mod access;
mod access_write;
mod ai_common;
mod ai_mode_streaming;
mod ai_mode_streaming_post;
mod ai_mode_streaming_steps;
mod ai_nonstreaming;
mod ai_react_nonstreaming;
mod ai_react_streaming;
mod ai_react_streaming_post;
mod ai_react_streaming_steps;
mod ai_service;
mod ai_streaming;
mod history;
mod mentions;
mod notifications;
mod patterns;
mod process_ai;
mod sequence;
mod type_convert;
mod validation;
mod workers;
mod workers_spawn;

pub use patterns::{mention_bracket_re, mention_tag_re, user_mention_re};

pub use access::{
    check_project_member, check_room_access, find_room_or_404, get_or_create_room_user_state,
    is_project_admin, is_room_admin, require_project_admin, require_room_access,
    require_room_admin,
};
pub use ai_common::create_and_publish_ai_message;
pub use ai_nonstreaming::process_message_ai_nonstreaming;
pub use ai_react_nonstreaming::process_message_ai_react_nonstreaming;
pub use ai_react_streaming::process_message_ai_react_streaming;
pub use ai_service::RoomAiService;
pub use ai_streaming::process_message_ai_streaming;
pub use history::{extract_mention_context, get_room_ai_config, get_room_history, get_user_names};
pub use mentions::extract_mentions;
pub use notifications::{notify_project_members, publish_room_event};
pub use sequence::next_room_message_seq_internal;
pub use workers::{PushNotificationFn, start_workers};
pub use workers_spawn::{spawn_agent_task, spawn_room_workers, unmark_room_spawned};

use std::sync::Arc;

use chrono::Utc;
use db::cache::AppCache;
use db::database::AppDatabase;
use models::rooms::room;
use models::rooms::room_ai;
use queue::{MessageProducer, ProjectRoomEvent};
use sea_orm::{ColumnTrait, QueryFilter};
use uuid::Uuid;

use crate::connection::{DedupCache, RoomConnectionManager};
use crate::error::RoomError;
use crate::presence::PresenceStore;
use agent::TaskService;
use agent::chat::ChatService;
use agent::embed::EmbedService;
use models::agent_task::AgentType;

const DEFAULT_MAX_CONCURRENT_WORKERS: usize = 1024;

#[derive(Clone)]
pub struct RoomService {
    pub db: AppDatabase,
    pub cache: AppCache,
    pub config: config::AppConfig,
    pub room_manager: Arc<RoomConnectionManager>,
    pub queue: MessageProducer,
    pub nats: Option<Arc<queue::NatsClient>>,
    pub chat_service: Option<Arc<ChatService>>,
    pub task_service: Option<Arc<TaskService>>,
    pub embed_service: Option<Arc<EmbedService>>,
    pub push_fn: Option<workers::PushNotificationFn>,
    pub ai_service: RoomAiService,
    pub presence: PresenceStore,
    worker_semaphore: Arc<tokio::sync::Semaphore>,
    dedup_cache: DedupCache,
}

impl RoomService {
    pub fn new(
        db: AppDatabase,
        cache: AppCache,
        config: config::AppConfig,
        queue: MessageProducer,
        room_manager: Arc<RoomConnectionManager>,
        nats: Option<Arc<queue::NatsClient>>,
        chat_service: Option<Arc<ChatService>>,
        task_service: Option<Arc<TaskService>>,
        max_concurrent_workers: Option<usize>,
        push_fn: Option<workers::PushNotificationFn>,
        embed_service: Option<Arc<EmbedService>>,
    ) -> Self {
        let dedup_cache: DedupCache = Arc::new(dashmap::DashMap::with_capacity_and_hasher(
            10000,
            Default::default(),
        ));
        let ai_service = RoomAiService::new(
            db.clone(),
            cache.clone(),
            config.clone(),
            queue.clone(),
            room_manager.clone(),
            chat_service.clone(),
        );
        Self {
            db,
            cache,
            config,
            room_manager,
            queue,
            nats,
            chat_service,
            task_service,
            embed_service,
            ai_service,
            worker_semaphore: Arc::new(tokio::sync::Semaphore::new(
                max_concurrent_workers.unwrap_or(DEFAULT_MAX_CONCURRENT_WORKERS),
            )),
            dedup_cache,
            push_fn,
            presence: PresenceStore::new(),
        }
    }

    pub async fn start_workers(
        &self,
        shutdown_rx: tokio::sync::broadcast::Receiver<()>,
    ) -> anyhow::Result<()> {
        workers::start_workers(
            self.db.clone(),
            self.cache.clone(),
            self.room_manager.clone(),
            self.queue.clone(),
            self.nats.clone(),
            self.dedup_cache.clone(),
            self.task_service.clone(),
            None, // max_concurrent_workers handled by semaphore
            shutdown_rx,
            self.embed_service.clone(),
        )
        .await
    }

    pub async fn spawn_agent_task<F, Fut>(
        &self,
        project_id: Uuid,
        agent_type: AgentType,
        input: String,
        _title: Option<String>,
        execute: F,
    ) -> anyhow::Result<i64>
    where
        F: FnOnce(i64, Arc<TaskService>) -> Fut + Send + 'static,
        Fut: std::future::Future<Output = Result<String, String>> + Send,
    {
        let task_service = match &self.task_service {
            Some(ts) => ts.clone(),
            None => return Err(anyhow::anyhow!("task service not configured")),
        };

        workers_spawn::spawn_agent_task(
            project_id,
            agent_type,
            input,
            task_service,
            self.queue.clone(),
            self.room_manager.clone(),
            self.worker_semaphore.clone(),
            execute,
        )
        .await
    }

    pub fn spawn_room_workers(&self, room_id: uuid::Uuid) {
        workers_spawn::spawn_room_workers(
            room_id,
            self.db.clone(),
            self.room_manager.clone(),
            self.queue.clone(),
            self.nats.clone(),
            self.worker_semaphore.clone(),
            self.embed_service.clone(),
        );
    }

    pub async fn publish_room_event(
        &self,
        project_id: uuid::Uuid,
        event_type: super::RoomEventType,
        room_id: Option<uuid::Uuid>,
        category_id: Option<uuid::Uuid>,
        message_id: Option<uuid::Uuid>,
        seq: Option<i64>,
    ) {
        let event = ProjectRoomEvent {
            event_type: event_type.as_str().into(),
            project_id,
            room_id,
            category_id,
            message_id,
            seq,
            timestamp: Utc::now(),
        };
        self.queue
            .publish_project_room_event(project_id, event)
            .await;
    }

    pub fn notify_project_members(
        &self,
        project_id: uuid::Uuid,
        notification_type: super::NotificationType,
        title: String,
        content: Option<String>,
        related_room_id: Option<uuid::Uuid>,
    ) {
        notifications::notify_project_members(
            self.db.clone(),
            project_id,
            notification_type,
            title,
            content,
            related_room_id,
        );
    }

    pub fn extract_mentions(content: &str) -> Vec<Uuid> {
        mentions::extract_mentions(content)
    }

    pub async fn resolve_mentions(&self, content: &str) -> Vec<Uuid> {
        use models::users::User;
        use sea_orm::EntityTrait;
        let mut resolved = Vec::new();
        let mut seen_usernames = Vec::new();
        for cap in mention_bracket_re().captures_iter(content) {
            if let (Some(type_m), Some(id_m)) = (cap.get(1), cap.get(2)) {
                if type_m.as_str() == "user" {
                    let id = id_m.as_str().trim();
                    if let Ok(uuid) = Uuid::parse_str(id) {
                        if !resolved.contains(&uuid) {
                            resolved.push(uuid);
                        }
                    } else if let Some(label_m) = cap.get(3) {
                        let label = label_m.as_str().trim();
                        if !label.is_empty() {
                            let label_lower = label.to_lowercase();
                            if seen_usernames.contains(&label_lower) {
                                continue;
                            }
                            seen_usernames.push(label_lower.clone());

                            if let Some(user) = User::find()
                                .filter(models::users::user::Column::Username.ilike(&label_lower))
                                .one(&self.db)
                                .await
                                .ok()
                                .flatten()
                            {
                                if !resolved.contains(&user.uid) {
                                    resolved.push(user.uid);
                                }
                            }
                        }
                    }
                }
            }
        }
        resolved
    }

    pub async fn check_room_access(&self, room_id: Uuid, user_id: Uuid) -> Result<(), RoomError> {
        access::check_room_access(&self.db, room_id, user_id).await
    }

    pub async fn check_project_member(
        &self,
        project_id: Uuid,
        user_id: Uuid,
    ) -> Result<(), RoomError> {
        access::check_project_member(&self.db, project_id, user_id).await
    }

    pub async fn should_ai_respond(&self, room_id: Uuid, content: &str) -> Result<bool, RoomError> {
        self.ai_service.should_respond(room_id, content).await
    }

    pub async fn get_room_ai_config(
        &self,
        room_id: Uuid,
    ) -> Result<Option<room_ai::Model>, RoomError> {
        history::get_room_ai_config(&self.db, room_id).await
    }

    pub async fn get_user_names(
        &self,
        user_ids: &[Uuid],
    ) -> std::collections::HashMap<Uuid, String> {
        history::get_user_names(&self.db, user_ids).await
    }

    pub async fn require_room_access(&self, room_id: Uuid, user_id: Uuid) -> Result<(), RoomError> {
        access::require_room_access(&self.db, room_id, user_id).await
    }

    pub async fn require_room_admin(&self, room_id: Uuid, user_id: Uuid) -> Result<(), RoomError> {
        access::require_room_admin(&self.db, room_id, user_id).await
    }

    pub async fn is_room_admin(&self, room_id: Uuid, user_id: Uuid) -> bool {
        access::is_room_admin(&self.db, room_id, user_id).await
    }

    pub async fn require_project_admin(
        &self,
        project_id: Uuid,
        user_id: Uuid,
    ) -> Result<(), RoomError> {
        access::require_project_admin(&self.db, project_id, user_id).await
    }

    pub async fn find_room_or_404(&self, room_id: Uuid) -> Result<room::Model, RoomError> {
        access::find_room_or_404(&self.db, room_id).await
    }

    // ─── Presence Methods ─────────────────────────────────────────────────────

    /// Set user presence in a project context and broadcast to project subscribers.
    /// Returns the local PresenceChanged type - caller is responsible for conversion.
    pub async fn set_user_presence(
        &self,
        user_id: Uuid,
        project_id: Option<Uuid>,
        status: crate::presence::PresenceStatus,
    ) -> Option<crate::presence::PresenceChanged> {
        let event = self.presence.set_presence(user_id, project_id, status);
        if event.is_some() {
            // Broadcast to project subscribers
            if let Some(pid) = project_id {
                self.room_manager
                    .broadcast_project(
                        pid,
                        queue::ProjectRoomEvent {
                            event_type: "presence_changed".into(),
                            project_id: pid,
                            room_id: None,
                            category_id: None,
                            message_id: None,
                            seq: None,
                            timestamp: chrono::Utc::now(),
                        },
                    )
                    .await;
            }
        }
        event
    }

    /// Set user custom status (emoji, text).
    pub fn set_custom_status(
        &self,
        user_id: Uuid,
        emoji: Option<String>,
        text: Option<String>,
        expires_at: Option<chrono::DateTime<chrono::Utc>>,
    ) -> Option<crate::presence::CustomStatusChanged> {
        self.presence
            .set_custom_status(user_id, emoji, text, expires_at)
    }

    /// Get all presence entries for a project.
    pub fn get_project_presence(&self, project_id: Uuid) -> Vec<crate::presence::PresenceChanged> {
        self.presence.get_project_presence(project_id)
    }

    /// Remove user presence when they disconnect.
    pub async fn remove_user_presence(
        &self,
        user_id: Uuid,
        project_id: Option<Uuid>,
    ) -> Option<crate::presence::PresenceChanged> {
        let event = self.presence.remove_presence(user_id, project_id);
        if event.is_some() {
            // Broadcast to project subscribers
            if let Some(pid) = project_id {
                self.room_manager
                    .broadcast_project(
                        pid,
                        queue::ProjectRoomEvent {
                            event_type: "presence_changed".into(),
                            project_id: pid,
                            room_id: None,
                            category_id: None,
                            message_id: None,
                            seq: None,
                            timestamp: chrono::Utc::now(),
                        },
                    )
                    .await;
            }
        }
        event
    }
}