import uuid
import logging
from datetime import datetime
from typing import List, Optional, Dict, Any
from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy import select, desc
from sqlalchemy.ext.asyncio import AsyncSession

from app.database.postgres import get_db, AgentRun, Email, User
from app.database.mongo import mongo_db
from app.auth.security import get_current_user
from app.tasks.email_tasks import fetch_emails_task
from pydantic import BaseModel

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

class AgentRunListItem(BaseModel):
    id: str
    action_type: str
    status: str
    started_at: str
    completed_at: Optional[str] = None
    email_subject: Optional[str] = None
    email_id: Optional[str] = None

class AgentLogItem(BaseModel):
    step: int
    thought: str
    action: str
    result: str
    timestamp: str

@router.post("/trigger-sync")
async def trigger_sync(current_user: User = Depends(get_current_user)):
    """Manually trigger the email synchronization task in the background."""
    task = fetch_emails_task.delay()
    return {"status": "triggered", "task_id": task.id}

@router.get("/runs", response_model=List[AgentRunListItem])
async def list_agent_runs(
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user)
):
    """Retrieve history of agent executions, joining email subjects where applicable."""
    # Custom join to fetch email subject
    query = (
        select(AgentRun, Email.subject)
        .outerjoin(Email, AgentRun.email_id == Email.id)
        .where(AgentRun.user_id == current_user.id)
        .order_by(desc(AgentRun.started_at))
        .limit(30)
    )
    
    result = await db.execute(query)
    rows = result.all()
    
    runs = []
    for row in rows:
        run_obj, email_subj = row
        runs.append(
            AgentRunListItem(
                id=str(run_obj.id),
                action_type=run_obj.action_type,
                status=run_obj.status,
                started_at=run_obj.started_at.isoformat(),
                completed_at=run_obj.completed_at.isoformat() if run_obj.completed_at else None,
                email_subject=email_subj,
                email_id=str(run_obj.email_id) if run_obj.email_id else None
            )
        )
    return runs

@router.get("/runs/{run_id}/logs", response_model=List[AgentLogItem])
async def get_run_logs(
    run_id: str,
    current_user: User = Depends(get_current_user)
):
    """Retrieve step-by-step logic and thoughts of the AI agent from MongoDB."""
    # Ensure MongoDB client connection
    if mongo_db.db is None:
        mongo_db.connect()

    try:
        # Fetch logs for the run, ordered by step
        cursor = mongo_db.agent_logs.find({"run_id": run_id}).sort("step", 1)
        logs = await cursor.to_list(length=100)
        
        return [
            AgentLogItem(
                step=log.get("step", 0),
                thought=log.get("thought", ""),
                action=log.get("action", ""),
                result=log.get("result", ""),
                timestamp=log.get("timestamp", datetime.utcnow()).isoformat()
            )
            for log in logs
        ]
    except Exception as e:
        logger.error(f"Error fetching agent logs: {e}")
        raise HTTPException(status_code=500, detail="Failed to fetch execution logs")