"""Agent 定时任务 CRUD API"""
from __future__ import annotations

import logging
from datetime import datetime
from typing import Any, Dict, List, Optional

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field
from sqlalchemy.orm import Session

from app.api.auth import get_current_user
from app.core.database import get_db
from app.models.agent import Agent
from app.models.agent_schedule import AgentSchedule
from app.models.user import User
from app.services.agent_schedule_service import (
    compute_next_run,
    create_execution_for_schedule,
)

logger = logging.getLogger(__name__)
router = APIRouter(prefix="/api/v1/agent-schedules", tags=["agent-schedules"])


# ─── Pydantic Schemas ──────────────────────────────────────────────


class ScheduleCreate(BaseModel):
    agent_id: str
    name: str = Field(..., max_length=100)
    cron_expression: str = Field(..., description="标准 5 位 cron，如 0 9 * * *")
    input_message: str = Field(..., description="每次触发时发给 Agent 的消息")
    timezone: str = "Asia/Shanghai"


class ScheduleUpdate(BaseModel):
    name: Optional[str] = None
    cron_expression: Optional[str] = None
    input_message: Optional[str] = None
    timezone: Optional[str] = None
    enabled: Optional[bool] = None


class ScheduleResponse(BaseModel):
    id: str
    agent_id: str
    name: str
    cron_expression: str
    input_message: str
    timezone: str
    enabled: bool
    last_run_at: Optional[datetime] = None
    last_run_status: Optional[str] = None
    next_run_at: datetime
    created_at: datetime
    updated_at: datetime

    class Config:
        from_attributes = True


# ─── API Endpoints ─────────────────────────────────────────────────


@router.get("", response_model=List[ScheduleResponse])
async def list_schedules(
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """获取当前用户的所有定时任务。"""
    schedules = (
        db.query(AgentSchedule)
        .filter(AgentSchedule.user_id == current_user.id)
        .order_by(AgentSchedule.created_at.desc())
        .all()
    )
    return schedules


@router.post("", response_model=ScheduleResponse, status_code=201)
async def create_schedule(
    data: ScheduleCreate,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """创建定时任务。"""
    # 验证 Agent 存在
    agent = db.query(Agent).filter(Agent.id == data.agent_id).first()
    if not agent:
        raise HTTPException(status_code=404, detail="Agent 不存在")
    if agent.user_id and agent.user_id != current_user.id and current_user.role != "admin":
        raise HTTPException(status_code=403, detail="无权使用该 Agent")

    # 验证 cron 表达式
    try:
        next_run = compute_next_run(data.cron_expression)
    except (ValueError, KeyError) as e:
        raise HTTPException(status_code=400, detail=f"cron 表达式无效: {e}")

    schedule = AgentSchedule(
        agent_id=data.agent_id,
        name=data.name,
        cron_expression=data.cron_expression,
        input_message=data.input_message,
        timezone=data.timezone or "Asia/Shanghai",
        enabled=True,
        next_run_at=next_run,
        user_id=current_user.id,
    )
    db.add(schedule)
    db.commit()
    db.refresh(schedule)
    logger.info(
        "定时任务创建: user=%s agent=%s name=%s cron=%s next_run=%s",
        current_user.id, data.agent_id, data.name, data.cron_expression, next_run,
    )
    return schedule


@router.put("/{schedule_id}", response_model=ScheduleResponse)
async def update_schedule(
    schedule_id: str,
    data: ScheduleUpdate,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """更新定时任务配置。"""
    schedule = db.query(AgentSchedule).filter(AgentSchedule.id == schedule_id).first()
    if not schedule:
        raise HTTPException(status_code=404, detail="定时任务不存在")
    if schedule.user_id != current_user.id and current_user.role != "admin":
        raise HTTPException(status_code=403, detail="无权修改该定时任务")

    if data.name is not None:
        schedule.name = data.name
    if data.cron_expression is not None:
        try:
            schedule.next_run_at = compute_next_run(data.cron_expression, after=datetime.utcnow())
            schedule.cron_expression = data.cron_expression
        except (ValueError, KeyError) as e:
            raise HTTPException(status_code=400, detail=f"cron 表达式无效: {e}")
    if data.input_message is not None:
        schedule.input_message = data.input_message
    if data.timezone is not None:
        schedule.timezone = data.timezone
    if data.enabled is not None:
        schedule.enabled = data.enabled

    schedule.updated_at = datetime.utcnow()
    db.commit()
    db.refresh(schedule)
    return schedule


@router.delete("/{schedule_id}")
async def delete_schedule(
    schedule_id: str,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """删除定时任务。"""
    schedule = db.query(AgentSchedule).filter(AgentSchedule.id == schedule_id).first()
    if not schedule:
        raise HTTPException(status_code=404, detail="定时任务不存在")
    if schedule.user_id != current_user.id and current_user.role != "admin":
        raise HTTPException(status_code=403, detail="无权删除该定时任务")

    db.delete(schedule)
    db.commit()
    return {"message": "定时任务已删除"}


@router.post("/{schedule_id}/trigger")
async def trigger_schedule(
    schedule_id: str,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """手动触发一次定时任务。"""
    schedule = db.query(AgentSchedule).filter(AgentSchedule.id == schedule_id).first()
    if not schedule:
        raise HTTPException(status_code=404, detail="定时任务不存在")
    if schedule.user_id != current_user.id and current_user.role != "admin":
        raise HTTPException(status_code=403, detail="无权触发该定时任务")

    execution_id = create_execution_for_schedule(db, schedule)
    if not execution_id:
        raise HTTPException(status_code=500, detail="触发执行失败")

    return {
        "message": "定时任务已触发",
        "execution_id": execution_id,
    }