# ============================================================================
#  🚀 AI TEST CASE GENERATOR API
#  FastAPI + Groq + PM Tool Integration
#  MVC Architecture Implementation
# ============================================================================

import os
import traceback
from contextlib import asynccontextmanager
from datetime import datetime

from fastapi import FastAPI, HTTPException
from fastapi.responses import JSONResponse
from fastapi.middleware.cors import CORSMiddleware

# Third-party imports
try:
    from groq import Groq
    import pandas as pd
    from openpyxl import Workbook
    from openpyxl.styles import Font, PatternFill, Alignment
except ImportError as e:
    print(f"⚠️  Missing dependency: {e}")
    print("Run: pip install groq pandas openpyxl aiohttp python-jose[cryptography]")
    exit(1)

from app.config import Config
from app.models.schemas import ErrorResponse
from app.views.routes import router
from app.utils.logger import logger
from app.utils.http_client import http_client


# ============================================================================
#  FASTAPI APP INITIALIZATION
# ============================================================================

@asynccontextmanager
async def lifespan(app: FastAPI):
    """Startup and shutdown events"""
    # Startup
    logger.info("🚀 Starting AI Test Case Generator API...")
    await http_client.start()
    
    # Validate Groq API key
    if not Config.GROQ_API_KEY:
        logger.error("❌ GROQ_API_KEY not set! Set it via environment variable.")
    else:
        logger.info("✅ Groq API key configured")
    
    yield
    
    # Shutdown
    logger.info("🛑 Shutting down API...")
    await http_client.close()


app = FastAPI(
    title=Config.API_TITLE,
    version=Config.API_VERSION,
    description=Config.API_DESCRIPTION,
    lifespan=lifespan
)

# CORS Middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Configure appropriately for production
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Include API routes
app.include_router(router)


# ============================================================================
#  EXCEPTION HANDLERS
# ============================================================================

@app.exception_handler(HTTPException)
async def http_exception_handler(request, exc):
    return JSONResponse(
        status_code=exc.status_code,
        content=ErrorResponse(
            error=exc.detail,
            message=str(exc),
            timestamp=datetime.now().isoformat()
        ).dict()
    )


@app.exception_handler(Exception)
async def general_exception_handler(request, exc):
    logger.error(f"Unhandled exception: {exc}\n{traceback.format_exc()}")
    return JSONResponse(
        status_code=500,
        content=ErrorResponse(
            error="Internal Server Error",
            message=str(exc),
            details={"traceback": traceback.format_exc()},
            timestamp=datetime.now().isoformat()
        ).dict()
    )


# ============================================================================
#  MAIN ENTRY POINT
# ============================================================================

if __name__ == "__main__":
    import uvicorn
    
    # Configuration
    HOST = os.getenv("HOST", "0.0.0.0")
    PORT = int(os.getenv("PORT", 8000))
    WORKERS = int(os.getenv("WORKERS", 1))
    
    logger.info(f"""
╔══════════════════════════════════════════════════════════════╗
║  🚀 AI TEST CASE GENERATOR API                              ║
║  Version: {Config.API_VERSION}                                           ║
║  Starting on http://{HOST}:{PORT}                          ║
║  Docs: http://{HOST}:{PORT}/docs                           ║
╚══════════════════════════════════════════════════════════════╝
    """)
    
    uvicorn.run(
        "main:app",
        host=HOST,
        port=PORT,
        workers=WORKERS,
        log_level=Config.LOG_LEVEL.lower(),
        access_log=True
    )