action sheet: Pull out fetchRawContentWithFeedback helper

Author: chrisbobbe

lib/widgets/action_sheet.dart

@@ -87,6 +87,53 @@ class ShareButton extends MessageActionSheetMenuItemButton {
   };
 }
 
+/// Fetch and return the raw Markdown content for [messageId],
+/// showing an error dialog on failure.
+Future<String?> fetchRawContentWithFeedback({
+  required BuildContext context,
+  required int messageId,
+  required String errorDialogTitle,
+}) async {
+    Message? fetchedMessage;
+    String? errorMessage;
+    // TODO, supported by reusable code:
+    // - (?) Retry with backoff on plausibly transient errors.
+    // - If request(s) take(s) a long time, show snackbar with cancel
+    //   button, like "Still working on quote-and-reply…".
+    //   On final failure or success, auto-dismiss the snackbar.
+    try {
+      fetchedMessage = await getMessageCompat(PerAccountStoreWidget.of(context).connection,
+        messageId: messageId,
+        applyMarkdown: false,
+      );
+      if (fetchedMessage == null) {
+        errorMessage = 'That message does not seem to exist.';
+      }
+    } catch (e) {
+      switch (e) {
+        case ZulipApiException():
+          errorMessage = e.message;
+        // TODO specific messages for common errors, like network errors
+        //   (support with reusable code)
+        default:
+          errorMessage = 'Could not fetch message source.';
+      }
+    }
+
+    if (!context.mounted) return null;
+
+    if (fetchedMessage == null) {
+      assert(errorMessage != null);
+      // TODO(?) give no feedback on error conditions we expect to
+      //   flag centrally in event polling, like invalid auth,
+      //   user/realm deactivated. (Support with reusable code.)
+      await showErrorDialog(context: context,
+        title: errorDialogTitle, message: errorMessage);
+    }
+
+    return fetchedMessage?.content;
+}
+
 class QuoteAndReplyButton extends MessageActionSheetMenuItemButton {
   QuoteAndReplyButton({
     super.key,
@@ -121,42 +168,11 @@ class QuoteAndReplyButton extends MessageActionSheetMenuItemButton {
         message: message,
       );
 
-    Message? fetchedMessage;
-    String? errorMessage;
-    // TODO, supported by reusable code:
-    // - (?) Retry with backoff on plausibly transient errors.
-    // - If request(s) take(s) a long time, show snackbar with cancel
-    //   button, like "Still working on quote-and-reply…".
-    //   On final failure or success, auto-dismiss the snackbar.
-    try {
-      fetchedMessage = await getMessageCompat(PerAccountStoreWidget.of(messageListContext).connection,
-        messageId: message.id,
-        applyMarkdown: false,
-      );
-      if (fetchedMessage == null) {
-        errorMessage = 'That message does not seem to exist.';
-      }
-    } catch (e) {
-      switch (e) {
-        case ZulipApiException():
-          errorMessage = e.message;
-        // TODO specific messages for common errors, like network errors
-        //   (support with reusable code)
-        default:
-          errorMessage = 'Could not fetch message source.';
-      }
-    }
-
-    if (!messageListContext.mounted) return;
-
-    if (fetchedMessage == null) {
-      assert(errorMessage != null);
-      // TODO(?) give no feedback on error conditions we expect to
-      //   flag centrally in event polling, like invalid auth,
-      //   user/realm deactivated. (Support with reusable code.)
-      await showErrorDialog(context: messageListContext,
-        title: 'Quotation failed', message: errorMessage);
-    }
+    final rawContent = await fetchRawContentWithFeedback(
+      context: messageListContext,
+      messageId: message.id,
+      errorDialogTitle: 'Quotation failed',
+    );
 
     if (!messageListContext.mounted) return;
 
@@ -167,7 +183,7 @@ class QuoteAndReplyButton extends MessageActionSheetMenuItemButton {
     composeBoxController.contentController
       .registerQuoteAndReplyEnd(PerAccountStoreWidget.of(messageListContext), tag,
         message: message,
-        rawContent: fetchedMessage?.content,
+        rawContent: rawContent,
       );
     if (!composeBoxController.contentFocusNode.hasFocus) {
       composeBoxController.contentFocusNode.requestFocus();