Convert some utils to typescript

src/content-repo.ts

@@ -0,0 +1,82 @@
+/*
+Copyright 2015 - 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+/**
+ * @module content-repo
+ */
+
+import * as utils from "./utils";
+
+/**
+ * Get the HTTP URL for an MXC URI.
+ * @param {string} baseUrl The base homeserver url which has a content repo.
+ * @param {string} mxc The mxc:// URI.
+ * @param {Number} width The desired width of the thumbnail.
+ * @param {Number} height The desired height of the thumbnail.
+ * @param {string} resizeMethod The thumbnail resize method to use, either
+ * "crop" or "scale".
+ * @param {Boolean} allowDirectLinks If true, return any non-mxc URLs
+ * directly. Fetching such URLs will leak information about the user to
+ * anyone they share a room with. If false, will return the emptry string
+ * for such URLs.
+ * @return {string} The complete URL to the content.
+ */
+export function getHttpUriForMxc(
+    baseUrl: string,
+    mxc: string,
+    width: number,
+    height: number,
+    resizeMethod: string,
+    allowDirectLinks: boolean,
+): string {
+    if (typeof mxc !== "string" || !mxc) {
+        return '';
+    }
+    if (mxc.indexOf("mxc://") !== 0) {
+        if (allowDirectLinks) {
+            return mxc;
+        } else {
+            return '';
+        }
+    }
+    let serverAndMediaId = mxc.slice(6); // strips mxc://
+    let prefix = "/_matrix/media/r0/download/";
+    const params = {};
+
+    if (width) {
+        params["width"] = Math.round(width);
+    }
+    if (height) {
+        params["height"] = Math.round(height);
+    }
+    if (resizeMethod) {
+        params["method"] = resizeMethod;
+    }
+    if (Object.keys(params).length > 0) {
+        // these are thumbnailing params so they probably want the
+        // thumbnailing API...
+        prefix = "/_matrix/media/r0/thumbnail/";
+    }
+
+    const fragmentOffset = serverAndMediaId.indexOf("#");
+    let fragment = "";
+    if (fragmentOffset >= 0) {
+        fragment = serverAndMediaId.substr(fragmentOffset);
+        serverAndMediaId = serverAndMediaId.substr(0, fragmentOffset);
+    }
+
+    const urlParams = (Object.keys(params).length === 0 ? "" : ("?" + utils.encodeParams(params)));
+    return baseUrl + prefix + serverAndMediaId + urlParams + fragment;
+}