#![cfg(any(feature = "cgi", feature = "scgi"))]
use std::collections::HashMap;
use std::io;
use std::net::SocketAddr;

#[cfg(feature = "cgi")]
use tokio::process::Command;
#[cfg(feature = "cgi")]
use std::path::PathBuf;

#[cfg(feature = "scgi")]
use std::net::ToSocketAddrs;
#[cfg(feature = "scgi")]
use tokio::io::{AsyncReadExt, AsyncWriteExt};
#[cfg(feature = "scgi")]
use tokio::net::TcpStream;

use crate::config;
use crate::conn;
use crate::logger;
use crate::status::Status;

#[cfg(any(feature = "cgi", feature = "scgi"))]
fn envs(peer_addr: SocketAddr, srv: &config::ServerCfg, url: &url::Url) -> HashMap<String, String> {
    let mut envs = HashMap::new();
    envs.insert("GATEWAY_INTERFACE".to_string(), "CGI/1.1".to_string());
    envs.insert("GEMINI_URL".to_string(), url.to_string());
    envs.insert("SERVER_NAME".to_string(), url.host_str().unwrap().to_string());
    envs.insert("SERVER_PROTOCOL".to_string(), "GEMINI".to_string());
    let addr = peer_addr.ip().to_string();
    envs.insert("REMOTE_ADDR".to_string(), addr.clone());
    envs.insert("REMOTE_HOST".to_string(), addr);
    let port = peer_addr.port().to_string();
    envs.insert("REMOTE_PORT".to_string(), port);
    envs.insert("SERVER_SOFTWARE".to_string(), env!("CARGO_PKG_NAME").to_string());

    if let Some(q) = url.query() {
        envs.insert("QUERY_STRING".to_string(), q.to_string());
    }

    match &srv.server.cgienv {
        Some(c) => {
            for (k, v) in c.iter() {
                envs.insert(k.clone(), v.clone());
            }
        }
        None => {}
    }
    envs
}

#[cfg(any(feature = "cgi", feature = "scgi"))]
fn check(byt: u8, peer_addr: SocketAddr, u: url::Url) -> bool {
    match byt {
        49 => {
            logger::logger(peer_addr, Status::Input, u.as_str());
        },
        50 => {
            logger::logger(peer_addr, Status::Success, u.as_str());
        },
        51..=54 => {}
        _ => {
            logger::logger(peer_addr, Status::CGIError, u.as_str());
            return false;
        },
    }
    true
}

#[cfg(feature = "cgi")]
pub async fn cgi(
    mut con: conn::Connection,
    srv: &config::ServerCfg,
    path: PathBuf,
    url: url::Url,
) -> Result<(), io::Error> {
    let mut envs = envs(con.peer_addr, srv, &url);
    envs.insert("SCRIPT_NAME".to_string(), path.file_name().unwrap().to_str().unwrap().to_string());

    match path.parent() {
        Some(p) => {
            std::env::set_current_dir(p)?;
        },
        None => {},
    }

    let cmd = Command::new(path.to_str().unwrap())
        .env_clear()
        .envs(&envs)
        .output();
    
    let cmd = match tokio::time::timeout(tokio::time::Duration::from_secs(5), cmd).await {
        Ok(c) => {
            match c {
                Ok(cc) => cc,

                Err(_) => {
                    logger::logger(con.peer_addr, Status::CGIError, url.as_str());
                    con.send_status(Status::CGIError, None).await?;
                    return Ok(());
                },
            }
        },
        Err(_) => {
            logger::logger(con.peer_addr, Status::CGIError, url.as_str());
            con.send_status(Status::CGIError, None).await?;
            return Ok(());
        },
    };

    if !cmd.status.success() {
        logger::logger(con.peer_addr, Status::CGIError, url.as_str());
        con.send_status(Status::CGIError, None).await?;
        return Ok(());
    }
    let cmd = String::from_utf8(cmd.stdout).unwrap();
    if !check(cmd.as_bytes()[0], con.peer_addr, url) {
        con.send_status(Status::CGIError, None).await?;
        return Ok(());
    }
    
    con.send_raw(cmd.as_bytes()).await?;
    return Ok(());
}

#[cfg(feature = "scgi")]
pub async fn scgi(addr: String, u: url::Url, mut con: conn::Connection, srv: &config::ServerCfg) -> Result<(), io::Error> {
    let addr = addr
        .to_socket_addrs()?
        .next()
        .ok_or_else(|| io::Error::from(io::ErrorKind::AddrNotAvailable))?;

    let mut stream = match TcpStream::connect(&addr).await {
        Ok(s) => s,
        Err(_) => {
            logger::logger(con.peer_addr, Status::CGIError, u.as_str());
            con.send_status(Status::CGIError, None).await?;
            return Ok(());
        }
    };
    let envs = envs(con.peer_addr, srv, &u);
    let len = 0usize;
    let mut byt = String::from(format!("CONTENT_LENGTH\x00{}\x00SCGI\x001\x00
        RQUEST_METHOD\x00POST\x00REQUEST_URI\x00{}\x00", len, u.path()));
    for (k, v) in envs.iter() {
        byt.push_str(&format!("{}\x00{}\x00", k, v));
    }
    byt = byt.len().to_string() + ":" + &byt + ",";
    
    stream.write_all(byt.as_bytes()).await?;
    stream.flush().await?;

    let mut buf = vec![];
    if let Err(_) = tokio::time::timeout(
        tokio::time::Duration::from_secs(5), stream.read_to_end(&mut buf)).await {
        logger::logger(con.peer_addr, Status::CGIError, u.as_str());
        con.send_status(Status::CGIError, None).await?;
        return Ok(());
    }
    let req = String::from_utf8_lossy(&buf[..]);
    if !check(req.as_bytes()[0], con.peer_addr, u) {
        con.send_status(Status::CGIError, None).await?;
        return Ok(());
    }

    con.send_raw(req.as_bytes()).await?;
    Ok(())
}