Add basic functionality to alter URL

.editorconfig

@@ -3,6 +3,7 @@ root = true
 [*.{js,ts,tsx,mjs}]
 indent_size = 2
 indent_style = space
+max_line_length = 80
 
 [*.scss]
 indent_size = 2
@@ -13,4 +14,4 @@ indent_size = 2
 indent_style = space
 
 [*.md]
-max_line_length = 100
+max_line_length = 100

src/main.test.ts

@@ -15,6 +15,51 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-test("Placeholder", () => {
-  // Placeholder
+
+import { SiteData, amazonComParam, builtinSiteData } from "./site_data";
+import { generateActivatingUrl, generateDisablingUrl } from "./main";
+
+describe("generate Url", () => {
+  const activatingResult = "https://example.com/?result=activated" as const;
+  const disablingResult = "https://example.com/?notactivated" as const;
+  const matchingUrl = "https://example.com";
+  const unmatchingUrl = "https://example.org";
+  const siteData = [
+    {
+      name: "Test Example",
+      urlRegex: /https:\/\/example\.com/,
+      activatingFunc: (): string => activatingResult,
+      disablingFunc: (): string => disablingResult,
+    },
+  ] as const satisfies SiteData;
+
+  test("Returns activating function result if URL matches", () => {
+    expect(generateActivatingUrl(matchingUrl, siteData)).toBe(activatingResult);
+  });
+
+  test("Returns disabling function result if URL matches", () => {
+    expect(generateDisablingUrl(matchingUrl, siteData)).toBe(disablingResult);
+  });
+
+  for (const func of [generateActivatingUrl, generateDisablingUrl] as const) {
+    test("Returns null if no URL matches", () => {
+      expect(func(unmatchingUrl, siteData)).toBeNull();
+    });
+  }
+
+  describe("builtin sitedata", () => {
+    test("Amazon.com activating matched", () => {
+      expect(
+        generateActivatingUrl("https://www.amazon.com/s?", builtinSiteData),
+      ).toBe(
+        `https://www.amazon.com/s?${amazonComParam.key}=${encodeURIComponent(amazonComParam.value)}`,
+      );
+    });
+
+    test("Amazon.com disabling matched", () => {
+      expect(
+        generateDisablingUrl("https://www.amazon.com/s?rh=", builtinSiteData),
+      ).toBe("https://www.amazon.com/s");
+    });
+  });
 });

src/main.ts

@@ -0,0 +1,46 @@
+/** @license GPL-3.0-or-later
+ *
+ * Copyright (C) 2024 8 Hobbies, LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program 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 General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import type { SiteData, SiteDataEntry } from "./site_data";
+
+function getMatchedSite(url: string, siteData: SiteData): SiteDataEntry | null {
+  const matchedSite = siteData.find((siteDataEntry) =>
+    siteDataEntry.urlRegex.exec(url),
+  );
+
+  return matchedSite ?? null;
+}
+
+/** Returns the updated URL of the functionality of this extension on a given current URL. */
+export function generateActivatingUrl(
+  url: string,
+  siteData: SiteData,
+): string | null {
+  const matchedSite = getMatchedSite(url, siteData);
+
+  return matchedSite?.activatingFunc(url) ?? null;
+}
+
+export function generateDisablingUrl(
+  url: string,
+  siteData: SiteData,
+): string | null {
+  const matchedSite = getMatchedSite(url, siteData);
+
+  return matchedSite?.disablingFunc(url) ?? null;
+}

src/manifest.json

@@ -6,7 +6,7 @@
   },
   "minimum_chrome_version": "128",
   "permissions": ["storage"],
-  "host_permissions": ["*://www.amazon.com/*"],
+  "host_permissions": ["https://www.amazon.com/s?*"],
   "action": {},
   "browser_specific_settings": {
     "gecko": {

src/site_data.ts

@@ -0,0 +1,47 @@
+/** @license GPL-3.0-or-later
+ *
+ * Copyright (C) 2024 8 Hobbies, LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program 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 General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { addUrlParam, removeUrlParam } from "./utils";
+
+export interface SiteDataEntry {
+  name: string;
+  // Regular expression to match the website.
+  urlRegex: RegExp;
+  // Function being called when the user visits a website of interest.
+  activatingFunc: (url: string) => string | null;
+  // Function being called when the user clicks on the extension icon to disable.
+  disablingFunc: (url: string) => string | null;
+}
+
+export type SiteData = SiteDataEntry[];
+
+export const amazonComParam = {
+  key: "rh",
+  value: "n:16310101,p_6:ATVPDKIKX0DER",
+};
+
+export const builtinSiteData = [
+  {
+    name: "Amazon.com",
+    urlRegex: /https:\/\/www\.amazon\.com\/s.*/,
+    disablingFunc: (url: string): string | null =>
+      removeUrlParam(url, amazonComParam.key),
+    activatingFunc: (url: string): string | null =>
+      addUrlParam(url, amazonComParam.key, amazonComParam.value),
+  },
+] as const satisfies SiteData;

src/utils.ts

@@ -0,0 +1,55 @@
+/** @license GPL-3.0-or-later
+ *
+ * Copyright (C) 2024 8 Hobbies, LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program 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 General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/** Add a param to a URL. */
+export function addUrlParam(
+  url: string,
+  paramKey: string,
+  paramValue: string,
+): string | null {
+  const parsedUrl = URL.parse(url);
+
+  // TODO: Impossible to create a case to trigger this part for now. Remove the coverage exception once we can.
+  /* c8 ignore start */
+  if (parsedUrl === null) {
+    // Not a URL.
+    console.error(`${url} is not a URL.`);
+    return null;
+  }
+  /* c8 ignore stop */
+
+  parsedUrl.searchParams.set(paramKey, paramValue);
+  return parsedUrl.toString();
+}
+
+/** Remove a param from a URL. */
+export function removeUrlParam(url: string, paramKey: string): string | null {
+  const parsedUrl = URL.parse(url);
+
+  // TODO: Impossible to create a case to trigger this part for now. Remove the coverage exception once we can.
+  /* c8 ignore start */
+  if (parsedUrl === null) {
+    // Not a URL.
+    console.error(`${url} is not a URL.`);
+    return null;
+  }
+  /* c8 ignore stop */
+
+  parsedUrl.searchParams.delete(paramKey);
+  return parsedUrl.toString();
+}