use crate::error::RoomError;
use crate::service::RoomService;
use crate::ws_context::WsUserContext;
use chrono::Utc;
use models::rooms::{room, room_ai, room_attachment, room_category, room_message, room_message_edit_history, room_message_reaction, room_notifications, room_pin, room_thread, room_access, room_user_state};
use queue::ProjectRoomEvent;
use sea_orm::*;
use uuid::Uuid;

impl RoomService {
    pub async fn room_create(
        &self,
        project_name: String,
        request: super::RoomCreateRequest,
        ctx: &WsUserContext,
    ) -> Result<super::RoomResponse, RoomError> {
        let user_id = ctx.user_id;
        let project = self.utils_find_project_by_name(project_name).await?;
        self.require_project_admin(project.id, user_id).await?;
        Self::validate_name(&request.room_name, super::MAX_ROOM_NAME_LEN)?;

        if let Some(category_id) = request.category {
            let category = room_category::Entity::find_by_id(category_id)
                .one(&self.db)
                .await?
                .ok_or_else(|| RoomError::NotFound("Room category not found".to_string()))?;
            if category.project != project.id {
                return Err(RoomError::BadRequest("category does not belong to this project".to_string()));
            }
        }

        let txn = self.db.begin().await?;
        let room_name = request.room_name.clone();
        let room_model = room::ActiveModel {
            id: Set(Uuid::now_v7()),
            project: Set(project.id),
            room_name: Set(request.room_name),
            public: Set(request.public),
            category: Set(request.category),
            created_by: Set(user_id),
            created_at: Set(Utc::now()),
            last_msg_at: Set(Utc::now()),
        }.insert(&txn).await?;

        // Create room_user_state for creator
        room_user_state::ActiveModel {
            room: Set(room_model.id),
            user: Set(user_id),
            last_read_seq: Set(None),
            do_not_disturb: Set(false),
            dnd_start_hour: Set(None),
            dnd_end_hour: Set(None),
            joined_at: Set(Some(Utc::now())),
        }.insert(&txn).await?;

        // For private rooms, creator is auto-granted access
        if !request.public {
            room_access::ActiveModel {
                room: Set(room_model.id),
                user: Set(user_id),
                granted_by: Set(user_id),
                granted_at: Set(Utc::now()),
            }.insert(&txn).await?;
        }

        txn.commit().await?;
        self.invalidate_room_list_cache(project.id).await;
        self.spawn_room_workers(room_model.id);

        let event = ProjectRoomEvent {
            event_type: super::RoomEventType::RoomCreated.as_str().into(),
            project_id: project.id,
            room_id: Some(room_model.id),
            category_id: None,
            message_id: None,
            seq: None,
            timestamp: Utc::now(),
        };
        let _ = self.queue.publish_project_room_event(project.id, event).await;

        self.notify_project_members(
            project.id,
            super::NotificationType::RoomCreated,
            format!("新房间已创建: {}", room_name),
            None,
            Some(room_model.id),
        );

        let version = Self::raw_increment_room_version(&self.cache, room_model.id).await?;
        let mut resp = super::RoomResponse::from(room_model);
        resp.version = version;
        observability::incr!(observability::ROOMS_CREATED_TOTAL);
        Ok(resp)
    }

    pub async fn room_update(
        &self,
        room_id: Uuid,
        request: super::RoomUpdateRequest,
        ctx: &WsUserContext,
    ) -> Result<super::RoomResponse, RoomError> {
        let user_id = ctx.user_id;
        let room_model = self.find_room_or_404(room_id).await?;
        self.require_room_admin(room_id, user_id).await?;

        if let Some(category_id) = request.category {
            let category = room_category::Entity::find_by_id(category_id)
                .one(&self.db)
                .await?
                .ok_or_else(|| RoomError::NotFound("Room category not found".to_string()))?;
            if category.project != room_model.project {
                return Err(RoomError::BadRequest("category does not belong to this project".to_string()));
            }
        }

        let mut active: room::ActiveModel = room_model.into();
        let renamed = request.room_name.is_some();
        let moved = request.category.is_some();

        if let Some(name) = request.room_name {
            active.room_name = Set(name);
        }
        if let Some(public) = request.public {
            active.public = Set(public);
        }
        if request.category.is_some() {
            active.category = Set(request.category);
        }
        let updated = active.update(&self.db).await?;

        self.invalidate_room_list_cache(updated.project).await;

        if renamed {
            let event = ProjectRoomEvent {
                event_type: super::RoomEventType::RoomRenamed.as_str().into(),
                project_id: updated.project,
                room_id: Some(updated.id),
                category_id: None,
                message_id: None,
                seq: None,
                timestamp: Utc::now(),
            };
            let _ = self.queue.publish_project_room_event(updated.project, event).await;
        }
        if moved {
            let event = ProjectRoomEvent {
                event_type: super::RoomEventType::RoomMoved.as_str().into(),
                project_id: updated.project,
                room_id: Some(updated.id),
                category_id: None,
                message_id: None,
                seq: None,
                timestamp: Utc::now(),
            };
            let _ = self.queue.publish_project_room_event(updated.project, event).await;
        }

        let version = self.increment_room_version(room_id).await?;
        let mut resp = super::RoomResponse::from(updated);
        resp.version = version;
        Ok(resp)
    }

    pub async fn room_delete(&self, room_id: Uuid, ctx: &WsUserContext) -> Result<(), RoomError> {
        let user_id = ctx.user_id;
        let room_model = self.find_room_or_404(room_id).await?;
        self.require_room_admin(room_id, user_id).await?;
        let project_id = room_model.project;

        let txn = self.db.begin().await?;

        room_attachment::Entity::delete_many().filter(room_attachment::Column::Room.eq(room_id)).exec(&txn).await?;
        room_message::Entity::delete_many().filter(room_message::Column::Room.eq(room_id)).exec(&txn).await?;
        room_pin::Entity::delete_many().filter(room_pin::Column::Room.eq(room_id)).exec(&txn).await?;
        room_thread::Entity::delete_many().filter(room_thread::Column::Room.eq(room_id)).exec(&txn).await?;
        room_access::Entity::delete_many().filter(room_access::Column::Room.eq(room_id)).exec(&txn).await?;
        room_user_state::Entity::delete_many().filter(room_user_state::Column::Room.eq(room_id)).exec(&txn).await?;
        room_ai::Entity::delete_many().filter(room_ai::Column::Room.eq(room_id)).exec(&txn).await?;
        room_message_reaction::Entity::delete_many().filter(room_message_reaction::Column::Room.eq(room_id)).exec(&txn).await?;

        let subquery = room_message::Entity::find()
            .filter(room_message::Column::Room.eq(room_id))
            .select_only()
            .column(room_message::Column::Id)
            .into_query();
        room_message_edit_history::Entity::delete_many()
            .filter(room_message_edit_history::Column::Message.in_subquery(subquery))
            .exec(&txn)
            .await?;

        room_notifications::Entity::delete_many().filter(room_notifications::Column::Room.eq(room_id)).exec(&txn).await?;
        room::Entity::delete_by_id(room_id).exec(&txn).await?;

        txn.commit().await?;
        self.invalidate_room_list_cache(project_id).await;
        self.room_manager.shutdown_room(room_id).await;

        let seq_key = format!("room:seq:{}", room_id);
        if let Ok(mut conn) = self.cache.conn().await {
            let _: Option<String> = redis::cmd("DEL").arg(&seq_key).query_async(&mut conn).await
                .inspect_err(|e| {
                    tracing::warn!(seq_key = %seq_key, error = %e, "room_delete: failed to DEL seq key");
                }).ok();
        }

        let event = ProjectRoomEvent {
            event_type: super::RoomEventType::RoomDeleted.as_str().into(),
            project_id,
            room_id: Some(room_id),
            category_id: None,
            message_id: None,
            seq: None,
            timestamp: Utc::now(),
        };
        let _ = self.queue.publish_project_room_event(project_id, event).await;

        self.notify_project_members(
            project_id,
            super::NotificationType::RoomDeleted,
            format!("房间 {} 已被删除", room_model.room_name),
            None,
            Some(room_id),
        );

        observability::incr!(observability::ROOMS_DELETED_TOTAL);
        Ok(())
    }
}