use crate::error::RoomError;
use crate::service::RoomService;
use crate::ws_context::WsUserContext;
use chrono::Utc;
use models::rooms::{room_message, room_message_reaction};
use models::{DateTimeUtc, MessageId, RoomId, RoomThreadId, Seq, UserId};
use sea_orm::*;
use uuid::Uuid;

impl RoomService {
    pub async fn room_message_search(
        &self,
        room_id: Uuid,
        query: &str,
        limit: Option<u64>,
        offset: Option<u64>,
        ctx: &WsUserContext,
    ) -> Result<super::MessageSearchResponse, RoomError> {
        let user_id = ctx.user_id;
        self.require_room_member(room_id, user_id).await?;

        if query.trim().is_empty() {
            return Ok(super::MessageSearchResponse {
                messages: Vec::new(),
                total: 0,
            });
        }

        let limit = std::cmp::min(limit.unwrap_or(20), 100);
        let offset = offset.unwrap_or(0);

        // PostgreSQL full-text search via raw SQL with parameterized query.
        // plainto_tsquery('simple', $1) is injection-safe — it treats input as text.
        let sql = r#"
            SELECT id, seq, room, sender_type, sender_id, thread, in_reply_to,
                   content, content_type, edited_at, send_at, revoked, revoked_by
            FROM room_message
            WHERE room = $1
              AND content_tsv @@ plainto_tsquery('simple', $2)
              AND revoked IS NULL
            ORDER BY send_at DESC
            LIMIT $3 OFFSET $4"#;

        let stmt = Statement::from_sql_and_values(
            DbBackend::Postgres,
            sql,
            vec![
                room_id.into(),
                query.trim().into(),
                limit.into(),
                offset.into(),
            ],
        );

        let rows: Vec<room_message::Model> = self
            .db
            .query_all_raw(stmt)
            .await?
            .into_iter()
            .map(|row| {
                let sender_type = row
                    .try_get::<String>("", "sender_type")
                    .map(|s| match s.as_str() {
                        "admin" => models::rooms::MessageSenderType::Admin,
                        "owner" => models::rooms::MessageSenderType::Owner,
                        "ai" => models::rooms::MessageSenderType::Ai,
                        "system" => models::rooms::MessageSenderType::System,
                        "tool" => models::rooms::MessageSenderType::Tool,
                        "guest" => models::rooms::MessageSenderType::Guest,
                        _ => models::rooms::MessageSenderType::Member,
                    })
                    .unwrap_or(models::rooms::MessageSenderType::Member);

                let content_type = row
                    .try_get::<String>("", "content_type")
                    .map(|s| match s.as_str() {
                        "image" => models::rooms::MessageContentType::Image,
                        "audio" => models::rooms::MessageContentType::Audio,
                        "video" => models::rooms::MessageContentType::Video,
                        "file" => models::rooms::MessageContentType::File,
                        _ => models::rooms::MessageContentType::Text,
                    })
                    .unwrap_or(models::rooms::MessageContentType::Text);

                room_message::Model {
                    id: row.try_get::<MessageId>("", "id").unwrap_or_default(),
                    seq: row.try_get::<Seq>("", "seq").unwrap_or_default(),
                    room: row.try_get::<RoomId>("", "room").unwrap_or_default(),
                    sender_type,
                    sender_id: row
                        .try_get::<Option<UserId>>("", "sender_id")
                        .ok()
                        .flatten(),
                    thread: row
                        .try_get::<Option<RoomThreadId>>("", "thread")
                        .ok()
                        .flatten(),
                    in_reply_to: row
                        .try_get::<Option<MessageId>>("", "in_reply_to")
                        .ok()
                        .flatten(),
                    content: row.try_get::<String>("", "content").unwrap_or_default(),
                    content_type,
                    edited_at: row
                        .try_get::<Option<DateTimeUtc>>("", "edited_at")
                        .ok()
                        .flatten(),
                    send_at: row
                        .try_get::<DateTimeUtc>("", "send_at")
                        .unwrap_or_default(),
                    revoked: row
                        .try_get::<Option<DateTimeUtc>>("", "revoked")
                        .ok()
                        .flatten(),
                    revoked_by: row
                        .try_get::<Option<UserId>>("", "revoked_by")
                        .ok()
                        .flatten(),
                    content_tsv: None,
                }
            })
            .collect();

        // Efficient COUNT query.
        let count_sql = r#"
            SELECT COUNT(*) AS count
            FROM room_message
            WHERE room = $1
              AND content_tsv @@ plainto_tsquery('simple', $2)
              AND revoked IS NULL"#;

        let count_stmt = Statement::from_sql_and_values(
            DbBackend::Postgres,
            count_sql,
            vec![room_id.into(), query.trim().into()],
        );

        let count_row = self.db.query_one_raw(count_stmt).await?;
        let total: i64 = count_row
            .and_then(|r| r.try_get::<i64>("", "count").ok())
            .unwrap_or(0);

        let response_messages = self.build_messages_with_display_names(rows).await;

        Ok(super::MessageSearchResponse {
            messages: response_messages,
            total,
        })
    }

    pub async fn room_message_reaction_list(
        &self,
        room_id: Uuid,
        message_id: Uuid,
        ctx: &WsUserContext,
    ) -> Result<super::MessageReactionsResponse, RoomError> {
        let user_id = ctx.user_id;
        self.require_room_member(room_id, user_id).await?;

        let _msg = room_message::Entity::find_by_id(message_id)
            .one(&self.db)
            .await?
            .ok_or_else(|| RoomError::NotFound("Message not found".to_string()))?;

        self.get_message_reactions(message_id, Some(user_id)).await
    }

    pub async fn room_message_reaction_toggle(
        &self,
        room_id: Uuid,
        message_id: Uuid,
        emoji: String,
        ctx: &WsUserContext,
    ) -> Result<super::MessageReactionsResponse, RoomError> {
        let user_id = ctx.user_id;
        self.require_room_member(room_id, user_id).await?;

        if emoji.is_empty() || emoji.len() > 50 {
            return Err(RoomError::BadRequest("Invalid emoji format".to_string()));
        }

        if let Some(existing) = room_message_reaction::Entity::find()
            .filter(room_message_reaction::Column::Room.eq(room_id))
            .filter(room_message_reaction::Column::Message.eq(message_id))
            .filter(room_message_reaction::Column::User.eq(user_id))
            .filter(room_message_reaction::Column::Emoji.eq(&emoji))
            .one(&self.db)
            .await?
        {
            room_message_reaction::Entity::delete_by_id(existing.id)
                .exec(&self.db)
                .await?;
        } else {
            room_message_reaction::ActiveModel {
                id: Set(Uuid::now_v7()),
                room: Set(room_id),
                message: Set(message_id),
                user: Set(user_id),
                emoji: Set(emoji),
                created_at: Set(Utc::now()),
            }
            .insert(&self.db)
            .await?;
        }

        self.get_message_reactions(message_id, Some(user_id)).await
    }

    pub async fn room_message_edit_history(
        &self,
        room_id: Uuid,
        message_id: Uuid,
        ctx: &WsUserContext,
    ) -> Result<super::MessageEditHistoryResponse, RoomError> {
        let user_id = ctx.user_id;
        self.require_room_member(room_id, user_id).await?;

        let _msg = room_message::Entity::find_by_id(message_id)
            .one(&self.db)
            .await?
            .ok_or_else(|| RoomError::NotFound("Message not found".to_string()))?;

        let history = models::rooms::room_message_edit_history::Entity::find()
            .filter(models::rooms::room_message_edit_history::Column::Message.eq(message_id))
            .order_by_asc(models::rooms::room_message_edit_history::Column::EditedAt)
            .all(&self.db)
            .await?;

        let total_edits = history.len() as i64;

        let entries: Vec<super::MessageEditHistoryEntry> = history
            .into_iter()
            .map(|h| super::MessageEditHistoryEntry {
                old_content: h.old_content,
                new_content: h.new_content,
                edited_at: h.edited_at,
            })
            .collect();

        Ok(super::MessageEditHistoryResponse {
            message_id,
            history: entries,
            total_edits,
        })
    }

    pub async fn room_member_leave(
        &self,
        room_id: Uuid,
        ctx: &WsUserContext,
    ) -> Result<(), RoomError> {
        let user_id = ctx.user_id;

        let member = self
            .find_room_member(room_id, user_id)
            .await?
            .ok_or_else(|| RoomError::NotFound("You are not a member of this room".to_string()))?;

        if member.role.to_string() == "owner" {
            return Err(RoomError::BadRequest(
                "Owner cannot leave the room. Transfer ownership first.".to_string(),
            ));
        }

        models::rooms::room_member::Entity::delete_by_id((room_id, user_id))
            .exec(&self.db)
            .await?;

        self.room_manager.unsubscribe(room_id, user_id).await;

        let room = self.find_room_or_404(room_id).await?;
        self.publish_room_event(
            room.project,
            super::RoomEventType::MemberRemoved,
            Some(room_id),
            None,
            None,
            None,
        )
        .await;

        Ok(())
    }
}