"""SQLAlchemy 数据模型"""
from datetime import datetime
from sqlalchemy import (
    create_engine, Column, Integer, String, Text, DateTime, LargeBinary,
    Enum as SAEnum, ForeignKey, Table
)
from sqlalchemy.orm import declarative_base, relationship, sessionmaker
from config import get_db_url

engine = create_engine(get_db_url(), echo=False, pool_pre_ping=True)
SessionLocal = sessionmaker(bind=engine, autocommit=False)
Base = declarative_base()


def get_db():
    """获取数据库会话（FastAPI 依赖注入）"""
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()


# ===== 文件夹 =====
class Folder(Base):
    """文件夹表 — 笔记和网站共用"""
    __tablename__ = "folders"

    id = Column(Integer, primary_key=True, autoincrement=True)
    name = Column(String(100), nullable=False)
    type = Column(SAEnum("note", "website", name="folder_type"), nullable=False, default="note")
    parent_id = Column(Integer, ForeignKey("folders.id"), nullable=True)
    sort_order = Column(Integer, default=0)
    created_by = Column(String(100), nullable=False, default="admin")
    created_at = Column(DateTime, default=datetime.utcnow)

    children = relationship("Folder", backref="parent", remote_side=[id])
    notes = relationship("Note", back_populates="folder", cascade="all, delete-orphan")
    websites = relationship("Website", back_populates="folder", cascade="all, delete-orphan")


# ===== 笔记 =====
class Note(Base):
    """笔记表"""
    __tablename__ = "notes"

    id = Column(Integer, primary_key=True, autoincrement=True)
    title = Column(String(500), nullable=False, default="无标题")
    content = Column(Text, nullable=True)  # Tiptap 输出的 HTML
    folder_id = Column(Integer, ForeignKey("folders.id"), nullable=True)
    created_by = Column(String(100), nullable=False, default="admin")
    updated_by = Column(String(100), nullable=False, default="admin")
    share_token = Column(String(64), nullable=True, unique=True)
    share_expires_at = Column(DateTime, nullable=True)
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    folder = relationship("Folder", back_populates="notes")
    tags = relationship("Tag", secondary="note_tags", back_populates="notes")


# ===== 笔记-标签关联 =====
note_tags = Table(
    "note_tags",
    Base.metadata,
    Column("note_id", Integer, ForeignKey("notes.id", ondelete="CASCADE"), primary_key=True),
    Column("tag_id", Integer, ForeignKey("tags.id", ondelete="CASCADE"), primary_key=True),
)


# ===== 标签 =====
class Tag(Base):
    """标签表"""
    __tablename__ = "tags"

    id = Column(Integer, primary_key=True, autoincrement=True)
    name = Column(String(50), nullable=False, unique=True)
    color = Column(String(20), default="#666666")

    notes = relationship("Note", secondary="note_tags", back_populates="tags")


# ===== 网站 =====
class Website(Base):
    """网站表"""
    __tablename__ = "websites"

    id = Column(Integer, primary_key=True, autoincrement=True)
    name = Column(String(200), nullable=False)
    url = Column(String(500), nullable=False)
    folder_id = Column(Integer, ForeignKey("folders.id"), nullable=True)
    created_by = Column(String(100), nullable=False, default="admin")
    updated_by = Column(String(100), nullable=False, default="admin")
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    folder = relationship("Folder", back_populates="websites")
    accounts = relationship("Account", back_populates="website", cascade="all, delete-orphan",
                            order_by="Account.sort_order")


# ===== 账号 =====
class Account(Base):
    """账号表 — 存储网站登录凭据"""
    __tablename__ = "accounts"

    id = Column(Integer, primary_key=True, autoincrement=True)
    website_id = Column(Integer, ForeignKey("websites.id", ondelete="CASCADE"), nullable=False)
    username = Column(String(500), nullable=False)
    password = Column(String(500), nullable=False)  # 明文存储，后续加密
    remark = Column(Text, nullable=True)
    created_by = Column(String(100), nullable=False, default="admin")
    updated_by = Column(String(100), nullable=False, default="admin")
    sort_order = Column(Integer, default=0)
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    website = relationship("Website", back_populates="accounts")


# ===== 上传文件 =====
class Upload(Base):
    """文件上传表 — 图片存储（新文件存文件服务，旧文件兼容 DB blob）"""
    __tablename__ = "uploads"

    id = Column(Integer, primary_key=True, autoincrement=True)
    filename = Column(String(255), nullable=False)
    content_type = Column(String(100), nullable=False)
    data = Column(LargeBinary(length=2**32-1), nullable=True)    # 旧图片 LONGBLOB（兼容），新文件为 NULL
    file_id = Column(String(64), nullable=True)                   # 文件服务返回的 fileId（新文件）
    size = Column(Integer, default=0)
    created_by = Column(String(100), nullable=False, default="admin")
    created_at = Column(DateTime, default=datetime.utcnow)