16>().ok())
        .map(|p| p.clamp(0, u16::MAX))
        .unwrap_or(default_port);

    let mut socket_iter = lookup_host((host, 0)).await?;

    if let Some(addr) = socket_iter.find(|addr| addr.is_ipv4()) {
        return Ok(SocketAddr::new(addr.ip(), port));
    }

    Ok(SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), port))
}