orion/app/modules/billing/static/vendor/js/billing.js

// app/modules/billing/static/vendor/js/billing.js
// Vendor billing and subscription management

const billingLog = window.LogConfig?.createLogger('BILLING') || console;

function vendorBilling() {
    return {
        // Inherit base data (dark mode, sidebar, vendor info, etc.)
        ...data(),
        currentPage: 'billing',

        // State
        loading: true,
        subscription: null,
        tiers: [],
        addons: [],
        myAddons: [],
        invoices: [],

        // UI state
        showTiersModal: false,
        showAddonsModal: false,
        showCancelModal: false,
        showSuccessMessage: false,
        showCancelMessage: false,
        showAddonSuccessMessage: false,
        cancelReason: '',
        purchasingAddon: null,

        // Initialize
        async init() {
            // Load i18n translations
            await I18n.loadModule('billing');

            // Guard against multiple initialization
            if (window._vendorBillingInitialized) return;
            window._vendorBillingInitialized = true;

            // IMPORTANT: Call parent init first to set vendorCode from URL
            const parentInit = data().init;
            if (parentInit) {
                await parentInit.call(this);
            }

            try {
                // Check URL params for success/cancel
                const params = new URLSearchParams(window.location.search);
                if (params.get('success') === 'true') {
                    this.showSuccessMessage = true;
                    window.history.replaceState({}, document.title, window.location.pathname);
                }
                if (params.get('cancelled') === 'true') {
                    this.showCancelMessage = true;
                    window.history.replaceState({}, document.title, window.location.pathname);
                }
                if (params.get('addon_success') === 'true') {
                    this.showAddonSuccessMessage = true;
                    window.history.replaceState({}, document.title, window.location.pathname);
                }

                await this.loadData();
            } catch (error) {
                billingLog.error('Failed to initialize billing page:', error);
            }
        },

        async loadData() {
            this.loading = true;
            try {
                // Load all data in parallel
                const [subscriptionRes, tiersRes, addonsRes, myAddonsRes, invoicesRes] = await Promise.all([
                    apiClient.get('/vendor/billing/subscription'),
                    apiClient.get('/vendor/billing/tiers'),
                    apiClient.get('/vendor/billing/addons'),
                    apiClient.get('/vendor/billing/my-addons'),
                    apiClient.get('/vendor/billing/invoices?limit=5'),
                ]);

                this.subscription = subscriptionRes;
                this.tiers = tiersRes.tiers || [];
                this.addons = addonsRes || [];
                this.myAddons = myAddonsRes || [];
                this.invoices = invoicesRes.invoices || [];

            } catch (error) {
                billingLog.error('Error loading billing data:', error);
                Utils.showToast(I18n.t('billing.messages.failed_to_load_billing_data'), 'error');
            } finally {
                this.loading = false;
            }
        },

        async selectTier(tier) {
            if (tier.is_current) return;

            try {
                const response = await apiClient.post('/vendor/billing/checkout', {
                    tier_code: tier.code,
                    is_annual: false
                });

                if (response.checkout_url) {
                    window.location.href = response.checkout_url;
                }
            } catch (error) {
                billingLog.error('Error creating checkout:', error);
                Utils.showToast(I18n.t('billing.messages.failed_to_create_checkout_session'), 'error');
            }
        },

        async openPortal() {
            try {
                const response = await apiClient.post('/vendor/billing/portal', {});
                if (response.portal_url) {
                    window.location.href = response.portal_url;
                }
            } catch (error) {
                billingLog.error('Error opening portal:', error);
                Utils.showToast(I18n.t('billing.messages.failed_to_open_payment_portal'), 'error');
            }
        },

        async cancelSubscription() {
            try {
                await apiClient.post('/vendor/billing/cancel', {
                    reason: this.cancelReason,
                    immediately: false
                });

                this.showCancelModal = false;
                Utils.showToast(I18n.t('billing.messages.subscription_cancelled_you_have_access_u'), 'success');
                await this.loadData();

            } catch (error) {
                billingLog.error('Error cancelling subscription:', error);
                Utils.showToast(I18n.t('billing.messages.failed_to_cancel_subscription'), 'error');
            }
        },

        async reactivate() {
            try {
                await apiClient.post('/vendor/billing/reactivate', {});
                Utils.showToast(I18n.t('billing.messages.subscription_reactivated'), 'success');
                await this.loadData();

            } catch (error) {
                billingLog.error('Error reactivating subscription:', error);
                Utils.showToast(I18n.t('billing.messages.failed_to_reactivate_subscription'), 'error');
            }
        },

        async purchaseAddon(addon) {
            this.purchasingAddon = addon.code;
            try {
                const response = await apiClient.post('/vendor/billing/addons/purchase', {
                    addon_code: addon.code,
                    quantity: 1
                });

                if (response.checkout_url) {
                    window.location.href = response.checkout_url;
                }
            } catch (error) {
                billingLog.error('Error purchasing addon:', error);
                Utils.showToast(I18n.t('billing.messages.failed_to_purchase_addon'), 'error');
            } finally {
                this.purchasingAddon = null;
            }
        },

        async cancelAddon(addon) {
            if (!confirm(`Are you sure you want to cancel ${addon.addon_name}?`)) {
                return;
            }

            try {
                await apiClient.delete(`/vendor/billing/addons/${addon.id}`);
                Utils.showToast(I18n.t('billing.messages.addon_cancelled_successfully'), 'success');
                await this.loadData();
            } catch (error) {
                billingLog.error('Error cancelling addon:', error);
                Utils.showToast(I18n.t('billing.messages.failed_to_cancel_addon'), 'error');
            }
        },

        // Check if addon is already purchased
        isAddonPurchased(addonCode) {
            return this.myAddons.some(a => a.addon_code === addonCode && a.status === 'active');
        },

        // Formatters
        formatDate(dateString) {
            if (!dateString) return '-';
            const date = new Date(dateString);
            const locale = window.VENDOR_CONFIG?.locale || 'en-GB';
            return date.toLocaleDateString(locale, {
                year: 'numeric',
                month: 'short',
                day: 'numeric'
            });
        },

        formatCurrency(cents, currency = 'EUR') {
            if (cents === null || cents === undefined) return '-';
            const amount = cents / 100;
            const locale = window.VENDOR_CONFIG?.locale || 'en-GB';
            const currencyCode = window.VENDOR_CONFIG?.currency || currency;
            return new Intl.NumberFormat(locale, {
                style: 'currency',
                currency: currencyCode
            }).format(amount);
        }
    };
}