from datetime import datetime
from uuid import uuid4

from sqlalchemy import DateTime, ForeignKey, Integer, String, Text, UniqueConstraint
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.core.database import Base
from app.core.utils.time import utc_now
from app.modules.feishu_users.models import FeishuUser
from app.modules.personalization.constants import (
    CONVERSATION_CODE_PREFIX,
    PREFERENCE_CODE_PREFIX,
    PreferenceSource,
)


def _public_code(prefix: str) -> str:
    return f"{prefix}-{uuid4().hex}"


class UserPreference(Base):
    __tablename__ = "user_preferences"
    __table_args__ = (
        UniqueConstraint(
            "owner_id",
            "category",
            "normalized_value",
            name="uq_user_preference_owner_category_value",
        ),
    )

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    code: Mapped[str] = mapped_column(
        String(64),
        default=lambda: _public_code(PREFERENCE_CODE_PREFIX),
        unique=True,
        index=True,
    )
    owner_id: Mapped[int] = mapped_column(
        ForeignKey("feishu_users.id", ondelete="CASCADE"),
        index=True,
    )
    owner: Mapped[FeishuUser] = relationship()
    category: Mapped[str] = mapped_column(String(32), index=True)
    value: Mapped[str] = mapped_column(Text)
    normalized_value: Mapped[str] = mapped_column(String(1000))
    source: Mapped[str] = mapped_column(
        String(32),
        default=PreferenceSource.EXPLICIT,
        index=True,
    )
    created_at: Mapped[datetime] = mapped_column(DateTime, default=utc_now, index=True)
    updated_at: Mapped[datetime] = mapped_column(
        DateTime,
        default=utc_now,
        onupdate=utc_now,
    )


class AIConversation(Base):
    __tablename__ = "ai_conversations"
    __table_args__ = (
        UniqueConstraint(
            "owner_id",
            "chat_type",
            "chat_key",
            name="uq_ai_conversation_owner_chat",
        ),
    )

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    code: Mapped[str] = mapped_column(
        String(64),
        default=lambda: _public_code(CONVERSATION_CODE_PREFIX),
        unique=True,
        index=True,
    )
    owner_id: Mapped[int] = mapped_column(
        ForeignKey("feishu_users.id", ondelete="CASCADE"),
        index=True,
    )
    owner: Mapped[FeishuUser] = relationship()
    chat_type: Mapped[str] = mapped_column(String(32), index=True)
    chat_key: Mapped[str] = mapped_column(String(256), index=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=utc_now, index=True)
    updated_at: Mapped[datetime] = mapped_column(
        DateTime,
        default=utc_now,
        onupdate=utc_now,
        index=True,
    )
    messages: Mapped[list["AIConversationMessage"]] = relationship(
        back_populates="conversation",
        cascade="all, delete-orphan",
        passive_deletes=True,
        order_by="AIConversationMessage.id",
    )


class AIConversationMessage(Base):
    __tablename__ = "ai_conversation_messages"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    conversation_id: Mapped[int] = mapped_column(
        ForeignKey("ai_conversations.id", ondelete="CASCADE"),
        index=True,
    )
    role: Mapped[str] = mapped_column(String(32), index=True)
    content: Mapped[str] = mapped_column(Text)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=utc_now, index=True)
    conversation: Mapped[AIConversation] = relationship(back_populates="messages")


class PersonalDataErasureRequest(Base):
    __tablename__ = "personal_data_erasure_requests"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    owner_id: Mapped[int] = mapped_column(
        ForeignKey("feishu_users.id", ondelete="CASCADE"),
        unique=True,
        index=True,
    )
    owner: Mapped[FeishuUser] = relationship()
    token_hash: Mapped[str] = mapped_column(String(64))
    expires_at: Mapped[datetime] = mapped_column(DateTime, index=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=utc_now, index=True)
    updated_at: Mapped[datetime] = mapped_column(
        DateTime,
        default=utc_now,
        onupdate=utc_now,
    )