better states

public/js/modals/email-modal.js

@@ -25,6 +25,98 @@ function getEmailModalTitle(invoice, isOverdue) {
     if (invoice.email_status === 'sent') return `🔁 Resend Invoice #${invoice.invoice_number || invoice.id}`;
     return `📤 Send Invoice #${invoice.invoice_number || invoice.id}`;
 }
+function parseLocalDate(dateValue) {
+    if (!dateValue) return null;
+
+    if (dateValue instanceof Date) {
+        return new Date(dateValue.getFullYear(), dateValue.getMonth(), dateValue.getDate());
+    }
+
+    const dateStr = String(dateValue).split('T')[0];
+    const parts = dateStr.split('-').map(Number);
+
+    if (parts.length === 3 && parts.every(Number.isFinite)) {
+        return new Date(parts[0], parts[1] - 1, parts[2]);
+    }
+
+    const d = new Date(dateValue);
+    return Number.isNaN(d.getTime()) ? null : d;
+}
+
+function getLastSentDate(invoice) {
+    const sentDates = Array.isArray(invoice.sent_dates)
+        ? invoice.sent_dates.filter(Boolean)
+        : [];
+
+    if (sentDates.length > 0) {
+        return sentDates[sentDates.length - 1];
+    }
+
+    return null;
+}
+
+function getTermDays(invoice) {
+    const terms = String(invoice.terms || '').toLowerCase();
+
+    if (terms.includes('due on receipt') || terms.includes('upon receipt')) {
+        return 0;
+    }
+
+    const match = terms.match(/net\s*(\d+)/i);
+    if (match) {
+        return parseInt(match[1], 10);
+    }
+
+    return 30;
+}
+
+function addDays(dateValue, days) {
+    const d = parseLocalDate(dateValue);
+    if (!d) return null;
+
+    d.setDate(d.getDate() + days);
+    return d;
+}
+
+function getEffectiveDueDate(invoice) {
+    const lastSentDate = getLastSentDate(invoice);
+
+    // Nie versendet = kein Reminder/Overdue Text
+    if (!lastSentDate) {
+        return null;
+    }
+
+    if (invoice.due_date) {
+        return parseLocalDate(invoice.due_date);
+    }
+
+    return addDays(lastSentDate, getTermDays(invoice));
+}
+
+function getOverdueDays(invoice) {
+    const dueDate = getEffectiveDueDate(invoice);
+    if (!dueDate) return 0;
+
+    const today = new Date();
+    today.setHours(0, 0, 0, 0);
+
+    dueDate.setHours(0, 0, 0, 0);
+
+    return Math.max(0, Math.floor((today - dueDate) / 86400000));
+}
+
+function isInvoiceOverdue(invoice) {
+    const dueDate = getEffectiveDueDate(invoice);
+    if (!dueDate) return false;
+
+    const today = new Date();
+    today.setHours(0, 0, 0, 0);
+
+    dueDate.setHours(0, 0, 0, 0);
+
+    return !invoice.paid_date && dueDate < today;
+}
+
 function renderModalContent() {
     const modal = document.getElementById('email-modal');
     if (!modal) return;
@@ -34,13 +126,8 @@ function renderModalContent() {
     const stripeStatus = currentInvoice.stripe_payment_status || '';
     
     // Detect overdue: unpaid + older than 30 days
-    const invoiceDateParsed = currentInvoice.invoice_date 
-        ? new Date(currentInvoice.invoice_date.split('T')[0]) 
-        : null;
-    const daysSinceInvoice = invoiceDateParsed 
-        ? Math.floor((new Date() - invoiceDateParsed) / 86400000) 
-        : 0;
-    const isOverdue = !currentInvoice.paid_date && daysSinceInvoice > 30;
+    const isOverdue = isInvoiceOverdue(currentInvoice);
+    const daysOverdue = getOverdueDays(currentInvoice);
 
     const modalTitle = getEmailModalTitle(currentInvoice, isOverdue);
     
@@ -159,7 +246,7 @@ function renderModalContent() {
         defaultHtml = `
             <p>Dear ${customerName},</p>
             <p>We hope this message finds you well. Our records indicate that invoice <strong>#${invoiceNum}</strong> in the amount of <strong>$${totalDue}</strong>, dated ${formatDate(currentInvoice.invoice_date)}, remains unpaid.</p>
-            <p>This invoice is now <strong>${daysSinceInvoice} days past the invoice date</strong>. We kindly request prompt payment at your earliest convenience.</p>
+            <p>This invoice is now <strong>${daysOverdue} days overdue</strong>. We kindly request prompt payment at your earliest convenience.</p>
             <p>For your convenience, you can pay securely online using the payment link included below. We accept both Credit Card and ACH bank transfer.</p>
             <p>If payment has already been sent, please disregard this notice. Should you have any questions or need to discuss payment arrangements, please do not hesitate to reply to this email.</p>
             <p>Thank you for your attention to this matter. We value your business and look forward to continuing our partnership.</p>