from flask import Flask, request, jsonify
from flask_sqlalchemy import SQLAlchemy
from flask_cors import CORS

app = Flask(__name__)
CORS(app, resources={r"/*": {"origins": "*"}})

app.config['SQLALCHEMY_DATABASE_URI'] = 'postgresql://postgres:yourpassword@postgres-service:5432/calculator'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

db = SQLAlchemy(app)

class Calculation(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    expression = db.Column(db.String(100))
    result = db.Column(db.String(100))

with app.app_context():
    db.create_all()

@app.route('/save', methods=['POST'])
def save_calc():
    data = request.json
    calc = Calculation(expression=data['expression'], result=data['result'])
    db.session.add(calc)
    db.session.commit()
    return jsonify({'message': 'Saved'}), 201

@app.route('/history', methods=['GET'])
def history():
    calcs = Calculation.query.all()
    return jsonify([{'expression': c.expression, 'result': c.result} for c in calcs])

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)