import type { Media, MediaTitle } from "./media";

interface SchedulePage {
	data: {
		Page: {
			media: {
				title: MediaTitle;
				synonyms: string[];
				id: number;
				idMal: number;
				episodes: number;
				nextAiringEpisode?: {
					episode: number;
					airingAt?: number;
				};
				coverImage: {
					extraLarge: string;
					medium: string;
				};
			}[];
			pageInfo: {
				hasNextPage: boolean;
			};
		};
	};
}

const schedulePage = async (
	page: number,
	year: number,
	season: "WINTER" | "SPRING" | "SUMMER" | "FALL",
): Promise<SchedulePage> =>
	await (
		await fetch("https://graphql.anilist.co", {
			method: "POST",
			headers: {
				"Content-Type": "application/json",
				Accept: "application/json",
			},
			body: JSON.stringify({
				query: `{
  Page(page: ${page}) {
    pageInfo {
      hasNextPage
    }
    media(season: ${season}, seasonYear: ${year}) {
      id idMal episodes synonyms
      title { english romaji native }
			nextAiringEpisode { episode airingAt }
      coverImage { extraLarge medium }
    }
  }
}`,
			}),
		})
	).json();

type Season = "WINTER" | "SPRING" | "SUMMER" | "FALL";

export const scheduleMediaListCollection = async (
	year: number,
	season: Season,
	includeLastSeason = false,
) => {
	const scheduledMedia = [];
	let page = 1;
	let currentPage = await schedulePage(page, year, season);

	for (const candidate of currentPage.data.Page.media)
		scheduledMedia.push(candidate);

	while (currentPage["data"]["Page"]["pageInfo"]["hasNextPage"]) {
		for (const candidate of currentPage.data.Page.media)
			scheduledMedia.push(candidate);

		page += 1;
		currentPage = await schedulePage(page, year, season);
	}

	for (const candidate of currentPage.data.Page.media)
		scheduledMedia.push(candidate);

	if (includeLastSeason) {
		const lastSeason = {
			WINTER: "FALL",
			SPRING: "WINTER",
			SUMMER: "SPRING",
			FALL: "SUMMER",
		}[season];

		const lastSeasonYear = season === "WINTER" ? year - 1 : year;

		let page = 1;
		let currentPage = await schedulePage(
			page,
			lastSeasonYear,
			lastSeason as Season,
		);

		for (const candidate of currentPage.data.Page.media)
			scheduledMedia.push(candidate);

		while (currentPage["data"]["Page"]["pageInfo"]["hasNextPage"]) {
			for (const candidate of currentPage.data.Page.media)
				scheduledMedia.push(candidate);

			page += 1;
			currentPage = await schedulePage(
				page,
				lastSeasonYear,
				lastSeason as Season,
			);
		}

		for (const candidate of currentPage.data.Page.media)
			scheduledMedia.push(candidate);
	}

	return scheduledMedia as Partial<Media[]>;
};