generic API response + ICS: warehouse_balance md_rack update

app/assets/js/custom.js

@@ -401,12 +401,34 @@ function ajax_request(options) {
     isAjaxProcessing = false;
     $.LoadingOverlay("hide");
 
+    // Errors re-thrown from .then() — pass through
     if (xhr instanceof Error) {
       throw xhr;
     }
 
-    console.error("AJAX Error:", xhr?.responseText);
-    bootbox.alert("Server error occurred.");
+    // Extract server's error message from JSON response
+    let serverMessage = xhr?.responseJSON?.message;
+
+    // Fallback: parse responseText if responseJSON isn't set
+    if (!serverMessage && xhr?.responseText) {
+      try {
+        serverMessage = JSON.parse(xhr.responseText)?.message;
+      } catch (e) {
+        // Response wasn't JSON — real server crash or HTML error page
+      }
+    }
+
+    if (serverMessage) {
+      // Known server-reported error (HTTP 4xx/5xx with JSON body)
+      bootbox.alert(serverMessage);
+      options.onError?.(xhr, serverMessage);
+    } else {
+      // Unknown error — network failure, PHP fatal, HTML error page
+      console.error("AJAX Error:", xhr?.status, xhr?.responseText);
+      bootbox.alert("Server error occurred.");
+      options.onError?.(xhr, null);
+    }
+
     throw xhr;
   });
 }
@@ -422,6 +444,7 @@ function generate_pagination(table_id, total_records, records_per_page, current_
   // 1. Find the table and thead
   const table = document.getElementById(table_id);
   let theme_class = '';
+  let col_count = 1;
 
   if (table) {
     const thead = table.querySelector('thead');
@@ -433,16 +456,25 @@ function generate_pagination(table_id, total_records, records_per_page, current_
         // 3. Convert "table-secondary" to "page-item-secondary"
         theme_class = bootstrap_theme.replace('table-', 'page-item-');
       }
+
+      // 4. Count <th> in the first row of thead
+      const header_row = thead.querySelector('tr');
+      if (header_row) {
+        col_count = header_row.querySelectorAll('th').length || 1;
+      }
     }
   }
 
+  const left_span = Math.floor(col_count / 2);
+  const right_span = Math.ceil(col_count / 2);
+
   let pagination_html = `
     <tr>
-      <td class="border-bottom-0">
+      <td colspan="${left_span}" class="border-bottom-0">
         <span class="text-muted">Showing ${records_per_page} per page</span><br>
         <strong>Total: ${total_records}</strong>
       </td>
-      <td colspan="9" class="border-bottom-0">
+      <td colspan="${right_span}" class="border-bottom-0">
         <nav aria-label="Page navigation" class="d-flex justify-content-end">
           <ul class="pagination mb-0">`;