From acdef62880bfd56f16b08b8fa30d682521418c9c Mon Sep 17 00:00:00 2001
From: N-Pex <npexdev@gmail.com>
Date: Thu, 19 Jun 2025 10:58:11 +0200
Subject: [PATCH] Fix gallery view and lazy load thumbnails

---
 src/assets/css/sendattachments.scss           |  4 +--
 src/components/file_mode/GalleryItemsView.vue | 16 +++++----
 .../messages/MessageIncomingImage.vue         | 14 ++++++--
 .../messages/MessageOutgoingImage.vue         | 14 ++++++--
 .../composition/MessageIncomingThread.vue     | 34 ++++++++++++-------
 .../composition/MessageOutgoingThread.vue     | 14 ++++++--
 6 files changed, 69 insertions(+), 27 deletions(-)

diff --git a/src/assets/css/sendattachments.scss b/src/assets/css/sendattachments.scss
index 70e4c49..51a8cde 100644
--- a/src/assets/css/sendattachments.scss
+++ b/src/assets/css/sendattachments.scss
@@ -73,7 +73,7 @@ $hiliteColor: #4642f1;
     color: rgba($text, 80%) !important;
   }
 
-  .send-attachments__selecting__current-item {
+  .send-attachments__selecting__current-item, .gallery-current-item {
     width: 100%;
     flex: 1 1 100%;
     background-color: $backgroundSection;
@@ -102,7 +102,7 @@ $hiliteColor: #4642f1;
     }
   }
 
-  .file-drop-thumbnail-container {
+  .file-drop-thumbnail-container, .gallery-thumbnail-container {
     width: 100%;
     padding: 13px 20px 15px 20px;
     flex: 0 0 74px;
diff --git a/src/components/file_mode/GalleryItemsView.vue b/src/components/file_mode/GalleryItemsView.vue
index 4414f85..82dd87e 100644
--- a/src/components/file_mode/GalleryItemsView.vue
+++ b/src/components/file_mode/GalleryItemsView.vue
@@ -1,5 +1,5 @@
 <template>
-  <div class="fill-screen file-drop-root">
+  <div class="fill-screen send-attachments">
 
     <div class="chat-header">
       <v-container fluid class="d-flex justify-space-between align-center">
@@ -9,13 +9,13 @@
       </v-container>
     </div>
 
-    <div class="file-drop-current-item">
+    <div class="gallery-current-item">
       <ThumbnailView :item="items[currentItemIndex]" />
       <div class="download-button clickable" @click.stop="downloadOne">
           <v-icon color="black">arrow_downward</v-icon>
       </div>
     </div>
-    <div class="file-drop-thumbnail-container">
+    <div class="gallery-thumbnail-container">
       <div :class="{ 'file-drop-thumbnail': true, 'clickable': true, 'current': id == currentItemIndex }"
         @click="currentItemIndex = id" v-for="(currentImageInput, id) in items" :key="id">
         <v-img v-if="currentImageInput" :src="currentImageInput.thumbnail ? currentImageInput.thumbnail : currentImageInput.src" />
@@ -107,15 +107,17 @@ export default {
 
 <style lang="scss">
 @use "@/assets/css/chat.scss" as *;
+@use "@/assets/css/sendattachments.scss" as *;
 
 .chat-header {
   position: relative !important;
   width: 100%;
+  flex: 0 0 auto;
 }
 
-.file-drop-current-item {
-  position: relative;
-}
+// .file-drop-current-item {
+//   position: relative;
+// }
 
 .download-button {
   position: absolute;
@@ -137,7 +139,7 @@ export default {
     right: 0;
     bottom: 0;
     background: black;
-    z-index: 20;
+    z-index: 20 !important;
     justify-content: space-between !important;
 }
 </style>
\ No newline at end of file
diff --git a/src/components/messages/MessageIncomingImage.vue b/src/components/messages/MessageIncomingImage.vue
index 16e4e40..29a7422 100644
--- a/src/components/messages/MessageIncomingImage.vue
+++ b/src/components/messages/MessageIncomingImage.vue
@@ -1,5 +1,5 @@
 <template>
-  <message-incoming v-bind="{ ...$props, ...$attrs }">
+  <message-incoming v-bind="{ ...$props, ...$attrs }" v-intersect="onIntersect">
     <div class="bubble image-bubble" ref="imageRef">
       <ImageWithProgress
         :aspect-ratio="16 / 9"
@@ -30,6 +30,7 @@ export default {
       cover: true,
       contain: false,
       dialog: false,
+      isVisible: false,
     };
   },
   methods: {
@@ -44,6 +45,15 @@ export default {
         }
       });
     },
+    loadThumbnail() {
+      if (this.isVisible) {
+         this.eventAttachment?.loadThumbnail();
+      }
+    },
+    onIntersect(isIntersecting, entries, observer) {
+      this.isVisible = isIntersecting;
+      this.loadThumbnail();
+    }
   },
   mounted() {
     //console.log("Mounted with event:", JSON.stringify(this.event.getContent()));
@@ -62,7 +72,7 @@ export default {
     }
 
     this.eventAttachment = this.$matrix.attachmentManager.getEventAttachment(this.event);
-    this.eventAttachment?.loadThumbnail();
+    this.loadThumbnail();
   },
   beforeUnmount() {
     this.eventAttachment?.release();
diff --git a/src/components/messages/MessageOutgoingImage.vue b/src/components/messages/MessageOutgoingImage.vue
index 6b8fe4e..e4fd272 100644
--- a/src/components/messages/MessageOutgoingImage.vue
+++ b/src/components/messages/MessageOutgoingImage.vue
@@ -1,5 +1,5 @@
 <template>
-  <message-outgoing v-bind="{ ...$props, ...$attrs }">
+  <message-outgoing v-bind="{ ...$props, ...$attrs }" v-intersect="onIntersect">
     <div class="bubble image-bubble" ref="imageRef">
       <ImageWithProgress
         :aspect-ratio="16 / 9"
@@ -30,6 +30,7 @@ export default {
       cover: true,
       contain: false,
       dialog: false,
+      isVisible: false,
     };
   },
   methods: {
@@ -44,6 +45,15 @@ export default {
         }
       });
     },
+    loadThumbnail() {
+      if (this.isVisible) {
+         this.eventAttachment?.loadThumbnail();
+      }
+    },
+    onIntersect(isIntersecting, entries, observer) {
+      this.isVisible = isIntersecting;
+      this.loadThumbnail();
+    }
   },
   mounted() {
     console.error("Mounted outgoing image, load thumbnail!");
@@ -62,7 +72,7 @@ export default {
       this.initMessageOutImageHammerJs(this.$refs.imageRef);
     }
     this.eventAttachment = this.$matrix.attachmentManager.getEventAttachment(this.event);
-    this.eventAttachment?.loadThumbnail();
+    this.loadThumbnail();
   },
   beforeUnmount() {
     this.eventAttachment?.release();
diff --git a/src/components/messages/composition/MessageIncomingThread.vue b/src/components/messages/composition/MessageIncomingThread.vue
index c242981..131c4bd 100644
--- a/src/components/messages/composition/MessageIncomingThread.vue
+++ b/src/components/messages/composition/MessageIncomingThread.vue
@@ -3,6 +3,7 @@
     ref="root"
     v-bind="{ ...$props, ...$attrs }"
     v-if="showMultiview"
+    v-intersect="onIntersect"
   >
     <div class="bubble">
       <div class="original-message" v-if="inReplyToText">
@@ -74,6 +75,7 @@ const emits = defineEmits<MessageEmits & {(event: "layout-change", value: {eleme
 
 const items: Ref<EventAttachment[]> = ref([]);
 const showItem: Ref<EventAttachment | undefined> = ref(undefined);
+const isVisible: Ref<boolean> = ref(false);
 
 const props = defineProps<MessageProps>();
 
@@ -96,6 +98,17 @@ const {
   linkify,
 } = useMessage($matrix, t, props, emits, processThread);
 
+const onRelationsCreated = () => {
+  if (event.value) {
+    thread.value = props.timelineSet.relations.getChildEventsForEvent(
+      event.value.getId() ?? "",
+      util.threadMessageType(),
+      "m.room.message"
+    );
+    event.value.off(MatrixEventEvent.RelationsCreated, onRelationsCreated);
+  }
+};
+
 watch(event, () => {
   if (event.value) {
     if (thread.value === undefined) {
@@ -123,17 +136,6 @@ const showMultiview = computed((): boolean => {
     messageText.value?.length > 0
 });
 
-const onRelationsCreated = () => {
-  if (event.value) {
-    thread.value = props.timelineSet.relations.getChildEventsForEvent(
-      event.value.getId() ?? "",
-      util.threadMessageType(),
-      "m.room.message"
-    );
-    event.value.off(MatrixEventEvent.RelationsCreated, onRelationsCreated);
-  }
-};
-
 const onItemClick = (event: any) => {
   showItem.value = event.item;
 };
@@ -145,7 +147,7 @@ const _processThread = () => {
 
   items.value = eventItems.map((e: MatrixEvent) => {
     let ea = $matrix.attachmentManager.getEventAttachment(e);
-    if (showMultiview.value) {
+    if (showMultiview.value && isVisible.value) {
       ea.loadThumbnail();
     }
     return ea;
@@ -184,6 +186,14 @@ const layoutedItems = computed(() => {
   }
   return rows;
 });
+
+const onIntersect = (isIntersecting: boolean, entries: any, observer: any) => {
+  isVisible.value = isIntersecting;
+  if (showMultiview.value && isIntersecting) {
+    items.value.forEach((a) => a.loadThumbnail());
+  }
+};
+
 </script>
 <style lang="scss">
 @use "@/assets/css/chat.scss" as *;
diff --git a/src/components/messages/composition/MessageOutgoingThread.vue b/src/components/messages/composition/MessageOutgoingThread.vue
index 55eefb9..6fcd8fd 100644
--- a/src/components/messages/composition/MessageOutgoingThread.vue
+++ b/src/components/messages/composition/MessageOutgoingThread.vue
@@ -3,6 +3,7 @@
     ref="root"
     v-bind="{ ...$props, ...$attrs }"
     v-if="showMultiview"
+    v-intersect="onIntersect"
   >
     <div class="bubble">
       <div class="original-message" v-if="inReplyToText">
@@ -74,7 +75,8 @@ const emits = defineEmits<MessageEmits & {(event: "layout-change", value: {eleme
 
 const items: Ref<EventAttachment[]> = ref([]);
 const showItem: Ref<EventAttachment | undefined> = ref(undefined);
-
+const isVisible: Ref<boolean> = ref(false);
+  
 const props = defineProps<MessageProps>();
 
 const { room } = props;
@@ -143,7 +145,7 @@ const _processThread = () => {
 
   items.value = eventItems.map((e: MatrixEvent) => {
     let ea = $matrix.attachmentManager.getEventAttachment(e);
-    if (showMultiview.value) {
+    if (showMultiview.value && isVisible.value) {
       ea.loadThumbnail();
     }
     return ea;
@@ -182,6 +184,14 @@ const layoutedItems = computed(() => {
   }
   return rows;
 });
+
+const onIntersect = (isIntersecting: boolean, entries: any, observer: any) => {
+  isVisible.value = isIntersecting;
+  if (showMultiview.value && isIntersecting) {
+    items.value.forEach((a) => a.loadThumbnail());
+  }
+};
+
 </script>
 <style lang="scss">
 @use "@/assets/css/chat.scss" as *;