"""
FastAPI application for MyDocManager file processor service.

This service provides API endpoints for health checks and task dispatching.
"""

import os
from fastapi import FastAPI, HTTPException
from pydantic import BaseModel
import redis
from celery import Celery

from database.connection import test_database_connection

# Initialize FastAPI app
app = FastAPI(
  title="MyDocManager File Processor",
  description="File processing and task dispatch service",
  version="1.0.0"
)

# Environment variables
REDIS_URL = os.getenv("REDIS_URL", "redis://localhost:6379/0")
MONGODB_URL = os.getenv("MONGODB_URL", "mongodb://localhost:27017")

# Initialize Redis client
try:
  redis_client = redis.from_url(REDIS_URL)
except Exception as e:
  redis_client = None
  print(f"Warning: Could not connect to Redis: {e}")

# Initialize Celery
celery_app = Celery(
  "file_processor",
  broker=REDIS_URL,
  backend=REDIS_URL
)


# Pydantic models
class TestTaskRequest(BaseModel):
  """Request model for test task."""
  message: str


@app.get("/health")
async def health_check():
  """
  Health check endpoint.

  Returns:
      dict: Service health status with dependencies
  """
  health_status = {
      "status": "healthy",
      "service": "file-processor",
      "dependencies": {
          "redis": "unknown",
          "mongodb": "unknown"
      },
  }
  
  # Check Redis connection
  if redis_client:
    try:
      redis_client.ping()
      health_status["dependencies"]["redis"] = "connected"
    except Exception:
      health_status["dependencies"]["redis"] = "disconnected"
      health_status["status"] = "degraded"
  
  # check MongoDB connection
  if test_database_connection():
    health_status["dependencies"]["mongodb"] = "connected"
  else:
    health_status["dependencies"]["mongodb"] = "disconnected"
  
  return health_status


@app.post("/test-task")
async def dispatch_test_task(request: TestTaskRequest):
  """
  Dispatch a test task to Celery worker.

  Args:
      request: Test task request containing message

  Returns:
      dict: Task dispatch information

  Raises:
      HTTPException: If task dispatch fails
  """
  try:
    # Send task to worker
    task = celery_app.send_task(
      "main.test_task",
      args=[request.message]
    )
    
    return {
        "status": "dispatched",
        "task_id": task.id,
        "message": f"Test task dispatched with message: {request.message}"
    }
  
  except Exception as e:
    raise HTTPException(
      status_code=500,
      detail=f"Failed to dispatch task: {str(e)}"
    )


@app.get("/")
async def root():
  """
  Root endpoint.

  Returns:
      dict: Basic service information
  """
  return {
      "service": "MyDocManager File Processor",
      "version": "1.0.0",
      "status": "running"
  }