import { __ID__, filePath } from "../consts.mjs";
import { getFile, lastModifiedAt, uploadJson } from "../utils/fs.mjs";
import { promptViaTemplate } from "../utils/dialogs.mjs";

const { HandlebarsApplicationMixin, ApplicationV2 } = foundry.applications.api;
const { randomID } = foundry.utils;

export class ArtistApp extends HandlebarsApplicationMixin(ApplicationV2) {

	// #region Options
	static DEFAULT_OPTIONS = {
		tag: `form`,
		classes: [
			__ID__,
			`ArtistApp`,
		],
		position: {
			width: 350,
		},
		window: {
			contentClasses: [
				`standard-form`,
			],
		},
		form: {
			handler: this.#onSubmit,
			submitOnChange: false,
			closeOnSubmit: true,
		},
		actions: {
			addNewLink: this.#addNewLink,
			deleteLink: this.#deleteLink,
		},
	};

	static PARTS = {
		form: {
			template: filePath(`templates/ArtistApp/form.hbs`),
		},
		linkList: {
			template: filePath(`templates/ArtistApp/linkList.hbs`),
		},
		footer: {
			template: filePath(`templates/ArtistApp/footer.hbs`),
		},
	};
	// #endregion Options

	// #region Instance Data
	/** @type { null | string } */
	#artistID = null;

	/** The artist that is being edited, or the default artist values */
	#artist = { name: ``, links: [] };

	/** @type { null | string } */
	#lastModified = null;

	constructor({ artistID = null, ...opts } = {}) {
		super(opts);
		this.#artistID = artistID;
	};

	get title() {
		if (this.#artistID && this.#artist.name) {
			return game.i18n.format(
				`TB.apps.ArtistApp.title.edit`,
				{ name: this.#artist.name },
			);
		};
		return game.i18n.localize(`TB.apps.ArtistApp.title.create`);
	};
	// #endregion Instance Data

	// #region Lifecycle
	/** Whether or not the database values have been initialized */
	#connected = false;

	/**
	 * This fetches the DB data that we care about for the purposes of being able
	 * to create/edit entries in the Artists DB
	 */
	async #connectToDB() {
		if (this.#connected) { return true };
		this.#lastModified ??= await lastModifiedAt(`storage/db/artists.json`);

		if (this.#artistID) {
			const artists = await getFile(`storage/db/artists.json`);

			if (artists[this.#artistID] == null) {
				ui.notifications.error(_loc(
					`TB.notifs.error.artist-ID-404`,
					{ id: this.#artistID },
				));
				return false;
			};

			Object.assign(this.#artist, artists[this.#artistID]);
		};
		this.#connected = true;
		return true;
	};

	/**
	 * Ensures that the app is in a state where it is allowed to render
	 * before actually letting it render at all.
	 */
	async render(options, ...args) {
		const allowed = await this.#connectToDB();
		if (!allowed) { return this };
		return super.render(options, ...args);
	};

	/**
	 * Makes it so that we update the frame's title to include the Artist name if
	 * we're editing an existing artist instead of creating a new one.
	 */
	_onFirstRender() {
		if (this.#artist.name) {
			this._updateFrame({ window: { title: this.title } });
		};
	};

	/** @this {ArtistApp} */
	static async #onSubmit(event, element, formData) {
		const artist = formData.object;

		if (artist.name.length === 0) { return };
		artist.links = this.#artist.links;
		artist.links.forEach(link => {
			delete link.isNew;
		});

		// Validate the DB hasn't been updated since
		if (this.#artistID) {
			const newLastModified = await lastModifiedAt(`storage/db/artists.json`);
			if (newLastModified !== this.#lastModified) {
				ui.notifications.error(
					`TB.notifs.error.db-out-of-date`,
					{ localize: true },
				);
				return;
			};
		};

		const artists = getFile(`storage/db/artists.json`);

		let id = this.#artistID;
		if (!this.#artistID) {
			do {
				id = randomID();
			} while (artists[id] != null);
		};
		artists[id] = artist;

		await uploadJson(`db`, `artists.json`, artists);
	};
	// #endregion Lifecycle

	// #region Data Prep
	async _prepareContext() {
		const ctx = {
			meta: {
				idp: this.id,
			},
			artist: this.#artist,
		};

		return ctx;
	};
	// #endregion Data Prep

	// #region Actions
	/** @this {ArtistApp} */
	static async #addNewLink() {
		const link = await promptViaTemplate(
			`TB.dialogs.Link.title`,
			`templates/Dialogs/Link.hbs`,
		);
		link.isNew = true;
		this.#artist.links.push(link);
		this.render({ parts: [ `linkList` ] });
	};

	/** @this {ArtistApp} */
	static async #deleteLink(event, element) {
		const index = element.closest(`[data-index]`)?.dataset.index;
		if (index == null) { return };
		this.#artist.links.splice(index, 1);
		this.render({ parts: [ `linkList` ] });
	};
	// #endregion Actions
};