"""Real-ESRGAN API application."""
import logging
import os
import sys
from contextlib import asynccontextmanager

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

# Ensure app is importable
_app_path = os.path.dirname(__file__)
if _app_path not in sys.path:
    sys.path.insert(0, _app_path)

from app.routers import health, models, upscale
from app.services import file_manager, realesrgan_bridge, worker

logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s %(levelname)s %(name)s: %(message)s'
)
logger = logging.getLogger(__name__)


def _process_upscale_job(job) -> None:
    """Worker function to process upscaling jobs."""
    from app.services import realesrgan_bridge
    
    bridge = realesrgan_bridge.get_bridge()
    success, message, _ = bridge.upscale(
        input_path=job.input_path,
        output_path=job.output_path,
        model_name=job.model,
        outscale=job.outscale,
    )
    
    if not success:
        raise Exception(message)


@asynccontextmanager
async def lifespan(app: FastAPI):
    """Application lifecycle manager."""
    # Startup
    logger.info('Starting Real-ESRGAN API...')
    file_manager.ensure_directories()
    
    bridge = realesrgan_bridge.get_bridge()
    if not bridge.initialize():
        logger.warning('Real-ESRGAN initialization failed (will attempt on first use)')
    
    wq = worker.get_worker_queue(_process_upscale_job, num_workers=2)
    wq.start()
    
    logger.info('Real-ESRGAN API ready')
    yield
    
    # Shutdown
    logger.info('Shutting down Real-ESRGAN API...')
    wq.stop()
    logger.info('Real-ESRGAN API stopped')


app = FastAPI(
    title='Real-ESRGAN API',
    version='1.0.0',
    description='REST API for Real-ESRGAN image upscaling with async job processing',
    lifespan=lifespan,
)

# CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=['*'],
    allow_credentials=True,
    allow_methods=['*'],
    allow_headers=['*'],
)

# Include routers
app.include_router(health.router)
app.include_router(models.router)
app.include_router(upscale.router)


@app.get('/')
async def root():
    """API root endpoint."""
    return {
        'name': 'Real-ESRGAN API',
        'version': '1.0.0',
        'docs': '/docs',
        'redoc': '/redoc',
        'endpoints': {
            'health': '/api/v1/health',
            'system': '/api/v1/system',
            'models': '/api/v1/models',
            'upscale': '/api/v1/upscale',
            'jobs': '/api/v1/jobs',
        },
    }


if __name__ == '__main__':
    import uvicorn
    uvicorn.run(
        'app.main:app',
        host='0.0.0.0',
        port=8000,
        reload=False,
    )