From 05bd0d0b671ad509465fa6cddabc3c2a07c796a7 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Mon, 20 Jul 2020 00:26:42 -0400
Subject: [PATCH 1/2] Add support for multiple Link as urls of Images in
 ActivityPub\Receiver

- Address https://github.com/friendica/friendica/issues/8676#issuecomment-650554955
---
 src/Protocol/ActivityPub/Receiver.php | 58 ++++++++++++++++++++++++++-
 1 file changed, 57 insertions(+), 1 deletion(-)

diff --git a/src/Protocol/ActivityPub/Receiver.php b/src/Protocol/ActivityPub/Receiver.php
index 7a0a9c1f78..aa59b9eb9e 100644
--- a/src/Protocol/ActivityPub/Receiver.php
+++ b/src/Protocol/ActivityPub/Receiver.php
@@ -877,7 +877,7 @@ class Receiver
 	 *
 	 * @param array $attachments Attachments in JSON-LD format
 	 *
-	 * @return array with attachmants in a simplified format
+	 * @return array Attachments in a simplified format
 	 */
 	private static function processAttachments(array $attachments)
 	{
@@ -925,6 +925,62 @@ class Receiver
 						'url' => JsonLD::fetchElement($attachment, 'as:href', '@id')
 					];
 					break;
+				case 'as:Image':
+					$mediaType = JsonLD::fetchElement($attachment, 'as:mediaType', '@value');
+					$imageFullUrl = JsonLD::fetchElement($attachment, 'as:url', '@id');
+					$imagePreviewUrl = null;
+					// Multiple URLs?
+					if (!$imageFullUrl && ($urls = JsonLD::fetchElementArray($attachment, 'as:url'))) {
+						$imageVariants = [];
+						$previewVariants = [];
+						foreach ($urls as $url) {
+							// Scalar URL, no discrimination possible
+							if (is_string($url)) {
+								$imageFullUrl = $url;
+								continue;
+							}
+
+							// Not sure what to do with a different Link media type than the base Image, we skip
+							if ($mediaType != JsonLD::fetchElement($url, 'as:mediaType', '@value')) {
+								continue;
+							}
+
+							$href = JsonLD::fetchElement($url, 'as:href', '@id');
+
+							// Default URL choice if no discriminating width is provided
+							$imageFullUrl = $href ?? $imageFullUrl;
+
+							$width = intval(JsonLD::fetchElement($url, 'as:width', '@value') ?? 1);
+
+							if ($href && $width) {
+								$imageVariants[$width] = $href;
+								// 632 is the ideal width for full screen frio posts, we compute the absolute distance to it
+								$previewVariants[abs(632 - $width)] = $href;
+							}
+						}
+
+						if ($imageVariants) {
+							// Taking the maximum size image
+							ksort($imageVariants);
+							$imageFullUrl = array_pop($imageVariants);
+
+							// Taking the minimum number distance to the target distance
+							ksort($previewVariants);
+							$imagePreviewUrl = array_shift($previewVariants);
+						}
+
+						unset($imageVariants);
+						unset($previewVariants);
+					}
+
+					$attachlist[] = [
+						'type' => str_replace('as:', '', JsonLD::fetchElement($attachment, '@type')),
+						'mediaType' => $mediaType,
+						'name'  => JsonLD::fetchElement($attachment, 'as:name', '@value'),
+						'url'   => $imageFullUrl,
+						'image' => $imagePreviewUrl !== $imageFullUrl ? $imagePreviewUrl : null,
+					];
+					break;
 				default:
 					$attachlist[] = [
 						'type' => str_replace('as:', '', JsonLD::fetchElement($attachment, '@type')),

From 3894976a2d7dd42784488d3ff3ddb7ff53c25bc1 Mon Sep 17 00:00:00 2001
From: Hypolite Petovan <hypolite@mrpetovan.com>
Date: Mon, 20 Jul 2020 00:27:36 -0400
Subject: [PATCH 2/2] Add support for image preview in attachments in
 ActivityPub\Processor

- Address https://github.com/friendica/friendica/issues/8676#issuecomment-650554955
---
 src/Protocol/ActivityPub/Processor.php | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/Protocol/ActivityPub/Processor.php b/src/Protocol/ActivityPub/Processor.php
index e4cef17045..177813e32d 100644
--- a/src/Protocol/ActivityPub/Processor.php
+++ b/src/Protocol/ActivityPub/Processor.php
@@ -115,10 +115,22 @@ class Processor
 							continue 2;
 						}
 
+						$item['body'] .= "\n";
+
+						// image is the preview/thumbnail URL
+						if (!empty($attach['image'])) {
+							$item['body'] .= '[url=' . $attach['url'] . ']';
+							$attach['url'] = $attach['image'];
+						}
+
 						if (empty($attach['name'])) {
-							$item['body'] .= "\n[img]" . $attach['url'] . '[/img]';
+							$item['body'] .= '[img]' . $attach['url'] . '[/img]';
 						} else {
-							$item['body'] .= "\n[img=" . $attach['url'] . ']' . $attach['name'] . '[/img]';
+							$item['body'] .= '[img=' . $attach['url'] . ']' . $attach['name'] . '[/img]';
+						}
+
+						if (!empty($attach['image'])) {
+							$item['body'] .= '[/url]';
 						}
 					} elseif ($filetype == 'audio') {
 						if (!empty($activity['source']) && strpos($activity['source'], $attach['url'])) {