import os
import uuid
import logging
import random
from pathlib import Path
from flask import Flask, request, jsonify, send_file, render_template
import cv2

from config import Config
from detector import MemoryDetector
from exceptions import DetectionError, FileUploadError, ValidationError, VideoProcessingError
from utils import allowed_file, setup_logging
from video_processor import VideoProcessor

# Initialize Flask app
app = Flask(__name__)
app.config['MAX_CONTENT_LENGTH'] = Config.MAX_FILE_SIZE

# Setup logging
setup_logging()
logger = logging.getLogger(__name__)

# Initialize detector and video processor
detector = None
video_processor = None


def init_app():
    """Initialize application."""
    global detector, video_processor
    
    try:
        # Create directories
        Config.create_directories()
        
        # Validate model exists
        Config.validate_model()
        
        # Initialize detector
        detector = MemoryDetector(
            model_path=Config.MODEL_PATH,
            confidence_threshold=Config.CONFIDENCE_THRESHOLD,
            image_size=Config.IMAGE_SIZE
        )
        
        # Initialize video processor
        video_processor = VideoProcessor(detector)
        
        logger.info("Application initialized successfully")
        
    except Exception as e:
        logger.error(f"Application initialization failed: {e}")
        raise


@app.route('/')
def index():
    """Serve the frontend interface."""
    return render_template('index.html')


@app.route('/api/health')
def health_check():
    """Health check endpoint."""
    return jsonify({
        'status': 'healthy',
        'service': 'Memory Detection API',
        'model_loaded': detector is not None
    })


@app.route('/api/v1/detect', methods=['POST'])
def detect_memory():
    """Detect memory modules in uploaded image."""
    try:
        # Validate file upload
        if 'image' not in request.files:
            raise FileUploadError("No image file provided")
        
        file = request.files['image']
        if file.filename == '':
            raise FileUploadError("No file selected")
        
        if not allowed_file(file.filename, Config.ALLOWED_EXTENSIONS):
            raise ValidationError(f"Invalid file type. Allowed: {Config.ALLOWED_EXTENSIONS}")
        
        # Process image
        logger.info(f"Processing uploaded file: {file.filename}")
        
        # Read image data
        image_bytes = file.read()
        
        # Perform detection
        result = detector.detect_from_bytes(image_bytes)
        
        # Save result image
        filename = f"{uuid.uuid4()}.jpg"
        output_path = Path(Config.RESULT_FOLDER) / filename
        cv2.imwrite(str(output_path), result['annotated_image'])
        
        return jsonify({
            'success': True,
            'data': {
                'detections': result['detections'],
                'detection_count': result['detection_count'],
                'result_image_url': f"/api/v1/results/{filename}"
            }
        })
        
    except (DetectionError, FileUploadError, ValidationError) as e:
        logger.error(f"Detection request failed: {e}")
        return jsonify({
            'success': False,
            'error': str(e)
        }), 400
        
    except Exception as e:
        logger.error(f"Unexpected error in detection: {e}")
        return jsonify({
            'success': False,
            'error': 'Internal server error'
        }), 500


@app.route('/api/v1/results/<filename>')
def get_result_image(filename):
    """Get result image."""
    try:
        file_path = Path(Config.RESULT_FOLDER) / filename
        if not file_path.exists():
            return jsonify({'error': 'Image not found'}), 404
        
        return send_file(file_path)
        
    except Exception as e:
        logger.error(f"Error serving result image: {e}")
        return jsonify({'error': 'Internal server error'}), 500


@app.route('/api/v1/detect/video', methods=['POST'])
def detect_video():
    """Process video for memory module detection."""
    try:
        # Validate video upload
        if 'video' not in request.files:
            raise FileUploadError("No video file provided")
        
        file = request.files['video']
        if file.filename == '':
            raise FileUploadError("No file selected")
        
        # Check video format
        video_extensions = {'mp4', 'avi', 'mov', 'mkv'}
        if not allowed_file(file.filename, video_extensions):
            raise ValidationError(f"Invalid video format. Allowed: {video_extensions}")
        
        # Save uploaded video temporarily
        video_filename = f"temp_{uuid.uuid4()}.mp4"
        video_path = Path(Config.UPLOAD_FOLDER) / video_filename
        file.save(str(video_path))
        
        # Get processing parameters
        fps = request.form.get('fps', 1, type=int)
        max_frames = request.form.get('max_frames', 50, type=int)
        
        logger.info(f"Processing video: {file.filename}, fps={fps}, max_frames={max_frames}")
        
        # Process video
        result = video_processor.process_video(
            str(video_path), 
            fps=fps, 
            max_frames=max_frames
        )
        
        # Clean up temporary file
        video_path.unlink(missing_ok=True)
        
        return jsonify({
            'success': True,
            'data': {
                'video_filename': file.filename,
                'processing_info': result['processing_info'],
                'detections': result['detections'],
                'summary': result['summary']
            }
        })
        
    except (VideoProcessingError, FileUploadError, ValidationError) as e:
        logger.error(f"Video processing failed: {e}")
        return jsonify({
            'success': False,
            'error': str(e)
        }), 400
        
    except Exception as e:
        logger.error(f"Unexpected error in video processing: {e}")
        return jsonify({
            'success': False,
            'error': 'Internal server error'
        }), 500


@app.route('/api/v1/test-images')
def list_test_images():
    """List available test images."""
    try:
        test_images = Config.get_test_images()
        return jsonify({
            'success': True,
            'test_images': [img.name for img in test_images]
        })
        
    except Exception as e:
        logger.error(f"Error listing test images: {e}")
        return jsonify({'error': 'Internal server error'}), 500


@app.errorhandler(413)
def file_too_large(e):
    """Handle file too large error."""
    return jsonify({
        'success': False,
        'error': f'File too large. Maximum size: {Config.MAX_FILE_SIZE} bytes'
    }), 413


if __name__ == '__main__':
    # Initialize application
    init_app()
    
    # Start server
    logger.info(f"Starting server on {Config.HOST}:{Config.PORT}")
    app.run(
        host=Config.HOST,
        port=Config.PORT,
        debug=Config.DEBUG
    )