//! [GET /_matrix/client/r0/rooms/{roomId}/joined_members](https://matrix.org/docs/spec/client_server/r0.6.1#get-matrix-client-r0-rooms-roomid-joined-members)

use std::collections::BTreeMap;

use ruma_api::ruma_api;
use ruma_identifiers::{MxcUri, RoomId, UserId};
use serde::{Deserialize, Serialize};

ruma_api! {
    metadata: {
        description: "Get a map of user ids to member info objects for members of the room. Primarily for use in Application Services.",
        method: GET,
        name: "joined_members",
        path: "/_matrix/client/r0/rooms/:room_id/joined_members",
        rate_limited: false,
        authentication: AccessToken,
    }

    request: {
        /// The room to get the members of.
        #[ruma_api(path)]
        pub room_id: &'a RoomId,
    }

    response: {
        /// A list of the rooms the user is in, i.e.
        /// the ID of each room in which the user has joined membership.
        pub joined: BTreeMap<Box<UserId>, RoomMember>,
    }

    error: crate::Error
}

impl<'a> Request<'a> {
    /// Creates a new `Request` with the given room ID.
    pub fn new(room_id: &'a RoomId) -> Self {
        Self { room_id }
    }
}

impl Response {
    /// Creates a new `Response` with the given joined rooms.
    pub fn new(joined: BTreeMap<Box<UserId>, RoomMember>) -> Self {
        Self { joined }
    }
}

/// Information about a room member.
#[derive(Clone, Debug, Default, Deserialize, Serialize)]
#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
pub struct RoomMember {
    /// The display name of the user.
    #[serde(skip_serializing_if = "Option::is_none")]
    pub display_name: Option<String>,

    /// The mxc avatar url of the user.
    ///
    /// If you activate the `compat` feature, this field being an empty string in JSON will result
    /// in `None` here during deserialization.
    #[serde(skip_serializing_if = "Option::is_none")]
    #[cfg_attr(
        feature = "compat",
        serde(default, deserialize_with = "ruma_serde::empty_string_as_none")
    )]
    pub avatar_url: Option<Box<MxcUri>>,
}

impl RoomMember {
    /// Creates an empty `RoomMember`.
    pub fn new() -> Self {
        Default::default()
    }
}

#[cfg(test)]
mod test {
    use super::RoomMember;
    use matches::assert_matches;
    use serde_json::{from_value as from_json_value, json};

    #[test]
    fn deserialize_room_member() {
        assert_matches!(
            from_json_value::<RoomMember>(json!({
                "display_name": "alice",
                "avatar_url": "mxc://localhost/wefuiwegh8742w",
            })).unwrap(),
            RoomMember {
                display_name: Some(display_name),
                avatar_url: Some(avatar_url),
            } if display_name == "alice"
                && avatar_url == "mxc://localhost/wefuiwegh8742w"
        );

        #[cfg(feature = "compat")]
        assert_matches!(
            from_json_value::<RoomMember>(json!({
                "display_name": "alice",
                "avatar_url": "",
            })).unwrap(),
            RoomMember {
                display_name: Some(display_name),
                avatar_url: None,
            } if display_name == "alice"
        );
    }
}