from sqlalchemy import Column, Integer, String, DateTime, ForeignKey, Enum, Index, Text
from sqlalchemy.sql import func
from app.db.base import Base
import enum

class CampaignStatus(str, enum.Enum):
    DRAFT = "draft"
    SCHEDULED = "scheduled"
    SENDING = "sending"
    DONE = "done"
    FAILED = "failed"

class RecipientStatus(str, enum.Enum):
    PENDING = "pending"
    SENT = "sent"
    DELIVERED = "delivered"
    READ = "read"
    FAILED = "failed"

class Campaign(Base):
    __tablename__ = "campaigns"

    id = Column(Integer, primary_key=True, index=True)
    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True)
    name = Column(String, nullable=False)
    template_id = Column(Integer, ForeignKey("templates.id", ondelete="SET NULL"), nullable=True)
    list_id = Column(Integer, ForeignKey("lists.id", ondelete="SET NULL"), nullable=True)
    status = Column(Enum(CampaignStatus), default=CampaignStatus.DRAFT, nullable=False, index=True)
    scheduled_at = Column(DateTime(timezone=True), nullable=True)
    created_at = Column(DateTime(timezone=True), server_default=func.now())

class CampaignRecipient(Base):
    __tablename__ = "campaign_recipients"
    __table_args__ = (
        Index('ix_campaign_recipients_campaign_status', 'campaign_id', 'status'),
    )

    id = Column(Integer, primary_key=True, index=True)
    campaign_id = Column(Integer, ForeignKey("campaigns.id", ondelete="CASCADE"), nullable=False, index=True)
    contact_id = Column(Integer, ForeignKey("contacts.id", ondelete="CASCADE"), nullable=False, index=True)
    status = Column(Enum(RecipientStatus), default=RecipientStatus.PENDING, nullable=False)
    provider_message_id = Column(String, nullable=True)
    last_error = Column(Text, nullable=True)
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())