//! [POST /_matrix/identity/v2/store-invite](https://matrix.org/docs/spec/identity_service/r0.3.0#post-matrix-identity-v2-store-invite)

use ruma_api::ruma_api;
use ruma_common::thirdparty::Medium;
use ruma_identifiers::{MxcUri, RoomAliasId, RoomId, UserId};
use serde::{ser::SerializeSeq, Deserialize, Serialize};

ruma_api! {
    metadata: {
        description: "Store pending invitations to a user's 3PID.",
        method: POST,
        name: "store_invitation",
        path: "/_matrix/identity/v2/store-invite",
        authentication: AccessToken,
        rate_limited: false,
    }

    request: {
        /// The type of the third party identifier for the invited user.
        ///
        /// Currently, only `Medium::Email` is supported.
        pub medium: &'a Medium,

        /// The email address of the invited user.
        pub address: &'a str,

        /// The Matrix room ID to which the user is invited.
        pub room_id: &'a RoomId,

        /// The Matrix user ID of the inviting user.
        pub sender: &'a UserId,

        /// The Matrix room alias for the room to which the user is invited.
        ///
        /// This should be retrieved from the `m.room.canonical` state event.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub room_alias: Option<&'a RoomAliasId>,

        /// The Content URI for the room to which the user is invited.
        ///
        /// This should be retrieved from the `m.room.avatar` state event.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub room_avatar_url: Option<&'a MxcUri>,

        /// The `join_rule` for the room to which the user is invited.
        ///
        /// This should be retrieved from the `m.room.join_rules` state event.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub room_join_rules: Option<&'a str>,

        /// The name of the room to which the user is invited.
        ///
        /// This should be retrieved from the `m.room.name` state event.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub room_name: Option<&'a str>,

        /// The display name of the user ID initiating the invite.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub sender_display_name: Option<&'a str>,

        /// The Content URI for the avater of the user ID initiating the invite.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub sender_avatar_url: Option<&'a MxcUri>,
    }

    response: {
        /// The generated token. Must be a string consisting of the characters `[0-9a-zA-Z.=_-]`.
        ///
        /// Its length must not exceed 255 characters and it must not be empty.
        pub token: String,

        /// A list of [server's long-term public key, generated ephemeral public key].
        pub public_keys: PublicKeys,

        /// The generated (redacted) display_name. An example is `f...@b...`.
        pub display_name: String,
    }
}

impl<'a> Request<'a> {
    /// Creates a new `Request with the given medium, email address, room ID and sender.
    pub fn new(
        medium: &'a Medium,
        address: &'a str,
        room_id: &'a RoomId,
        sender: &'a UserId,
    ) -> Self {
        Self {
            medium,
            address,
            room_id,
            sender,
            room_alias: None,
            room_avatar_url: None,
            room_join_rules: None,
            room_name: None,
            sender_display_name: None,
            sender_avatar_url: None,
        }
    }

    /// Creates a new `Request` with the given email address, room ID and sender.
    pub fn email(address: &'a str, room_id: &'a RoomId, sender: &'a UserId) -> Self {
        Self::new(&Medium::Email, address, room_id, sender)
    }
}

impl Response {
    /// Creates a new `Response` with the given token, public keys and display name.
    pub fn new(token: String, public_keys: PublicKeys, display_name: String) -> Self {
        Self { token, public_keys, display_name }
    }
}

/// The server's long-term public key and generated ephemeral public key.
#[derive(Debug, Clone)]
#[allow(clippy::exhaustive_structs)]
pub struct PublicKeys {
    /// The server's long-term public key.
    pub server_key: String,

    /// The generated ephemeral public key.
    pub ephemeral_key: String,
}

impl<'de> Deserialize<'de> for PublicKeys {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::Deserializer<'de>,
    {
        let [server_key, ephemeral_key] = <[String; 2]>::deserialize(deserializer)?;

        Ok(Self { server_key, ephemeral_key })
    }
}

impl Serialize for PublicKeys {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: serde::Serializer,
    {
        let mut seq = serializer.serialize_seq(Some(2))?;

        seq.serialize_element(&self.server_key)?;
        seq.serialize_element(&self.ephemeral_key)?;

        seq.end()
    }
}