"""
════════════════════════════════════════════════════════════════════════════
SESSION MEMORY - Sistema de Memória Persistente (PostgreSQL + Skills)
════════════════════════════════════════════════════════════════════════════
✅ Memória persistente entre sessões via PostgreSQL
✅ Isolamento por utilizador + grupo
✅ Extração automática de factos
✅ Checkpoints de conversa
✅ Integração com skills (contexto de ações)
✅ Recuperação inteligente
════════════════════════════════════════════════════════════════════════════
"""

import os
import json
import hashlib
import re
import time
import threading
from datetime import datetime
from typing import Optional, Dict, List, Any
from dataclasses import dataclass, field

# ============================================================
# DATACLASSES
# ============================================================

@dataclass
class MemoryEntry:
    """Uma entrada de memória"""
    key: str
    content: str
    memory_type: str  # "user", "feedback", "project", "reference", "skill"
    timestamp: float = field(default_factory=time.time)
    metadata: Dict[str, Any] = field(default_factory=dict)

@dataclass
class SessionCheckpoint:
    """Checkpoint de uma sessão"""
    session_id: str
    user_id: str
    group_id: Optional[str]
    timestamp: float
    summary: str
    active_topics: List[str]
    key_decisions: List[str]
    unresolved: List[str]
    skills_used: List[str]
    mood: str = "neutral"
    message_count: int = 0

# ============================================================
# GERADOR DE IDs
# ============================================================

def generate_session_id(user_id: str, group_id: Optional[str] = None) -> str:
    """Gera ID único para sessão"""
    now = datetime.now()
    date_str = now.strftime("%Y%m%d")
    raw = f"{user_id}:{group_id or 'pv'}:{date_str}"
    return hashlib.md5(raw.encode()).hexdigest()[:16]

def generate_memory_key(user_id: str, topic: str, group_id: Optional[str] = None) -> str:
    """Gera chave para entrada de memória"""
    raw = f"{user_id}:{group_id or 'pv'}:{topic.lower().strip()}"
    return hashlib.md5(raw.encode()).hexdigest()[:12]

# ============================================================
# SESSION MEMORY - PostgreSQL
# ============================================================

class SessionMemory:
    """Memória persistente via PostgreSQL com isolamento por grupo"""
    
    _instance = None
    _lock = threading.Lock()
    
    def __new__(cls):
        if cls._instance is None:
            with cls._lock:
                if cls._instance is None:
                    cls._instance = super().__new__(cls)
                    cls._instance._initialized = False
        return cls._instance
    
    def __init__(self):
        if self._initialized:
            return
        self._initialized = True
        self._db = None
        self._init_tables()
    
    def _get_db(self):
        """Obtém instância do banco de dados"""
        if self._db is None:
            try:
                from .database_pg import DatabasePG
                self._db = DatabasePG()
            except Exception as e:
                print(f"⚠️ [SESSION MEMORY] DB não disponível: {e}")
                return None
        return self._db
    
    def _init_tables(self):
        """Cria tabelas necessárias no PostgreSQL"""
        db = self._get_db()
        if not db:
            return
        
        try:
            conn = db._get_connection()
            cur = conn.cursor()
            
            # Tabela de memória persistente
            cur.execute("""
                CREATE TABLE IF NOT EXISTS session_memory (
                    id SERIAL PRIMARY KEY,
                    user_id TEXT NOT NULL,
                    group_id TEXT DEFAULT NULL,
                    key TEXT NOT NULL,
                    content TEXT NOT NULL,
                    memory_type TEXT DEFAULT 'reference',
                    timestamp DOUBLE PRECISION DEFAULT 0,
                    metadata JSONB DEFAULT '{}',
                    created_at TIMESTAMP DEFAULT NOW(),
                    UNIQUE(user_id, group_id, key)
                )
            """)
            cur.execute("CREATE INDEX IF NOT EXISTS idx_sm_user ON session_memory(user_id)")
            cur.execute("CREATE INDEX IF NOT EXISTS idx_sm_group ON session_memory(user_id, group_id)")
            cur.execute("CREATE INDEX IF NOT EXISTS idx_sm_type ON session_memory(memory_type)")
            
            # Tabela de checkpoints
            cur.execute("""
                CREATE TABLE IF NOT EXISTS session_checkpoints (
                    id SERIAL PRIMARY KEY,
                    session_id TEXT NOT NULL,
                    user_id TEXT NOT NULL,
                    group_id TEXT DEFAULT NULL,
                    timestamp DOUBLE PRECISION DEFAULT 0,
                    summary TEXT DEFAULT '',
                    active_topics JSONB DEFAULT '[]',
                    key_decisions JSONB DEFAULT '[]',
                    unresolved JSONB DEFAULT '[]',
                    skills_used JSONB DEFAULT '[]',
                    mood TEXT DEFAULT 'neutral',
                    message_count INTEGER DEFAULT 0,
                    created_at TIMESTAMP DEFAULT NOW()
                )
            """)
            cur.execute("CREATE INDEX IF NOT EXISTS idx_sc_user ON session_checkpoints(user_id)")
            cur.execute("CREATE INDEX IF NOT EXISTS idx_sc_group ON session_checkpoints(user_id, group_id)")
            cur.execute("CREATE INDEX IF NOT EXISTS idx_sc_session ON session_checkpoints(session_id)")
            
            # Tabela de skills usage
            cur.execute("""
                CREATE TABLE IF NOT EXISTS session_skills (
                    id SERIAL PRIMARY KEY,
                    user_id TEXT NOT NULL,
                    group_id TEXT DEFAULT NULL,
                    skill_name TEXT NOT NULL,
                    skill_args JSONB DEFAULT '{}',
                    skill_result TEXT DEFAULT '',
                    timestamp DOUBLE PRECISION DEFAULT 0,
                    success BOOLEAN DEFAULT TRUE,
                    created_at TIMESTAMP DEFAULT NOW()
                )
            """)
            cur.execute("CREATE INDEX IF NOT EXISTS idx_ss_user ON session_skills(user_id)")
            cur.execute("CREATE INDEX IF NOT EXISTS idx_ss_skill ON session_skills(skill_name)")
            
            conn.commit()
            conn.close()
            print("✅ [SESSION MEMORY] Tabelas PostgreSQL criadas/garantidas")
            
        except Exception as e:
            print(f"❌ [SESSION MEMORY] Erro ao criar tabelas: {e}")
    
    # ============================================================
    # ESCRITA
    # ============================================================
    
    def add_memory(self, user_id: str, entry: MemoryEntry, group_id: Optional[str] = None) -> bool:
        """Adiciona entrada de memória"""
        db = self._get_db()
        if not db:
            return False
        
        try:
            conn = db._get_connection()
            cur = conn.cursor()
            cur.execute("""
                INSERT INTO session_memory (user_id, group_id, key, content, memory_type, timestamp, metadata)
                VALUES (%s, %s, %s, %s, %s, %s, %s)
                ON CONFLICT (user_id, group_id, key) 
                DO UPDATE SET content = EXCLUDED.content, timestamp = EXCLUDED.timestamp, metadata = EXCLUDED.metadata
            """, (user_id, group_id, entry.key, entry.content, entry.memory_type, entry.timestamp, json.dumps(entry.metadata)))
            conn.commit()
            conn.close()
            return True
        except Exception as e:
            print(f"❌ [SESSION MEMORY] Erro ao adicionar memória: {e}")
            return False
    
    def save_checkpoint(self, checkpoint: SessionCheckpoint) -> bool:
        """Salva checkpoint de sessão"""
        db = self._get_db()
        if not db:
            return False
        
        try:
            conn = db._get_connection()
            cur = conn.cursor()
            cur.execute("""
                INSERT INTO session_checkpoints 
                (session_id, user_id, group_id, timestamp, summary, active_topics, key_decisions, unresolved, skills_used, mood, message_count)
                VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)
            """, (
                checkpoint.session_id, checkpoint.user_id, checkpoint.group_id,
                checkpoint.timestamp, checkpoint.summary,
                json.dumps(checkpoint.active_topics), json.dumps(checkpoint.key_decisions),
                json.dumps(checkpoint.unresolved), json.dumps(checkpoint.skills_used),
                checkpoint.mood, checkpoint.message_count
            ))
            conn.commit()
            conn.close()
            return True
        except Exception as e:
            print(f"❌ [SESSION MEMORY] Erro ao salvar checkpoint: {e}")
            return False
    
    def log_skill_usage(self, user_id: str, group_id: Optional[str], skill_name: str, 
                       skill_args: dict, skill_result: str, success: bool = True) -> bool:
        """Regista uso de uma skill"""
        db = self._get_db()
        if not db:
            return False
        
        try:
            conn = db._get_connection()
            cur = conn.cursor()
            cur.execute("""
                INSERT INTO session_skills (user_id, group_id, skill_name, skill_args, skill_result, timestamp, success)
                VALUES (%s, %s, %s, %s, %s, %s, %s)
            """, (user_id, group_id, skill_name, json.dumps(skill_args), skill_result, time.time(), success))
            conn.commit()
            conn.close()
            return True
        except Exception as e:
            print(f"❌ [SESSION MEMORY] Erro ao registar skill: {e}")
            return False
    
    # ============================================================
    # LEITURA
    # ============================================================
    
    def get_memory(self, user_id: str, group_id: Optional[str] = None, limit: int = 50) -> List[MemoryEntry]:
        """Retorna memória do utilizador/grupo"""
        db = self._get_db()
        if not db:
            return []
        
        try:
            conn = db._get_connection()
            cur = conn.cursor()
            cur.execute("""
                SELECT key, content, memory_type, timestamp, metadata
                FROM session_memory
                WHERE user_id = %s AND (group_id = %s OR (group_id IS NULL AND %s IS NULL))
                ORDER BY timestamp DESC
                LIMIT %s
            """, (user_id, group_id, group_id, limit))
            
            entries = []
            for row in cur.fetchall():
                entries.append(MemoryEntry(
                    key=row[0], content=row[1], memory_type=row[2],
                    timestamp=row[3], metadata=json.loads(row[4]) if row[4] else {}
                ))
            
            conn.close()
            return entries
        except Exception as e:
            print(f"❌ [SESSION MEMORY] Erro ao ler memória: {e}")
            return []
    
    def get_recent_checkpoints(self, user_id: str, group_id: Optional[str] = None, limit: int = 3) -> List[SessionCheckpoint]:
        """Retorna checkpoints recentes"""
        db = self._get_db()
        if not db:
            return []
        
        try:
            conn = db._get_connection()
            cur = conn.cursor()
            cur.execute("""
                SELECT session_id, user_id, group_id, timestamp, summary, 
                       active_topics, key_decisions, unresolved, skills_used, mood, message_count
                FROM session_checkpoints
                WHERE user_id = %s AND (group_id = %s OR (group_id IS NULL AND %s IS NULL))
                ORDER BY timestamp DESC
                LIMIT %s
            """, (user_id, group_id, group_id, limit))
            
            checkpoints = []
            for row in cur.fetchall():
                checkpoints.append(SessionCheckpoint(
                    session_id=row[0], user_id=row[1], group_id=row[2],
                    timestamp=row[3], summary=row[4],
                    active_topics=json.loads(row[5]) if row[5] else [],
                    key_decisions=json.loads(row[6]) if row[6] else [],
                    unresolved=json.loads(row[7]) if row[7] else [],
                    skills_used=json.loads(row[8]) if row[8] else [],
                    mood=row[9], message_count=row[10]
                ))
            
            conn.close()
            return checkpoints
        except Exception as e:
            print(f"❌ [SESSION MEMORY] Erro ao ler checkpoints: {e}")
            return []
    
    def get_recent_skills(self, user_id: str, group_id: Optional[str] = None, limit: int = 10) -> List[Dict]:
        """Retorna skills usadas recentemente"""
        db = self._get_db()
        if not db:
            return []
        
        try:
            conn = db._get_connection()
            cur = conn.cursor()
            cur.execute("""
                SELECT skill_name, skill_args, skill_result, timestamp, success
                FROM session_skills
                WHERE user_id = %s AND (group_id = %s OR (group_id IS NULL AND %s IS NULL))
                ORDER BY timestamp DESC
                LIMIT %s
            """, (user_id, group_id, group_id, limit))
            
            skills = []
            for row in cur.fetchall():
                skills.append({
                    'name': row[0], 'args': json.loads(row[1]) if row[1] else {},
                    'result': row[2], 'timestamp': row[3], 'success': row[4]
                })
            
            conn.close()
            return skills
        except Exception as e:
            print(f"❌ [SESSION MEMORY] Erro ao ler skills: {e}")
            return []
    
    def search_memory(self, user_id: str, query: str, group_id: Optional[str] = None, limit: int = 5) -> List[str]:
        """Busca na memória"""
        db = self._get_db()
        if not db:
            return []
        
        try:
            conn = db._get_connection()
            cur = conn.cursor()
            # Busca por content LIKE
            cur.execute("""
                SELECT content FROM session_memory
                WHERE user_id = %s AND (group_id = %s OR (group_id IS NULL AND %s IS NULL))
                AND content ILIKE %s
                ORDER BY timestamp DESC
                LIMIT %s
            """, (user_id, group_id, group_id, f'%{query}%', limit))
            
            results = [row[0] for row in cur.fetchall()]
            conn.close()
            return results
        except Exception as e:
            print(f"❌ [SESSION MEMORY] Erro na busca: {e}")
            return []
    
    # ============================================================
    # EXTRAÇÃO AUTOMÁTICA
    # ============================================================
    
    def extract_and_store(self, user_id: str, group_id: Optional[str], message: str, 
                         response: str, emotion: str = "neutral", topic: str = "",
                         skills_used: List[str] = None) -> List[MemoryEntry]:
        """Extrai factos importantes e armazena"""
        entries = []
        
        patterns = {
            "preference": [
                r"(?:gosto|adoro|odeio|prefiro|não gosto|não suporto)\s+(?:de\s+)?(.+)",
            ],
            "fact": [
                r"(?:meu|minha|meu)\s+(?:nome|idade|trabalho|casa|escola)\s+(?:é|e|são)\s+(.+)",
            ],
            "decision": [
                r"(?:vamos|decidimos|vou|vai)\s+(?:fazer|comprar|mudar|alterar)\s+(.+)",
            ],
        }
        
        for text in [message, response]:
            if not text:
                continue
            for fact_type, regexes in patterns.items():
                for regex in regexes:
                    matches = re.findall(regex, text, re.IGNORECASE)
                    for match in matches:
                        if len(match) > 5:
                            entry = MemoryEntry(
                                key=generate_memory_key(user_id, match, group_id),
                                content=f"{fact_type}: {match}",
                                memory_type="reference",
                                metadata={"source": "auto_extract", "emotion": emotion, "topic": topic}
                            )
                            self.add_memory(user_id, entry, group_id)
                            entries.append(entry)
        
        return entries
    
    def update_user_summary(self, user_id: str, group_id: Optional[str], summary: str) -> bool:
        """Atualiza resumo do utilizador"""
        entry = MemoryEntry(
            key="user_summary",
            content=summary,
            memory_type="user",
            metadata={"type": "summary"}
        )
        return self.add_memory(user_id, entry, group_id)


# ============================================================
# SESSION MANAGER - Gestor Principal
# ============================================================

class SessionManager:
    """Gestor de sessões com integração PostgreSQL e Skills"""
    
    _instance = None
    _lock = threading.Lock()
    
    def __new__(cls):
        if cls._instance is None:
            with cls._lock:
                if cls._instance is None:
                    cls._instance = super().__new__(cls)
                    cls._instance._initialized = False
        return cls._instance
    
    def __init__(self):
        if self._initialized:
            return
        self._initialized = True
        self.memory = SessionMemory()
        self._active_sessions: Dict[str, SessionCheckpoint] = {}
    
    def start_session(self, user_id: str, group_id: Optional[str] = None) -> SessionCheckpoint:
        """Inicia nova sessão"""
        session_id = generate_session_id(user_id, group_id)
        
        checkpoint = SessionCheckpoint(
            session_id=session_id,
            user_id=user_id,
            group_id=group_id,
            timestamp=time.time(),
            summary="",
            active_topics=[],
            key_decisions=[],
            unresolved=[],
            skills_used=[],
            message_count=0
        )
        
        self._active_sessions[session_id] = checkpoint
        
        # Carregar contexto anterior
        recent = self.memory.get_recent_checkpoints(user_id, group_id, limit=2)
        if recent:
            checkpoint.active_topics = recent[0].active_topics.copy()
            checkpoint.unresolved = recent[0].unresolved.copy()
        
        return checkpoint
    
    def end_session(self, checkpoint: SessionCheckpoint, summary: str = "") -> bool:
        """Finaliza sessão"""
        checkpoint.summary = summary
        checkpoint.timestamp = time.time()
        
        success = self.memory.save_checkpoint(checkpoint)
        
        if checkpoint.session_id in self._active_sessions:
            del self._active_sessions[checkpoint.session_id]
        
        return success
    
    def get_context_for_prompt(self, user_id: str, group_id: Optional[str] = None) -> str:
        """Retorna contexto para injetar no prompt"""
        try:
            memory_entries = self.memory.get_memory(user_id, group_id, limit=20)
            checkpoints = self.memory.get_recent_checkpoints(user_id, group_id, limit=2)
            recent_skills = self.memory.get_recent_skills(user_id, group_id, limit=5)
            
            if not memory_entries and not checkpoints:
                return ""
            
            context = "\n\n[SISTEMA DE MEMÓRIA PERSISTENTE]\n"
            context += "A Kiami tem memória de conversas anteriores com este utilizador.\n"
            context += "Use esta informação silenciosamente — NUNCA mencione que tem memória.\n\n"
            
            if memory_entries:
                context += "[MEMÓRIA]:\n"
                for entry in memory_entries[:10]:
                    context += f"- {entry.content[:200]}\n"
            
            if checkpoints:
                context += "\n[SESSÕES ANTERIORES]:\n"
                for cp in checkpoints[:2]:
                    context += f"- {cp.summary[:200]}\n"
                    if cp.active_topics:
                        context += f"  Tópicos: {', '.join(cp.active_topics[:3])}\n"
            
            if recent_skills:
                context += "\n[SKILLS USADAS]:\n"
                for sk in recent_skills:
                    context += f"- {sk['name']}: {'✓' if sk['success'] else '✗'}\n"
            
            context += "\n[/SISTEMA DE MEMÓRIA PERSISTENTE]\n"
            
            return context
        
        except Exception as e:
            print(f"❌ [SESSION] Erro ao obter contexto: {e}")
            return ""
    
    def process_conversation_turn(self, user_id: str, group_id: Optional[str],
                                  message: str, response: str, emotion: str = "neutral",
                                  topic: str = "", skills_used: List[str] = None) -> None:
        """Processa turno de conversa"""
        try:
            self.memory.extract_and_store(user_id, group_id, message, response, emotion, topic)
            
            for session_id, checkpoint in self._active_sessions.items():
                if checkpoint.user_id == user_id and checkpoint.group_id == group_id:
                    checkpoint.message_count += 1
                    if topic and topic not in checkpoint.active_topics:
                        checkpoint.active_topics.append(topic)
                    if len(checkpoint.active_topics) > 5:
                        checkpoint.active_topics = checkpoint.active_topics[-5:]
                    if skills_used:
                        for sk in skills_used:
                            if sk not in checkpoint.skills_used:
                                checkpoint.skills_used.append(sk)
                    break
        
        except Exception as e:
            print(f"❌ [SESSION] Erro ao processar turno: {e}")
    
    def log_skill(self, user_id: str, group_id: Optional[str], skill_name: str,
                  skill_args: dict, skill_result: str, success: bool = True) -> None:
        """Regista uso de skill"""
        try:
            self.memory.log_skill_usage(user_id, group_id, skill_name, skill_args, skill_result, success)
        except Exception as e:
            print(f"❌ [SESSION] Erro ao registar skill: {e}")


# ============================================================
# INSTÂNCIA GLOBAL
# ============================================================

_session_manager: Optional[SessionManager] = None

def get_session_manager() -> SessionManager:
    global _session_manager
    if _session_manager is None:
        _session_manager = SessionManager()
    return _session_manager