From 00eb5363f11499e019803e2e9c03d6a9fcd2edca Mon Sep 17 00:00:00 2001
From: Louis Chemineau <louis@chmn.me>
Date: Thu, 16 Jan 2025 11:42:51 +0100
Subject: [PATCH] feat: Fallback to manually loading media on error

This is needed for E2EE files that will error when loading them directly from the HTML element's src attribute.

Signed-off-by: Louis Chemineau <louis@chmn.me>
---
 src/components/Audios.vue      | 37 +++++++++++++++++++++++++++++++---
 src/components/Images.vue      | 10 +++++++--
 src/components/Videos.vue      | 33 +++++++++++++++++++++++++++---
 src/services/mediaPreloader.ts | 19 +++++++++++++++++
 4 files changed, 91 insertions(+), 8 deletions(-)
 create mode 100644 src/services/mediaPreloader.ts

diff --git a/src/components/Audios.vue b/src/components/Audios.vue
index 5c74fbb72..1c5772de9 100644
--- a/src/components/Audios.vue
+++ b/src/components/Audios.vue
@@ -6,13 +6,14 @@
 <template>
 	<!-- Plyr currently replaces the parent. Wrapping to prevent this
 	https://github.com/redxtech/vue-plyr/issues/259 -->
-	<div v-if="src">
+	<div v-if="url">
 		<VuePlyr ref="plyr"
 			:options="options">
 			<audio ref="audio"
 				:autoplay="active"
-				:src="src"
+				:src="url"
 				preload="metadata"
+				@error.capture.prevent.stop.once="onFail"
 				@ended="donePlaying"
 				@canplay="doneLoading">
 
@@ -28,13 +29,19 @@
 	</div>
 </template>
 
-<script>
+<script lang='ts'>
+import Vue from 'vue'
+import AsyncComputed from 'vue-async-computed'
 // eslint-disable-next-line n/no-missing-import
 import '@skjnldsv/vue-plyr/dist/vue-plyr.css'
+
 import logger from '../services/logger.js'
+import { preloadMedia } from '../services/mediaPreloader'
 
 const VuePlyr = () => import(/* webpackChunkName: 'plyr' */'@skjnldsv/vue-plyr')
 
+Vue.use(AsyncComputed)
+
 export default {
 	name: 'Audios',
 
@@ -42,6 +49,12 @@ export default {
 		VuePlyr,
 	},
 
+	data() {
+		return {
+			fallback: false,
+		}
+	},
+
 	computed: {
 		player() {
 			return this.$refs.plyr.player
@@ -57,6 +70,16 @@ export default {
 		},
 	},
 
+	asyncComputed: {
+		async url(): Promise<string> {
+			if (this.fallback) {
+				return preloadMedia(this.filename)
+			} else {
+				return this.src
+			}
+		},
+	},
+
 	watch: {
 		active(val, old) {
 			// the item was hidden before and is now the current view
@@ -94,6 +117,14 @@ export default {
 			this.$refs.audio.autoplay = false
 			this.$refs.audio.load()
 		},
+
+		// Fallback to the original image if not already done
+		onFail() {
+			if (!this.fallback) {
+				console.error(`Loading of file ${this.filename} failed, falling back to fetching it by hand`)
+				this.fallback = true
+			}
+		},
 	},
 }
 </script>
diff --git a/src/components/Images.vue b/src/components/Images.vue
index e2655d728..a4a5e0f97 100644
--- a/src/components/Images.vue
+++ b/src/components/Images.vue
@@ -72,7 +72,7 @@
 	</div>
 </template>
 
-<script>
+<script lang="ts">
 import Vue from 'vue'
 import AsyncComputed from 'vue-async-computed'
 import PlayCircleOutline from 'vue-material-design-icons/PlayCircleOutline.vue'
@@ -85,6 +85,7 @@ import { NcLoadingIcon } from '@nextcloud/vue'
 import ImageEditor from './ImageEditor.vue'
 import { findLivePhotoPeerFromFileId } from '../utils/livePhotoUtils'
 import { getDavPath } from '../utils/fileUtils'
+import { preloadMedia } from '../services/mediaPreloader'
 
 Vue.use(AsyncComputed)
 
@@ -181,7 +182,12 @@ export default {
 			// If there is no preview and we have a direct source
 			// load it instead
 			if (this.source && !this.hasPreview && !this.previewUrl) {
-				return this.source
+				// If loading the source failed once, let's try fetching it by had
+				if (this.fallback) {
+					return preloadMedia(this.filename)
+				} else {
+					return this.source
+				}
 			}
 
 			// If loading the preview failed once, let's load the original file
diff --git a/src/components/Videos.vue b/src/components/Videos.vue
index 576002883..83d90d538 100644
--- a/src/components/Videos.vue
+++ b/src/components/Videos.vue
@@ -6,7 +6,7 @@
 <template>
 	<!-- Plyr currently replaces the parent. Wrapping to prevent this
 	https://github.com/redxtech/vue-plyr/issues/259 -->
-	<div v-if="src">
+	<div v-if="url">
 		<VuePlyr ref="plyr"
 			:options="options"
 			:style="{
@@ -17,8 +17,9 @@
 				:autoplay="active ? true : null"
 				:playsinline="true"
 				:poster="livePhotoPath"
-				:src="src"
+				:src="url"
 				preload="metadata"
+				@error.capture.prevent.stop.once="onFail"
 				@ended="donePlaying"
 				@canplay="doneLoading"
 				@loadedmetadata="onLoadedMetadata">
@@ -35,18 +36,25 @@
 	</div>
 </template>
 
-<script>
+<script lang='ts'>
 // eslint-disable-next-line n/no-missing-import
+import Vue from 'vue'
+import AsyncComputed from 'vue-async-computed'
 import '@skjnldsv/vue-plyr/dist/vue-plyr.css'
+
 import { imagePath } from '@nextcloud/router'
+
 import logger from '../services/logger.js'
 import { findLivePhotoPeerFromName } from '../utils/livePhotoUtils'
 import { getPreviewIfAny } from '../utils/previewUtils'
+import { preloadMedia } from '../services/mediaPreloader.js'
 
 const VuePlyr = () => import(/* webpackChunkName: 'plyr' */'@skjnldsv/vue-plyr')
 
 const blankVideo = imagePath('viewer', 'blank.mp4')
 
+Vue.use(AsyncComputed)
+
 export default {
 	name: 'Videos',
 
@@ -56,6 +64,7 @@ export default {
 	data() {
 		return {
 			isFullscreenButtonVisible: false,
+			fallback: false,
 		}
 	},
 
@@ -86,6 +95,16 @@ export default {
 		},
 	},
 
+	asyncComputed: {
+		async url(): Promise<string> {
+			if (this.fallback) {
+				return preloadMedia(this.filename)
+			} else {
+				return this.src
+			}
+		},
+	},
+
 	watch: {
 		active(val, old) {
 			// the item was hidden before and is now the current view
@@ -155,6 +174,14 @@ export default {
 				this.player.stop()
 			}
 		},
+
+		// Fallback to the original image if not already done
+		onFail() {
+			if (!this.fallback) {
+				console.error(`Loading of file ${this.filename} failed, falling back to fetching it by hand`)
+				this.fallback = true
+			}
+		},
 	},
 }
 </script>
diff --git a/src/services/mediaPreloader.ts b/src/services/mediaPreloader.ts
new file mode 100644
index 000000000..0a6a89477
--- /dev/null
+++ b/src/services/mediaPreloader.ts
@@ -0,0 +1,19 @@
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+/* eslint-disable jsdoc/require-jsdoc */
+
+import type { ResponseDataDetailed, WebDAVClient } from 'webdav'
+
+import { getClient, getRootPath } from '@nextcloud/files/dav'
+
+// Manually load a WebDAV media from its filename, then expose the received Blob as an object URL.
+// This is needed for E2EE files that will error when loading them directly from the HTML element's src attribute.
+// Can be removed if we ever move the E2EE proxy to a service worker.
+export async function preloadMedia(filename: string): Promise<string> {
+	const client = getClient() as WebDAVClient
+	const response = await client.getFileContents(`${getRootPath}${filename}`, { details: true }) as ResponseDataDetailed<ArrayBuffer>
+	return URL.createObjectURL(new Blob([response.data], { type: response.headers['content-type'] }))
+}