from sqlalchemy import create_engine, Column, Integer, String, ForeignKey, DateTime, Table, MetaData,Text
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship, sessionmaker

Base = declarative_base()
metadata = MetaData()


class File(Base):
    __tablename__ = 'kownledge_file'

    id = Column(Integer, primary_key=True)
    file_identifier = Column(String(50), unique=True, nullable=False, comment='文件唯一标识符')
    file_path = Column(String(255), nullable=False, comment='文件存储路径')
    file_name = Column(String(255), nullable=False, comment='文件名字')
    is_deleted = Column(Integer, default=0, comment='是否删除')

    # 一个文件通过知识库的base_code来关联
    knowledge_base_code = Column(String(50), ForeignKey('knowledge_base.base_code'), nullable=False)
    knowledge_base = relationship("KnowledgeBase", back_populates="files")


class KnowledgeBase(Base):
    __tablename__ = 'knowledge_base'

    # 知识库表主键
    base_id = Column(Integer, primary_key=True)
    # 知识库的基础编码
    base_code = Column(String(50),unique=True, comment='知识库的基础编码')
    # 主题词
    theme_word = Column(String(100), comment='主题词')
    # 事件类型
    event_type = Column(String(100), comment='事件类型')
    # 来源单位
    source_unit = Column(String(100), comment='来源单位')
    # 发布日期
    publish_date = Column(DateTime, comment='发布日期')
    # 知识类型
    knowledge_type = Column(String(100), comment='知识类型')
    # 摘要
    abstract = Column(Text, comment='摘要')
    # 报告名称
    report_name = Column(String(255), comment='报告名称')
    files = relationship("File", order_by=File.id, back_populates="knowledge_base")