AssetIterator: rewrite to standard Iterator interface

controllers/ViewPhotoAlbum.php

@@ -289,10 +289,4 @@ class ViewPhotoAlbum extends HTMLController
 		$description = !empty($tag->description) ? $tag->description : '';
 		return new AlbumHeaderBox($tag->tag, $description, $back_link, $back_link_title);
 	}
-
-	public function __destruct()
-	{
-		if (isset($this->iterator))
-			$this->iterator->clean();
-	}
 }

controllers/ViewTimeline.php

@@ -54,10 +54,4 @@ class ViewTimeline extends HTMLController
 		// Set the canonical url.
 		$this->page->setCanonicalUrl(BASEURL . '/timeline/');
 	}
-
-	public function __destruct()
-	{
-		if (isset($this->iterator))
-			$this->iterator->clean();
-	}
 }

models/Asset.php

@@ -24,7 +24,7 @@ class Asset
 	protected $tags;
 	protected $thumbnails;
 
-	protected function __construct(array $data)
+	public function __construct(array $data)
 	{
 		foreach ($data as $attribute => $value)
 		{

models/AssetIterator.php

@@ -1,42 +1,50 @@
 <?php
 /*****************************************************************************
  * AssetIterator.php
- * Contains key class AssetIterator.
+ * Contains model class AssetIterator.
  *
- * Kabuki CMS (C) 2013-2015, Aaron van Geffen
+ * Kabuki CMS (C) 2013-2025, Aaron van Geffen
  *****************************************************************************/
 
-class AssetIterator extends Asset
+class AssetIterator implements Iterator
 {
-	private Database $db;
 	private $direction;
-
 	private $return_format;
-	private $res_assets;
-	private $res_meta;
-	private $res_thumbs;
+	private $rowCount;
 
-	protected function __construct($res_assets, $res_meta, $res_thumbs, $return_format, $direction)
+	private $assets_iterator;
+	private $meta_iterator;
+	private $thumbs_iterator;
+
+	protected function __construct(PDOStatement $stmt_assets, PDOStatement $stmt_meta, PDOStatement $stmt_thumbs,
+		$return_format, $direction)
 	{
-		$this->db = Registry::get('db');
 		$this->direction = $direction;
-		$this->res_assets = $res_assets;
-		$this->res_meta = $res_meta;
-		$this->res_thumbs = $res_thumbs;
 		$this->return_format = $return_format;
+		$this->rowCount = $stmt_assets->rowCount();
+
+		$this->assets_iterator = new CachedPDOIterator($stmt_assets);
+		$this->assets_iterator->rewind();
+
+		$this->meta_iterator = new CachedPDOIterator($stmt_meta);
+		$this->thumbs_iterator = new CachedPDOIterator($stmt_thumbs);
 	}
 
-	public function next()
+	public static function all()
 	{
-		$row = $this->db->fetchAssoc($this->res_assets);
+		return self::getByOptions();
+	}
 
-		// No more rows?
+	public function current(): mixed
+	{
+		$row = $this->assets_iterator->current();
 		if (!$row)
-			return false;
+			return $row;
 
-		// Looks up metadata.
+		// Collect metadata
 		$row['meta'] = [];
-		while ($meta = $this->db->fetchAssoc($this->res_meta))
+		$this->meta_iterator->rewind();
+		foreach ($this->meta_iterator as $meta)
 		{
 			if ($meta['id_asset'] != $row['id_asset'])
 				continue;
@@ -44,54 +52,23 @@ class AssetIterator extends Asset
 			$row['meta'][$meta['variable']] = $meta['value'];
 		}
 
-		// Reset internal pointer for next asset.
-		$this->db->data_seek($this->res_meta, 0);
-
-		// Looks up thumbnails.
+		// Collect thumbnails
 		$row['thumbnails'] = [];
-		while ($thumbs = $this->db->fetchAssoc($this->res_thumbs))
+		$this->thumbs_iterator->rewind();
+		foreach ($this->thumbs_iterator as $thumb)
 		{
-			if ($thumbs['id_asset'] != $row['id_asset'])
+			if ($thumb['id_asset'] != $row['id_asset'])
 				continue;
 
-			$row['thumbnails'][$thumbs['selector']] = $thumbs['filename'];
+			$row['thumbnails'][$thumb['selector']] = $thumb['filename'];
 		}
 
-		// Reset internal pointer for next asset.
-		$this->db->data_seek($this->res_thumbs, 0);
-
 		if ($this->return_format === 'object')
 			return new Asset($row);
 		else
 			return $row;
 	}
 
-	public function reset()
-	{
-		$this->db->data_seek($this->res_assets, 0);
-		$this->db->data_seek($this->res_meta, 0);
-		$this->db->data_seek($this->res_thumbs, 0);
-	}
-
-	public function clean()
-	{
-		if (!$this->res_assets)
-			return;
-
-		$this->db->free($this->res_assets);
-		$this->res_assets = null;
-	}
-
-	public function num()
-	{
-		return $this->db->rowCount($this->res_assets);
-	}
-
-	public static function all()
-	{
-		return self::getByOptions();
-	}
-
 	public static function getByOptions(array $options = [], $return_count = false, $return_format = 'object')
 	{
 		$params = [
@@ -210,13 +187,38 @@ class AssetIterator extends Asset
 			return $iterator;
 	}
 
-	public function isAscending()
+	public function key(): mixed
+	{
+		return $this->assets_iterator->key();
+	}
+
+	public function isAscending(): bool
 	{
 		return $this->direction === 'asc';
 	}
 
-	public function isDescending()
+	public function isDescending(): bool
 	{
 		return $this->direction === 'desc';
 	}
+
+	public function next(): void
+	{
+		$this->assets_iterator->next();
+	}
+
+	public function num(): int
+	{
+		return $this->rowCount;
+	}
+
+	public function rewind(): void
+	{
+		$this->assets_iterator->rewind();
+	}
+
+	public function valid(): bool
+	{
+		return $this->assets_iterator->valid();
+	}
 }

models/PhotoMosaic.php

@@ -8,11 +8,11 @@
 
 class PhotoMosaic
 {
-	private $descending;
+	private bool $descending;
 	private AssetIterator $iterator;
-	private $layouts;
-	private $processedImages = 0;
-	private $queue = [];
+	private array $layouts;
+	private int $processedImages = 0;
+	private array $queue = [];
 
 	const IMAGE_MASK_ALL = Image::TYPE_PORTRAIT | Image::TYPE_LANDSCAPE | Image::TYPE_PANORAMA;
 	const NUM_DAYS_CUTOFF = 7;
@@ -25,11 +25,6 @@ class PhotoMosaic
 		$this->descending = $iterator->isDescending();
 	}
 
-	public function __destruct()
-	{
-		$this->iterator->clean();
-	}
-
 	private function availableLayouts()
 	{
 		static $layouts = [
@@ -86,9 +81,14 @@ class PhotoMosaic
 			}
 		}
 
-		// Check whatever's next up!
-		while (($asset = $this->iterator->next()) && ($image = $asset->getImage()))
+		// Check whatever's up next!
+		// NB: not is not a `foreach` so as to not reset the iterator implicitly
+		while ($this->iterator->valid())
 		{
+			$asset = $this->iterator->current();
+			$image = $asset->getImage();
+			$this->iterator->next();
+
 			// Give up on the recordset once dates are too far apart
 			if (isset($refDate) && abs(self::daysApart($image->getDateCaptured(), $refDate)) > self::NUM_DAYS_CUTOFF)
 			{

templates/FeaturedThumbnailManager.php

@@ -8,12 +8,12 @@
 
 class FeaturedThumbnailManager extends SubTemplate
 {
-	private $assets;
+	private $iterator;
 	private $currentThumbnailId;
 
-	public function __construct(AssetIterator $assets, $currentThumbnailId)
+	public function __construct(AssetIterator $iterator, $currentThumbnailId)
 	{
-		$this->assets = $assets;
+		$this->iterator = $iterator;
 		$this->currentThumbnailId = $currentThumbnailId;
 	}
 
@@ -25,7 +25,7 @@ class FeaturedThumbnailManager extends SubTemplate
 			<h2>Select thumbnail</h2>
 			<ul id="featuredThumbnail">';
 
-		while ($asset = $this->assets->next())
+		foreach ($this->iterator as $asset)
 		{
 			$image = $asset->getImage();
 			echo '
@@ -36,8 +36,6 @@ class FeaturedThumbnailManager extends SubTemplate
 				</li>';
 		}
 
-		$this->assets->clean();
-
 		echo '
 				</ul>
 				<input type="hidden" name="', Session::getSessionTokenKey(), '" value="', Session::getSessionToken(), '">