//! Server Requests
//!
//! These are requests that a `cogo_http::Server` receives, and include its method,
//! target URI, headers, and message body.
use std::io::{self, Read};
use std::net::SocketAddr;
use std::time::Duration;

use crate::buffer::BufReader;
use crate::net::NetworkStream;
use crate::version::{HttpVersion};
use crate::method::Method;
use crate::header::{Headers, ContentLength, TransferEncoding};
use crate::http::h1::{self, Incoming, HttpReader};
use crate::http::h1::HttpReader::{SizedReader, ChunkedReader, EmptyReader};
use crate::uri::RequestUri;

/// A request bundles several parts of an incoming `NetworkStream`, given to a `Handler`.
pub struct Request<'a, 'b: 'a> {
    /// The IP address of the remote connection.
    pub remote_addr: SocketAddr,
    /// The `Method`, such as `Get`, `Post`, etc.
    pub method: Method,
    /// The headers of the incoming request.
    pub headers: Headers,
    /// The target request-uri for this request.
    pub uri: RequestUri,
    /// The version of HTTP for this request.
    pub version: HttpVersion,
    pub body: HttpReader<&'a mut BufReader<&'b mut dyn NetworkStream>>
}


impl<'a, 'b: 'a> Request<'a, 'b> {
    /// Create a new Request, reading the StartLine and Headers so they are
    /// immediately useful.
    pub fn new(stream: &'a mut BufReader<&'b mut dyn NetworkStream>, addr: SocketAddr)
        -> crate::Result<Request<'a, 'b>> {

        let Incoming { version, subject: (method, uri), headers } = r#try!(h1::parse_request(stream));
        debug!("Request Line: {:?} {:?} {:?}", method, uri, version);
        debug!("{:?}", headers);

        let body = if headers.has::<ContentLength>() {
            match headers.get::<ContentLength>() {
                Some(&ContentLength(len)) => SizedReader(stream, len),
                None => unreachable!()
            }
        } else if headers.has::<TransferEncoding>() {
            todo!("check for Transfer-Encoding: chunked");
            ChunkedReader(stream, None)
        } else {
            EmptyReader(stream)
        };

        Ok(Request {
            remote_addr: addr,
            method: method,
            uri: uri,
            headers: headers,
            version: version,
            body: body
        })
    }

    /// Set the read timeout of the underlying NetworkStream.
    #[inline]
    pub fn set_read_timeout(&self, timeout: Option<Duration>) -> io::Result<()> {
        self.body.get_ref().get_ref().set_read_timeout(timeout)
    }

    /// Get a reference to the underlying `NetworkStream`.
    #[inline]
    pub fn downcast_ref<T: NetworkStream>(&self) -> Option<&T> {
        self.body.get_ref().get_ref().downcast_ref()
    }

    /// Get a reference to the underlying Ssl stream, if connected
    /// over HTTPS.
    ///
    /// This is actually just an alias for `downcast_ref`.
    #[inline]
    pub fn ssl<T: NetworkStream>(&self) -> Option<&T> {
        self.downcast_ref()
    }

    /// Deconstruct a Request into its constituent parts.
    #[inline]
    pub fn deconstruct(self) -> (SocketAddr, Method, Headers,
                                 RequestUri, HttpVersion,
                                 HttpReader<&'a mut BufReader<&'b mut dyn NetworkStream>>) {
        (self.remote_addr, self.method, self.headers,
         self.uri, self.version, self.body)
    }
}

impl<'a, 'b> Read for Request<'a, 'b> {
    #[inline]
    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
        self.body.read(buf)
    }
}

#[cfg(test)]
mod tests {
    use crate::buffer::BufReader;
    use crate::header::{Host, TransferEncoding, Encoding};
    use crate::net::NetworkStream;
    use crate::mock::MockStream;
    use super::Request;

    use std::io::{self, Read};
    use std::net::SocketAddr;

    fn sock(s: &str) -> SocketAddr {
        s.parse().unwrap()
    }

    fn read_to_string(mut req: Request) -> io::Result<String> {
        let mut s = String::new();
        r#try!(req.read_to_string(&mut s));
        Ok(s)
    }

    #[test]
    fn test_get_empty_body() {
        let mut mock = MockStream::with_input(b"\
            GET / HTTP/1.1\r\n\
            Host: example.domain\r\n\
            \r\n\
            I'm a bad request.\r\n\
        ");

        // FIXME: Use Type ascription
        let mock: &mut dyn NetworkStream = &mut mock;
        let mut stream = BufReader::new(mock);

        let req = Request::new(&mut stream, sock("127.0.0.1:80")).unwrap();
        assert_eq!(read_to_string(req).unwrap(), "".to_owned());
    }

    #[test]
    fn test_get_with_body() {
        let mut mock = MockStream::with_input(b"\
            GET / HTTP/1.1\r\n\
            Host: example.domain\r\n\
            Content-Length: 19\r\n\
            \r\n\
            I'm a good request.\r\n\
        ");

        // FIXME: Use Type ascription
        let mock: &mut dyn NetworkStream = &mut mock;
        let mut stream = BufReader::new(mock);

        let req = Request::new(&mut stream, sock("127.0.0.1:80")).unwrap();
        assert_eq!(read_to_string(req).unwrap(), "I'm a good request.".to_owned());
    }

    #[test]
    fn test_head_empty_body() {
        let mut mock = MockStream::with_input(b"\
            HEAD / HTTP/1.1\r\n\
            Host: example.domain\r\n\
            \r\n\
            I'm a bad request.\r\n\
        ");

        // FIXME: Use Type ascription
        let mock: &mut dyn NetworkStream = &mut mock;
        let mut stream = BufReader::new(mock);

        let req = Request::new(&mut stream, sock("127.0.0.1:80")).unwrap();
        assert_eq!(read_to_string(req).unwrap(), "".to_owned());
    }

    #[test]
    fn test_post_empty_body() {
        let mut mock = MockStream::with_input(b"\
            POST / HTTP/1.1\r\n\
            Host: example.domain\r\n\
            \r\n\
            I'm a bad request.\r\n\
        ");

        // FIXME: Use Type ascription
        let mock: &mut dyn NetworkStream = &mut mock;
        let mut stream = BufReader::new(mock);

        let req = Request::new(&mut stream, sock("127.0.0.1:80")).unwrap();
        assert_eq!(read_to_string(req).unwrap(), "".to_owned());
    }

    #[test]
    fn test_parse_chunked_request() {
        let mut mock = MockStream::with_input(b"\
            POST / HTTP/1.1\r\n\
            Host: example.domain\r\n\
            Transfer-Encoding: chunked\r\n\
            \r\n\
            1\r\n\
            q\r\n\
            2\r\n\
            we\r\n\
            2\r\n\
            rt\r\n\
            0\r\n\
            \r\n"
        );

        // FIXME: Use Type ascription
        let mock: &mut dyn NetworkStream = &mut mock;
        let mut stream = BufReader::new(mock);

        let req = Request::new(&mut stream, sock("127.0.0.1:80")).unwrap();

        // The headers are correct?
        match req.headers.get::<Host>() {
            Some(host) => {
                assert_eq!("example.domain", host.hostname);
            },
            None => panic!("Host header expected!"),
        };
        match req.headers.get::<TransferEncoding>() {
            Some(encodings) => {
                assert_eq!(1, encodings.len());
                assert_eq!(Encoding::Chunked, encodings[0]);
            }
            None => panic!("Transfer-Encoding: chunked expected!"),
        };
        // The content is correctly read?
        assert_eq!(read_to_string(req).unwrap(), "qwert".to_owned());
    }

    /// Tests that when a chunk size is not a valid radix-16 number, an error
    /// is returned.
    #[test]
    fn test_invalid_chunk_size_not_hex_digit() {
        let mut mock = MockStream::with_input(b"\
            POST / HTTP/1.1\r\n\
            Host: example.domain\r\n\
            Transfer-Encoding: chunked\r\n\
            \r\n\
            X\r\n\
            1\r\n\
            0\r\n\
            \r\n"
        );

        // FIXME: Use Type ascription
        let mock: &mut dyn NetworkStream = &mut mock;
        let mut stream = BufReader::new(mock);

        let req = Request::new(&mut stream, sock("127.0.0.1:80")).unwrap();

        assert!(read_to_string(req).is_err());
    }

    /// Tests that when a chunk size contains an invalid extension, an error is
    /// returned.
    #[test]
    fn test_invalid_chunk_size_extension() {
        let mut mock = MockStream::with_input(b"\
            POST / HTTP/1.1\r\n\
            Host: example.domain\r\n\
            Transfer-Encoding: chunked\r\n\
            \r\n\
            1 this is an invalid extension\r\n\
            1\r\n\
            0\r\n\
            \r\n"
        );

        // FIXME: Use Type ascription
        let mock: &mut dyn NetworkStream = &mut mock;
        let mut stream = BufReader::new(mock);

        let req = Request::new(&mut stream, sock("127.0.0.1:80")).unwrap();

        assert!(read_to_string(req).is_err());
    }

    /// Tests that when a valid extension that contains a digit is appended to
    /// the chunk size, the chunk is correctly read.
    #[test]
    fn test_chunk_size_with_extension() {
        let mut mock = MockStream::with_input(b"\
            POST / HTTP/1.1\r\n\
            Host: example.domain\r\n\
            Transfer-Encoding: chunked\r\n\
            \r\n\
            1;this is an extension with a digit 1\r\n\
            1\r\n\
            0\r\n\
            \r\n"
        );

        // FIXME: Use Type ascription
        let mock: &mut dyn NetworkStream = &mut mock;
        let mut stream = BufReader::new(mock);

        let req = Request::new(&mut stream, sock("127.0.0.1:80")).unwrap();

        assert_eq!(read_to_string(req).unwrap(), "1".to_owned());
    }

}
