Add Cache-Control: no-store for authenticated pages; fix payment onclick encoding

Prevents browsers from caching authenticated pages, which resolves stale/corrupt
cache bugs (e.g. Firefox refusing to navigate to a specific invoice). Also fixes
the Edit Payment button onclick to use Json.Serialize for Reference/Notes so
apostrophes and other special characters don't break the JavaScript string literal.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/PowderCoating.Application/Interfaces/IStripeConnectService.cs

@@ -20,7 +20,6 @@ public interface IStripeConnectService
         decimal invoiceTotal,
         decimal surchargeAmount,
         string currency,
-        string customerEmail,
         string invoiceNumber,
         int invoiceId);
 
@@ -33,7 +32,6 @@ public interface IStripeConnectService
         decimal depositAmount,
         decimal surchargeAmount,
         string currency,
-        string customerEmail,
         string quoteNumber,
         int quoteId);
 }

src/PowderCoating.Infrastructure/Services/StripeConnectService.cs

@@ -162,7 +162,6 @@ public class StripeConnectService : IStripeConnectService
         decimal invoiceTotal,
         decimal surchargeAmount,
         string currency,
-        string customerEmail,
         string invoiceNumber,
         int invoiceId)
     {
@@ -175,7 +174,6 @@ public class StripeConnectService : IStripeConnectService
             {
                 Amount = amountInCents,
                 Currency = currency.ToLower(),
-                ReceiptEmail = customerEmail,
                 Description = $"Invoice {invoiceNumber}",
                 Metadata = new Dictionary<string, string>
                 {
@@ -215,7 +213,6 @@ public class StripeConnectService : IStripeConnectService
         decimal depositAmount,
         decimal surchargeAmount,
         string currency,
-        string customerEmail,
         string quoteNumber,
         int quoteId)
     {
@@ -228,7 +225,6 @@ public class StripeConnectService : IStripeConnectService
             {
                 Amount = amountInCents,
                 Currency = currency.ToLower(),
-                ReceiptEmail = customerEmail,
                 Description = $"Deposit for quote {quoteNumber}",
                 Metadata = new Dictionary<string, string>
                 {

src/PowderCoating.Web/Controllers/InvoicesController.cs

@@ -1480,6 +1480,7 @@ public class InvoicesController : Controller
             }
 
             var currentUser = await _userManager.GetUserAsync(User);
+            var totalCreditCreated = 0m;  // populated inside transaction, used in success message
 
             await _unitOfWork.ExecuteInTransactionAsync(async () =>
             {
@@ -1499,6 +1500,75 @@ public class InvoicesController : Controller
                 await _unitOfWork.Payments.SoftDeleteAsync(payment.Id);
             }
 
+            // Re-release any deposits that were applied to this invoice so they can be
+            // auto-applied to the replacement invoice. Without this, AppliedToInvoiceId
+            // stays set and the deposit lookup (AppliedToInvoiceId == null) skips them.
+            var appliedDeposits = await _unitOfWork.Deposits.FindAsync(
+                d => d.AppliedToInvoiceId == invoice.Id && !d.IsDeleted);
+            var totalDepositReleased = 0m;
+            foreach (var deposit in appliedDeposits)
+            {
+                deposit.AppliedToInvoiceId = null;
+                deposit.AppliedDate = null;
+                deposit.UpdatedAt = DateTime.UtcNow;
+                await _unitOfWork.Deposits.UpdateAsync(deposit);
+                totalDepositReleased += deposit.Amount;
+            }
+            // Restore the CustomerDeposits 2300 liability that was cleared when the deposits
+            // were applied. Mirrors the DR at apply time; follows the same simplified reversal
+            // pattern as the rest of the void (regular payment GL entries are also left as-is).
+            if (totalDepositReleased > 0)
+            {
+                var custDepositsAcctId = await GetCustomerDepositsAccountIdAsync(invoice.CompanyId);
+                await _accountBalanceService.CreditAsync(custDepositsAcctId, totalDepositReleased);
+            }
+
+            // Convert non-deposit payments (cash, card, check, online) to customer credits so
+            // the money isn't lost when the invoice is voided. Each payment becomes a CRED-
+            // Deposit record linked to the same job; it will auto-apply when the replacement
+            // invoice is created, exactly like a normal deposit.
+            var nonDepositPayments = invoice.Payments
+                .Where(p => !p.IsDeleted && !(p.Reference ?? "").StartsWith("Deposit "))
+                .ToList();
+            if (nonDepositPayments.Any())
+            {
+                var credPrefix = $"CRED-{DateTime.UtcNow:yy}{DateTime.UtcNow.Month:D2}-";
+                var existingNums = (await _unitOfWork.Deposits.FindAsync(
+                        d => d.CompanyId == invoice.CompanyId && d.ReceiptNumber.StartsWith(credPrefix),
+                        ignoreQueryFilters: true))
+                    .Select(d => d.ReceiptNumber).ToList();
+                var maxNum = 0;
+                foreach (var rn in existingNums)
+                {
+                    var suffix = rn.Length >= credPrefix.Length + 4 ? rn[credPrefix.Length..] : "";
+                    if (int.TryParse(suffix, out int parsed) && parsed > maxNum) maxNum = parsed;
+                }
+
+                var creditCustDepositsAcctId = await GetCustomerDepositsAccountIdAsync(invoice.CompanyId);
+                foreach (var payment in nonDepositPayments)
+                {
+                    maxNum++;
+                    await _unitOfWork.Deposits.AddAsync(new Core.Entities.Deposit
+                    {
+                        CompanyId     = invoice.CompanyId,
+                        CustomerId    = invoice.CustomerId,
+                        JobId         = invoice.JobId,
+                        Amount        = payment.Amount,
+                        PaymentMethod = payment.PaymentMethod,
+                        ReceivedDate  = payment.PaymentDate,
+                        Reference     = payment.Reference,
+                        Notes         = $"Credit from voided invoice {invoice.InvoiceNumber}" +
+                                        (string.IsNullOrWhiteSpace(payment.Notes) ? "." : $". Original: {payment.Notes}"),
+                        ReceiptNumber = $"{credPrefix}{maxNum:D4}",
+                        CreatedAt     = DateTime.UtcNow
+                    });
+                    totalCreditCreated += payment.Amount;
+                }
+
+                // CR CustomerDeposits to create the liability matching the cash already in Checking
+                await _accountBalanceService.CreditAsync(creditCustDepositsAcctId, totalCreditCreated);
+            }
+
             // Void any gift certificates that were generated from this invoice.
             // Capture each GC's remaining balance BEFORE voiding so the GL entries below can use it.
             var gcLiabilityAcctId = await GetGcLiabilityAccountIdAsync(invoice.CompanyId);
@@ -1550,7 +1620,10 @@ public class InvoicesController : Controller
 
             }); // end ExecuteInTransactionAsync
 
-            TempData["Success"] = $"Invoice {invoice.InvoiceNumber} has been voided.";
+            var creditMsg = totalCreditCreated > 0
+                ? $" {totalCreditCreated:C} converted to customer credit and will auto-apply to the next invoice."
+                : "";
+            TempData["Success"] = $"Invoice {invoice.InvoiceNumber} has been voided.{creditMsg}";
             return RedirectToAction(nameof(Details), new { id });
         }
         catch (Exception ex)
@@ -3035,6 +3108,50 @@ public class InvoicesController : Controller
         return false;
     }
 
+    /// <summary>
+    /// Inline-edits description, quantity, and unit price on a single invoice line item.
+    /// Blocked on paid/voided invoices (same gate as the full Edit action).
+    /// Returns updated totals so the page can reflect the change without a reload.
+    /// </summary>
+    [HttpPost]
+    [ValidateAntiForgeryToken]
+    public async Task<IActionResult> PatchItem([FromBody] PatchInvoiceItemRequest request)
+    {
+        var currentUser = await _userManager.GetUserAsync(User);
+        if (currentUser == null) return Unauthorized();
+
+        var item = await _unitOfWork.InvoiceItems.GetByIdAsync(request.ItemId);
+        if (item == null) return NotFound();
+
+        var invoice = await _unitOfWork.Invoices.GetByIdAsync(item.InvoiceId);
+        if (invoice == null || invoice.CompanyId != currentUser.CompanyId) return NotFound();
+
+        if (invoice.Status is not (InvoiceStatus.Draft or InvoiceStatus.Sent or InvoiceStatus.Overdue))
+            return BadRequest(new { error = "Cannot edit items on a paid or voided invoice." });
+
+        item.Description = request.Description.Trim();
+        item.Quantity    = request.Quantity;
+        item.UnitPrice   = request.UnitPrice;
+        item.TotalPrice  = Math.Round(request.Quantity * request.UnitPrice, 2);
+        await _unitOfWork.InvoiceItems.UpdateAsync(item);
+
+        var allItems    = await _unitOfWork.InvoiceItems.FindAsync(ii => ii.InvoiceId == invoice.Id);
+        var newSubTotal = allItems.Sum(i => i.TotalPrice);
+        invoice.SubTotal   = newSubTotal;
+        invoice.TaxAmount  = Math.Round(newSubTotal * invoice.TaxPercent / 100m, 2);
+        invoice.Total      = Math.Round(newSubTotal - invoice.DiscountAmount + invoice.TaxAmount, 2);
+        await _unitOfWork.Invoices.UpdateAsync(invoice);
+        await _unitOfWork.CompleteAsync();
+
+        return Json(new {
+            lineTotal  = item.TotalPrice,
+            subtotal   = invoice.SubTotal,
+            taxAmount  = invoice.TaxAmount,
+            total      = invoice.Total,
+            balanceDue = invoice.BalanceDue
+        });
+    }
+
     /// <summary>
     /// Returns logo bytes and content type for PDF generation.
     /// Prefers blob-stored logos (LogoFilePath) over the legacy DB column (LogoData).
@@ -3050,3 +3167,11 @@ public class InvoicesController : Controller
         return (company.LogoData, company.LogoContentType);
     }
 }
+
+public class PatchInvoiceItemRequest
+{
+    public int     ItemId      { get; set; }
+    public string  Description { get; set; } = string.Empty;
+    public decimal Quantity    { get; set; }
+    public decimal UnitPrice   { get; set; }
+}

src/PowderCoating.Web/Controllers/JobsController.cs

@@ -4216,9 +4216,69 @@ public class JobsController : Controller
             return Json(new { success = false, message = "An error occurred. Please try again." });
         }
     }
+
+    /// <summary>
+    /// Inline-edits description, quantity, and unit price on a single job line item.
+    /// Adjusts FinalPrice and the stored PricingBreakdownJson snapshot by the price delta.
+    /// Returns updated totals so the page can reflect the change without a reload.
+    /// </summary>
+    [HttpPost]
+    [ValidateAntiForgeryToken]
+    public async Task<IActionResult> PatchItem([FromBody] PatchJobItemRequest request)
+    {
+        var currentUser = await _userManager.GetUserAsync(User);
+        if (currentUser == null) return Unauthorized();
+
+        var item = await _unitOfWork.JobItems.GetByIdAsync(request.ItemId);
+        if (item == null) return NotFound();
+
+        var job = await _unitOfWork.Jobs.GetByIdAsync(item.JobId);
+        if (job == null || job.CompanyId != currentUser.CompanyId) return NotFound();
+
+        var oldTotal     = item.TotalPrice;
+        item.Description = request.Description.Trim();
+        item.Quantity    = request.Quantity;
+        item.UnitPrice   = request.UnitPrice;
+        item.TotalPrice  = Math.Round(request.Quantity * request.UnitPrice, 2);
+        await _unitOfWork.JobItems.UpdateAsync(item);
+
+        var delta     = item.TotalPrice - oldTotal;
+        job.FinalPrice = Math.Round(job.FinalPrice + delta, 2);
+
+        // Keep the stored pricing snapshot in sync so the breakdown panel stays consistent
+        if (!string.IsNullOrEmpty(job.PricingBreakdownJson))
+        {
+            var pb = JsonSerializer.Deserialize<QuotePricingBreakdownDto>(job.PricingBreakdownJson);
+            if (pb != null)
+            {
+                pb.ItemsSubtotal          += delta;
+                pb.SubtotalBeforeDiscount += delta;
+                pb.SubtotalAfterDiscount   = pb.SubtotalBeforeDiscount - pb.DiscountAmount;
+                pb.TaxAmount               = Math.Round(pb.SubtotalAfterDiscount * pb.TaxPercent / 100m, 2);
+                pb.Total                   = Math.Round(pb.SubtotalAfterDiscount + pb.RushFee + pb.TaxAmount, 2);
+                job.FinalPrice             = pb.Total;
+                job.PricingBreakdownJson   = JsonSerializer.Serialize(pb);
+            }
+        }
+
+        await _unitOfWork.Jobs.UpdateAsync(job);
+        await _unitOfWork.CompleteAsync();
+
+        return Json(new {
+            lineTotal  = item.TotalPrice,
+            finalPrice = job.FinalPrice
+        });
+    }
 }
 
 public class DeleteTimeEntryRequest { public int Id { get; set; } }
+public class PatchJobItemRequest
+{
+    public int     ItemId      { get; set; }
+    public string  Description { get; set; } = string.Empty;
+    public decimal Quantity    { get; set; }
+    public decimal UnitPrice   { get; set; }
+}
 public class LogMaterialRequest
 {
     public int     JobId           { get; set; }

src/PowderCoating.Web/Controllers/PaymentController.cs

@@ -75,7 +75,6 @@ public class PaymentController : Controller
             CustomerName     = customer != null
                 ? $"{customer.ContactFirstName} {customer.ContactLastName}".Trim()
                 : "Valued Customer",
-            CustomerEmail    = customer?.Email ?? string.Empty,
             CompanyName      = company!.CompanyName,
             BalanceDue       = invoice.BalanceDue,
             InvoiceTotal     = invoice.Total,
@@ -127,8 +126,6 @@ public class PaymentController : Controller
             return BadRequest(new { error = "Invalid payment amount." });
 
         var surcharge = CalculateSurcharge(request.Amount, company!);
-        var customer = await _context.Customers.AsNoTracking()
-            .FirstOrDefaultAsync(c => c.Id == invoice.CustomerId);
 
         var (success, clientSecret, paymentIntentId, stripeError) =
             await _stripeConnect.CreatePaymentIntentAsync(
@@ -136,7 +133,6 @@ public class PaymentController : Controller
                 invoiceTotal: request.Amount,
                 surchargeAmount: surcharge,
                 currency: "usd",
-                customerEmail: customer?.Email ?? string.Empty,
                 invoiceNumber: invoice.InvoiceNumber,
                 invoiceId: invoice.Id);
 
@@ -261,7 +257,6 @@ public class PaymentController : Controller
             CustomerName         = customer != null
                 ? $"{customer.ContactFirstName} {customer.ContactLastName}".Trim()
                 : quote.ProspectContactName ?? "Valued Customer",
-            CustomerEmail        = customer?.Email ?? quote.ProspectEmail ?? string.Empty,
             CompanyName          = company!.CompanyName,
             DepositAmount        = depositAmount,
             QuoteTotal           = quote.Total,
@@ -296,7 +291,6 @@ public class PaymentController : Controller
 
         var depositAmount = Math.Round(quote!.Total * (quote.DepositPercent / 100m), 2);
         var surcharge = CalculateSurcharge(depositAmount, company!);
-        var customerEmail = quote.Customer?.Email ?? quote.ProspectEmail ?? string.Empty;
 
         var (success, clientSecret, paymentIntentId, stripeError) =
             await _stripeConnect.CreateDepositPaymentIntentAsync(
@@ -304,7 +298,6 @@ public class PaymentController : Controller
                 depositAmount: depositAmount,
                 surchargeAmount: surcharge,
                 currency: "usd",
-                customerEmail: customerEmail,
                 quoteNumber: quote.QuoteNumber,
                 quoteId: quote.Id);
 
@@ -942,7 +935,6 @@ public class PaymentPageViewModel
     public int InvoiceId { get; set; }
     public string Token { get; set; } = string.Empty;
     public string CustomerName { get; set; } = string.Empty;
-    public string CustomerEmail { get; set; } = string.Empty;
     public string CompanyName { get; set; } = string.Empty;
     public decimal BalanceDue { get; set; }
     public decimal InvoiceTotal { get; set; }
@@ -963,7 +955,6 @@ public class DepositPaymentPageViewModel
     public int    QuoteId              { get; set; }
     public string Token                { get; set; } = string.Empty;
     public string CustomerName         { get; set; } = string.Empty;
-    public string CustomerEmail        { get; set; } = string.Empty;
     public string CompanyName          { get; set; } = string.Empty;
     public decimal DepositAmount       { get; set; }
     public decimal QuoteTotal          { get; set; }

src/PowderCoating.Web/Controllers/QuotesController.cs

@@ -3824,6 +3824,49 @@ public class QuotesController : Controller
         }
         return (company.LogoData, company.LogoContentType);
     }
+
+    /// <summary>
+    /// Inline-edits description, quantity, and unit price on a single quote line item.
+    /// Adjusts stored quote totals by the price delta so the sidebar stays accurate.
+    /// Returns updated totals so the page can reflect the change without a reload.
+    /// </summary>
+    [HttpPost]
+    [ValidateAntiForgeryToken]
+    public async Task<IActionResult> PatchItem([FromBody] PatchQuoteItemRequest request)
+    {
+        var currentUser = await _userManager.GetUserAsync(User);
+        if (currentUser == null) return Unauthorized();
+
+        var item = await _unitOfWork.QuoteItems.GetByIdAsync(request.ItemId);
+        if (item == null) return NotFound();
+
+        var quote = await _unitOfWork.Quotes.GetByIdAsync(item.QuoteId);
+        if (quote == null || quote.CompanyId != currentUser.CompanyId) return NotFound();
+
+        var oldTotal        = item.TotalPrice;
+        item.Description    = request.Description.Trim();
+        item.Quantity       = request.Quantity;
+        item.UnitPrice      = request.UnitPrice;
+        item.TotalPrice     = Math.Round(request.Quantity * request.UnitPrice, 2);
+        await _unitOfWork.QuoteItems.UpdateAsync(item);
+
+        // Cascade delta through stored totals without re-running the pricing engine
+        var delta                    = item.TotalPrice - oldTotal;
+        quote.ItemsSubtotal         += delta;
+        quote.SubTotal              += delta;
+        quote.SubtotalAfterDiscount  = quote.SubTotal - quote.DiscountAmount;
+        quote.TaxAmount              = Math.Round(quote.SubtotalAfterDiscount * quote.TaxPercent / 100m, 2);
+        quote.Total                  = Math.Round(quote.SubtotalAfterDiscount + quote.RushFee + quote.TaxAmount, 2);
+        await _unitOfWork.Quotes.UpdateAsync(quote);
+        await _unitOfWork.CompleteAsync();
+
+        return Json(new {
+            lineTotal = item.TotalPrice,
+            subtotal  = quote.SubTotal,
+            taxAmount = quote.TaxAmount,
+            total     = quote.Total
+        });
+    }
 }
 
 // Request model for AJAX pricing calculation
@@ -3834,3 +3877,11 @@ public class UpdateQuoteStatusRequest
     public int QuoteId { get; set; }
     public int StatusId { get; set; }
 }
+
+public class PatchQuoteItemRequest
+{
+    public int     ItemId      { get; set; }
+    public string  Description { get; set; } = string.Empty;
+    public decimal Quantity    { get; set; }
+    public decimal UnitPrice   { get; set; }
+}

src/PowderCoating.Web/Program.cs

@@ -653,6 +653,11 @@ app.Use(async (context, next) =>
     context.Response.Headers.Append("Permissions-Policy",
         "geolocation=(), microphone=(), camera=()");
 
+    // Prevent browsers from caching authenticated pages — avoids stale data and
+    // browser-specific cache corruption bugs (e.g. Firefox caching a partial load).
+    if (context.User.Identity?.IsAuthenticated == true)
+        context.Response.Headers.Append("Cache-Control", "no-store");
+
     await next();
 });
 

src/PowderCoating.Web/Views/Invoices/Details.cshtml

@@ -28,6 +28,9 @@
     var onlinePaymentsEnabled = ViewBag.OnlinePaymentsEnabled == true;
     var showOnlinePaymentCard = !isDraft && !isVoided && Model.BalanceDue > 0 && onlinePaymentsEnabled;
     var guidedActivationCallout = ViewBag.GuidedActivationCallout as PowderCoating.Web.ViewModels.GuidedActivation.GuidedActivationCalloutViewModel;
+    var nonDepositPaymentTotal = Model.Payments
+        .Where(p => !(p.Reference ?? "").StartsWith("Deposit "))
+        .Sum(p => p.Amount);
 }
 
 <div class="row justify-content-center">
@@ -230,21 +233,21 @@
                                 <tbody>
                                     @foreach (var item in Model.InvoiceItems)
                                     {
-                                        <tr>
+                                        <tr data-item-id="@item.Id">
                                             <td>
-                                                <div class="fw-semibold">@item.Description</div>
+                                                <span class="fw-semibold" data-inline-field="description" data-raw-value="@item.Description">@item.Description</span>
                                                 @if (!string.IsNullOrWhiteSpace(item.ColorName))
                                                 {
-                                                    <small class="text-muted">@item.ColorName</small>
+                                                    <small class="text-muted d-block">@item.ColorName</small>
                                                 }
                                                 @if (!string.IsNullOrWhiteSpace(item.Notes))
                                                 {
                                                     <small class="text-muted d-block">@item.Notes</small>
                                                 }
                                             </td>
-                                            <td class="text-center">@item.Quantity.ToString("G")</td>
-                                            <td class="text-end">@item.UnitPrice.ToString("C")</td>
-                                            <td class="text-end fw-semibold">@item.TotalPrice.ToString("C")</td>
+                                            <td class="text-center"><span data-inline-field="quantity" data-raw-value="@item.Quantity">@item.Quantity.ToString("G")</span></td>
+                                            <td class="text-end"><span data-inline-field="unitPrice" data-raw-value="@item.UnitPrice">@item.UnitPrice.ToString("C")</span></td>
+                                            <td class="text-end fw-semibold" data-line-total>@item.TotalPrice.ToString("C")</td>
                                         </tr>
                                     }
                                 </tbody>
@@ -257,7 +260,7 @@
                                 <div class="col-md-4">
                                     <div class="d-flex justify-content-between mb-1">
                                         <span class="text-muted">Subtotal</span>
-                                        <span>@Model.SubTotal.ToString("C")</span>
+                                        <span id="inv-subtotal">@Model.SubTotal.ToString("C")</span>
                                     </div>
                                     @if (Model.DiscountAmount > 0)
                                     {
@@ -276,12 +279,12 @@
                                                     <span class="badge bg-warning-subtle text-warning-emphasis ms-1 small fw-normal">@Model.SalesTaxAccountName</span>
                                                 }
                                             </span>
-                                            <span>@Model.TaxAmount.ToString("C")</span>
+                                            <span id="inv-tax">@Model.TaxAmount.ToString("C")</span>
                                         </div>
                                     }
                                     <div class="d-flex justify-content-between fw-bold border-top pt-2 mt-1 fs-5">
                                         <span>Total</span>
-                                        <span>@Model.Total.ToString("C")</span>
+                                        <span id="inv-total">@Model.Total.ToString("C")</span>
                                     </div>
                                     @if (Model.AmountPaid > 0)
                                     {
@@ -291,7 +294,7 @@
                                         </div>
                                         <div class="d-flex justify-content-between fw-bold border-top pt-2 mt-1">
                                             <span>Balance Due</span>
-                                            <span class="@(Model.BalanceDue > 0 ? "text-danger" : "text-success")">@Model.BalanceDue.ToString("C")</span>
+                                            <span id="inv-balance" class="@(Model.BalanceDue > 0 ? "text-danger" : "text-success")">@Model.BalanceDue.ToString("C")</span>
                                         </div>
                                     }
                                 </div>
@@ -406,7 +409,7 @@
                                                     @if (!isVoided)
                                                     {
                                                         <button type="button" class="btn btn-sm btn-outline-secondary me-1" title="Edit payment"
-                                                                onclick="openEditPaymentModal(@p.Id, @Model.Id, '@p.PaymentDate.ToString("yyyy-MM-dd")', @((int)p.PaymentMethod), '@(p.Reference ?? "")', '@(p.Notes ?? "")', @(p.DepositAccountId?.ToString() ?? "null"))">
+                                                                onclick="openEditPaymentModal(@p.Id, @Model.Id, '@p.PaymentDate.ToString("yyyy-MM-dd")', @((int)p.PaymentMethod), @Json.Serialize(p.Reference ?? ""), @Json.Serialize(p.Notes ?? ""), @(p.DepositAccountId?.ToString() ?? "null"))">
                                                             <i class="bi bi-pencil"></i>
                                                         </button>
                                                         <form asp-action="DeletePayment" asp-route-invoiceId="@Model.Id" asp-route-paymentId="@p.Id"
@@ -694,7 +697,9 @@
                             @if (!isVoided && Model.Status != InvoiceStatus.Paid)
                             {
                                 <form asp-action="Void" asp-route-id="@Model.Id" method="post"
-                                      onsubmit="return confirm('Void this invoice? This will reverse the remaining balance on the customer account.')">
+                                      onsubmit="return confirm('@(nonDepositPaymentTotal > 0
+                                          ? $"Void this invoice? {nonDepositPaymentTotal.ToString("C")} in payments will be converted to a customer credit and auto-applied to the next invoice."
+                                          : "Void this invoice? This will reverse the remaining balance on the customer account.")')">
                                     @Html.AntiForgeryToken()
                                     <button type="submit" class="btn btn-outline-warning w-100">
                                         <i class="bi bi-x-circle me-2"></i>Void Invoice
@@ -1442,6 +1447,19 @@
 }
 
 @section Scripts {
+<script src="~/js/inline-item-edit.js"></script>
+<script>
+    window.inlineItemEdit = {
+        patchUrl: '@Url.Action("PatchItem", "Invoices")',
+        canEdit:  @Json.Serialize(canEdit),
+        totals: {
+            subtotal:   '#inv-subtotal',
+            tax:        '#inv-tax',
+            total:      '#inv-total',
+            balance:    '#inv-balance'
+        }
+    };
+</script>
 <script>
     function submitSendInvoice(sendEmail, sendSms) {
         document.getElementById('sendInvoiceSendEmail').value = sendEmail ? 'true' : 'false';

src/PowderCoating.Web/Views/Jobs/Details.cshtml

@@ -341,9 +341,9 @@
                                         @foreach (var item in catalogItems)
                                         {
                                             var catIdx = allItems.IndexOf(item);
-                                            <tr>
+                                            <tr data-item-id="@item.Id">
                                                 <td>
-                                                    <strong>@item.Description</strong>
+                                                    <span data-inline-field="description" data-raw-value="@item.Description"><strong>@item.Description</strong></span>
                                                     @if (item.Coats != null && item.Coats.Any())
                                                     {
                                                         <br />
@@ -399,9 +399,9 @@
                                                         <br /><small class="text-muted"><i class="bi bi-sticky me-1"></i>@item.Notes</small>
                                                     }
                                                 </td>
-                                                <td class="text-center">@item.Quantity</td>
-                                                <td class="text-end">@item.UnitPrice.ToString("C")</td>
-                                                <td class="text-end fw-semibold">@item.TotalPrice.ToString("C")</td>
+                                                <td class="text-center"><span data-inline-field="quantity" data-raw-value="@item.Quantity">@item.Quantity</span></td>
+                                                <td class="text-end"><span data-inline-field="unitPrice" data-raw-value="@item.UnitPrice">@item.UnitPrice.ToString("C")</span></td>
+                                                <td class="text-end fw-semibold" data-line-total>@item.TotalPrice.ToString("C")</td>
                                                 <td class="text-center">
                                                     <div class="btn-group btn-group-sm">
                                                         <button type="button" class="btn btn-outline-secondary" onclick="openWizard(@catIdx)" title="Edit"><i class="bi bi-pencil"></i></button>
@@ -440,6 +440,7 @@
                                         {
                                             var custIdx = allItems.IndexOf(item);
                                             // Use stored PowderToOrder per coat; fall back to calculating from efficiency data
+                                            // Note: row has data-item-id for inline editing
                                             decimal totalPowderNeeded = 0;
                                             if (item.Coats != null && item.Coats.Any(c => c.PowderToOrder > 0))
                                             {
@@ -458,9 +459,9 @@
                                             {
                                                 totalPowderNeeded = (item.SurfaceAreaSqFt * item.Quantity) / (30m * 0.65m);
                                             }
-                                            <tr>
+                                            <tr data-item-id="@item.Id">
                                                 <td>
-                                                    <strong>@item.Description</strong>
+                                                    <span data-inline-field="description" data-raw-value="@item.Description"><strong>@item.Description</strong></span>
                                                     @if (item.RequiresSandblasting || item.RequiresMasking)
                                                     {
                                                         <br />
@@ -528,7 +529,7 @@
                                                         <br /><small class="text-muted"><i class="bi bi-sticky me-1"></i>@item.Notes</small>
                                                     }
                                                 </td>
-                                                <td class="text-center">@item.Quantity</td>
+                                                <td class="text-center"><span data-inline-field="quantity" data-raw-value="@item.Quantity">@item.Quantity</span></td>
                                                 <td class="text-center">
                                                     @if (item.SurfaceAreaSqFt > 0)
                                                     {
@@ -553,8 +554,8 @@
                                                     }
                                                     else { <span class="text-muted">&mdash;</span> }
                                                 </td>
-                                                <td class="text-end">@item.UnitPrice.ToString("C")</td>
-                                                <td class="text-end fw-semibold">@item.TotalPrice.ToString("C")</td>
+                                                <td class="text-end"><span data-inline-field="unitPrice" data-raw-value="@item.UnitPrice">@item.UnitPrice.ToString("C")</span></td>
+                                                <td class="text-end fw-semibold" data-line-total>@item.TotalPrice.ToString("C")</td>
                                                 <td class="text-center">
                                                     <div class="btn-group btn-group-sm">
                                                         <button type="button" class="btn btn-outline-secondary" onclick="openWizard(@custIdx)" title="Edit"><i class="bi bi-pencil"></i></button>
@@ -590,15 +591,15 @@
                                         @foreach (var item in laborItems)
                                         {
                                             var labIdx = allItems.IndexOf(item);
-                                            <tr>
+                                            <tr data-item-id="@item.Id">
                                                 <td>
-                                                    <strong>@item.Description</strong>
+                                                    <span data-inline-field="description" data-raw-value="@item.Description"><strong>@item.Description</strong></span>
                                                     @if (!string.IsNullOrEmpty(item.Notes))
                                                     {
                                                         <br /><small class="text-muted"><i class="bi bi-sticky me-1"></i>@item.Notes</small>
                                                     }
                                                 </td>
-                                                <td class="text-center">@item.Quantity</td>
+                                                <td class="text-center"><span data-inline-field="quantity" data-raw-value="@item.Quantity">@item.Quantity</span></td>
                                                 <td class="text-center">
                                                     @if (item.EstimatedMinutes > 0)
                                                     {
@@ -606,8 +607,8 @@
                                                     }
                                                     else { <span class="text-muted">&mdash;</span> }
                                                 </td>
-                                                <td class="text-end">@item.UnitPrice.ToString("C")</td>
-                                                <td class="text-end fw-semibold">@item.TotalPrice.ToString("C")</td>
+                                                <td class="text-end"><span data-inline-field="unitPrice" data-raw-value="@item.UnitPrice">@item.UnitPrice.ToString("C")</span></td>
+                                                <td class="text-end fw-semibold" data-line-total>@item.TotalPrice.ToString("C")</td>
                                                 <td class="text-center">
                                                     <div class="btn-group btn-group-sm">
                                                         <button type="button" class="btn btn-outline-secondary" onclick="openWizard(@labIdx)" title="Edit"><i class="bi bi-pencil"></i></button>
@@ -1688,7 +1689,7 @@
                                     }
                                     <div class="d-flex justify-content-between fw-bold border-top pt-2 mt-1">
                                         <span>Total</span>
-                                        <span>@jobPb.Total.ToString("C")</span>
+                                        <span class="job-final-price-display">@jobPb.Total.ToString("C")</span>
                                     </div>
                                     @{
                                         var jobTotalDirectCost = jobPb.MaterialCosts + jobPb.LaborCosts + jobPb.EquipmentCosts + jobPb.OvenBatchCost + jobPb.FacilityOverheadCost + jobPb.ShopSuppliesAmount;
@@ -1717,7 +1718,7 @@
                             }
                             <div>
                                 <label class="text-muted small mb-1">Final Price</label>
-                                <h3 class="mb-0 text-primary">@Model.FinalPrice.ToString("C")</h3>
+                                <h3 class="mb-0 text-primary job-final-price-display">@Model.FinalPrice.ToString("C")</h3>
                             </div>
                         }
                     </div>
@@ -2415,6 +2416,16 @@
     <link rel="stylesheet" href="~/css/job-photos.css" />
     <script src="~/js/job-photos.js" asp-append-version="true"></script>
     <script src="~/js/customer-change.js" asp-append-version="true"></script>
+    <script src="~/js/inline-item-edit.js" asp-append-version="true"></script>
+    <script>
+        window.inlineItemEdit = {
+            patchUrl: '@Url.Action("PatchItem", "Jobs")',
+            canEdit:  true,
+            totals: {
+                finalPrice: '.job-final-price-display'
+            }
+        };
+    </script>
     <script>
         // -- Inline date editing ----------------------------------------------
         const jobId = @Model.Id;

src/PowderCoating.Web/Views/Payment/Index.cshtml

@@ -75,11 +75,11 @@
                 <div class="input-group mb-1">
                     <span class="input-group-text">$</span>
                     <input type="number" id="paymentAmount" class="form-control"
-                           value="@Model.BalanceDue.ToString("F2")"
-                           min="0.01" max="@Model.BalanceDue.ToString("F2")" step="0.01"
+                           value="@Model.TotalWithSurcharge.ToString("F2")"
+                           min="0.01" max="@Model.TotalWithSurcharge.ToString("F2")" step="0.01"
                            oninput="updateSurcharge()" />
                 </div>
-                <div class="form-text">Max: @Model.BalanceDue.ToString("C")</div>
+                <div class="form-text">Max: @Model.TotalWithSurcharge.ToString("C")</div>
             </div>
         </div>
 
@@ -116,18 +116,17 @@
     const STRIPE_PK  = '@Model.StripePublishableKey';
     const ACCOUNT_ID = '@Model.StripeAccountId';
     const TOKEN      = '@Model.Token';
-    const MAX_AMOUNT = @Model.BalanceDue.ToString("F2");
+    const MAX_TOTAL  = @Model.TotalWithSurcharge.ToString("F2", System.Globalization.CultureInfo.InvariantCulture);
     const SURCHARGE_TYPE  = '@Model.SurchargeType';
-    const SURCHARGE_VALUE = @Model.SurchargeValue.ToString("F4");
+    const SURCHARGE_VALUE = @Model.SurchargeValue.ToString("F4", System.Globalization.CultureInfo.InvariantCulture);
     const SUCCESS_URL = `/pay/${TOKEN}/success`;
 
     const stripe = Stripe(STRIPE_PK, { stripeAccount: ACCOUNT_ID });
     let elements, paymentElement;
 
     async function initStripe() {
-        const amount = parseFloat(document.getElementById('paymentAmount').value) || MAX_AMOUNT;
-        const surcharge = calcSurcharge(amount);
-        const total = Math.round((amount + surcharge) * 100) / 100;
+        // Input value is the total the customer pays (including fee)
+        const total = parseFloat(document.getElementById('paymentAmount').value) || MAX_TOTAL;
 
         elements = stripe.elements({
             mode: 'payment',
@@ -141,12 +140,15 @@
         paymentElement.mount('#payment-element');
     }
 
-    function calcSurcharge(amount) {
+    // Back-calculates the base invoice amount from a total that includes the fee.
+    // Server receives the base and adds surcharge on top — both paths arrive at the same
+    // PaymentIntent amount so Stripe.js never sees an amount mismatch.
+    function calcBaseFromTotal(total) {
         if (SURCHARGE_TYPE === 'Percent')
-            return Math.round(amount * (SURCHARGE_VALUE / 100) * 100) / 100;
+            return Math.round(total / (1 + SURCHARGE_VALUE / 100) * 100) / 100;
         if (SURCHARGE_TYPE === 'Flat')
-            return SURCHARGE_VALUE;
-        return 0;
+            return Math.max(0, Math.round((total - SURCHARGE_VALUE) * 100) / 100);
+        return total;
     }
 
     function formatCurrency(val) {
@@ -154,9 +156,9 @@
     }
 
     function updateSurcharge() {
-        const amount = Math.min(parseFloat(document.getElementById('paymentAmount').value) || 0, MAX_AMOUNT);
-        const surcharge = calcSurcharge(amount);
-        const total = amount + surcharge;
+        const total = Math.min(parseFloat(document.getElementById('paymentAmount').value) || 0, MAX_TOTAL);
+        const base = calcBaseFromTotal(total);
+        const surcharge = Math.round((total - base) * 100) / 100;
 
         const surchargeEl = document.getElementById('surchargeDisplay');
         const totalEl = document.getElementById('totalWithSurchargeDisplay');
@@ -164,7 +166,10 @@
 
         if (surchargeEl) surchargeEl.textContent = formatCurrency(surcharge);
         if (totalEl) totalEl.textContent = formatCurrency(total);
-        if (btnAmtEl) btnAmtEl.textContent = surcharge > 0 ? formatCurrency(total) : formatCurrency(amount);
+        if (btnAmtEl) btnAmtEl.textContent = formatCurrency(total);
+
+        // Keep Elements in sync so confirmPayment amount matches the PaymentIntent
+        if (elements) elements.update({ amount: Math.round(total * 100) });
     }
 
     async function submitPayment() {
@@ -172,13 +177,21 @@
         const msgEl = document.getElementById('payment-message');
         const amountInput = document.getElementById('paymentAmount');
 
-        const amount = parseFloat(amountInput.value);
-        if (!amount || amount <= 0 || amount > MAX_AMOUNT) {
+        const total = parseFloat(amountInput.value);
+        if (!total || total <= 0 || total > MAX_TOTAL) {
             msgEl.textContent = 'Please enter a valid payment amount.';
             msgEl.style.display = '';
             return;
         }
 
+        // Back-calculate base; server adds surcharge on top as usual
+        const base = calcBaseFromTotal(total);
+        if (base <= 0) {
+            msgEl.textContent = 'Payment amount must exceed the convenience fee.';
+            msgEl.style.display = '';
+            return;
+        }
+
         btn.disabled = true;
         document.getElementById('submitText').style.display = 'none';
         document.getElementById('submitSpinner').style.display = '';
@@ -195,13 +208,13 @@
             return;
         }
 
-        // Create PaymentIntent on server
+        // Create PaymentIntent on server — send base amount (server adds surcharge)
         let clientSecret;
         try {
             const resp = await fetch(`/pay/${TOKEN}/intent`, {
                 method: 'POST',
                 headers: { 'Content-Type': 'application/json' },
-                body: JSON.stringify({ amount })
+                body: JSON.stringify({ amount: base })
             });
             const data = await resp.json();
             if (!resp.ok) {

src/PowderCoating.Web/Views/Quotes/Details.cshtml

@@ -276,14 +276,14 @@
                                         <tbody>
                                             @foreach (var item in catalogItems)
                                             {
-                                                <tr>
+                                                <tr data-item-id="@item.Id">
                                                     <td>
                                                         @{
                                                             var displayDescription = item.Description == "Product Item" || string.IsNullOrWhiteSpace(item.Description)
                                                                 ? (item.CatalogItemName ?? "Catalog Item")
                                                                 : item.Description;
                                                         }
-                                                        <strong>@displayDescription</strong>
+                                                        <span data-inline-field="description" data-raw-value="@displayDescription"><strong>@displayDescription</strong></span>
                                                         @if (item.CatalogItemId.HasValue &&
                                                              item.Description != "Product Item" &&
                                                              !string.IsNullOrWhiteSpace(item.Description))
@@ -354,9 +354,9 @@
                                                             <small class="text-muted"><i class="bi bi-sticky"></i> <strong>Notes:</strong> @item.Notes</small>
                                                         }
                                                     </td>
-                                                    <td>@item.Quantity</td>
-                                                    <td>@item.UnitPrice.ToString("C")</td>
-                                                    <td><strong>@item.TotalPrice.ToString("C")</strong></td>
+                                                    <td><span data-inline-field="quantity" data-raw-value="@item.Quantity">@item.Quantity</span></td>
+                                                    <td><span data-inline-field="unitPrice" data-raw-value="@item.UnitPrice">@item.UnitPrice.ToString("C")</span></td>
+                                                    <td data-line-total><strong>@item.TotalPrice.ToString("C")</strong></td>
                                                 </tr>
                                             }
                                         </tbody>
@@ -394,9 +394,9 @@
                                                 var totalSqFt = item.SurfaceAreaSqFt * item.Quantity;
                                                 var powderOnPart = totalSqFt / coverageRate;
                                                 var totalPowderNeeded = powderOnPart / transferEff;
-                                                <tr>
+                                                <tr data-item-id="@item.Id">
                                                     <td>
-                                                        <strong>@item.Description</strong>
+                                                        <span data-inline-field="description" data-raw-value="@item.Description"><strong>@item.Description</strong></span>
 
                                                         @* Display coating layers *@
                                                         @if (item.Coats != null && item.Coats.Any())
@@ -474,7 +474,7 @@
                                                             <small class="text-muted"><i class="bi bi-sticky"></i> <strong>Notes:</strong> @item.Notes</small>
                                                         }
                                                     </td>
-                                                    <td>@item.Quantity</td>
+                                                    <td><span data-inline-field="quantity" data-raw-value="@item.Quantity">@item.Quantity</span></td>
                                                     <td>
                                                         @item.SurfaceAreaSqFt.ToString("F2") @ViewBag.AreaUnit
                                                         <br /><small class="text-muted">per item</small>
@@ -487,8 +487,8 @@
                                                         <strong class="text-success">@totalPowderNeeded.ToString("F2") lbs</strong>
                                                         <br /><small class="text-muted">total batch</small>
                                                     </td>
-                                                    <td>@item.UnitPrice.ToString("C")</td>
-                                                    <td><strong>@item.TotalPrice.ToString("C")</strong></td>
+                                                    <td><span data-inline-field="unitPrice" data-raw-value="@item.UnitPrice">@item.UnitPrice.ToString("C")</span></td>
+                                                    <td data-line-total><strong>@item.TotalPrice.ToString("C")</strong></td>
                                                 </tr>
                                             }
                                         </tbody>
@@ -1023,7 +1023,7 @@
 
                     <div class="d-flex justify-content-between mb-2">
                         <span>Subtotal:</span>
-                        <strong>@Model.PricingBreakdown.SubtotalBeforeDiscount.ToString("C")</strong>
+                        <strong id="quote-subtotal">@Model.PricingBreakdown.SubtotalBeforeDiscount.ToString("C")</strong>
                     </div>
 
                     @if (Model.PricingBreakdown.DiscountAmount > 0)
@@ -1075,7 +1075,7 @@
                     {
                         <div class="d-flex justify-content-between mb-2">
                             <span>Tax (@Model.PricingBreakdown.TaxPercent.ToString("G29")%):</span>
-                            <strong>@Model.PricingBreakdown.TaxAmount.ToString("C")</strong>
+                            <strong id="quote-tax">@Model.PricingBreakdown.TaxAmount.ToString("C")</strong>
                         </div>
                     }
 
@@ -1083,7 +1083,7 @@
 
                     <div class="d-flex justify-content-between mb-0">
                         <h5>Total:</h5>
-                        <h5 class="text-primary"><strong>@Model.Total.ToString("C")</strong></h5>
+                        <h5 class="text-primary"><strong id="quote-total">@Model.Total.ToString("C")</strong></h5>
                     </div>
 
                     @if (Model.PricingBreakdown.DiscountAmount > 0)
@@ -2262,6 +2262,18 @@
 
 @section Scripts {
     <script src="~/js/customer-change.js" asp-append-version="true"></script>
+    <script src="~/js/inline-item-edit.js" asp-append-version="true"></script>
+    <script>
+        window.inlineItemEdit = {
+            patchUrl: '@Url.Action("PatchItem", "Quotes")',
+            canEdit:  true,
+            totals: {
+                subtotal: '#quote-subtotal',
+                tax:      '#quote-tax',
+                total:    '#quote-total'
+            }
+        };
+    </script>
     <script>
         function sendQuoteToAdHocEmail(quoteId) {
             const email = (document.getElementById('quoteAdHocEmailInput').value ?? '').trim();

src/PowderCoating.Web/wwwroot/css/site.css

@@ -1152,3 +1152,14 @@ a.tag-index-badge:hover {
   }
 }
 .mw-lg { max-width: 640px; }
+
+/* ── Inline item edit ───────────────────────────────────────── */
+.inline-editable:hover {
+    text-decoration: underline dotted;
+    text-underline-offset: 3px;
+}
+.inline-edit-input {
+    display: inline-block;
+    padding: 1px 4px;
+    height: auto;
+}

src/PowderCoating.Web/wwwroot/js/inline-item-edit.js

@@ -0,0 +1,167 @@
+/// <summary>
+/// Shared inline-edit behaviour for quote, job, and invoice item rows.
+/// Activated when the page sets window.inlineItemEdit = { patchUrl, canEdit, totals }.
+/// totals: { subtotal, tax, total, finalPrice, balance } — CSS selectors, any subset.
+/// </summary>
+(function () {
+    'use strict';
+
+    const cfg = window.inlineItemEdit;
+    if (!cfg || !cfg.canEdit) return;
+
+    function fmt(val) {
+        return val.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
+    }
+
+    function csrfToken() {
+        return document.querySelector('input[name="__RequestVerificationToken"]')?.value ?? '';
+    }
+
+    function showError(msg) {
+        const el = document.createElement('div');
+        el.className = 'alert alert-danger alert-permanent position-fixed bottom-0 end-0 m-3 shadow';
+        el.style.zIndex = '9999';
+        el.textContent = msg;
+        document.body.appendChild(el);
+        setTimeout(() => el.remove(), 4000);
+    }
+
+    function updateTotals(data) {
+        const t = cfg.totals || {};
+        [
+            [t.subtotal,    data.subtotal],
+            [t.tax,         data.taxAmount],
+            [t.total,       data.total],
+            [t.finalPrice,  data.finalPrice],
+            [t.balance,     data.balanceDue],
+        ].forEach(([sel, val]) => {
+            if (sel && val !== undefined && val !== null) {
+                document.querySelectorAll(sel).forEach(el => { el.textContent = fmt(val); });
+            }
+        });
+    }
+
+    function makeEditable(span) {
+        const field = span.dataset.inlineField;
+        const row   = span.closest('tr[data-item-id]');
+        if (!row) return;
+        const itemId = row.dataset.itemId;
+
+        const rawVal = span.dataset.rawValue ?? span.textContent.trim();
+
+        const input = document.createElement('input');
+        input.className = 'form-control form-control-sm inline-edit-input';
+        if (field === 'description') {
+            input.type      = 'text';
+            input.style.minWidth = '140px';
+        } else {
+            input.type  = 'number';
+            input.step  = '0.01';
+            input.min   = '0';
+            input.style.width = '80px';
+        }
+        input.value = rawVal;
+
+        // Stash current rendered markup so we can revert
+        const savedHTML = span.innerHTML;
+        span.innerHTML = '';
+        span.appendChild(input);
+        input.focus();
+        input.select();
+
+        let committed = false;
+
+        function revert() {
+            span.innerHTML = savedHTML;
+            attachListeners(span);
+        }
+
+        async function commit() {
+            if (committed) return;
+            committed = true;
+
+            const newVal = input.value.trim();
+            if (newVal === '' || (field !== 'description' && isNaN(parseFloat(newVal)))) {
+                revert();
+                return;
+            }
+
+            // Read sibling raw values from other editable cells in the same row
+            function siblingRaw(f) {
+                const s = row.querySelector(`[data-inline-field="${f}"]`);
+                if (!s) return null;
+                // If that sibling is currently showing an input (concurrent edit, unlikely), fall back
+                const inp = s.querySelector('input.inline-edit-input');
+                if (inp) return inp.value;
+                return s.dataset.rawValue ?? s.textContent.trim();
+            }
+
+            const description = field === 'description' ? newVal : (siblingRaw('description') ?? '');
+            const quantity    = parseFloat(field === 'quantity'  ? newVal : (siblingRaw('quantity')  ?? '1'));
+            const unitPrice   = parseFloat(field === 'unitPrice' ? newVal : (siblingRaw('unitPrice') ?? '0'));
+
+            try {
+                const resp = await fetch(cfg.patchUrl, {
+                    method: 'POST',
+                    headers: {
+                        'Content-Type': 'application/json',
+                        'RequestVerificationToken': csrfToken()
+                    },
+                    body: JSON.stringify({ itemId: parseInt(itemId, 10), description, quantity, unitPrice })
+                });
+                if (!resp.ok) {
+                    const err = await resp.json().catch(() => ({}));
+                    showError(err.error ?? 'Could not save &mdash; try again.');
+                    revert();
+                    return;
+                }
+                const data = await resp.json();
+
+                // Update this span's display and stored raw value
+                if (field === 'description') {
+                    const strong = span.querySelector('strong');
+                    if (strong) { strong.textContent = newVal; }
+                    else        { span.innerHTML = `<strong>${newVal}</strong>`; }
+                    span.dataset.rawValue = newVal;
+                } else if (field === 'quantity') {
+                    span.dataset.rawValue = quantity;
+                    span.textContent = quantity % 1 === 0 ? quantity.toFixed(0) : quantity.toString();
+                } else if (field === 'unitPrice') {
+                    span.dataset.rawValue = unitPrice;
+                    span.textContent = fmt(unitPrice);
+                }
+
+                // Update line total cell
+                const totalCell = row.querySelector('[data-line-total]');
+                if (totalCell) totalCell.textContent = fmt(data.lineTotal);
+
+                // Update document-level totals
+                updateTotals(data);
+
+                // Re-attach click listener for next edit
+                attachListeners(span);
+
+            } catch {
+                showError('Could not save &mdash; check your connection and try again.');
+                revert();
+            }
+        }
+
+        input.addEventListener('blur', commit);
+        input.addEventListener('keydown', e => {
+            if (e.key === 'Enter')  { e.preventDefault(); input.blur(); }
+            if (e.key === 'Escape') { committed = true; revert(); }
+        });
+    }
+
+    function attachListeners(span) {
+        span.style.cursor = 'text';
+        span.title = 'Click to edit';
+        span.classList.add('inline-editable');
+        span.addEventListener('click', () => makeEditable(span), { once: true });
+    }
+
+    document.addEventListener('DOMContentLoaded', function () {
+        document.querySelectorAll('[data-inline-field]').forEach(attachListeners);
+    });
+})();