function CourseGa(bookingForm, option) {
    this.bookingForm = bookingForm;
    this.option = option;
    this.data = {};

    // this.onClickSubmit = this.onClickSubmit.bind(this);
    this.onFormSubmit = this.onFormSubmit.bind(this);

    // document.getElementById('btn-submit').addEventListener('click', this.onClickSubmit);
    document.getElementById(this.bookingForm.id).addEventListener('submit', this.onFormSubmit);
}

/* CourseGa.prototype.onClickSubmit = function (evt) {
    // this.data = this.setGaData();
    window.dataLayer = window.dataLayer || [];
    window.dataLayer.push({ ecommerce: null });
    window.dataLayer.push({
        event: "purchase", // Event name
        // ecommerce: this.data,
        ecommerce: this.setGaData()
    });
} */

CourseGa.prototype.onFormSubmit = function (evt) {
    window.dataLayer = window.dataLayer || [];
    window.dataLayer.push({ ecommerce: null });
    window.dataLayer.push({
        event: "purchase", // Event name
        // ecommerce: this.data,
        ecommerce: this.setGaData()
    });
}

CourseGa.prototype.setGaData = function () {
    this.data = {
        transaction_id: courseTransactionId(), // Randomized unique transaction ID
        value: this.bookingForm.price["total"], // Total value including all deltakere
        currency: this.option.currency, // Monetary currency
        items: [
            {
                item_name: courseType(), // Course name
                coupon: courseVoucher(), // Voucher/Coupon string
                currency: this.option.currency, // Monetary currency
                discount: this.bookingForm.price["coupon"], // Monetary value of discount
                item_brand: this.option.brand, // Static
                price: this.bookingForm.price["person"], // Value of 1 item/course (1 deltaker)
                quantity: this.bookingForm.participantCount() // Numerical amount of deltakere
            },
        ]
    };
    
    return this.data;
}