Group export feeds by category (#9079)

* Group export feeds by category

## What changed
- Groups feed choices in the import/export page by their existing FreshRSS category.
- Preserves the current export request format and selection behavior.

## Why
The export selector previously mixed feeds from every category, making a category-specific export difficult to assemble.

Closes #5555

* Declare export feed count view data

* Fix select size

---------

Co-authored-by: Gerard Alvear <gerard.alvear@logiqd.me>
Co-authored-by: Alexandre Alapetite <alexandre@alapetite.fr>

app/Controllers/importExportController.php

@@ -32,7 +32,8 @@ class FreshRSS_importExport_Controller extends FreshRSS_ActionController {
 	 * This action displays the main page for import / export system.
 	 */
 	public function indexAction(): void {
-		$this->view->feeds = $this->feedDAO->listFeeds();
+		$this->view->categories = $this->categoryDAO->listCategories();
+		$this->view->feedCount = array_sum(array_map(static fn(FreshRSS_Category $category): int => count($category->feeds()), $this->view->categories));
 		FreshRSS_View::prependTitle(_t('sub.import_export.title') . ' · ');
 		$this->listSqliteArchives();
 	}

app/Models/View.php

@@ -91,6 +91,7 @@ class FreshRSS_View extends Minz_View {
 
 	// Export / Import
 	public string $content;
+	public int $feedCount;
 	/** @var array<string,array<string>> */
 	public array $entryIdsTagNames = [];
 	public string $list_title;

app/views/importExport/index.phtml

@@ -35,7 +35,7 @@
 	</form>
 
 	<h2><?= _t('sub.import_export.export') ?></h2>
-	<?php if (count($this->feeds) > 0) { ?>
+	<?php if ($this->feedCount > 0) { ?>
 	<form method="post" action="<?= _url('importExport', 'export') ?>" data-auto-leave-validation="1">
 		<input type="hidden" name="_csrf" value="<?= FreshRSS_Auth::csrfToken() ?>" />
 		<div class="form-group">
@@ -58,14 +58,23 @@
 				<?php
 					$select_args = '';
 					if (extension_loaded('zip')) {
-						$select_args = ' size="' . min(10, count($this->feeds)) . '" multiple="multiple"';
+						$select_args = ' size="' . min(10, count($this->categories) + $this->feedCount) . '" multiple="multiple"';
 					}
 				?>
 				<select name="export_feeds[]"<?= $select_args ?>>
 					<?= extension_loaded('zip') ? '' : '<option></option>' ?>
-					<?php foreach ($this->feeds as $feed) { ?>
-					<option value="<?= $feed->id() ?>"><?= $feed->name() ?></option>
-					<?php } ?>
+					<?php foreach ($this->categories as $category):
+						$feeds = $category->feeds();
+						if (empty($feeds)) {
+							continue;
+						}
+					?>
+					<optgroup label="<?= $category->name() ?>">
+						<?php foreach ($feeds as $feed) { ?>
+						<option value="<?= $feed->id() ?>"><?= $feed->name() ?></option>
+						<?php } ?>
+					</optgroup>
+					<?php endforeach; ?>
 				</select>
 			</div>
 		</div>