"""数据模型"""
from __future__ import annotations
import uuid
from datetime import datetime
from sqlalchemy import Column, String, Text, Float, Integer, DateTime, ForeignKey, JSON, Boolean
from sqlalchemy.orm import relationship
from .database import Base


class Agent(Base):
    """Agent 定义"""
    __tablename__ = "agents"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    name = Column(String(255), nullable=False)
    description = Column(Text, nullable=True)
    system_prompt = Column(Text, nullable=True)
    llm_provider = Column(String(100), nullable=True)
    temperature = Column(Float, default=0.7)
    max_tokens = Column(Integer, default=2048)
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    tools = relationship("AgentTool", back_populates="agent", cascade="all, delete-orphan")
    conversations = relationship("Conversation", back_populates="agent", cascade="all, delete-orphan")

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


class AgentTool(Base):
    """Agent 绑定的工具"""
    __tablename__ = "agent_tools"

    id = Column(Integer, primary_key=True, autoincrement=True)
    agent_id = Column(String(36), ForeignKey("agents.id", ondelete="CASCADE"), nullable=False)
    tool_name = Column(String(255), nullable=False)
    enabled = Column(Boolean, default=True)

    agent = relationship("Agent", back_populates="tools")

    def __repr__(self) -> str:
        return f"<AgentTool(id={self.id}, agent_id={self.agent_id}, tool_name={self.tool_name!r})>"


class Conversation(Base):
    """对话会话"""
    __tablename__ = "conversations"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    agent_id = Column(String(36), ForeignKey("agents.id", ondelete="CASCADE"), nullable=False)
    title = Column(String(255), nullable=True)
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    agent = relationship("Agent", back_populates="conversations")
    messages = relationship("Message", back_populates="conversation", cascade="all, delete-orphan")

    def __repr__(self) -> str:
        return f"<Conversation(id={self.id}, agent_id={self.agent_id}, title={self.title!r})>"


class Message(Base):
    """消息记录"""
    __tablename__ = "messages"

    id = Column(Integer, primary_key=True, autoincrement=True)
    conversation_id = Column(String(36), ForeignKey("conversations.id", ondelete="CASCADE"), nullable=False)
    role = Column(String(20), nullable=False)  # user / assistant / system / tool
    content = Column(Text, nullable=True)
    tool_calls = Column(JSON, nullable=True)
    created_at = Column(DateTime, default=datetime.utcnow)

    conversation = relationship("Conversation", back_populates="messages")

    def __repr__(self) -> str:
        return f"<Message(id={self.id}, conversation_id={self.conversation_id}, role={self.role!r})>"


class Workflow(Base):
    """工作流定义"""
    __tablename__ = "workflows"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    name = Column(String(255), nullable=False)
    description = Column(Text, nullable=True)
    definition = Column(JSON, nullable=True)
    status = Column(String(50), default="draft")  # draft / active / archived
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    runs = relationship("WorkflowRun", back_populates="workflow", cascade="all, delete-orphan")

    def __repr__(self) -> str:
        return f"<Workflow(id={self.id}, name={self.name!r}, status={self.status!r})>"


class WorkflowRun(Base):
    """工作流执行实例"""
    __tablename__ = "workflow_runs"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    workflow_id = Column(String(36), ForeignKey("workflows.id", ondelete="CASCADE"), nullable=False)
    status = Column(String(50), default="pending")  # pending / running / completed / failed
    results = Column(JSON, nullable=True)
    error = Column(Text, nullable=True)
    started_at = Column(DateTime, default=datetime.utcnow)
    completed_at = Column(DateTime, nullable=True)

    workflow = relationship("Workflow", back_populates="runs")
    steps = relationship("WorkflowStep", back_populates="run", cascade="all, delete-orphan")

    def __repr__(self) -> str:
        return f"<WorkflowRun(id={self.id}, workflow_id={self.workflow_id}, status={self.status!r})>"


class WorkflowStep(Base):
    """工作流步骤"""
    __tablename__ = "workflow_steps"

    id = Column(Integer, primary_key=True, autoincrement=True)
    run_id = Column(String(36), ForeignKey("workflow_runs.id", ondelete="CASCADE"), nullable=False)
    step_name = Column(String(255), nullable=False)
    agent_id = Column(String(36), ForeignKey("agents.id"), nullable=True)
    status = Column(String(50), default="pending")  # pending / running / completed / failed
    input_data = Column(JSON, nullable=True)
    output_data = Column(JSON, nullable=True)
    started_at = Column(DateTime, default=datetime.utcnow)
    completed_at = Column(DateTime, nullable=True)

    run = relationship("WorkflowRun", back_populates="steps")
    agent = relationship("Agent")

    def __repr__(self) -> str:
        return f"<WorkflowStep(id={self.id}, run_id={self.run_id}, step_name={self.step_name!r})>"