Improve theme infra of BitFileUpload (#13323)

src/BlazorUI/Bit.BlazorUI/Components/Inputs/FileUpload/BitFileInfo.cs

@@ -32,7 +32,8 @@ public class BitFileInfo
     [JsonPropertyName("fileId")] public string FileId { get; set; } = string.Empty;
 
     /// <summary>
-    /// The index of the selected file.
+    /// The index of the file among the ones picked in this browser, which is what names the transfer behind
+    /// it. A preloaded file was never picked and has no transfer of its own, so its index is -1.
     /// </summary>
     [JsonPropertyName("index")] public int Index { get; set; }
 
@@ -95,6 +96,14 @@ public class BitFileInfo
     /// </summary>
     [JsonIgnore] public bool IsQueued { get; internal set; }
 
+    /// <summary>
+    /// Whether the file was handed over through the PreloadedFiles parameter of the BitFileUpload instead of
+    /// being picked in the browser, which is to say it is already on the server: there is no content on this
+    /// side to send, so it is never uploaded, and removing it deletes it from the server through the
+    /// RemoveUrl exactly like a file whose bytes got there through this component.
+    /// </summary>
+    [JsonIgnore] public bool IsPreloaded { get; internal set; }
+
 
     // Whether a request of this file is on the wire right now. A second request for the same file would
     // take over the connection of the first one and start it over from the beginning, so a repeated
@@ -128,9 +137,19 @@ public class BitFileInfo
     /// <summary>
     /// The message attached to the current <see cref="Status"/> of the file: the reason it was rejected by
     /// the validations before the upload, or the body of the server response of its upload or removal.
+    /// A response body is truncated to its first 8 KB, since it crosses the Blazor Server circuit, whose
+    /// default message size limit an error page of a failing endpoint would otherwise exceed.
     /// </summary>
     [JsonIgnore] public string? Message { get; internal set; }
 
+    /// <summary>
+    /// The HTTP status code of the last upload or removal response this file received, which is what tells
+    /// an authorization problem from a payload that was too large or from a server that is temporarily down.
+    /// It is 0 when the request never reached the server at all - a network error, a timeout or an abort -
+    /// and null while no request of this file has come back yet.
+    /// </summary>
+    [JsonIgnore] public int? ResponseStatus { get; internal set; }
+
     /// <summary>
     /// The status of the file in the BitFileUpload.
     /// </summary>

src/BlazorUI/Bit.BlazorUI/Components/Inputs/FileUpload/BitFileUpload.razor

@@ -13,14 +13,22 @@
     }
     else if (_ShowLabelButton)
     {
-        <button @onclick="Browse"
+        <button @ref="_labelRef"
+                @onclick="Browse"
                 type="button"
                 id="@_buttonId"
                 disabled="@(IsEnabled is false)"
                 aria-label="@AriaLabel"
                 aria-describedby="@(_HasDescription ? _descriptionId : null)"
                 style="@Styles?.Label"
                 class="bit-upl-lbl @Classes?.Label">
+            @* the drop area is the one place a label reads better with a glyph than without, so it brings one
+               of its own; anywhere else the icon is opt-in. the text beside it already names the button. *@
+            @{ var labelIcon = BitIconInfo.From(LabelIcon, LabelIconName ?? (ShowDropArea ? "CloudUpload" : null)); }
+            @if (labelIcon is { IsEmpty: false })
+            {
+                <i style="@Styles?.LabelIcon" class="bit-upl-lic @labelIcon.GetCssClasses() @Classes?.LabelIcon" aria-hidden="true" />
+            }
             @Label
         </button>
     }
@@ -57,7 +65,12 @@
        away with them rather than staying behind as an empty landmark in the accessibility tree. *@
     @if (HideFileView is false && Files.Any(f => f.Status != BitFileUploadStatus.Removed))
     {
-        <div role="list" style="@Styles?.FileList" class="bit-upl-fl @Classes?.FileList">
+        @* the list is named, so that a screen reader user arriving at it is told what it holds rather than
+           only that it is a list of so many items. *@
+        <div role="list"
+             aria-label="@(FileListAriaLabel.HasValue() ? FileListAriaLabel : null)"
+             style="@Styles?.FileList"
+             class="bit-upl-fl @Classes?.FileList">
             @* a removed file is not part of the list anymore, so it is left out of it here rather than
                leaving an empty listitem behind for a custom template that renders nothing for it. *@
             @foreach (var file in Files.Where(f => f.Status != BitFileUploadStatus.Removed))
@@ -77,5 +90,45 @@
         </div>
     }
 
+    @* the batch buttons stay where they are for as long as the list has files picked here, and the ones with
+       nothing to act on right now are marked aria-disabled rather than taken out or natively disabled: the
+       state changes on its own as uploads settle, and a focused button that vanished - or turned disabled -
+       under the keyboard would drop the focus on the document body. *@
+    @if (ShowBatchActions && _HasPickedFiles)
+    {
+        var canUploadAll = _CanUploadAll;
+        var canCancelAll = _CanCancelAll;
+        var canClear = _CanClear;
+        <div style="@Styles?.BatchActions" class="bit-upl-bat @Classes?.BatchActions">
+            @if (AutoUpload is false)
+            {
+                <button @onclick="HandleUploadAll"
+                        type="button"
+                        disabled="@(IsEnabled is false)"
+                        aria-disabled="@(canUploadAll ? null : "true")"
+                        style="@Styles?.BatchActionButton"
+                        class="bit-upl-bab @Classes?.BatchActionButton">
+                    @UploadAllText
+                </button>
+            }
+            <button @onclick="HandleCancelAll"
+                    type="button"
+                    disabled="@(IsEnabled is false)"
+                    aria-disabled="@(canCancelAll ? null : "true")"
+                    style="@Styles?.BatchActionButton"
+                    class="bit-upl-bab @Classes?.BatchActionButton">
+                @CancelAllText
+            </button>
+            <button @onclick="HandleClear"
+                    type="button"
+                    disabled="@(IsEnabled is false)"
+                    aria-disabled="@(canClear ? null : "true")"
+                    style="@Styles?.BatchActionButton"
+                    class="bit-upl-bab @Classes?.BatchActionButton">
+                @ClearText
+            </button>
+        </div>
+    }
+
     <div role="status" aria-live="polite" aria-atomic="true" class="bit-upl-lvr">@_announcement</div>
 </div>