# database/models.py - SQLAlchemy ORM 数据模型
from datetime import datetime
from sqlalchemy import (
    Column, Integer, String, Text, Boolean,
    DateTime, ForeignKey, Enum,
)
from sqlalchemy.orm import declarative_base, relationship

Base = declarative_base()


class Project(Base):
    """项目表"""
    __tablename__ = "projects"

    id          = Column(Integer, primary_key=True, autoincrement=True)
    name        = Column(String(200), nullable=False, unique=True)
    language    = Column(String(50),  nullable=False, default="python")
    description = Column(Text,        nullable=True)
    output_dir  = Column(String(500), nullable=True)
    created_at  = Column(DateTime,    default=datetime.utcnow)
    updated_at  = Column(DateTime,    default=datetime.utcnow, onupdate=datetime.utcnow)

    raw_requirements      = relationship("RawRequirement",      back_populates="project", cascade="all, delete-orphan")
    functional_requirements = relationship("FunctionalRequirement", back_populates="project", cascade="all, delete-orphan")
    change_history = relationship("ChangeHistory", back_populates="project", cascade="all, delete-orphan")

    def __repr__(self):
        return f"<Project(id={self.id}, name={self.name!r}, language={self.language!r})>"


class RawRequirement(Base):
    """原始需求表"""
    __tablename__ = "raw_requirements"

    id          = Column(Integer,     primary_key=True, autoincrement=True)
    project_id  = Column(Integer,     ForeignKey("projects.id"), nullable=False)
    content     = Column(Text,        nullable=False)
    source_type = Column(String(20),  nullable=False, default="text")   # text / file
    source_name = Column(String(200), nullable=True)
    knowledge   = Column(Text,        nullable=True)
    created_at  = Column(DateTime,    default=datetime.utcnow)

    project               = relationship("Project",               back_populates="raw_requirements")
    functional_requirements = relationship("FunctionalRequirement", back_populates="raw_requirement", cascade="all, delete-orphan")

    def __repr__(self):
        return f"<RawRequirement(id={self.id}, project_id={self.project_id})>"


class FunctionalRequirement(Base):
    """功能需求表"""
    __tablename__ = "functional_requirements"

    id            = Column(Integer,    primary_key=True, autoincrement=True)
    project_id    = Column(Integer,    ForeignKey("projects.id"),       nullable=False)
    raw_req_id    = Column(Integer,    ForeignKey("raw_requirements.id"), nullable=False)
    index_no      = Column(Integer,    nullable=False)
    title         = Column(String(200), nullable=False)
    description   = Column(Text,       nullable=False)
    function_name = Column(String(200), nullable=False)
    priority      = Column(Enum("high", "medium", "low"), default="medium")
    module        = Column(String(100), nullable=True,  default="default")  # 功能模块
    status        = Column(String(50),  nullable=False, default="pending")  # pending / generated / failed
    is_custom     = Column(Boolean,     nullable=False, default=False)
    created_at    = Column(DateTime,    default=datetime.utcnow)
    updated_at    = Column(DateTime,    default=datetime.utcnow, onupdate=datetime.utcnow)

    project          = relationship("Project",          back_populates="functional_requirements")
    raw_requirement  = relationship("RawRequirement",   back_populates="functional_requirements")
    code_files       = relationship("CodeFile",         back_populates="functional_requirement", cascade="all, delete-orphan")

    def __repr__(self):
        return (
            f"<FunctionalRequirement(id={self.id}, title={self.title!r}, "
            f"module={self.module!r}, status={self.status!r})>"
        )


class CodeFile(Base):
    """生成代码文件表"""
    __tablename__ = "code_files"

    id               = Column(Integer,    primary_key=True, autoincrement=True)
    func_req_id      = Column(Integer,    ForeignKey("functional_requirements.id"), nullable=False)
    file_name        = Column(String(200), nullable=False)
    file_path        = Column(String(500), nullable=False)
    module           = Column(String(100), nullable=True)   # 冗余存储，方便查询
    language         = Column(String(50),  nullable=False)
    content          = Column(Text,        nullable=True)
    generated_at     = Column(DateTime,    default=datetime.utcnow)

    functional_requirement = relationship("FunctionalRequirement", back_populates="code_files")

    def __repr__(self):
        return f"<CodeFile(id={self.id}, file_name={self.file_name!r}, module={self.module!r})>"


class ChangeHistory(Base):
    """变更历史表"""
    __tablename__ = "change_history"

    id          = Column(Integer, primary_key=True, autoincrement=True)
    project_id  = Column(Integer, ForeignKey("projects.id"), nullable=False)
    change_time = Column(DateTime, default=datetime.utcnow)
    changes     = Column(Text, nullable=False)  # 记录变更内容
    status      = Column(String(50), nullable=False, default="pending")  # pending / confirmed

    project = relationship("Project", back_populates="change_history")

    def __repr__(self):
        return f"<ChangeHistory(id={self.id}, project_id={self.project_id}, changes={self.changes[:20]}...)>"