"""
任务实例模型
用于存储任务管理表的数据，记录每次编辑任务的实例
"""
from sqlalchemy import Column, Integer, String, Text, DateTime, Boolean, ForeignKey, JSON, Enum, Index
from sqlalchemy.orm import relationship, foreign
from sqlalchemy.sql.expression import and_
from datetime import datetime
import enum
import uuid
from data.models.base import BaseModel

class TaskInstanceStatus(enum.Enum):
    """任务实例状态枚举"""
    EDITING = "editing"  # 编辑中
    PUBLISHED = "published"  # 已发布

class TaskInstance(BaseModel):
    """任务实例模型"""
    __tablename__ = "task_instances"
    instance_id = Column(String(36), nullable=False, unique=True, index=True, comment="实例唯一ID，用于外部引用")
    task_id = Column(String(50), ForeignKey("tasks.task_id"), nullable=False, comment="关联的任务ID")
    name = Column(String(100), nullable=False, comment="任务名称（复制自任务表）")
    variables = Column(JSON, nullable=True, comment="任务变量")
    priority = Column(Integer, default=1, comment="任务优先级")
    block_outputs = Column(JSON, nullable=True, comment="块输出参数")
    context_params = Column(JSON, nullable=True, comment="上下文参数")
    status = Column(Enum(TaskInstanceStatus), default=TaskInstanceStatus.EDITING, comment="任务实例状态")    
    
    # 确保创建索引
    __table_args__ = (
        Index('idx_task_instances_instance_id', 'instance_id'),
        {'mysql_engine': 'InnoDB'}
    )
    
    # 关联关系 - 使用foreign()显式标记外键
    task = relationship("Task", back_populates="instances")
    input_params = relationship(
        "TaskInputParam", 
        back_populates="instance", 
        primaryjoin="and_(foreign(TaskInstance.instance_id)==TaskInputParam.instance_id, "
                    "TaskInputParam.is_deleted==False)",
        viewonly=False,
        cascade="all"  # 移除delete-orphan级联选项
    )
    
    def __init__(self, **kwargs):
        """初始化实例，自动生成instance_id"""
        if 'instance_id' not in kwargs:
            kwargs['instance_id'] = str(uuid.uuid4())
        super(TaskInstance, self).__init__(**kwargs)
    
    def to_dict(self):
        """转换为字典"""
        return {
            "id": self.instance_id,  # 使用instance_id作为对外ID
            "instance_id": self.instance_id,
            "task_id": self.task_id,
            "name": self.name,
            "variables": self.variables or {},
            "priority": self.priority,
            "block_outputs": self.block_outputs or {},
            "context_params": self.context_params or {},
            "status": self.status.value if self.status else None,
            "created_at": int(self.created_at.timestamp() * 1000) if self.created_at else None,
            "updated_at": int(self.updated_at.timestamp() * 1000) if self.updated_at else None,
            "is_deleted": self.is_deleted
        }
        
    def to_api_dict(self):
        """转换为API响应字典，只返回必要的字段"""
        return {
            "instance_id": self.instance_id,
            "task_id": self.task_id,
            "name": self.name,
            "variables": self.variables or {},
            "priority": self.priority,
            "block_outputs": self.block_outputs or {},
            "context_params": self.context_params or {},
            "status": self.status.value if self.status else None
        }