import { readFile } from "node:fs/promises";
import { db } from "@/db";
import {
	videoUploadJobs,
	videoUploads,
	type TiktokSettings,
	type YoutubeSettings,
} from "@/db/schema";
import { and, desc, eq } from "drizzle-orm";

const VIDEO_TYPES = new Set(["video/mp4", "video/quicktime", "video/webm"]);

export type LatestVideo = {
	id: string;
	title: string;
	thumbnailUrl: string;
	url: string;
	createdAt: number;
	platform: "youtube" | "tiktok";
};

export function validateVideoFile(file: File) {
	if (!VIDEO_TYPES.has(file.type))
		throw new Error("Use an MP4, MOV, or WebM video.");
	if (file.size <= 0) throw new Error("Video cannot be empty.");
}

export function validateThumbnailFile(file: File) {
	if (!file.type.startsWith("image/"))
		throw new Error("Thumbnail must be an image.");
	if (file.size <= 0 || file.size > 10 * 1024 * 1024)
		throw new Error("Thumbnail must be smaller than 10 MB.");
}

export async function getLatestYoutubeVideos(): Promise<LatestVideo[]> {
	const apiKey = process.env.YOUTUBE_API_KEY;
	const channelId = process.env.YOUTUBE_CHANNEL_ID;
	if (!apiKey || !channelId) return [];
	const channels = await fetch(
		`https://www.googleapis.com/youtube/v3/channels?part=contentDetails&id=${encodeURIComponent(channelId)}&key=${encodeURIComponent(apiKey)}`,
		{ cache: "no-store" },
	);
	if (!channels.ok) throw new Error("YouTube channel lookup failed.");
	const channelData = (await channels.json()) as {
		items?: Array<{
			contentDetails?: { relatedPlaylists?: { uploads?: string } };
		}>;
	};
	const playlistId =
		channelData.items?.[0]?.contentDetails?.relatedPlaylists?.uploads;
	if (!playlistId) return [];
	const response = await fetch(
		`https://www.googleapis.com/youtube/v3/playlistItems?part=snippet,contentDetails&playlistId=${encodeURIComponent(playlistId)}&maxResults=10&key=${encodeURIComponent(apiKey)}`,
		{ cache: "no-store" },
	);
	if (!response.ok) throw new Error("YouTube video list failed.");
	const data = (await response.json()) as {
		items?: Array<{
			contentDetails?: { videoId?: string };
			snippet?: {
				title?: string;
				publishedAt?: string;
				thumbnails?: Record<string, { url: string }>;
			};
		}>;
	};
	return (data.items ?? []).flatMap((item) => {
		const id = item.contentDetails?.videoId;
		if (!id) return [];
		return [
			{
				id,
				title: item.snippet?.title ?? "Untitled",
				thumbnailUrl:
					item.snippet?.thumbnails?.high?.url ??
					item.snippet?.thumbnails?.default?.url ??
					"",
				url: `https://www.youtube.com/watch?v=${id}`,
				createdAt: Date.parse(item.snippet?.publishedAt ?? "") || 0,
				platform: "youtube" as const,
			},
		];
	});
}

async function getTiktokAccessToken() {
	const refreshToken = process.env.TIKTOK_REFRESH_TOKEN;
	const clientKey = process.env.TIKTOK_CLIENT_KEY;
	const clientSecret = process.env.TIKTOK_CLIENT_SECRET;
	if (!refreshToken || !clientKey || !clientSecret)
		return process.env.TIKTOK_ACCESS_TOKEN ?? null;
	const response = await fetch("https://open.tiktokapis.com/v2/oauth/token/", {
		method: "POST",
		headers: { "Content-Type": "application/x-www-form-urlencoded" },
		body: new URLSearchParams({
			client_key: clientKey,
			client_secret: clientSecret,
			grant_type: "refresh_token",
			refresh_token: refreshToken,
		}),
	});
	if (!response.ok) throw new Error("TikTok token refresh failed.");
	const data = (await response.json()) as {
		access_token?: string;
		refresh_token?: string;
	};
	return data.access_token ?? null;
}

export async function getLatestTiktokVideos(): Promise<LatestVideo[]> {
	const token = await getTiktokAccessToken();
	if (!token) return [];
	const response = await fetch(
		"https://open.tiktokapis.com/v2/video/list/?fields=id,title,cover_image_url,share_url,create_time",
		{
			method: "POST",
			headers: {
				Authorization: `Bearer ${token}`,
				"Content-Type": "application/json",
			},
			body: JSON.stringify({ max_count: 10 }),
			cache: "no-store",
		},
	);
	if (!response.ok) throw new Error("TikTok video list failed.");
	const data = (await response.json()) as {
		data?: {
			videos?: Array<{
				id: string;
				title?: string;
				cover_image_url?: string;
				share_url?: string;
				create_time?: number;
			}>;
		};
	};
	return (data.data?.videos ?? []).map((video) => ({
		id: video.id,
		title: video.title ?? "Untitled",
		thumbnailUrl: video.cover_image_url ?? "",
		url: video.share_url ?? `https://www.tiktok.com/`,
		createdAt: video.create_time ?? 0,
		platform: "tiktok" as const,
	}));
}

async function youtubeAccessToken() {
	const refreshToken = process.env.YOUTUBE_REFRESH_TOKEN;
	const clientId = process.env.YOUTUBE_CLIENT_ID;
	const clientSecret = process.env.YOUTUBE_CLIENT_SECRET;
	if (!refreshToken || !clientId || !clientSecret)
		throw new Error("YouTube OAuth is not configured.");
	const response = await fetch("https://oauth2.googleapis.com/token", {
		method: "POST",
		headers: { "Content-Type": "application/x-www-form-urlencoded" },
		body: new URLSearchParams({
			client_id: clientId,
			client_secret: clientSecret,
			refresh_token: refreshToken,
			grant_type: "refresh_token",
		}),
	});
	if (!response.ok) throw new Error("YouTube token refresh failed.");
	const data = (await response.json()) as { access_token?: string };
	if (!data.access_token)
		throw new Error("YouTube did not return an access token.");
	return data.access_token;
}

async function publishYoutube(upload: typeof videoUploads.$inferSelect) {
	const token = await youtubeAccessToken();
	const settings = upload.youtubeSettings as YoutubeSettings;
	const body = {
		snippet: {
			title: upload.title,
			description: upload.description,
			tags: settings.tags,
			categoryId: settings.categoryId ?? "22",
		},
		status: {
			privacyStatus: upload.scheduledAt
				? "private"
				: (settings.privacyStatus ?? "public"),
			publishAt: upload.scheduledAt?.toISOString(),
			license: settings.license ?? "youtube",
			selfDeclaredMadeForKids: settings.madeForKids ?? false,
			containsSyntheticMedia: settings.containsSyntheticMedia ?? false,
		},
	};
	const init = await fetch(
		"https://www.googleapis.com/upload/youtube/v3/videos?uploadType=resumable&part=snippet,status",
		{
			method: "POST",
			headers: {
				Authorization: `Bearer ${token}`,
				"Content-Type": "application/json; charset=UTF-8",
				"X-Upload-Content-Type": upload.mimeType,
				"X-Upload-Content-Length": String(upload.size),
			},
			body: JSON.stringify(body),
		},
	);
	if (!init.ok)
		throw new Error(`YouTube upload initialization failed (${init.status}).`);
	const location = init.headers.get("location");
	if (!location) throw new Error("YouTube did not return an upload URL.");
	const video = await readFile(upload.videoPath);
	const result = await fetch(location, {
		method: "PUT",
		headers: {
			Authorization: `Bearer ${token}`,
			"Content-Type": upload.mimeType,
			"Content-Length": String(video.byteLength),
		},
		body: video,
	});
	if (!result.ok) throw new Error(`YouTube upload failed (${result.status}).`);
	const data = (await result.json()) as { id?: string };
	if (!data.id) throw new Error("YouTube did not return a video ID.");
	if (upload.thumbnailPath) {
		const thumbnail = await readFile(upload.thumbnailPath);
		const thumb = await fetch(
			`https://www.googleapis.com/upload/youtube/v3/thumbnails/set?videoId=${encodeURIComponent(data.id)}`,
			{
				method: "POST",
				headers: {
					Authorization: `Bearer ${token}`,
					"Content-Type": "image/jpeg",
					"Content-Length": String(thumbnail.byteLength),
				},
				body: thumbnail,
			},
		);
		if (!thumb.ok)
			throw new Error(`YouTube thumbnail upload failed (${thumb.status}).`);
	}
	return { id: data.id, url: `https://www.youtube.com/watch?v=${data.id}` };
}

async function publishTiktok(upload: typeof videoUploads.$inferSelect) {
	const token = await getTiktokAccessToken();
	if (!token) throw new Error("TikTok OAuth is not configured.");
	const settings = upload.tiktokSettings as TiktokSettings;
	const creatorResponse = await fetch(
		"https://open.tiktokapis.com/v2/post/publish/creator_info/query/",
		{ headers: { Authorization: `Bearer ${token}` } },
	);
	if (!creatorResponse.ok)
		throw new Error("TikTok creator information lookup failed.");
	const creator = (await creatorResponse.json()) as {
		data?: { privacy_level_options?: string[] };
	};
	const privacy =
		settings.privacyLevel ??
		creator.data?.privacy_level_options?.[0] ??
		"SELF_ONLY";
	const video = await readFile(upload.videoPath);
	const chunkSize = Math.min(10 * 1024 * 1024, video.byteLength);
	const init = await fetch(
		"https://open.tiktokapis.com/v2/post/publish/video/init/",
		{
			method: "POST",
			headers: {
				Authorization: `Bearer ${token}`,
				"Content-Type": "application/json; charset=UTF-8",
			},
			body: JSON.stringify({
				post_info: {
					title: upload.title,
					privacy_level: privacy,
					disable_comment: settings.disableComment ?? false,
					disable_duet: settings.disableDuet ?? false,
					disable_stitch: settings.disableStitch ?? false,
					video_cover_timestamp_ms: settings.coverTimestampMs ?? 0,
					brand_content_toggle: settings.brandContentToggle ?? false,
					brand_organic_toggle: settings.brandOrganicToggle ?? false,
					is_aigc: settings.isAigc ?? false,
				},
				source_info: {
					source: "FILE_UPLOAD",
					video_size: video.byteLength,
					chunk_size: chunkSize,
					total_chunk_count: Math.ceil(video.byteLength / chunkSize),
				},
			}),
		},
	);
	if (!init.ok)
		throw new Error(`TikTok upload initialization failed (${init.status}).`);
	const initData = (await init.json()) as {
		data?: { publish_id?: string; upload_url?: string };
	};
	const uploadUrl = initData.data?.upload_url;
	if (!uploadUrl || !initData.data?.publish_id)
		throw new Error("TikTok did not return an upload ticket.");
	for (let start = 0; start < video.byteLength; start += chunkSize) {
		const end = Math.min(start + chunkSize, video.byteLength) - 1;
		const result = await fetch(uploadUrl, {
			method: "PUT",
			headers: {
				"Content-Type": upload.mimeType,
				"Content-Length": String(end - start + 1),
				"Content-Range": `bytes ${start}-${end}/${video.byteLength}`,
			},
			body: video.subarray(start, end + 1),
		});
		if (!result.ok)
			throw new Error(`TikTok video transfer failed (${result.status}).`);
	}
	return { id: initData.data.publish_id, url: "https://www.tiktok.com/" };
}

export async function publishVideoJob(jobId: string) {
	const job = await db.query.videoUploadJobs.findFirst({
		where: (table, { eq }) => eq(table.id, jobId),
	});
	if (!job || job.status === "completed") return;
	const upload = await db.query.videoUploads.findFirst({
		where: (table, { eq }) => eq(table.id, job.uploadId),
	});
	if (!upload) throw new Error("Upload record not found.");
	await db
		.update(videoUploadJobs)
		.set({
			status: "processing",
			attempts: job.attempts + 1,
			startedAt: new Date(),
			error: null,
		})
		.where(eq(videoUploadJobs.id, job.id));
	try {
		const result =
			job.platform === "youtube"
				? await publishYoutube(upload)
				: await publishTiktok(upload);
		await db
			.update(videoUploadJobs)
			.set({
				status: "completed",
				externalId: result.id,
				externalUrl: result.url,
				completedAt: new Date(),
			})
			.where(eq(videoUploadJobs.id, job.id));
	} catch (error) {
		const message =
			error instanceof Error ? error.message : "Platform upload failed.";
		await db
			.update(videoUploadJobs)
			.set({ status: "failed", error: message })
			.where(eq(videoUploadJobs.id, job.id));
		throw error;
	}
}

export async function processDueVideoUploads() {
	const due = await db.query.videoUploads.findMany({
		where: (table, { eq, lte, or, isNull }) =>
			and(
				or(eq(table.status, "scheduled"), eq(table.status, "partial")),
				or(isNull(table.scheduledAt), lte(table.scheduledAt, new Date())),
			),
		orderBy: [desc(videoUploads.createdAt)],
	});
	for (const upload of due) {
		const jobs = await db.query.videoUploadJobs.findMany({
			where: (table, { eq, and, ne }) =>
				and(eq(table.uploadId, upload.id), ne(table.status, "completed")),
		});
		for (const job of jobs)
			await publishVideoJob(job.id).catch(() => undefined);
		const remaining = await db.query.videoUploadJobs.findMany({
			where: (table, { eq, and, ne }) =>
				and(eq(table.uploadId, upload.id), ne(table.status, "completed")),
		});
		const nextStatus =
			remaining.length === 0
				? "completed"
				: remaining.some((job) => job.status === "completed")
					? "partial"
					: "failed";
		await db
			.update(videoUploads)
			.set({ status: nextStatus, updatedAt: new Date() })
			.where(eq(videoUploads.id, upload.id));
	}
}