from flask import Flask
from flask_cors import CORS, cross_origin
from flask import request

app = Flask(__name__)

# Apply Flask CORS
CORS(app)
app.config['CORS_HEADERS'] = 'Content-Type'

@app.route('/')
@cross_origin(origin='*')
def home():
    return 'Welcome to the Flask Calculator API!'

@app.route('/add', methods=['POST', 'GET'])
@cross_origin(origin='*')
def add_process():
    a = int(request.args.get('a'))
    b = int(request.args.get('b'))
    kq = a + b
    return 'Kết quả là: ' + str(kq)

@app.route('/minus', methods=['POST', 'GET'])
@cross_origin(origin='*')
def minus_process():
    a = int(request.args.get('a'))
    b = int(request.args.get('b'))
    kq = a - b
    return 'Kết quả là: ' + str(kq)

# Start Backend
if __name__ == '__main__':
    app.run(host='0.0.0.0', port='6868')