from flask import Flask, request, jsonify

app = Flask(__name__)

@app.route('/agent/device_summary', methods=['POST'])
def get_device_summary():
    """
    Endpoint to retrieve device statistics based on device IDs and an optional time range.
    """
    data = request.get_json()

    # Validate 'device_ids' parameter
    device_ids = data.get('device_ids')
    if not device_ids or not isinstance(device_ids, list):
        return jsonify({'error': "'device_ids' parameter is required and must be a list"}), 400

    # Validate 'time_range' parameter (optional, defaults to 7)
    time_range = data.get('time_range', 7)
    if not isinstance(time_range, int):
        return jsonify({'error': "'time_range' must be an integer"}), 400

    # Simulate retrieving statistics for the given device IDs and time range
    # In a real application, you would query your database or external service here
    statistics = []
    for device_id in device_ids:
        # Placeholder for actual data retrieval
        stats = {
            'device_id': device_id,
            'time_range': f'Last {time_range} days',
            'data': f'Statistics data for device {device_id} over the last {time_range} days.'
        }
        statistics.append(stats)

    response = {
        'statistics': statistics
    }

    return jsonify(response), 200

if __name__ == '__main__':
    app.run(debug=True)