// stateManager.js
let db = null;

export const initDB = (firebaseDB) => {
    db = firebaseDB;
};

const activeProjects = new Map();



export const StateManager = {
  /**
   * GET PROJECT
   * Hydrates from DB if not in memory.
   * Flattens { info, thumbnail, state } into a usable Memory Object.
   */
  getProject: async (projectId) => {
    // 1. Try Memory
    if (activeProjects.has(projectId)) {
        return activeProjects.get(projectId);
    }

    // 2. Try Firebase (Hydration)
    if (db) {
        try {
            console.log(`[StateManager] 🟡 Hydrating project ${projectId} from DB...`);
            // We fetch the root because the Server AI needs EVERYTHING (context, history) to function.
            // If this was a client-side Dashboard, we would only fetch /info.
            const snapshot = await db.ref(`projects/${projectId}`).once('value');
            
            if (snapshot.exists()) {
                const dbData = snapshot.val();
                
                // FLATTEN DB STRUCTURE -> MEMORY STRUCTURE
                const memoryObject = {
                    ...dbData.info,             // Title, stats, description
                     thumbnail: dbData.thumbnail?.url || null,
                    // State might be undefined if just created, so default it
                    commandQueue: dbData.state?.commandQueue || [],
                    workerHistory: dbData.state?.workerHistory || [],
                    pmHistory: dbData.state?.pmHistory || [],
                    failureCount: dbData.state?.failureCount || 0,
                    gdd: dbData.state?.gdd || null,
                     // CRITICAL: Initialize lastActive to NOW so it doesn't expire immediately
                        lastActive: Date.now(), 
                        lastUpdated: Date.now()
                };
                
                // Load into Memory
                activeProjects.set(projectId, memoryObject);
                console.log(`[StateManager] 🟢 Project ${projectId} hydrated.`);
                return memoryObject;
            }
        } catch (err) {
            console.error(`[StateManager] Error reading DB for ${projectId}:`, err);
        }
    }

    return null; 
  },

  /**
   * UPDATE PROJECT
   * Updates Memory immediately.
   * Performs granular updates to DB (separating Info vs State).
   */
  updateProject: async (projectId, data) => {
    let current = activeProjects.get(projectId);
    
    // Safety check: ensure we have base state
    if (!current) {
        current = await StateManager.getProject(projectId) || { 
            commandQueue: [], workerHistory: [], pmHistory: [], failureCount: 0 
        };
    }

    const timestamp = Date.now();
    
    // 1. Update Memory (Flat Merge)
    const newData = { 
        ...current, 
        ...data, 
           // CRITICAL: Initialize lastActive to NOW so it doesn't expire immediately
       lastActive: Date.now(), 
       lastUpdated: Date.now()
    };
    activeProjects.set(projectId, newData);

    // 2. Update Firebase (Nested Split)
    if (db) {
        const updates = {};
        
        // We assume 'data' contains the specific fields that changed.
        // However, to be safe and robust, we map the current state to the correct buckets.
        
        // Bucket: Info
        if (data.status || data.stats || data.title) {
             updates[`projects/${projectId}/info/status`] = newData.status;
             if (newData.lastUpdated) updates[`projects/${projectId}/info/lastUpdated`] = newData.lastUpdated;
             // Add other info fields if they are mutable
        }

        // Bucket: State (History, Queue, GDD) - This is the most frequent update
        if (data.workerHistory || data.pmHistory || data.commandQueue || data.failureCount || data.gdd) {
            updates[`projects/${projectId}/state/workerHistory`] = newData.workerHistory;
            updates[`projects/${projectId}/state/pmHistory`] = newData.pmHistory;
            updates[`projects/${projectId}/state/commandQueue`] = newData.commandQueue;
            updates[`projects/${projectId}/state/failureCount`] = newData.failureCount;
            if (newData.gdd) updates[`projects/${projectId}/state/gdd`] = newData.gdd;
        }

        // Bucket: Thumbnail (Only update if explicitly passed in 'data', avoiding re-upload of massive string)
        if (data.thumbnail) {
            updates[`projects/${projectId}/thumbnail`] = {url: data.thumbnail};
        }

        // Perform the update
        if (Object.keys(updates).length > 0) {
            db.ref().update(updates).catch(err => {
                console.error(`[StateManager] 🔴 DB Write Failed for ${projectId}:`, err);
            });
        }
    }

    return newData;
  },

  queueCommand: async (projectId, input) => {
    const project = await StateManager.getProject(projectId);
    if (!project) return;
    
    let command = null;

    if (typeof input === 'object' && input.type && input.payload) {
        command = input;
    } 
    else if (typeof input === 'string') {
        const rawResponse = input;
        if (rawResponse.includes("[ASK_PM:")) return;
        if (rawResponse.includes("[GENERATE_IMAGE:") && !rawResponse.includes("```")) return;

        const codeMatch = rawResponse.match(/```(?:lua|luau)?([\s\S]*?)```/i);
        const readScriptMatch = rawResponse.match(/\[READ_SCRIPT:\s*(.*?)\]/);
        const readHierarchyMatch = rawResponse.match(/\[READ_HIERARCHY:\s*(.*?)\]/);
        const readLogsMatch = rawResponse.includes("[READ_LOGS]");

        if (codeMatch) command = { type: "EXECUTE", payload: codeMatch[1].trim() };
        else if (readScriptMatch) command = { type: "READ_SCRIPT", payload: readScriptMatch[1].trim() };
        else if (readHierarchyMatch) command = { type: "READ_HIERARCHY", payload: readHierarchyMatch[1].trim() };
        else if (readLogsMatch) command = { type: "READ_LOGS", payload: null };
    }
        
    if (command) {
      project.commandQueue.push(command);
      console.log(`[${projectId}] Queued Action: ${command.type}`);
      // Sync queue to DB
      await StateManager.updateProject(projectId, { commandQueue: project.commandQueue });
    }
  },
  
  popCommand: async (projectId) => {
    const project = await StateManager.getProject(projectId);
    if (!project || !project.commandQueue.length) return null;
    
    const command = project.commandQueue.shift();
    // Sync queue to DB
    await StateManager.updateProject(projectId, { commandQueue: project.commandQueue });
    
    return command;
  },

  cleanupMemory: () => {
    const now = Date.now();
    const FOUR_HOURS = 4 * 60 * 60 * 1000;
    let count = 0;

    for (const [id, data] of activeProjects.entries()) {
        // FIX: If lastActive is missing/undefined/0, reset it to NOW.
        // This prevents the "54 year old project" bug where (now - 0) > 4 hours.
        if (!data.lastActive) {
            console.warn(`[StateManager] ⚠️ Project ${id} missing timestamp. Healing data...`);
            data.lastActive = now;
            continue; // Skip deleting this round
        }

        if (now - data.lastActive > FOUR_HOURS) {
            console.log(`[StateManager] 🧹 Removing expired project: ${id}`);
            activeProjects.delete(id);
            count++;
        }
    }
    
    if (count > 0) {
        console.log(`[StateManager] 🗑️ Cleaned ${count} projects from memory.`);
    }
    return count;
  }
  
  /* cleanupMemory: () => {
    const now = Date.now();
    const FOUR_HOURS = 4 * 60 * 60 * 1000;
    let count = 0;

    for (const [id, data] of activeProjects.entries()) {
        if (now - (data.lastActive || 0) > FOUR_HOURS) {
            activeProjects.delete(id);
            count++;
        }
    }
    console.log(`[StateManager] 🧹 Memory Cleanup: Removed ${count} inactive projects.`);
    return count;
  } */
};