const IS_FIREFOX = (typeof chrome === "undefined");
const IS_CHROME = (typeof browser === "undefined");

class DomManager {
	constructor() {
		this.elements = {
			lastActivityItemDate: document.getElementById("last-activity-item-date"),
			status: document.getElementById("status"),
			netflixManagerStatus: document.getElementById("netflixmanager-status"),
			mainManagerStatus: document.getElementById("mainmanager-status"),
			backend: document.getElementById("backend"),
			buildIdentifier: document.getElementById("build-identifier"),
			authUrl: document.getElementById("auth-url"),
			lastActivityItemTitle: document.getElementById("last-activity-item-title"),
			pagesGot: document.getElementById("pages-got"),
			itemsGot: document.getElementById("items-got"),
			firstItemTitle: document.getElementById("first-item-title"),
			firstItemDate: document.getElementById("first-item-date"),
			lastItemTitle: document.getElementById("last-item-title"),
			lastItemDate: document.getElementById("last-item-date"),
			button: document.getElementById("button"),
		};
		this.buttonClickHandlers = [];

		this.elements.button.onclick = () => {
			this._handleButtonClick();
		};
	}

	setLastActivityDate(date) {
		this.elements.lastActivityItemDate.innerText = date;
	}

	setLastActivityTitle(title) {
		this.elements.lastActivityItemTitle.innerText = title;
	}

	setStatus(status) {
		this.elements.status.innerText = status;
		if (status === "Ready") this.elements.button.disabled = false;
		else this.elements.button.disabled = true;
	}

	setNetflixManagerStatus(status) {
		this.elements.netflixManagerStatus.innerText = status;
	}

	setMainManagerStatus(status) {
		this.elements.mainManagerStatus.innerText = status;
	}

	setAuthUrl(authUrl) {
		this.elements.authUrl.innerText = authUrl;
	}

	setBuildIdentifier(buildIdentifier) {
		this.elements.buildIdentifier.innerText = buildIdentifier;
	}

	setBackend(backend) {
		this.elements.backend.innerText = backend;
	}

	setPagesGot(pagesGot) {
		this.elements.pagesGot.innerText = pagesGot;
	} 
	setItemsGot(itemsGot) {
		this.elements.itemsGot.innerText = itemsGot;
	} 
	setFirstItemTitle(firstItemTitle) {
		this.elements.firstItemTitle.innerText = firstItemTitle;
	} 
	setFirstItemDate(firstItemDate) {
		this.elements.firstItemDate.innerText = firstItemDate;
	} 
	setLastItemTitle(lastItemTitle) {
		this.elements.lastItemTitle.innerText = lastItemTitle;
	} 
	setLastItemDate(lastItemDate) {
		this.elements.lastItemDate.innerText = lastItemDate;
	} 

	onButtonClick(cb) {
		this.buttonClickHandlers.push(cb);
	}

	_handleButtonClick() {
		this.buttonClickHandlers.forEach(cb => {
			cb();
		});
	}
}

class NetflixManager {
	constructor() {
		this.page = 0;
		domManager.setNetflixManagerStatus("Waiting for authUrl and buildIdentifier");
		this.fetchAuthUrl();
		this.fetchBuildIdentifier();
		this.gotAuthUrlFromBackground = false;
		this.gotBuildIdentifierFromBackground = false;
	}

	async fetchAuthUrl() {
		if (IS_FIREFOX) this.authUrl = await browser.runtime.sendMessage({ type: `getAuthUrl` });
		if (IS_CHROME) this.authUrl = await new Promise(resolve => {
			chrome.runtime.sendMessage({ type: `getAuthUrl` }, response => {
				resolve(response);
			})
		});
		domManager.setAuthUrl(this.authUrl);
		this.gotAuthUrlFromBackground = true;
		if (this.gotBuildIdentifierFromBackground && this.gotAuthUrlFromBackground && !this.buildIdentifier && !this.authUrl)
			domManager.setNetflixManagerStatus("Background does not have auth url and build identifier yet. Please reload the Netflix page on the correct profile.");
	}

	async fetchBuildIdentifier() {
		if (IS_FIREFOX) this.buildIdentifier = await browser.runtime.sendMessage({ type: `getBuildIdentifier` });
		if (IS_CHROME) this.buildIdentifier = await new Promise(resolve => {
			chrome.runtime.sendMessage({ type: `getBuildIdentifier` }, response => {
				resolve(response);
			});
		});
		domManager.setBuildIdentifier(this.buildIdentifier);
		this.gotBuildIdentifierFromBackground = true;
		if (this.gotBuildIdentifierFromBackground && this.gotAuthUrlFromBackground && !this.buildIdentifier && !this.authUrl)
			domManager.setNetflixManagerStatus("Background does not have auth url and build identifier yet. Please reload the Netflix page on the correct profile.");
	}

	isReady() {
		return new Promise(resolve => {
			let intervalId = setInterval(() => {
				if (this.authUrl && this.buildIdentifier) {
					clearInterval(intervalId);
					domManager.setNetflixManagerStatus("Ready");
					resolve();
				} else console.log("Auth URL or build identifier not set yet in NetflixManager");
			}, 250);
		});
	}

	getURL() {
		return `https://www.netflix.com/api/shakti/${this.buildIdentifier}/viewingactivity?language=en-US&authURL=${this.authUrl}&pg=${this.page}`;
	}

	getPage() {
		console.log(`Getting page ${this.page}`);
		domManager.setNetflixManagerStatus(`Getting page ${this.page}`);
		return new Promise(resolve => {
			setTimeout(() => {
				const URL = this.getURL();
				fetch(new Request(URL))
					.then(response => {
						if (response.status === 200) {
							return response.json();
						} else {
							throw new Error("Something went wrong with the API.");
						}
					})
					.then(response => {
						resolve(response);
					})
					.catch(error => {
						console.error(error);
					});
			}, Math.floor(Math.random() * 750) + 250);
		});
	}
}

class MainManager {
	constructor() {
		this.items = [];
		domManager.setMainManagerStatus("Fetching last activity item");
		this.fetchLastActivityItem();
	}

	async fetchLastActivityItem() {
		socket.emit("getLastActivityItem", lastActivityItem => {
			this.lastActivityItem = lastActivityItem;
			let date = (new Date(this.lastActivityItem.date)).toLocaleString();
			let title = this.lastActivityItem.seriesTitle ? `${this.lastActivityItem.seriesTitle} - ${this.lastActivityItem.episodeTitle}` : `${this.lastActivityItem.title}`;
			domManager.setLastActivityDate(date);
			domManager.setLastActivityTitle(title);
		});
	}

	isReady() {
		return new Promise(resolve => {
			let intervalId = setInterval(() => {
				if (this.lastActivityItem) {
					clearInterval(intervalId);
					domManager.setMainManagerStatus("Ready");
					resolve();
				}
			}, 250);
		});
	}

	getMore() {
		return new Promise(async resolve => {
			let activityPage = await netflixManager.getPage();
			domManager.setPagesGot(netflixManager.page + 1);
			netflixManager.page++;
			let resolved = false;

			activityPage.viewedItems.forEach(activityItem => {
				if (activityItem.date > this.lastActivityItem.date) {
					this.items.push(activityItem);
				} else {
					resolved = true;
				}
			});

			domManager.setItemsGot(this.items.length);
			const firstItem = (this.items.length > 0) ? this.items[this.items.length - 1] : null;
			const lastItem = (this.items.length > 0) ? this.items[0] : null;

			if (firstItem) {
				let firstItemDate = (new Date(firstItem.date)).toLocaleString();
				let firstItemTitle = firstItem.seriesTitle ? `${firstItem.seriesTitle} - ${firstItem.episodeTitle}` : `${firstItem.title}`;
				domManager.setFirstItemDate(firstItemDate);
				domManager.setFirstItemTitle(firstItemTitle);
			} else {
				domManager.setFirstItemDate("No item");
				domManager.setFirstItemTitle("No item");
			}

			if (lastItem) {
				let lastItemDate = (new Date(lastItem.date)).toLocaleString();
				let lastItemTitle = lastItem.seriesTitle ? `${lastItem.seriesTitle} - ${lastItem.episodeTitle}` : `${lastItem.title}`;
				domManager.setLastItemDate(lastItemDate);
				domManager.setLastItemTitle(lastItemTitle);
			} else {
				domManager.setLastItemDate("No item");
				domManager.setLastItemTitle("No item");
			}

			if (activityPage.viewedItems.length === 0) resolved = true;

			if (resolved) return resolve();
			else this.getMore().then(() => {
				resolve();
			});
		});
	}
}

let domManager;
let netflixManager;
let mainManager;

let socket;

let init = async () => {
	let backend;
	if (IS_FIREFOX) backend = (await browser.storage.local.get("backend")).backend;
	if (IS_CHROME) backend = await new Promise((resolve, reject) => {
		chrome.storage.local.get("backend", response => {
			resolve(response.backend);
		});
	});
	socket = io(backend);
	domManager = new DomManager();
	domManager.setBackend(backend);
	domManager.setStatus("Initializing NetflixManager");
	netflixManager = new NetflixManager();
	domManager.setStatus("Waiting for NetflixManager");
	await netflixManager.isReady();
	domManager.setStatus("Initializing MainManager");
	mainManager = new MainManager();
	domManager.setStatus("Waiting for MainManager");
	await mainManager.isReady();
	domManager.setStatus("Ready");

	domManager.onButtonClick(async () => {
		console.log("On button click, gonna get the items");
		domManager.setStatus("Starting to get items");

		await mainManager.getMore();
		domManager.setNetflixManagerStatus(`Ready`);

		domManager.setStatus("Sending items to backend");
		console.log("Should be done now!");
		console.log(mainManager.items);
		socket.emit("importNewItems", mainManager.items);
		domManager.setStatus("Sent items to backend");
	});
}

init();