//! `POST /_matrix/client/*/search`

pub mod v3 {
    //! `/v3/` ([spec])
    //!
    //! [spec]: https://spec.matrix.org/v1.2/client-server-api/#post_matrixclientv3search

    use std::collections::BTreeMap;

    use js_int::{uint, UInt};
    use ruma_common::{
        api::ruma_api,
        events::{AnyRoomEvent, AnyStateEvent},
        serde::{Outgoing, Raw, StringEnum},
        EventId, MxcUri, RoomId, UserId,
    };
    use serde::{Deserialize, Serialize};

    use crate::{
        filter::{IncomingRoomEventFilter, RoomEventFilter},
        PrivOwnedStr,
    };

    ruma_api! {
        metadata: {
            description: "Search events.",
            method: POST,
            name: "search",
            r0_path: "/_matrix/client/r0/search",
            stable_path: "/_matrix/client/v3/search",
            rate_limited: true,
            authentication: AccessToken,
            added: 1.0,
        }

        request: {
            /// The point to return events from.
            ///
            /// If given, this should be a `next_batch` result from a previous call to this endpoint.
            #[ruma_api(query)]
            pub next_batch: Option<&'a str>,

            /// Describes which categories to search in and their criteria.
            pub search_categories: Categories<'a>,
        }

        response: {
            /// A grouping of search results by category.
            pub search_categories: ResultCategories,
        }

        error: crate::Error
    }

    impl<'a> Request<'a> {
        /// Creates a new `Request` with the given categories.
        pub fn new(search_categories: Categories<'a>) -> Self {
            Self { next_batch: None, search_categories }
        }
    }

    impl Response {
        /// Creates a new `Response` with the given search results.
        pub fn new(search_categories: ResultCategories) -> Self {
            Self { search_categories }
        }
    }

    /// Categories of events that can be searched for.
    #[derive(Clone, Debug, Default, Outgoing, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct Categories<'a> {
        /// Criteria for searching room events.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub room_events: Option<Criteria<'a>>,
    }

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

    /// Criteria for searching a category of events.
    #[derive(Clone, Debug, Outgoing, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct Criteria<'a> {
        /// The string to search events for.
        pub search_term: &'a str,

        /// The keys to search for.
        ///
        /// Defaults to all keys.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub keys: Option<&'a [SearchKeys]>,

        /// A `Filter` to apply to the search.
        #[serde(skip_serializing_if = "RoomEventFilter::is_empty")]
        pub filter: RoomEventFilter<'a>,

        /// The order in which to search for results.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub order_by: Option<OrderBy>,

        /// Configures whether any context for the events returned are included in the response.
        #[serde(default, skip_serializing_if = "EventContext::is_default")]
        pub event_context: EventContext,

        /// Requests the server return the current state for each room returned.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub include_state: Option<bool>,

        /// Requests that the server partitions the result set based on the provided list of keys.
        #[serde(default, skip_serializing_if = "Groupings::is_empty")]
        pub groupings: Groupings<'a>,
    }

    impl<'a> Criteria<'a> {
        /// Creates a new `Criteria` with the given search term.
        pub fn new(search_term: &'a str) -> Self {
            Self {
                search_term,
                keys: None,
                filter: RoomEventFilter::default(),
                order_by: None,
                event_context: Default::default(),
                include_state: None,
                groupings: Default::default(),
            }
        }
    }

    /// Configures whether any context for the events returned are included in the response.
    #[derive(Clone, Debug, Deserialize, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct EventContext {
        /// How many events before the result are returned.
        #[serde(
            default = "default_event_context_limit",
            skip_serializing_if = "is_default_event_context_limit"
        )]
        pub before_limit: UInt,

        /// How many events after the result are returned.
        #[serde(
            default = "default_event_context_limit",
            skip_serializing_if = "is_default_event_context_limit"
        )]
        pub after_limit: UInt,

        /// Requests that the server returns the historic profile information for the users that
        /// sent the events that were returned.
        #[serde(default, skip_serializing_if = "ruma_common::serde::is_default")]
        pub include_profile: bool,
    }

    fn default_event_context_limit() -> UInt {
        uint!(5)
    }

    #[allow(clippy::trivially_copy_pass_by_ref)]
    fn is_default_event_context_limit(val: &UInt) -> bool {
        *val == default_event_context_limit()
    }

    impl EventContext {
        /// Creates an `EventContext` with all-default values.
        pub fn new() -> Self {
            Self {
                before_limit: default_event_context_limit(),
                after_limit: default_event_context_limit(),
                include_profile: false,
            }
        }

        /// Returns whether all fields have their default value.
        pub fn is_default(&self) -> bool {
            self.before_limit == default_event_context_limit()
                && self.after_limit == default_event_context_limit()
                && !self.include_profile
        }
    }

    impl Default for EventContext {
        fn default() -> Self {
            Self::new()
        }
    }

    /// Context for search results, if requested.
    #[derive(Clone, Debug, Default, Deserialize, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct EventContextResult {
        /// Pagination token for the end of the chunk.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub end: Option<String>,

        /// Events just after the result.
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub events_after: Vec<Raw<AnyRoomEvent>>,

        /// Events just before the result.
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub events_before: Vec<Raw<AnyRoomEvent>>,

        /// The historic profile information of the users that sent the events returned.
        #[serde(default, skip_serializing_if = "BTreeMap::is_empty")]
        pub profile_info: BTreeMap<Box<UserId>, UserProfile>,

        /// Pagination token for the start of the chunk.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub start: Option<String>,
    }

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

        /// Returns whether all fields are `None` or an empty list.
        pub fn is_empty(&self) -> bool {
            self.end.is_none()
                && self.events_after.is_empty()
                && self.events_before.is_empty()
                && self.profile_info.is_empty()
                && self.start.is_none()
        }
    }

    /// A grouping for partitioning the result set.
    #[derive(Clone, Default, Debug, Deserialize, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct Grouping {
        /// The key within events to use for this grouping.
        pub key: Option<GroupingKey>,
    }

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

        /// Returns whether `key` is `None`.
        pub fn is_empty(&self) -> bool {
            self.key.is_none()
        }
    }

    /// The key within events to use for this grouping.
    ///
    /// This type can hold an arbitrary string. To check for formats that are not available as a
    /// documented variant here, use its string representation, obtained through `.as_str()`.
    #[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, StringEnum)]
    #[ruma_enum(rename_all = "snake_case")]
    #[non_exhaustive]
    pub enum GroupingKey {
        /// `room_id`
        RoomId,

        /// `sender`
        Sender,

        #[doc(hidden)]
        _Custom(PrivOwnedStr),
    }

    impl GroupingKey {
        /// Creates a string slice from this `GroupingKey`.
        pub fn as_str(&self) -> &str {
            self.as_ref()
        }
    }

    /// Requests that the server partitions the result set based on the provided list of keys.
    #[derive(Clone, Default, Debug, Outgoing, Serialize)]
    #[incoming_derive(Default)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct Groupings<'a> {
        /// List of groups to request.
        #[serde(default, skip_serializing_if = "<[_]>::is_empty")]
        pub group_by: &'a [Grouping],
    }

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

        /// Returns `true` if all fields are empty.
        pub fn is_empty(&self) -> bool {
            self.group_by.is_empty()
        }
    }

    /// The keys to search for.
    ///
    /// This type can hold an arbitrary string. To check for formats that are not available as a
    /// documented variant here, use its string representation, obtained through `.as_str()`.
    #[derive(Clone, Debug, PartialEq, Eq, StringEnum)]
    #[non_exhaustive]
    pub enum SearchKeys {
        /// content.body
        #[ruma_enum(rename = "content.body")]
        ContentBody,

        /// content.name
        #[ruma_enum(rename = "content.name")]
        ContentName,

        /// content.topic
        #[ruma_enum(rename = "content.topic")]
        ContentTopic,

        #[doc(hidden)]
        _Custom(PrivOwnedStr),
    }

    impl SearchKeys {
        /// Creates a string slice from this `SearchKeys`.
        pub fn as_str(&self) -> &str {
            self.as_ref()
        }
    }

    /// The order in which to search for results.
    #[derive(Clone, Debug, PartialEq, Eq, StringEnum)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    #[ruma_enum(rename_all = "snake_case")]
    pub enum OrderBy {
        /// Prioritize recent events.
        Recent,

        /// Prioritize events by a numerical ranking of how closely they matched the search
        /// criteria.
        Rank,

        #[doc(hidden)]
        _Custom(PrivOwnedStr),
    }

    /// Categories of events that can be searched for.
    #[derive(Clone, Default, Debug, Deserialize, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct ResultCategories {
        /// Room event results.
        #[serde(default, skip_serializing_if = "ResultRoomEvents::is_empty")]
        pub room_events: ResultRoomEvents,
    }

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

    /// Categories of events that can be searched for.
    #[derive(Clone, Debug, Default, Deserialize, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct ResultRoomEvents {
        /// An approximate count of the total number of results found.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub count: Option<UInt>,

        /// Any groups that were requested.
        #[serde(default, skip_serializing_if = "BTreeMap::is_empty")]
        pub groups: BTreeMap<GroupingKey, BTreeMap<Box<RoomIdOrUserId>, ResultGroup>>,

        /// Token that can be used to get the next batch of results, by passing as the `next_batch`
        /// parameter to the next call.
        ///
        /// If this field is absent, there are no more results.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub next_batch: Option<String>,

        /// List of results in the requested order.
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub results: Vec<SearchResult>,

        /// The current state for every room in the results.
        ///
        /// This is included if the request had the `include_state` key set with a value of `true`.
        #[serde(default, skip_serializing_if = "BTreeMap::is_empty")]
        pub state: BTreeMap<Box<RoomId>, Vec<Raw<AnyStateEvent>>>,

        /// List of words which should be highlighted, useful for stemming which may
        /// change the query terms.
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub highlights: Vec<String>,
    }

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

        /// Returns `true` if all fields are empty / `None`.
        pub fn is_empty(&self) -> bool {
            self.count.is_none()
                && self.groups.is_empty()
                && self.next_batch.is_none()
                && self.results.is_empty()
                && self.state.is_empty()
                && self.highlights.is_empty()
        }
    }

    /// A grouping of results, if requested.
    #[derive(Clone, Debug, Default, Deserialize, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct ResultGroup {
        /// Token that can be used to get the next batch of results in the group, by passing as the
        /// `next_batch` parameter to the next call.
        ///
        /// If this field is absent, there are no more results in this group.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub next_batch: Option<String>,

        /// Key that can be used to order different groups.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub order: Option<UInt>,

        /// Which results are in this group.
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub results: Vec<Box<EventId>>,
    }

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

        /// Returns `true` if all fields are empty / `None`.
        pub fn is_empty(&self) -> bool {
            self.next_batch.is_none() && self.order.is_none() && self.results.is_empty()
        }
    }

    /// A search result.
    #[derive(Clone, Debug, Default, Deserialize, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct SearchResult {
        /// Context for result, if requested.
        #[serde(skip_serializing_if = "EventContextResult::is_empty")]
        pub context: EventContextResult,

        /// A number that describes how closely this result matches the search.
        ///
        /// Higher is closer.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub rank: Option<UInt>,

        /// The event that matched.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub result: Option<Raw<AnyRoomEvent>>,
    }

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

        /// Returns `true` if all fields are empty / `None`.
        pub fn is_empty(&self) -> bool {
            self.context.is_empty() && self.rank.is_none() && self.result.is_none()
        }
    }

    /// A user profile.
    #[derive(Clone, Debug, Default, Deserialize, Serialize)]
    #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
    pub struct UserProfile {
        /// The user's avatar URL, if set.
        ///
        /// 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_common::serde::empty_string_as_none")
        )]
        pub avatar_url: Option<Box<MxcUri>>,

        /// The user's display name, if set.
        #[serde(skip_serializing_if = "Option::is_none")]
        pub displayname: Option<String>,
    }

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

        /// Returns `true` if all fields are `None`.
        pub fn is_empty(&self) -> bool {
            self.avatar_url.is_none() && self.displayname.is_none()
        }
    }

    /// Represents either a room or user ID for returning grouped search results.
    #[derive(Clone, Debug, Deserialize, Eq, Ord, PartialEq, PartialOrd, Serialize)]
    #[allow(clippy::exhaustive_enums)]
    pub enum RoomIdOrUserId {
        /// Represents a room ID.
        RoomId(Box<RoomId>),

        /// Represents a user ID.
        UserId(Box<UserId>),
    }
}