from sentence_transformers import SentenceTransformer
from flask import Flask, request, jsonify
from flask_cors import CORS # Import CORS

app = Flask(__name__)
CORS(app) # Enable CORS for all routes

# Load the model once when the application starts
# This is efficient as it avoids reloading on every request.
print("Loading sentence-transformer model...")
model = SentenceTransformer('sentence-transformers/all-MiniLM-L6-v2')
print("Model loaded successfully.")

@app.route('/', methods=['GET'])
def health_check():
    """A simple endpoint to check if the service is running."""
    return jsonify({
        'status': 'ok',
        'model': 'sentence-transformers/all-MiniLM-L6-v2'
    })

@app.route('/embed', methods=['POST'])
def embed_text():
    """The main endpoint to generate embeddings."""
    data = request.json
    if not data or 'text' not in data:
        return jsonify({'error': 'No text provided in JSON body'}), 400
    
    text = data.get('text')
    
    if not isinstance(text, str) or not text.strip():
        return jsonify({'error': 'Text must be a non-empty string'}), 400
    
    try:
        # Generate embedding
        embedding = model.encode(text) # No need to wrap in a list for a single string
        
        return jsonify({
            'embedding': embedding.tolist(),
            'model': 'all-MiniLM-L6-v2',
            'dimension': len(embedding)
        })
    except Exception as e:
        print(f"Error during embedding: {e}")
        return jsonify({'error': 'Failed to generate embedding'}), 500