import uuid
from datetime import datetime
from sqlalchemy import Column, String, Boolean, Integer, DateTime, ForeignKey, UniqueConstraint, LargeBinary
from sqlalchemy.dialects.postgresql import UUID, JSONB
from sqlalchemy.orm import relationship
from pgvector.sqlalchemy import Vector
from app.db import Base

class User(Base):
    __tablename__ = "users"
    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    email = Column(String(320), nullable=False)
    password_hash = Column(String(255), nullable=False)
    role = Column(String(20), nullable=False, default="owner")
    is_active = Column(Boolean, nullable=False, default=True)
    created_at = Column(DateTime(timezone=True), nullable=False, default=datetime.utcnow)

class Hub(Base):
    __tablename__ = "hubs"
    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    owner_id = Column(UUID(as_uuid=True), ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    name = Column(String(120), nullable=False)
    description = Column(String(500), nullable=True)
    ai_summary = Column(String, nullable=True)
    suggested_questions = Column(JSONB, nullable=False, default=list)
    created_at = Column(DateTime(timezone=True), nullable=False, default=datetime.utcnow)
    updated_at = Column(DateTime(timezone=True), nullable=False, default=datetime.utcnow)

    # These relationships belong in Hub, not User!
    documents = relationship("Document", back_populates="hub", cascade="all, delete-orphan")
    chunks = relationship("Chunk", back_populates="hub", cascade="all, delete-orphan")
    
    __table_args__ = (
        UniqueConstraint("owner_id", "name", name="uq_hub_name_per_owner"),
    )

class Document(Base):
    __tablename__ = "documents"
    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    hub_id = Column(UUID(as_uuid=True), ForeignKey("hubs.id", ondelete="CASCADE"), nullable=False)
    owner_id = Column(UUID(as_uuid=True), ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    origin = Column(String(20), nullable=False)
    filename = Column(String(255), nullable=False)
    mime_type = Column(String(100), nullable=False)
    size_bytes = Column(Integer, nullable=False)
    checksum_sha256 = Column(String(64), nullable=False)
    status = Column(String(20), nullable=False, default="pending")
    error_message = Column(String, nullable=True)
    file_bytes = Column(LargeBinary, nullable=True)
    process_claim = Column(UUID(as_uuid=True), nullable=True)
    created_at = Column(DateTime(timezone=True), nullable=False, default=datetime.utcnow)
    updated_at = Column(DateTime(timezone=True), nullable=False, default=datetime.utcnow)

    hub = relationship("Hub", back_populates="documents")

    __table_args__ = (
        UniqueConstraint("hub_id", "checksum_sha256", name="uq_doc_checksum_per_hub"),
    )

class Chunk(Base):
    __tablename__ = "chunks"
    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    document_id = Column(UUID(as_uuid=True), ForeignKey("documents.id", ondelete="CASCADE"), nullable=False)
    hub_id = Column(UUID(as_uuid=True), ForeignKey("hubs.id", ondelete="CASCADE"), nullable=False)
    owner_id = Column(UUID(as_uuid=True), ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    chunk_index = Column(Integer, nullable=False)
    text = Column(String, nullable=False)
    token_count = Column(Integer, nullable=False)
    embedding = Column(Vector(768), nullable=False)
    created_at = Column(DateTime(timezone=True), nullable=False, default=datetime.utcnow)

    hub = relationship("Hub", back_populates="chunks")

class IdempotencyKey(Base):
    __tablename__ = "idempotency_keys"
    user_id = Column(UUID(as_uuid=True), ForeignKey("users.id", ondelete="CASCADE"), primary_key=True)
    key = Column(UUID(as_uuid=True), primary_key=True)
    request_method = Column(String(10), nullable=False)
    request_path = Column(String(255), nullable=False)
    request_hash = Column(String(64), nullable=False)
    status = Column(String(20), nullable=False, default="in_progress")
    response_status = Column(Integer, nullable=True)
    response_body = Column(JSONB, nullable=True)
    created_at = Column(DateTime(timezone=True), nullable=False, default=datetime.utcnow)
    expires_at = Column(DateTime(timezone=True), nullable=False)