moduforge-collaboration 0.4.5

use std::sync::Arc;
use yrs::{Map, ReadTxn as _, Transact, WriteTxn as _};
use serde::{Deserialize, Serialize};

use crate::{mapping::Mapper};
use crate::error::Result;
use crate::yrs_manager::YrsManager;
use moduforge_state::Transaction;
use moduforge_model::tree::Tree;
use crate::RoomSnapshot;

/// 房间状态枚举
#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
pub enum RoomStatus {
    /// 房间不存在
    NotExists,
    /// 房间已创建但未初始化数据
    Created,
    /// 房间已初始化并有数据
    Initialized,
    /// 房间正在下线中
    Shutting,
    /// 房间已下线
    Offline,
}

/// 房间信息结构
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct RoomInfo {
    pub room_id: String,
    pub status: RoomStatus,
    pub node_count: usize,
    pub client_count: usize,
    pub last_activity: std::time::SystemTime,
}

#[derive(Clone)]
pub struct SyncService {
    yrs_manager: Arc<YrsManager>,
    client_id: u64,
}

impl SyncService {
    pub fn new(yrs_manager: Arc<YrsManager>) -> Self {
        Self { yrs_manager, client_id: fastrand::u64(..) }
    }

    /// 初始化房间，确保 Yrs 文档存在
    pub fn init_room(
        &self,
        room_id: &str,
    ) {
        tracing::info!("🔄 初始化房间: {}", room_id);
        self.yrs_manager.get_or_create_awareness(room_id);
    }

    /// 使用现有的 Tree 初始化房间，同步所有节点数据到 Yrs 文档
    /// 这是在房间首次创建或需要重新同步时调用的关键方法
    pub async fn init_room_with_tree(
        &self,
        room_id: &str,
        tree: &Tree,
    ) -> Result<()> {
        tracing::info!("🔄 初始化房间: {} 使用现有的树数据", room_id);

        // 获取或创建 awareness
        let awareness_ref = self.yrs_manager.get_or_create_awareness(room_id);
        let mut awareness = awareness_ref.write().await;
        let doc = awareness.doc_mut();
        let mut txn = doc.transact_mut_with(yrs::Origin::from(self.client_id));

        // 清空现有数据（如果有的话）
        let nodes_map = txn.get_or_insert_map("nodes");
        nodes_map.clear(&mut txn);

        // 同步 Tree 中的所有节点到 Yrs 文档
        self.sync_tree_to_yrs(tree, &mut txn)?;

        // 提交事务
        txn.commit();

        tracing::info!(
            "Successfully initialized room {} with tree containing {} nodes",
            room_id,
            tree.nodes.len()
        );
        Ok(())
    }

    /// 将 Tree 中的所有节点同步到 Yrs 事务中
    fn sync_tree_to_yrs(
        &self,
        tree: &Tree,
        txn: &mut yrs::TransactionMut,
    ) -> Result<()> {
        use moduforge_transform::{step::Step, node_step::AddNodeStep};

        let registry = Mapper::global_registry();

        // 获取根节点的所有子树
        if let Some(root_tree) = tree.all_children(&tree.root_id, None) {
            // 创建一个 AddNodeStep 来添加整个子树
            let add_step = AddNodeStep {
                parent_id: tree.root_id.clone(),
                nodes: vec![root_tree],
            };

            // 使用现有的转换器应用步骤
            if let Some(converter) =
                registry.find_converter(&add_step as &dyn Step)
            {
                if let Err(e) =
                    converter.apply_to_yrs_txn(&add_step as &dyn Step, txn)
                {
                    tracing::error!("🔄 同步树节点到 Yrs 失败: {}", e);
                    return Err(crate::error::TransmissionError::SyncError(
                        format!("Failed to sync tree: {}", e),
                    ));
                }
            } else {
                tracing::error!(
                    "🔄 同步树节点到 Yrs 失败: 没有找到 AddNodeStep 的转换器"
                );
                return Err(crate::error::TransmissionError::SyncError(
                    "No converter found for AddNodeStep".to_string(),
                ));
            }
        }

        Ok(())
    }

    /// 处理多个业务逻辑事务并批量应用到 Yrs 文档
    pub async fn handle_transaction_applied(
        &self,
        transactions: &[Transaction],
        room_id: &str,
    ) -> Result<()> {
        // 使用异步锁获取房间信息
        if let Some(awareness_ref) = self.yrs_manager.get_awareness_ref(room_id)
        {
            let mut awareness = awareness_ref.write().await;
            let doc = awareness.doc_mut();
            let mut txn =
                doc.transact_mut_with(yrs::Origin::from(self.client_id));

            // 使用全局注册表应用所有事务中的步骤
            let registry = Mapper::global_registry();

            for tr in transactions {
                let steps = &tr.steps;
                for step in steps {
                    if let Some(converter) =
                        registry.find_converter(step.as_ref())
                    {
                        if let Err(e) =
                            converter.apply_to_yrs_txn(step.as_ref(), &mut txn)
                        {
                            tracing::error!(
                                "🔄 应用步骤到 Yrs 事务失败: {}",
                                e
                            );
                        }
                    } else {
                        let type_name =
                            std::any::type_name_of_val(step.as_ref());
                        tracing::warn!(
                            "🔄 应用步骤到 Yrs 事务失败: 没有找到步骤的转换器: {}",
                            type_name
                        );
                    }
                }
            }

            // 统一提交所有更改
            txn.commit();
            tracing::debug!(
                "🔄 应用 {} 个事务到房间: {}",
                transactions.len(),
                room_id
            );
        }

        Ok(())
    }

    /// 获取房间的完整快照（用于新客户端初始化）
    pub fn get_room_snapshot(
        &self,
        room_id: &str,
        tree: &Tree,
    ) -> RoomSnapshot {
        tracing::debug!("🔄 获取房间快照: {}", room_id);
        Mapper::tree_to_snapshot(tree, room_id.to_string())
    }

    /// 检查房间是否已初始化（有数据）
    pub async fn is_room_initialized(
        &self,
        room_id: &str,
    ) -> bool {
        if let Some(awareness_ref) = self.yrs_manager.get_awareness_ref(room_id)
        {
            let awareness = awareness_ref.read().await;
            let doc = awareness.doc();
            let txn = doc.transact();

            if let Some(nodes_map) = txn.get_map("nodes") {
                nodes_map.len(&txn) > 0
            } else {
                false
            }
        } else {
            false
        }
    }

    /// 获取房间状态信息
    pub async fn get_room_status(
        &self,
        room_id: &str,
    ) -> RoomStatus {
        if !self.yrs_manager.room_exists(room_id) {
            return RoomStatus::NotExists;
        }

        if self.is_room_initialized(room_id).await {
            RoomStatus::Initialized
        } else {
            RoomStatus::Created
        }
    }

    /// 获取房间详细信息
    pub async fn get_room_info(
        &self,
        room_id: &str,
    ) -> Option<RoomInfo> {
        if !self.yrs_manager.room_exists(room_id) {
            return None;
        }

        let status = self.get_room_status(room_id).await;
        let mut node_count = 0;
        let mut client_count = 0;

        if let Some(awareness_ref) = self.yrs_manager.get_awareness_ref(room_id)
        {
            if let Ok(awareness) = awareness_ref.try_read() {
                let doc = awareness.doc();
                let txn = doc.transact();

                // 获取节点数量
                if let Some(nodes_map) = txn.get_map("nodes") {
                    node_count = nodes_map.len(&txn);
                }

                // 获取客户端数量
                client_count = awareness.clients().len();
            }
        }

        Some(RoomInfo {
            room_id: room_id.to_string(),
            status,
            node_count: node_count as usize,
            client_count,
            last_activity: std::time::SystemTime::now(),
        })
    }

    /// 房间下线 - 核心下线方法
    /// 1. 断开所有客户端
    /// 2. 可选保存数据
    /// 3. 清理资源
    pub async fn offline_room(
        &self,
        room_id: &str,
        save_data: bool,
    ) -> Result<Option<RoomSnapshot>> {
        tracing::info!("🔄 开始下线房间: {}", room_id);

        let mut final_snapshot = None;

        // 1. 检查房间是否存在
        if !self.yrs_manager.room_exists(room_id) {
            tracing::warn!("🔄 尝试下线不存在的房间: {}", room_id);
            return Ok(None);
        }

        // 2. 如果需要保存数据，先创建快照
        if save_data {
            if let Some(awareness_ref) =
                self.yrs_manager.get_awareness_ref(room_id)
            {
                let awareness = awareness_ref.read().await;
                let doc = awareness.doc();
                let txn = doc.transact();

                // 从 Yrs 文档重建 Tree 快照
                if let Some(nodes_map) = txn.get_map("nodes") {
                    let node_count = nodes_map.len(&txn);
                    tracing::info!(
                        "🔄 保存 {} 个节点 from room: {}",
                        node_count,
                        room_id
                    );

                    // 创建简化的快照（实际项目中可能需要完整的 Tree 重建）
                    final_snapshot = Some(RoomSnapshot {
                        room_id: room_id.to_string(),
                        root_id: "root".to_string(), // 简化处理
                        nodes: std::collections::HashMap::new(),
                        version: 0,
                    });
                }
            }
        }

        // 3. 从 YrsManager 中移除房间（这会自动断开客户端）
        if let Some(_awareness_ref) =
            self.yrs_manager.remove_room(room_id).await
        {
            tracing::info!("🔄 房间 '{}' 成功下线", room_id);
        } else {
            tracing::error!("🔄 从 YrsManager 中移除房间 '{}' 失败", room_id);
            return Err(crate::error::TransmissionError::SyncError(format!(
                "Failed to offline room: {}",
                room_id
            )));
        }

        Ok(final_snapshot)
    }

    /// 强制房间下线（用于紧急情况）
    pub async fn force_offline_room(
        &self,
        room_id: &str,
    ) -> Result<bool> {
        tracing::warn!("Force offlining room: {}", room_id);

        let success = self.yrs_manager.force_cleanup_room(room_id).await;

        if success {
            tracing::info!("Room '{}' force offlined successfully", room_id);
        } else {
            tracing::error!("Failed to force offline room: {}", room_id);
        }

        Ok(success)
    }

    /// 批量下线房间
    pub async fn offline_rooms(
        &self,
        room_ids: &[String],
        save_data: bool,
    ) -> Result<Vec<(String, Option<RoomSnapshot>)>> {
        tracing::info!("🔄 批量下线 {} 个房间", room_ids.len());

        let mut results = Vec::new();

        for room_id in room_ids {
            match self.offline_room(room_id, save_data).await {
                Ok(snapshot) => {
                    results.push((room_id.clone(), snapshot));
                },
                Err(e) => {
                    tracing::error!("🔄 下线房间 '{}' 失败: {}", room_id, e);
                    results.push((room_id.clone(), None));
                },
            }
        }

        tracing::info!(
            "🔄 批量下线完成: {}/{} 个房间成功下线",
            results.iter().filter(|(_, snapshot)| snapshot.is_some()).count(),
            room_ids.len()
        );

        Ok(results)
    }

    /// 获取所有活跃房间列表
    pub fn get_active_rooms(&self) -> Vec<String> {
        self.yrs_manager.get_active_rooms()
    }

    /// 获取房间统计信息
    pub async fn get_rooms_stats(&self) -> Vec<RoomInfo> {
        let room_ids = self.get_active_rooms();
        let mut stats = Vec::new();

        for room_id in room_ids {
            if let Some(info) = self.get_room_info(&room_id).await {
                stats.push(info);
            }
        }

        stats
    }

    /// 获取 YrsManager 的引用（用于高级操作）
    pub fn yrs_manager(&self) -> &Arc<YrsManager> {
        &self.yrs_manager
    }
}

impl std::fmt::Debug for SyncService {
    fn fmt(
        &self,
        f: &mut std::fmt::Formatter<'_>,
    ) -> std::fmt::Result {
        f.debug_struct("SyncService")
            .field("client_id", &self.client_id)
            .finish()
    }
}