@app.route("/login", methods=["GET", "POST"])
def login():
    if request.method == "POST":
        email = request.form.get("email")
        password = request.form.get("password")
        print(f"Login attempt with email: {email}")  # Debug log

        try:
            # Fetch user details from Salesforce
            query = f"SELECT Id, Name, Email__c, Reward_Points__c FROM Customer_Login__c WHERE Email__c='{email}' AND Password__c='{password}'"
            result = sf.query(query)

            if result["records"]:
                user = result["records"][0]
                session['user_id'] = user['Id']

                # ✅ Always store or update session email
                if 'user_email' not in session or session['user_email'] != email:
                    session['user_email'] = email
                    session['user_name'] = user.get("Name", "")
                    print(f"✅ Session email updated: {session['user_email']}")

                reward_points = user.get("Reward_Points__c") or 0

                # Coupon generation logic (if reward points >= 500)
                if reward_points >= 500:
                    new_coupon_code = generate_coupon_code()
                    coupon_query = sf.query(f"SELECT Id, Coupon_Code__c FROM Referral_Coupon__c WHERE Referral_Email__c = '{email}'")

                    if coupon_query["records"]:
                        coupon_record = coupon_query["records"][0]
                        referral_coupon_id = coupon_record["Id"]
                        existing_coupons = coupon_record.get("Coupon_Code__c", "")

                        updated_coupons = f"{existing_coupons}\n{new_coupon_code}".strip()
                        sf.Referral_Coupon__c.update(referral_coupon_id, {"Coupon_Code__c": updated_coupons})
                    else:
                        sf.Referral_Coupon__c.create({
                            "Referral_Email__c": email,
                            "Name": user.get("Name", ""),
                            "Coupon_Code__c": new_coupon_code
                        })

                    new_reward_points = reward_points - 500
                    sf.Customer_Login__c.update(user['Id'], {"Reward_Points__c": new_reward_points})

                return redirect(url_for("menu"))

            else:
                print("Invalid credentials!")
                return render_template("login.html", error="Invalid credentials!")

        except Exception as e:
            print(f"Error during login: {str(e)}")
            return render_template("login.html", error=f"Error: {str(e)}")

    return render_template("login.html")