Fix thumbnail view updating

Issue #662

src/components/file_mode/ThumbnailView.vue

@@ -26,9 +26,9 @@
 import utils from "../../plugins/utils";
 import { computed, inject, onBeforeUnmount, onMounted, Ref, ref, useTemplateRef, watch } from "vue";
 import { EventAttachment } from "../../models/eventAttachment";
-import ImageWithProgress from "../ImageWithProgress";
 import { useThumbnail } from "../messages/composition/useThumbnail";
 import { Attachment } from "../../models/attachment";
+import ImageWithProgress from "../ImageWithProgress.vue";
 
 const $$sanitize: any = inject("globalSanitize");
 
@@ -50,8 +50,33 @@ const emits = defineEmits<ThumbnailEmits>();
 
 let { isVideo, isImage, fileTypeIcon, fileTypeIconClass, fileName, fileSize } = useThumbnail(file?.file ?? item?.event);
 const fileURL: Ref<string | undefined> = ref(undefined);
+const source: Ref<string | undefined> = ref(undefined);
 const poster: Ref<string | undefined> = ref(undefined);
 
+const updateSource = () => {
+  if (props.item) {
+    if (isVideo.value || props.item.src) {
+      source.value = props.item.src;
+    } else if (previewOnly) {
+      props.item.loadThumbnail().then((url) => { 
+        source.value = url.data;
+      })
+    } else if (isImage.value) {
+      props.item.loadSrc().then((url) => { 
+        source.value = url.data;
+      })
+    }
+  } else if (props.file) {
+    if (fileURL.value) {
+      URL.revokeObjectURL(fileURL.value);
+    }
+    fileURL.value = URL.createObjectURL(props.file.file);
+    source.value = fileURL.value;
+  } else {
+    source.value = undefined;
+  }
+};
+
 const updatePoster = () => {
   if (props.item && isVideo.value) {
     if (props.item.thumbnail) {
@@ -69,8 +94,10 @@ const updatePoster = () => {
   }
 };
 
+updateSource();
 updatePoster();
 
+
 watch(props, (props: ThumbnailProps) => {
   const updates = useThumbnail(props.file?.file ?? props.item?.event);
   isVideo.value = updates.isVideo.value;
@@ -79,24 +106,10 @@ watch(props, (props: ThumbnailProps) => {
   fileTypeIconClass = updates.fileTypeIconClass;
   fileName = updates.fileName;
   fileSize = updates.fileSize;
+  updateSource();
   updatePoster();
 });
 
-const source = computed(() => {
-  if (item) {
-    if (isVideo.value) {
-      return item.src;
-    }
-    return item.src ? item.src : item.thumbnail;
-  } else if (file) {
-    if (!fileURL.value) {
-      fileURL.value = URL.createObjectURL(file.file);
-    }
-    return fileURL.value;
-  }
-  return undefined;
-});
-
 const loadingProgress = computed(() => {
   if (item) {
     return previewOnly ? item.thumbnailProgress : item.srcProgress;