// Copyright (c) 2017 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

use xso::{FromXml, IntoXml};

use crate::iq::IqSetPayload;
use crate::ns;
use crate::util::text_node_codecs::{Base64, Codec};

generate_id!(
    /// An identifier matching a stream.
    StreamId
);

generate_attribute!(
/// Which stanza type to use to exchange data.
Stanza, "stanza", {
    /// `<iq/>` gives a feedback on whether the chunk has been received or not,
    /// which is useful in the case the recipient might not receive them in a
    /// timely manner, or to do your own throttling based on the results.
    Iq => "iq",

    /// `<message/>` can be faster, since it doesn’t require any feedback, but in
    /// practice it will be throttled by the servers on the way.
    Message => "message",
}, Default = Iq);

generate_element!(
/// Starts an In-Band Bytestream session with the given parameters.
Open, "open", IBB,
attributes: [
    /// Maximum size in bytes for each chunk.
    block_size: Required<u16> = "block-size",

    /// The identifier to be used to create a stream.
    sid: Required<StreamId> = "sid",

    /// Which stanza type to use to exchange data.
    stanza: Default<Stanza> = "stanza",
]);

impl IqSetPayload for Open {}

generate_element!(
/// Exchange a chunk of data in an open stream.
Data, "data", IBB,
    attributes: [
        /// Sequence number of this chunk, must wraparound after 65535.
        seq: Required<u16> = "seq",

        /// The identifier of the stream on which data is being exchanged.
        sid: Required<StreamId> = "sid"
    ],
    text: (
        /// Vector of bytes to be exchanged.
        data: Base64
    )
);

impl IqSetPayload for Data {}

/// Close an open stream.
#[derive(FromXml, IntoXml, PartialEq, Debug, Clone)]
#[xml(namespace = ns::IBB, name = "close")]
pub struct Close {
    /// The identifier of the stream to be closed.
    #[xml(attribute)]
    pub sid: StreamId,
}

impl IqSetPayload for Close {}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::Element;
    use xso::error::{Error, FromElementError};

    #[cfg(target_pointer_width = "32")]
    #[test]
    fn test_size() {
        assert_size!(StreamId, 12);
        assert_size!(Stanza, 1);
        assert_size!(Open, 16);
        assert_size!(Data, 28);
        assert_size!(Close, 12);
    }

    #[cfg(target_pointer_width = "64")]
    #[test]
    fn test_size() {
        assert_size!(StreamId, 24);
        assert_size!(Stanza, 1);
        assert_size!(Open, 32);
        assert_size!(Data, 56);
        assert_size!(Close, 24);
    }

    #[test]
    fn test_simple() {
        let sid = StreamId(String::from("coucou"));

        let elem: Element =
            "<open xmlns='http://jabber.org/protocol/ibb' block-size='3' sid='coucou'/>"
                .parse()
                .unwrap();
        let open = Open::try_from(elem).unwrap();
        assert_eq!(open.block_size, 3);
        assert_eq!(open.sid, sid);
        assert_eq!(open.stanza, Stanza::Iq);

        let elem: Element =
            "<data xmlns='http://jabber.org/protocol/ibb' seq='0' sid='coucou'>AAAA</data>"
                .parse()
                .unwrap();
        let data = Data::try_from(elem).unwrap();
        assert_eq!(data.seq, 0);
        assert_eq!(data.sid, sid);
        assert_eq!(data.data, vec!(0, 0, 0));

        let elem: Element = "<close xmlns='http://jabber.org/protocol/ibb' sid='coucou'/>"
            .parse()
            .unwrap();
        let close = Close::try_from(elem).unwrap();
        assert_eq!(close.sid, sid);
    }

    #[test]
    fn test_invalid() {
        let elem: Element = "<open xmlns='http://jabber.org/protocol/ibb'/>"
            .parse()
            .unwrap();
        let error = Open::try_from(elem).unwrap_err();
        let message = match error {
            FromElementError::Invalid(Error::Other(string)) => string,
            _ => panic!(),
        };
        assert_eq!(message, "Required attribute 'block-size' missing.");

        let elem: Element = "<open xmlns='http://jabber.org/protocol/ibb' block-size='-5'/>"
            .parse()
            .unwrap();
        let error = Open::try_from(elem).unwrap_err();
        let message = match error {
            FromElementError::Invalid(Error::TextParseError(error))
                if error.is::<std::num::ParseIntError>() =>
            {
                error
            }
            _ => panic!(),
        };
        assert_eq!(message.to_string(), "invalid digit found in string");

        let elem: Element = "<open xmlns='http://jabber.org/protocol/ibb' block-size='128'/>"
            .parse()
            .unwrap();
        let error = Open::try_from(elem).unwrap_err();
        let message = match error {
            FromElementError::Invalid(Error::Other(error)) => error,
            _ => panic!(),
        };
        assert_eq!(message, "Required attribute 'sid' missing.");
    }

    #[test]
    fn test_invalid_stanza() {
        let elem: Element = "<open xmlns='http://jabber.org/protocol/ibb' block-size='128' sid='coucou' stanza='fdsq'/>".parse().unwrap();
        let error = Open::try_from(elem).unwrap_err();
        let message = match error {
            FromElementError::Invalid(Error::TextParseError(string)) => string,
            _ => panic!(),
        };
        assert_eq!(message.to_string(), "Unknown value for 'stanza' attribute.");
    }
}