From 39c31dadfac814b521aaa5b018163a3e26752c6b Mon Sep 17 00:00:00 2001
From: Dev <dev@sharepoint-toolbox.local>
Date: Tue, 7 Apr 2026 15:21:02 +0200
Subject: [PATCH] feat(09-01): extend IStorageService with
 CollectFileTypeMetricsAsync

- Add CollectFileTypeMetricsAsync method signature to IStorageService
- Returns IReadOnlyList<FileTypeMetric> for chart visualization data
- Existing CollectStorageAsync signature unchanged
- CS0535 expected until StorageService implements in Plan 09-02

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 SharepointToolbox/Services/IStorageService.cs | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/SharepointToolbox/Services/IStorageService.cs b/SharepointToolbox/Services/IStorageService.cs
index 16143d6..c538904 100644
--- a/SharepointToolbox/Services/IStorageService.cs
+++ b/SharepointToolbox/Services/IStorageService.cs
@@ -5,9 +5,25 @@ namespace SharepointToolbox.Services;
 
 public interface IStorageService
 {
+    /// <summary>
+    /// Collects storage metrics per library/folder using SharePoint StorageMetrics API.
+    /// Returns a tree of StorageNode objects with aggregate size data.
+    /// </summary>
     Task<IReadOnlyList<StorageNode>> CollectStorageAsync(
         ClientContext ctx,
         StorageScanOptions options,
         IProgress<OperationProgress> progress,
         CancellationToken ct);
+
+    /// <summary>
+    /// Enumerates files across all non-hidden document libraries in the site
+    /// and aggregates storage consumption grouped by file extension.
+    /// Uses CSOM CamlQuery to retrieve FileLeafRef and File_x0020_Size per file.
+    /// This is a separate operation from CollectStorageAsync -- it provides
+    /// file-type breakdown data for chart visualization.
+    /// </summary>
+    Task<IReadOnlyList<FileTypeMetric>> CollectFileTypeMetricsAsync(
+        ClientContext ctx,
+        IProgress<OperationProgress> progress,
+        CancellationToken ct);
 }