from sqlalchemy import Column, String, Boolean, DateTime, Text, Integer, Enum as SQLEnum, create_engine
from sqlalchemy.dialects.postgresql import UUID, JSONB
from sqlalchemy.orm import sessionmaker, declarative_base
import enum
import uuid
from datetime import datetime
from app.config import get_settings

settings = get_settings()
engine = create_engine(settings.DATABASE_URL, pool_pre_ping=True)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
Base = declarative_base()


class TriggerType(str, enum.Enum):
    WELCOME = "welcome"
    KEYWORD = "keyword"
    FALLBACK = "fallback"
    EVENT = "event"
    MANUAL = "manual"


class Flow(Base):
    __tablename__ = "flows"

    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    name = Column(String(100), nullable=False)
    description = Column(Text, nullable=True)
    trigger_type = Column(SQLEnum(TriggerType), nullable=False)
    trigger_value = Column(String(255), nullable=True)
    nodes = Column(JSONB, default=list)
    edges = Column(JSONB, default=list)
    variables = Column(JSONB, default=dict)
    is_active = Column(Boolean, default=False, nullable=False)
    version = Column(Integer, default=1, nullable=False)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    updated_at = Column(DateTime, default=datetime.utcnow, nullable=False)


class FlowSession(Base):
    __tablename__ = "flow_sessions"

    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    conversation_id = Column(UUID(as_uuid=True), nullable=False, index=True)
    flow_id = Column(UUID(as_uuid=True), nullable=False)
    current_node_id = Column(String(100), nullable=True)
    variables = Column(JSONB, default=dict)
    waiting_for_input = Column(Boolean, default=False)
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    updated_at = Column(DateTime, default=datetime.utcnow, nullable=False)


def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()