// Copyright (c) 2024 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::{AsXml, FromXml};

use crate::ns;
use std::num::NonZeroU32;

/// Advertises limits on this stream.
#[derive(FromXml, AsXml, Debug, Clone, PartialEq)]
#[xml(namespace = ns::STREAM_LIMITS, name = "limits")]
pub struct Limits {
    /// Maximum size of any first-level stream elements (including stanzas), in bytes the
    /// announcing entity is willing to accept.
    // TODO: Replace that with a direct u32 once xso supports that.
    #[xml(child(default))]
    pub max_bytes: Option<MaxBytes>,

    /// Number of seconds without any traffic from the iniating entity after which the server may
    /// consider the stream idle, and either perform liveness checks or terminate the stream.
    // TODO: Replace that with a direct u32 once xso supports that.
    #[xml(child(default))]
    pub idle_seconds: Option<IdleSeconds>,
}

/// Maximum size of any first-level stream elements (including stanzas), in bytes the
/// announcing entity is willing to accept.
#[derive(FromXml, AsXml, Debug, Clone, PartialEq)]
#[xml(namespace = ns::STREAM_LIMITS, name = "max-bytes")]
pub struct MaxBytes {
    /// The number of bytes.
    #[xml(text)]
    pub value: NonZeroU32,
}

/// Number of seconds without any traffic from the iniating entity after which the server may
/// consider the stream idle, and either perform liveness checks or terminate the stream.
#[derive(FromXml, AsXml, Debug, Clone, PartialEq)]
#[xml(namespace = ns::STREAM_LIMITS, name = "idle-seconds")]
pub struct IdleSeconds {
    /// The number of seconds.
    #[xml(text)]
    pub value: NonZeroU32,
}

#[cfg(test)]
mod tests {
    use super::*;
    use minidom::Element;

    #[test]
    fn test_size() {
        assert_size!(Limits, 8);
        assert_size!(MaxBytes, 4);
        assert_size!(IdleSeconds, 4);
    }

    #[test]
    fn test_simple() {
        let elem: Element =
            "<limits xmlns='urn:xmpp:stream-limits:0'><max-bytes>262144</max-bytes></limits>"
                .parse()
                .unwrap();
        let limits = Limits::try_from(elem).unwrap();
        assert_eq!(
            limits.max_bytes.unwrap().value,
            NonZeroU32::new(262144).unwrap()
        );
        assert!(limits.idle_seconds.is_none());
    }
}