videosdk-server-sdk 0.1.0

//! Composition settings and handles shared by every egress: recordings, HLS and
//! RTMP.

use serde::Serialize;
use serde_json::Value;

use crate::common::{
    CompositionConfig, CompositionQuality, LayoutConfig, LayoutPriority, LayoutType, Orientation,
    Theme,
};

/// A composition layout: one of the named layouts, or a custom template.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum CompositionLayout {
    /// An even grid of participants.
    Grid,
    /// Highlights the active participant.
    Spotlight,
    /// A main stage with a sidebar of participants.
    Sidebar,
    /// Renders a custom template, given its URL, instead of a named layout.
    Custom(String),
}

impl CompositionLayout {
    /// A custom-template layout.
    pub fn custom(template_url: impl Into<String>) -> Self {
        CompositionLayout::Custom(template_url.into())
    }

    /// The wire layout type of a named layout, or `None` for a custom template.
    fn layout_type(&self) -> Option<LayoutType> {
        match self {
            CompositionLayout::Grid => Some(LayoutType::Grid),
            CompositionLayout::Spotlight => Some(LayoutType::Spotlight),
            CompositionLayout::Sidebar => Some(LayoutType::Sidebar),
            CompositionLayout::Custom(_) => None,
        }
    }
}

/// The composition options shared by every egress: layout, priority, grid size,
/// orientation, theme and quality.
///
/// If `layout` is omitted while `quality`, `theme` or `orientation` are set, the
/// layout defaults to [`CompositionLayout::Grid`] — the API requires a layout
/// whenever any other composition option is present.
#[derive(Debug, Clone, Default)]
pub struct Composition {
    /// A named layout, or a custom template.
    pub layout: Option<CompositionLayout>,
    /// The speaker priority. HLS and RTMP require it when a layout is present,
    /// so the SDK defaults it to [`LayoutPriority::Speaker`] for those.
    pub priority: Option<LayoutPriority>,
    /// The number of tiles in a grid layout: 0-25, defaulting to 25.
    pub grid_size: Option<u32>,
    /// The composition's orientation.
    pub orientation: Option<Orientation>,
    /// The composition's theme.
    pub theme: Option<Theme>,
    /// The recorder quality tier.
    pub quality: Option<CompositionQuality>,
}

/// The request-body composition settings produced by [`composition_to_config`].
#[derive(Debug, Clone, Default, PartialEq, Eq)]
pub(crate) struct MappedComposition {
    pub(crate) config: Option<CompositionConfig>,
    pub(crate) template_url: Option<String>,
}

/// Converts a [`Composition`] into the request-body composition settings.
///
/// `default_priority` is applied to a named layout that has no explicit
/// priority; HLS and RTMP require a priority whenever a layout is present.
pub(crate) fn composition_to_config(
    composition: Option<&Composition>,
    default_priority: Option<LayoutPriority>,
) -> MappedComposition {
    let Some(composition) = composition else {
        return MappedComposition::default();
    };

    let priority = || composition.priority.or(default_priority);
    let mut config = CompositionConfig::default();
    let mut template_url = None;

    match &composition.layout {
        Some(CompositionLayout::Custom(url)) => template_url = Some(url.clone()),
        Some(named) => {
            config.layout = Some(LayoutConfig {
                kind: named.layout_type(),
                priority: priority(),
                grid_size: composition.grid_size,
            })
        }
        None => {}
    }

    config.orientation = composition.orientation;
    config.theme = composition.theme;
    config.quality = composition.quality;

    // The API rejects (HTTP 406) any non-empty `config` that has no `layout` —
    // even alongside a `templateUrl`. If the caller set quality, theme or
    // orientation without a named layout, default the layout to GRID so the
    // composition starts. With a custom template, the top-level `templateUrl`
    // remains the more specific layout directive downstream.
    if !config.is_empty() && config.layout.is_none() {
        config.layout = Some(LayoutConfig {
            kind: Some(LayoutType::Grid),
            priority: priority(),
            grid_size: None,
        });
    }

    MappedComposition {
        config: (!config.is_empty()).then_some(config),
        template_url,
    }
}

/* -------------------------------- egress handles ------------------------------- */

/// The kind of egress an [`EgressHandle`] refers to.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum EgressType {
    /// A room (composed) recording.
    Recording,
    /// A server-side composed recording.
    Composite,
    /// An HLS stream.
    Hls,
    /// An RTMP-out livestream.
    Livestream,
}

/// A handle to a running egress.
///
/// `start` returns one; pass it — or a bare room id — to `stop`.
///
/// Recordings, HLS and RTMP stop by `room_id`, where `id` is only an optional
/// disambiguator. **Composite** recordings stop by `id` (their `recordingId`),
/// which their start response provides.
#[derive(Debug, Clone)]
pub struct EgressHandle {
    /// Which egress this handle refers to.
    pub kind: EgressType,
    /// The room the egress runs in — the primary stop key.
    pub room_id: String,
    /// The server id, when the start response provides one.
    pub id: Option<String>,
    /// The session correlation id, when the start response provides one.
    pub session_id: Option<String>,
    /// The raw start response: a confirmation string, or an object.
    pub raw: Option<Value>,
}

/// Builds a handle from a start response, which is sometimes a bare confirmation
/// string and sometimes an id-bearing object.
pub(crate) fn to_egress_handle(kind: EgressType, room_id: &str, raw: Value) -> EgressHandle {
    let mut handle = EgressHandle {
        kind,
        room_id: room_id.to_string(),
        id: None,
        session_id: None,
        raw: None,
    };

    if let Some(object) = raw.as_object() {
        let string = |key: &str| object.get(key).and_then(Value::as_str).map(str::to_string);
        handle.id = string("recordingId")
            .or_else(|| string("id"))
            .or_else(|| string("_id"));
        handle.session_id = string("sessionId");
        if let Some(room_id) = string("roomId") {
            handle.room_id = room_id;
        }
    }

    handle.raw = Some(raw);
    handle
}

/// What to stop: an [`EgressHandle`], or a bare room id.
///
/// ```no_run
/// # async fn f(client: &videosdk::Client, handle: videosdk::EgressHandle) -> Result<(), videosdk::Error> {
/// client.hls().stop(&handle).await?;
/// client.hls().stop("abcd-efgh-ijkl").await?;
/// # Ok(())
/// # }
/// ```
#[derive(Debug, Clone)]
pub struct StopTarget {
    /// The room the egress runs in.
    pub room_id: String,
    /// The specific egress to stop, when known.
    pub id: Option<String>,
}

impl From<&str> for StopTarget {
    fn from(room_id: &str) -> Self {
        Self {
            room_id: room_id.to_string(),
            id: None,
        }
    }
}

impl From<String> for StopTarget {
    fn from(room_id: String) -> Self {
        Self { room_id, id: None }
    }
}

impl From<EgressHandle> for StopTarget {
    fn from(handle: EgressHandle) -> Self {
        Self {
            room_id: handle.room_id,
            id: handle.id,
        }
    }
}

impl From<&EgressHandle> for StopTarget {
    fn from(handle: &EgressHandle) -> Self {
        Self {
            room_id: handle.room_id.clone(),
            id: handle.id.clone(),
        }
    }
}

/// The body of a `stop` request: `{roomId, id?}`.
#[derive(Debug, Serialize)]
#[serde(rename_all = "camelCase")]
pub(crate) struct StopWire<'a> {
    room_id: &'a str,
    #[serde(skip_serializing_if = "Option::is_none")]
    id: Option<&'a str>,
}

impl<'a> From<&'a StopTarget> for StopWire<'a> {
    fn from(target: &'a StopTarget) -> Self {
        Self {
            room_id: &target.room_id,
            id: target.id.as_deref().filter(|id| !id.is_empty()),
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use serde_json::json;

    fn config_of(composition: Composition, default: Option<LayoutPriority>) -> Value {
        let mapped = composition_to_config(Some(&composition), default);
        json!({
            "config": mapped.config.map(|c| serde_json::to_value(c).unwrap()),
            "templateUrl": mapped.template_url,
        })
    }

    #[test]
    fn no_composition_maps_to_nothing() {
        assert_eq!(
            composition_to_config(None, None),
            MappedComposition::default()
        );
    }

    #[test]
    fn an_empty_composition_maps_to_nothing() {
        let mapped = composition_to_config(Some(&Composition::default()), None);
        assert_eq!(mapped, MappedComposition::default());
    }

    #[test]
    fn a_named_layout_is_uppercased() {
        let mapped = config_of(
            Composition {
                layout: Some(CompositionLayout::Spotlight),
                ..Default::default()
            },
            None,
        );
        assert_eq!(mapped["config"], json!({"layout": {"type": "SPOTLIGHT"}}));
        assert_eq!(mapped["templateUrl"], json!(null));
    }

    #[test]
    fn a_custom_layout_becomes_a_sibling_template_url_not_a_config_layout() {
        let mapped = config_of(
            Composition {
                layout: Some(CompositionLayout::custom("https://example.com/t.html")),
                ..Default::default()
            },
            None,
        );
        assert_eq!(mapped["config"], json!(null));
        assert_eq!(mapped["templateUrl"], json!("https://example.com/t.html"));
    }

    #[test]
    fn a_default_priority_applies_only_when_none_is_given() {
        let mapped = config_of(
            Composition {
                layout: Some(CompositionLayout::Grid),
                ..Default::default()
            },
            Some(LayoutPriority::Speaker),
        );
        assert_eq!(mapped["config"]["layout"]["priority"], json!("SPEAKER"));

        let mapped = config_of(
            Composition {
                layout: Some(CompositionLayout::Grid),
                priority: Some(LayoutPriority::Pin),
                ..Default::default()
            },
            Some(LayoutPriority::Speaker),
        );
        assert_eq!(mapped["config"]["layout"]["priority"], json!("PIN"));
    }

    #[test]
    fn recordings_send_no_priority_by_default() {
        let mapped = config_of(
            Composition {
                layout: Some(CompositionLayout::Grid),
                ..Default::default()
            },
            None,
        );
        assert_eq!(mapped["config"], json!({"layout": {"type": "GRID"}}));
    }

    #[test]
    fn grid_size_rides_along_with_a_named_layout() {
        let mapped = config_of(
            Composition {
                layout: Some(CompositionLayout::Grid),
                grid_size: Some(9),
                ..Default::default()
            },
            None,
        );
        assert_eq!(
            mapped["config"]["layout"],
            json!({"type": "GRID", "gridSize": 9})
        );
    }

    /// The backend answers 406 to a non-empty `config` with no `layout`.
    #[test]
    fn a_layoutless_config_gets_grid_injected() {
        let mapped = config_of(
            Composition {
                quality: Some(CompositionQuality::High),
                theme: Some(Theme::Dark),
                ..Default::default()
            },
            None,
        );
        assert_eq!(
            mapped["config"],
            json!({"layout": {"type": "GRID"}, "theme": "DARK", "quality": "high"})
        );
    }

    #[test]
    fn grid_injection_carries_the_resolved_priority_but_not_grid_size() {
        let mapped = config_of(
            Composition {
                orientation: Some(Orientation::Portrait),
                grid_size: Some(4),
                ..Default::default()
            },
            Some(LayoutPriority::Speaker),
        );
        assert_eq!(
            mapped["config"]["layout"],
            json!({"type": "GRID", "priority": "SPEAKER"})
        );
    }

    #[test]
    fn a_custom_template_with_other_options_still_gets_grid_injected() {
        let mapped = config_of(
            Composition {
                layout: Some(CompositionLayout::custom("https://example.com/t.html")),
                quality: Some(CompositionQuality::Low),
                ..Default::default()
            },
            None,
        );
        assert_eq!(
            mapped["config"],
            json!({"layout": {"type": "GRID"}, "quality": "low"})
        );
        assert_eq!(mapped["templateUrl"], json!("https://example.com/t.html"));
    }

    /* ------------------------------- handles ------------------------------- */

    #[test]
    fn a_string_start_response_yields_a_room_keyed_handle() {
        let handle = to_egress_handle(EgressType::Hls, "r-1", json!("HLS started"));
        assert_eq!(handle.room_id, "r-1");
        assert!(handle.id.is_none());
        assert_eq!(handle.raw, Some(json!("HLS started")));
    }

    #[test]
    fn an_object_start_response_yields_ids_in_priority_order() {
        let handle = to_egress_handle(
            EgressType::Composite,
            "r-1",
            json!({"recordingId": "rec-1", "id": "other", "_id": "another", "sessionId": "s-1"}),
        );
        assert_eq!(handle.id.as_deref(), Some("rec-1"));
        assert_eq!(handle.session_id.as_deref(), Some("s-1"));

        let handle = to_egress_handle(EgressType::Hls, "r-1", json!({"id": "h-1"}));
        assert_eq!(handle.id.as_deref(), Some("h-1"));

        let handle = to_egress_handle(EgressType::Hls, "r-1", json!({"_id": "h-2"}));
        assert_eq!(handle.id.as_deref(), Some("h-2"));
    }

    #[test]
    fn a_start_response_room_id_overrides_the_requested_one() {
        let handle = to_egress_handle(
            EgressType::Recording,
            "requested",
            json!({"roomId": "real"}),
        );
        assert_eq!(handle.room_id, "real");
    }

    #[test]
    fn stop_targets_accept_handles_and_bare_room_ids() {
        let handle = to_egress_handle(EgressType::Recording, "r-1", json!({"id": "e-1"}));
        let target: StopTarget = (&handle).into();
        assert_eq!(target.room_id, "r-1");
        assert_eq!(target.id.as_deref(), Some("e-1"));

        let target: StopTarget = "r-2".into();
        assert_eq!(target.room_id, "r-2");
        assert!(target.id.is_none());
    }

    #[test]
    fn stop_wire_omits_an_absent_or_empty_id() {
        let target = StopTarget {
            room_id: "r-1".into(),
            id: None,
        };
        assert_eq!(
            serde_json::to_value(StopWire::from(&target)).unwrap(),
            json!({"roomId": "r-1"})
        );

        let target = StopTarget {
            room_id: "r-1".into(),
            id: Some(String::new()),
        };
        assert_eq!(
            serde_json::to_value(StopWire::from(&target)).unwrap(),
            json!({"roomId": "r-1"})
        );

        let target = StopTarget {
            room_id: "r-1".into(),
            id: Some("e-1".into()),
        };
        assert_eq!(
            serde_json::to_value(StopWire::from(&target)).unwrap(),
            json!({"roomId": "r-1", "id": "e-1"})
        );
    }
}