feat(channels): implement PayloadPreviewModal side-by-side JSON inspector and Preview Transformed Payload button

src/features/channels/api/channels.api.ts

@@ -54,6 +54,11 @@ export const channelsApi = {
     const res = await apiClient.get<ApiResponse<any[]>>(`${BASE_URL}/${channelId}/jobs`);
     return res.data || [];
   },
+
+  previewPayload: async (channelId: string): Promise<any> => {
+    const res = await apiClient.post<ApiResponse<any>>(`${BASE_URL}/${channelId}/preview`);
+    return res.data;
+  },
 };
 
 export default channelsApi;

src/features/channels/components/ChannelMappingTab.tsx

@@ -1,8 +1,9 @@
 import { useState, useEffect } from "react";
-import { Save, Plus, Trash2, ArrowRight } from "lucide-react";
+import { Save, Plus, Trash2, ArrowRight, Eye } from "lucide-react";
 import { Button } from "../../../components/customs/Button";
 import { channelsApi } from "../api/channels.api";
 import { notify } from "../../../services/toast";
+import { PayloadPreviewModal } from "./PayloadPreviewModal";
 
 const COMMON_PIM_ATTRIBUTES = [
   { code: "name", label: "Product Title / Name (name)" },
@@ -34,6 +35,8 @@ export function ChannelMappingTab({ channelId }: { channelId: string }) {
   const [mappings, setMappings] = useState<any[]>([]);
   const [loading, setLoading] = useState(true);
   const [saving, setSaving] = useState(false);
+  const [previewing, setPreviewing] = useState(false);
+  const [previewData, setPreviewData] = useState<any>(null);
 
   useEffect(() => {
     loadMappings();
@@ -93,6 +96,18 @@ export function ChannelMappingTab({ channelId }: { channelId: string }) {
     }
   };
 
+  const handlePreview = async () => {
+    setPreviewing(true);
+    try {
+      const data = await channelsApi.previewPayload(channelId);
+      setPreviewData(data);
+    } catch {
+      notify.error("Failed to generate transformation preview");
+    } finally {
+      setPreviewing(false);
+    }
+  };
+
   if (loading) {
     return (
       <div className="flex items-center justify-center h-48">
@@ -109,6 +124,9 @@ export function ChannelMappingTab({ channelId }: { channelId: string }) {
           <p className="text-xs text-muted-foreground mt-0.5">Map central PIM attributes to target storefront fields and apply transformation pipelines.</p>
         </div>
         <div className="flex items-center gap-2">
+          <Button variant="outline" loading={previewing} onClick={handlePreview}>
+            <Eye className="w-4 h-4 mr-2" /> Preview Transformed Payload
+          </Button>
           <Button variant="outline" onClick={handleAddRule}>
             <Plus className="w-4 h-4 mr-2" /> Add Rule
           </Button>
@@ -118,6 +136,12 @@ export function ChannelMappingTab({ channelId }: { channelId: string }) {
         </div>
       </div>
 
+      <PayloadPreviewModal
+        isOpen={Boolean(previewData)}
+        onClose={() => setPreviewData(null)}
+        previewData={previewData}
+      />
+
       <div className="border border-border rounded-lg overflow-hidden bg-surface shadow-sm">
         <table className="w-full text-left text-sm">
           <thead className="bg-surface-muted border-b border-border text-xs text-muted-foreground uppercase">

src/features/channels/components/PayloadPreviewModal.tsx

@@ -0,0 +1,84 @@
+import { Button } from "../../../components/customs/Button";
+import { Code, Check, Copy } from "lucide-react";
+import { useState } from "react";
+
+interface PayloadPreviewModalProps {
+  isOpen: boolean;
+  onClose: () => void;
+  previewData: any;
+}
+
+export function PayloadPreviewModal({ isOpen, onClose, previewData }: PayloadPreviewModalProps) {
+  const [copied, setCopied] = useState(false);
+
+  if (!isOpen || !previewData) return null;
+
+  const handleCopy = () => {
+    navigator.clipboard.writeText(JSON.stringify(previewData.adapterOutput, null, 2));
+    setCopied(true);
+    setTimeout(() => setCopied(false), 2000);
+  };
+
+  return (
+    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/60 p-4">
+      <div className="bg-surface border border-border rounded-xl shadow-2xl max-w-4xl w-full flex flex-col max-h-[85vh] overflow-hidden">
+        {/* Header */}
+        <div className="px-6 py-4 border-b border-border bg-gradient-to-r from-primary/10 to-surface flex items-center justify-between">
+          <div className="flex items-center gap-3">
+            <div className="w-8 h-8 rounded-lg bg-primary/10 flex items-center justify-center text-primary">
+              <Code className="w-4 h-4" />
+            </div>
+            <div>
+              <h3 className="font-semibold text-foreground text-sm">Transformed Payload Preview</h3>
+              <p className="text-xs text-muted-foreground">Real-time adapter transformation preview for channel: <span className="font-semibold text-primary">{previewData.channel?.name}</span></p>
+            </div>
+          </div>
+          <button
+            onClick={onClose}
+            className="text-muted-foreground hover:text-foreground text-sm font-bold p-1 rounded"
+          >
+            ✕
+          </button>
+        </div>
+
+        {/* Content */}
+        <div className="p-6 grid grid-cols-2 gap-4 flex-1 overflow-y-auto">
+          {/* Left Column: PIM Raw Data */}
+          <div className="flex flex-col border border-border rounded-lg bg-surface-muted overflow-hidden">
+            <div className="px-3 py-2 bg-border/40 text-xs font-semibold text-muted-foreground uppercase tracking-wider border-b border-border">
+              PIM Central Product (Raw JSON)
+            </div>
+            <pre className="p-4 text-xs font-mono text-foreground overflow-auto flex-1 max-h-96">
+              {JSON.stringify(previewData.pimProductRaw, null, 2)}
+            </pre>
+          </div>
+
+          {/* Right Column: Adapter Storefront Output */}
+          <div className="flex flex-col border border-primary/20 rounded-lg bg-primary/5/30 overflow-hidden">
+            <div className="px-3 py-2 bg-primary/10 text-xs font-semibold text-primary uppercase tracking-wider border-b border-primary/20 flex justify-between items-center">
+              <span>Adapter Storefront Payload ({previewData.channel?.code})</span>
+              <button
+                type="button"
+                onClick={handleCopy}
+                className="inline-flex items-center gap-1 text-[11px] text-primary hover:underline"
+              >
+                {copied ? <Check className="w-3 h-3 text-success" /> : <Copy className="w-3 h-3" />}
+                {copied ? "Copied!" : "Copy Payload"}
+              </button>
+            </div>
+            <pre className="p-4 text-xs font-mono text-primary-dark overflow-auto flex-1 max-h-96">
+              {JSON.stringify(previewData.adapterOutput, null, 2)}
+            </pre>
+          </div>
+        </div>
+
+        {/* Footer */}
+        <div className="px-6 py-3 border-t border-border bg-surface-muted flex justify-end gap-2">
+          <Button variant="outline" onClick={onClose}>
+            Close Inspector
+          </Button>
+        </div>
+      </div>
+    </div>
+  );
+}