import type Koa from "koa";
import Router from "@koa/router";
import { OAuth2 } from "oauth";
import { v4 as uuid } from "uuid";
import { IsNull } from "typeorm";
import { getJson } from "@/misc/fetch.js";
import config from "@/config/index.js";
import { publishMainStream } from "@/services/stream.js";
import { fetchMeta } from "@/misc/fetch-meta.js";
import { Users, UserProfiles } from "@/models/index.js";
import type { ILocalUser } from "@/models/entities/user.js";
import { redisClient } from "../../../db/redis.js";
import signin from "../common/signin.js";

function getUserToken(ctx: Koa.BaseContext): string | null {
	return ((ctx.headers["cookie"] || "").match(/igi=(\w+)/) || [null, null])[1];
}

function compareOrigin(ctx: Koa.BaseContext): boolean {
	function normalizeUrl(url?: string): string {
		return url ? (url.endsWith("/") ? url.substr(0, url.length - 1) : url) : "";
	}

	const referer = ctx.headers["referer"];

	return normalizeUrl(referer) === normalizeUrl(config.url);
}

// Init router
const router = new Router();

router.get("/disconnect/github", async (ctx) => {
	if (!compareOrigin(ctx)) {
		ctx.throw(400, "invalid origin");
		return;
	}

	const userToken = getUserToken(ctx);
	if (!userToken) {
		ctx.throw(400, "signin required");
		return;
	}

	const user = await Users.findOneByOrFail({
		host: IsNull(),
		token: userToken,
	});

	const profile = await UserProfiles.findOneByOrFail({ userId: user.id });

	profile.integrations.github = undefined;

	await UserProfiles.update(user.id, {
		integrations: profile.integrations,
	});

	ctx.body = "GitHubの連携を解除しました :v:";

	// Publish i updated event
	publishMainStream(
		user.id,
		"meUpdated",
		await Users.pack(user, user, {
			detail: true,
			includeSecrets: true,
		}),
	);
});

async function getOath2() {
	const meta = await fetchMeta(true);

	if (
		meta.enableGithubIntegration &&
		meta.githubClientId &&
		meta.githubClientSecret
	) {
		return new OAuth2(
			meta.githubClientId,
			meta.githubClientSecret,
			"https://github.com/",
			"login/oauth/authorize",
			"login/oauth/access_token",
		);
	} else {
		return null;
	}
}

router.get("/connect/github", async (ctx) => {
	if (!compareOrigin(ctx)) {
		ctx.throw(400, "invalid origin");
		return;
	}

	const userToken = getUserToken(ctx);
	if (!userToken) {
		ctx.throw(400, "signin required");
		return;
	}

	const params = {
		redirect_uri: `${config.url}/api/gh/cb`,
		scope: ["read:user"],
		state: uuid(),
	};

	redisClient.set(userToken, JSON.stringify(params));

	const oauth2 = await getOath2();
	ctx.redirect(oauth2!.getAuthorizeUrl(params));
});

router.get("/signin/github", async (ctx) => {
	const sessid = uuid();

	const params = {
		redirect_uri: `${config.url}/api/gh/cb`,
		scope: ["read:user"],
		state: uuid(),
	};

	ctx.cookies.set("signin_with_github_sid", sessid, {
		path: "/",
		secure: config.url.startsWith("https"),
		httpOnly: true,
	});

	redisClient.set(sessid, JSON.stringify(params));

	const oauth2 = await getOath2();
	ctx.redirect(oauth2!.getAuthorizeUrl(params));
});

router.get("/gh/cb", async (ctx) => {
	const userToken = getUserToken(ctx);

	const oauth2 = await getOath2();

	if (!userToken) {
		const sessid = ctx.cookies.get("signin_with_github_sid");

		if (!sessid) {
			ctx.throw(400, "invalid session");
			return;
		}

		const code = ctx.query.code;

		if (!code || typeof code !== "string") {
			ctx.throw(400, "invalid session");
			return;
		}

		const { redirect_uri, state } = await new Promise<any>((res, rej) => {
			redisClient.get(sessid, async (_, state) => {
				res(JSON.parse(state));
			});
		});

		if (ctx.query.state !== state) {
			ctx.throw(400, "invalid session");
			return;
		}

		const { accessToken } = await new Promise<any>((res, rej) =>
			oauth2!.getOAuthAccessToken(
				code,
				{
					redirect_uri,
				},
				(err, accessToken, refresh, result) => {
					if (err) {
						rej(err);
					} else if (result.error) {
						rej(result.error);
					} else {
						res({ accessToken });
					}
				},
			),
		);

		const { login, id } = (await getJson(
			"https://api.github.com/user",
			"application/vnd.github.v3+json",
			10 * 1000,
			{
				Authorization: `bearer ${accessToken}`,
			},
		)) as Record<string, unknown>;
		if (typeof login !== "string" || typeof id !== "string") {
			ctx.throw(400, "invalid session");
			return;
		}

		const link = await UserProfiles.createQueryBuilder()
			.where("\"integrations\"->'github'->>'id' = :id", { id: id })
			.andWhere('"userHost" IS NULL')
			.getOne();

		if (link == null) {
			ctx.throw(
				404,
				`@${login}と連携しているMisskeyアカウントはありませんでした...`,
			);
			return;
		}

		signin(
			ctx,
			(await Users.findOneBy({ id: link.userId })) as ILocalUser,
			true,
		);
	} else {
		const code = ctx.query.code;

		if (!code || typeof code !== "string") {
			ctx.throw(400, "invalid session");
			return;
		}

		const { redirect_uri, state } = await new Promise<any>((res, rej) => {
			redisClient.get(userToken, async (_, state) => {
				res(JSON.parse(state));
			});
		});

		if (ctx.query.state !== state) {
			ctx.throw(400, "invalid session");
			return;
		}

		const { accessToken } = await new Promise<any>((res, rej) =>
			oauth2!.getOAuthAccessToken(
				code,
				{ redirect_uri },
				(err, accessToken, refresh, result) => {
					if (err) {
						rej(err);
					} else if (result.error) {
						rej(result.error);
					} else {
						res({ accessToken });
					}
				},
			),
		);

		const { login, id } = (await getJson(
			"https://api.github.com/user",
			"application/vnd.github.v3+json",
			10 * 1000,
			{
				Authorization: `bearer ${accessToken}`,
			},
		)) as Record<string, unknown>;

		if (typeof login !== "string" || typeof id !== "string") {
			ctx.throw(400, "invalid session");
			return;
		}

		const user = await Users.findOneByOrFail({
			host: IsNull(),
			token: userToken,
		});

		const profile = await UserProfiles.findOneByOrFail({ userId: user.id });

		await UserProfiles.update(user.id, {
			integrations: {
				...profile.integrations,
				github: {
					accessToken: accessToken,
					id: id,
					login: login,
				},
			},
		});

		ctx.body = `GitHub: @${login} を、Misskey: @${user.username} に接続しました！`;

		// Publish i updated event
		publishMainStream(
			user.id,
			"meUpdated",
			await Users.pack(user, user, {
				detail: true,
				includeSecrets: true,
			}),
		);
	}
});

export default router;