From 9c1bf99d5cf61e2d4796190ad9142aa682d59625 Mon Sep 17 00:00:00 2001
From: Abe Jellinek <jellinek@berkeley.edu>
Date: Fri, 15 Sep 2023 12:03:26 -0400
Subject: [PATCH] Load EPUBs/snapshots from URL

---
 src/dom/common/dom-view.tsx       |  4 ++--
 src/dom/epub/epub-view.ts         |  7 ++++++-
 src/dom/snapshot/snapshot-view.ts | 22 ++++++++++++++--------
 3 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/src/dom/common/dom-view.tsx b/src/dom/common/dom-view.tsx
index e16b16d1..a9a44a0c 100644
--- a/src/dom/common/dom-view.tsx
+++ b/src/dom/common/dom-view.tsx
@@ -113,11 +113,11 @@ abstract class DOMView<State extends DOMViewState, Data> {
 		// support the csp attribute (currently all browsers besides Chrome derivatives)
 		this._iframe.setAttribute('csp', this._getCSP());
 		this.initializedPromise = this._initialize();
-		this._iframe.srcdoc = this._getSrcDoc();
 		options.container.append(this._iframe);
 	}
 
 	protected async _initialize(): Promise<void> {
+		this._iframe.srcdoc = await this._getSrcDoc();
 		return new Promise<void>((resolve, reject) => {
 			this._iframe.addEventListener('load', () => {
 				this._handleIFrameLoad().then(resolve, reject);
@@ -153,7 +153,7 @@ abstract class DOMView<State extends DOMViewState, Data> {
 			+ `script-src ${scriptSrc}; child-src ${childSrc}; form-action ${formAction}`;
 	}
 
-	protected abstract _getSrcDoc(): string;
+	protected abstract _getSrcDoc(): MaybePromise<string>;
 
 	abstract getData(): Data;
 
diff --git a/src/dom/epub/epub-view.ts b/src/dom/epub/epub-view.ts
index 2ef9f24c..f2ab120b 100644
--- a/src/dom/epub/epub-view.ts
+++ b/src/dom/epub/epub-view.ts
@@ -91,11 +91,16 @@ class EPUBView extends DOMView<EPUBViewState, EPUBViewData> {
 			this.book = Epub(options.data.buf.buffer);
 			delete this._options.data.buf;
 		}
+		else if (options.data.baseURI) {
+			this.book = Epub(options.data.baseURI, {
+				openAs: 'epub'
+			});
+		}
 		else if (options.data.book) {
 			this.book = options.data.book;
 		}
 		else {
-			throw new Error('buf or book is required');
+			throw new Error('buf, baseURI, or book is required');
 		}
 	}
 
diff --git a/src/dom/snapshot/snapshot-view.ts b/src/dom/snapshot/snapshot-view.ts
index 36190645..7d8d9c7c 100644
--- a/src/dom/snapshot/snapshot-view.ts
+++ b/src/dom/snapshot/snapshot-view.ts
@@ -43,10 +43,19 @@ class SnapshotView extends DOMView<SnapshotViewState, SnapshotViewData> {
 
 	private _scale!: number;
 
-	protected _getSrcDoc() {
-		let enc = new TextDecoder('utf-8');
-		if (this._options.data.buf) {
-			let text = enc.decode(this._options.data.buf);
+	protected async _getSrcDoc() {
+		if (this._options.data.srcDoc) {
+			return this._options.data.srcDoc;
+		}
+		else if (this._options.data.buf || this._options.data.baseURI !== undefined) {
+			let buf;
+			if (this._options.data.buf) {
+				buf = this._options.data.buf;
+			}
+			else {
+				buf = await fetch(this._options.data.baseURI!).then(r => r.arrayBuffer());
+			}
+			let text = new TextDecoder('utf-8').decode(buf);
 			delete this._options.data.buf;
 			let doc = new DOMParser().parseFromString(text, 'text/html');
 
@@ -69,11 +78,8 @@ class SnapshotView extends DOMView<SnapshotViewState, SnapshotViewData> {
 
 			return new XMLSerializer().serializeToString(doc);
 		}
-		else if (this._options.data.srcDoc) {
-			return this._options.data.srcDoc;
-		}
 		else {
-			throw new Error('buf or srcDoc is required');
+			throw new Error('buf, baseURI, or srcDoc is required');
 		}
 	}