const TAB_TITLE_TARGET = "code-server";
// Allow the content-script running in the code-server context to set session storage entries
const CHROMIUM_ACCESS_LEVEL_ENUM = "TRUSTED_AND_UNTRUSTED_CONTEXTS";

const STATUS = Object.freeze({
	UPDATE    : "update",
	SUCCESS   : "success",
	NO_TARGET : "no-target"
});

const CLASSNAME = Object.freeze({
	ACTIVE : "active"
});

const SELECTOR = Object.freeze({
	TRY_AGAIN    : "a[href='#']",
	OPEN_EDITOR  : "button.success",
	MAIN_ELEMENT : "main",
	CARD_ELEMENT : "article",
});

class Popup {
	constructor() {
		// Set session storage access to content-scripts
		chrome.storage.session.setAccessLevel({ accessLevel: CHROMIUM_ACCESS_LEVEL_ENUM });

		this.#bindTryAgain();
		this.#bindOpenEditor();

		this.update();
	}

	/**
	 * Set the current status
	 * 
	 * @param {STATUS} status
	 */
	set #status(status) {
		const mainElement = document.querySelector(SELECTOR.MAIN_ELEMENT);
		// Unset current status
		Object.values(STATUS).forEach(classname => mainElement.classList.remove(classname));

		mainElement.classList.add(status);
	}

	/**
	 * Query active tabs for a code-server tab
	 * 
	 * @returns {STATUS}
	 */
	async update() {
		this.#status = STATUS.UPDATE;

		const tab = await this.#activeTab();
		console.log(tab);

		if (!tab) {
			return this.#status = STATUS.NO_TARGET;
		}

		document.querySelector(SELECTOR.OPEN_EDITOR).querySelector("span").innerText = tab.title.split(" ", 1)[0];
		return this.#status = STATUS.SUCCESS;
	}

	/**
	 * Opens the current code-server tab in the editor and closes this popup
	 * 
	 * @returns {Promise<InjectionResult>|false}
	 */
	async openActiveTab() {
		const tab = await this.#activeTab();

		if (!tab) {
			return false;
		}

		// Inject content script on the target page
		chrome.scripting.executeScript({
			files  : ["assets/js/script.js"],
			target : { tabId: tab.id }
		});

		window.close();
	}

	/**
	 * Query active tabs for a code-server tab
	 * 
	 * @returns {Promise<object|null>}
	 */
	async #activeTab() {
		return await new Promise((resolve) => {
			chrome.tabs.query({ active: true, currentWindow: true }, (tabs) => {
				let activeTab = null;

				tabs.forEach(tab => {
					// Use the last part of the tab title to determine if this tab is a code-server instance
					if (tab.title.slice(TAB_TITLE_TARGET.length * -1) === TAB_TITLE_TARGET) {
						activeTab = tab;
					}
				});

				return resolve(activeTab);
			});
		});
	}

	/**
	 * Bind try again button
	 */
	#bindTryAgain() {
		document.querySelector(SELECTOR.TRY_AGAIN).addEventListener("click", (event) => {
			event.preventDefault();
			this.update();
		});
	}

	/**
	 * Bind open editor button
	 */
	#bindOpenEditor() {
		document.querySelector(SELECTOR.OPEN_EDITOR).addEventListener("click", () => this.openActiveTab());
	}
}

globalThis._Popup = new Popup();