//! `POST /_matrix/federation/*/get_missing_events/{roomId}`
//!
//! Retrieves previous events that the sender is missing.

pub mod v1 {
    //! `/v1/` ([spec])
    //!
    //! [spec]: https://spec.matrix.org/v1.2/server-server-api/#post_matrixfederationv1get_missing_eventsroomid

    use js_int::{uint, UInt};
    use ruma_common::{api::ruma_api, OwnedEventId, RoomId};
    use serde_json::value::RawValue as RawJsonValue;

    ruma_api! {
        metadata: {
            description: "Retrieves previous events that the sender is missing.",
            method: POST,
            name: "get_missing_events",
            stable_path: "/_matrix/federation/v1/get_missing_events/:room_id",
            rate_limited: false,
            authentication: ServerSignatures,
            added: 1.0,
        }

        request: {
            /// The room ID to search in.
            #[ruma_api(path)]
            pub room_id: &'a RoomId,

            /// The maximum number of events to retrieve.
            ///
            /// Defaults to 10.
            #[serde(default = "default_limit", skip_serializing_if = "is_default_limit")]
            pub limit: UInt,

            /// The minimum depth of events to retrieve.
            ///
            /// Defaults to 0.
            #[serde(default, skip_serializing_if = "ruma_common::serde::is_default")]
            pub min_depth: UInt,

            /// The latest event IDs that the sender already has.
            ///
            /// These are skipped when retrieving the previous events of `latest_events`.
            pub earliest_events: &'a [OwnedEventId],

            /// The event IDs to retrieve the previous events for.
            pub latest_events: &'a [OwnedEventId],
        }

        #[derive(Default)]
        response: {
            /// The missing PDUs.
            pub events: Vec<Box<RawJsonValue>>,
        }
    }

    impl<'a> Request<'a> {
        /// Creates a new `Request` for events in the given room with the given constraints.
        pub fn new(
            room_id: &'a RoomId,
            earliest_events: &'a [OwnedEventId],
            latest_events: &'a [OwnedEventId],
        ) -> Self {
            Self {
                room_id,
                limit: default_limit(),
                min_depth: UInt::default(),
                earliest_events,
                latest_events,
            }
        }
    }

    impl Response {
        /// Creates a new `Response` with the given events.
        pub fn new(events: Vec<Box<RawJsonValue>>) -> Self {
            Self { events }
        }
    }

    fn default_limit() -> UInt {
        uint!(10)
    }

    fn is_default_limit(val: &UInt) -> bool {
        *val == default_limit()
    }
}