Bunch of updates in preparation for publish

build/camera.js

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2023 Google LLC
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+import initModule from '../build/libapi.mjs';
+// A helper that allows to distinguish critical errors from library errors.
+export function rethrowIfCritical(err) {
+    // If it's precisely Error, it's a custom error; anything else - SyntaxError,
+    // WebAssembly.RuntimeError, TypeError, etc. - is treated as critical here.
+    if (err?.constructor !== Error) {
+        throw err;
+    }
+}
+const INTERFACE_CLASS = 6; // PTP
+const INTERFACE_SUBCLASS = 1; // MTP
+let ModulePromise;
+export class Camera {
+    #queue = Promise.resolve();
+    #context = null;
+    static async showPicker() {
+        // @ts-ignore
+        await navigator.usb.requestDevice({
+            filters: [
+                {
+                    classCode: INTERFACE_CLASS,
+                    subclassCode: INTERFACE_SUBCLASS
+                }
+            ]
+        });
+    }
+    async connect() {
+        if (!ModulePromise) {
+            ModulePromise = initModule();
+        }
+        let Module = await ModulePromise;
+        this.#context = await new Module.Context();
+    }
+    async #schedule(op) {
+        let res = this.#queue.then(() => op(this.#context));
+        this.#queue = res.catch(rethrowIfCritical);
+        return res;
+    }
+    async disconnect() {
+        if (this.#context && !this.#context.isDeleted()) {
+            this.#context.delete();
+        }
+    }
+    async getConfig() {
+        return this.#schedule(context => context.configToJS());
+    }
+    async getSupportedOps() {
+        if (this.#context) {
+            return await this.#context.supportedOps();
+        }
+        throw new Error('You need to connect to the camera first');
+    }
+    async setConfigValue(name, value) {
+        let uiTimeout;
+        await this.#schedule(context => {
+            // This is terrible, yes... but some configs return too quickly before they're actually updated.
+            // We want to wait some time before updating the UI in that case, but not block subsequent ops.
+            uiTimeout = new Promise(resolve => setTimeout(resolve, 800));
+            return context.setConfigValue(name, value);
+        });
+        await uiTimeout;
+    }
+    async capturePreviewAsBlob() {
+        return this.#schedule(context => context.capturePreviewAsBlob());
+    }
+    async captureImageAsFile() {
+        return this.#schedule(context => context.captureImageAsFile());
+    }
+    async consumeEvents() {
+        return this.#schedule(context => context.consumeEvents());
+    }
+}