"""SQLAlchemy 数据模型"""
from datetime import datetime
from sqlalchemy import Column, Integer, String, Text, Boolean, DateTime, ForeignKey
from sqlalchemy.orm import relationship
from database import Base


class Feed(Base):
    """RSS 源"""
    __tablename__ = "feeds"

    id = Column(Integer, primary_key=True, index=True)
    url = Column(String(2048), unique=True, nullable=False, index=True)
    title = Column(String(512), default="")
    description = Column(Text, default="")
    category = Column(String(128), default="")
    is_active = Column(Boolean, default=True, index=True)
    fetch_interval_minutes = Column(Integer, default=60)

    # 抓取统计
    last_fetch_at = Column(DateTime, nullable=True)
    last_fetch_status = Column(String(20), default="")
    last_error = Column(Text, default="")
    success_count = Column(Integer, default=0)
    fail_count = Column(Integer, default=0)
    article_count = Column(Integer, default=0)

    created_at = Column(DateTime, default=datetime.utcnow)

    # 关联
    articles = relationship("Article", back_populates="feed", cascade="all, delete-orphan")
    fetch_logs = relationship("FetchLog", back_populates="feed", cascade="all, delete-orphan")

    def health_status(self):
        """计算健康度
        🟢 健康: 成功率 >= 90%, 最近7天有更新
        🟡 警告: 成功率 50%-90%, 或超过3天未更新
        🔴 异常: 成功率 < 50%, 或超过7天未更新
        """
        total = self.success_count + self.fail_count
        if total == 0:
            return "unknown"

        success_rate = self.success_count / total

        days_since_last_fetch = None
        if self.last_fetch_at:
            days_since_last_fetch = (datetime.utcnow() - self.last_fetch_at).days

        if success_rate >= 0.9 and (days_since_last_fetch is None or days_since_last_fetch <= 7):
            return "healthy"
        elif success_rate >= 0.5 and (days_since_last_fetch is None or days_since_last_fetch <= 7):
            return "warning"
        else:
            return "unhealthy"


class Article(Base):
    """RSS 文章"""
    __tablename__ = "articles"

    id = Column(Integer, primary_key=True, index=True)
    feed_id = Column(Integer, ForeignKey("feeds.id", ondelete="CASCADE"), nullable=False, index=True)
    title = Column(String(1024), default="", index=True)
    link = Column(String(2048), unique=True, nullable=False, index=True)
    author = Column(String(256), default="")
    published_at = Column(DateTime, nullable=True, index=True)
    content = Column(Text, default="")
    summary = Column(Text, default="")
    is_read = Column(Boolean, default=False)
    created_at = Column(DateTime, default=datetime.utcnow, index=True)

    # 关联
    feed = relationship("Feed", back_populates="articles")


class FetchLog(Base):
    """抓取日志"""
    __tablename__ = "fetch_logs"

    id = Column(Integer, primary_key=True, index=True)
    feed_id = Column(Integer, ForeignKey("feeds.id", ondelete="CASCADE"), nullable=False, index=True)
    status = Column(String(20), nullable=False)  # success / fail
    articles_fetched = Column(Integer, default=0)
    error_message = Column(Text, default="")
    response_time_ms = Column(Integer, nullable=True)
    created_at = Column(DateTime, default=datetime.utcnow, index=True)

    # 关联
    feed = relationship("Feed", back_populates="fetch_logs")