Add ability to switch to tab on click

src/ts/browser-action.ts

@@ -9,5 +9,16 @@ const MAIN_TEMPLATE: twig.Template = twig.twig({href: MAIN_TEMPLATE_URI, async:
 document.addEventListener("DOMContentLoaded", () => {
 	tabs.getWindows((windows: chrome.windows.Window[]) => {
 		document.querySelector("body").innerHTML = String(MAIN_TEMPLATE.render({windows}));
+		registerTabClickListeners();
 	});
 });
+
+function registerTabClickListeners(): void {
+	let tabElements = document.getElementsByClassName("tab");
+	[].forEach.call(tabElements, (element) => {
+		element.addEventListener("click", (event) => {
+			let tabID = parseInt(event.target.getAttribute("tab-id"));
+			tabs.switchTo(tabID);
+		});
+	});
+}

src/ts/tabs.ts

@@ -1,4 +1,4 @@
-export {getWindows};
+export {getWindows, switchTo};
 
 let windowCache: chrome.windows.Window[] = [];
 
@@ -14,3 +14,13 @@ function getWindows(callback: (windows: chrome.windows.Window[]) => void): void
 		callback(windows);
 	});
 }
+
+/**
+ * switchTo makes the tab with the given id active.
+ *
+ * @param {number} tabID The tab to switch to.
+ * @returns {void}
+ */
+function switchTo(tabID: number): void {
+	chrome.tabs.update(tabID, {active: true});
+}