use std::str;
use std::sync::Arc;

use peanuts::element::{FromElement, IntoElement};
use peanuts::{Reader, Writer};
use rsasl::prelude::SASLConfig;
use tokio::io::{AsyncRead, AsyncWrite, AsyncWriteExt, BufReader, ReadHalf, WriteHalf};
use tokio_native_tls::native_tls::TlsConnector;
use tracing::{debug, info, instrument, trace};
use trust_dns_resolver::proto::rr::domain::IntoLabel;

use crate::connection::{Tls, Unencrypted};
use crate::error::Error;
use crate::stanza::starttls::{Proceed, StartTls};
use crate::stanza::stream::{Features, Stream};
use crate::stanza::XML_VERSION;
use crate::Result;
use crate::JID;

pub struct Jabber<S>
where
    S: AsyncRead + AsyncWrite + Unpin,
{
    reader: Reader<ReadHalf<S>>,
    writer: Writer<WriteHalf<S>>,
    jid: Option<JID>,
    auth: Option<Arc<SASLConfig>>,
    server: String,
}

impl<S> Jabber<S>
where
    S: AsyncRead + AsyncWrite + Unpin,
{
    pub fn new(
        reader: ReadHalf<S>,
        writer: WriteHalf<S>,
        jid: Option<JID>,
        auth: Option<Arc<SASLConfig>>,
        server: String,
    ) -> Self {
        let reader = Reader::new(reader);
        let writer = Writer::new(writer);
        Self {
            reader,
            writer,
            jid,
            auth,
            server,
        }
    }
}

impl<S> Jabber<S>
where
    S: AsyncRead + AsyncWrite + Unpin + Send,
    Jabber<S>: std::fmt::Debug,
{
    // pub async fn negotiate(self) -> Result<Jabber<S>> {}

    #[instrument]
    pub async fn start_stream(&mut self) -> Result<()> {
        // client to server

        // declaration
        self.writer.write_declaration(XML_VERSION).await?;

        // opening stream element
        let server = self.server.clone().try_into()?;
        let stream = Stream::new_client(None, server, None, "en".to_string());
        self.writer.write_start(&stream).await?;

        // server to client

        // may or may not send a declaration
        let decl = self.reader.read_prolog().await?;

        // receive stream element and validate
        let stream: Stream = self.reader.read_start().await?;
        debug!("got stream: {:?}", stream);
        if let Some(from) = stream.from {
            self.server = from.to_string()
        }

        Ok(())
    }

    pub async fn get_features(&mut self) -> Result<Features> {
        debug!("getting features");
        let features: Features = self.reader.read().await?;
        debug!("got features: {:?}", features);
        Ok(features)
    }

    pub fn into_inner(self) -> S {
        self.reader.into_inner().unsplit(self.writer.into_inner())
    }
}

impl Jabber<Unencrypted> {
    pub async fn starttls(mut self) -> Result<Jabber<Tls>> {
        self.writer
            .write_full(&StartTls { required: false })
            .await?;
        let proceed: Proceed = self.reader.read().await?;
        debug!("got proceed: {:?}", proceed);
        let connector = TlsConnector::new().unwrap();
        let stream = self.reader.into_inner().unsplit(self.writer.into_inner());
        if let Ok(tlsstream) = tokio_native_tls::TlsConnector::from(connector)
            .connect(&self.server, stream)
            .await
        {
            let (read, write) = tokio::io::split(tlsstream);
            let client = Jabber::new(
                read,
                write,
                self.jid.to_owned(),
                self.auth.to_owned(),
                self.server.to_owned(),
            );
            return Ok(client);
        } else {
            return Err(Error::Connection);
        }
    }
}

impl std::fmt::Debug for Jabber<Tls> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("Jabber")
            .field("connection", &"tls")
            .field("jid", &self.jid)
            .field("auth", &self.auth)
            .field("server", &self.server)
            .finish()
    }
}

impl std::fmt::Debug for Jabber<Unencrypted> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("Jabber")
            .field("connection", &"unencrypted")
            .field("jid", &self.jid)
            .field("auth", &self.auth)
            .field("server", &self.server)
            .finish()
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::connection::Connection;
    use test_log::test;

    #[test(tokio::test)]
    async fn start_stream() {
        let connection = Connection::connect("blos.sm").await.unwrap();
        match connection {
            Connection::Encrypted(mut c) => c.start_stream().await.unwrap(),
            Connection::Unencrypted(mut c) => c.start_stream().await.unwrap(),
        }
    }
}