import { StatusMap } from "elysia";
import { fileTypeFromFile } from "file-type";
import type { FileListingWithStatus, Metadata } from "music-server-shared/types";
import { readdir, stat } from "node:fs/promises";
import path from "node:path";
import {
	coverRegex,
	excludeExtension,
	fileTypeCache,
	mediaInfoDisabled,
	mediaTypes,
	musicRoot,
	PathInfo,
	probeCache,
	ServerError,
} from "./shared";
import { parseFile } from "music-metadata";
import tmp from "tmp";
import { readFileSync, writeFileSync } from "node:fs";
import MediaInfo from "mediainfo.js";

export async function findAsync<T>(arr: Array<T>, asyncCallback: (value: T) => Promise<boolean>) {
	const promises = arr.map(asyncCallback);
	const results = await Promise.all(promises);
	const index = results.findIndex((result) => result);
	return arr[index];
}

type CoverResult = { info: PathInfo; path: string } | { info: PathInfo; content: Uint8Array } | { info: ServerError };

const mediaInfo = await MediaInfo();

export async function findCover(targetPath: string): Promise<CoverResult> {
	try {
		if ((await stat(targetPath)).isFile()) {
			const parsed = await parseFile(targetPath, { duration: true, skipCovers: false });
			if (!parsed.common.picture || parsed.common.picture.length === 0) return findCover(path.dirname(targetPath));

			return { info: new PathInfo(parsed.common.picture[0].format), content: parsed.common.picture[0].data };
		}
	} catch (e) {
		return { info: new ServerError(StatusMap["Internal Server Error"], `error getting cover ${e}`) };
	}

	if (!coverRegex) return { info: new ServerError(StatusMap["Not Found"], "Cover not found") };
	let coverFile: string | undefined;
	try {
		coverFile = await findAsync(await readdir(targetPath), async (file) => {
			return file.match(coverRegex) != null && (await stat(path.join(targetPath, file))).isFile();
		});
		const above = path.dirname(targetPath);
		if (!coverFile && isBelow(musicRoot, above)) {
			return findCover(above);
		}
		// biome-ignore lint/suspicious/noExplicitAny:
	} catch (error: any) {
		if (error?.code !== "ENOENT") {
			console.error("error getting cover: readdirSync failed:", error);
			return { info: new ServerError(StatusMap["Internal Server Error"], "error getting cover: readdirSync failed") };
		}
		return { info: new ServerError(StatusMap["Not Found"], "Directory not found") };
	}
	if (coverFile) {
		const info = (await getPathInfo(path.join(targetPath, coverFile))) as PathInfo | ServerError;
		if (info instanceof ServerError) {
			return { info: info };
		}
		return { path: path.join(targetPath, coverFile), info };
	}
	return { info: new ServerError(StatusMap["Not Found"], "Cover not found") };
}

export async function probeFile(filePath: string): Promise<Metadata> {
	const cached = probeCache.get(filePath);
	if (cached) return cached;
	const parsed = await parseFile(filePath, { duration: true, skipCovers: false });

	let probeData: Metadata = {
		duration: parsed.format.duration || 0,
		title: parsed.common.title,
		artist: parsed.common.artist,
		album: parsed.common.album,
		genre: parsed.common.genre,
		trackNumber: parsed.common.track.no || undefined,
	};

	if (!mediaInfoDisabled) {
		const file = Bun.file(filePath);
		const fileSize = (await file.stat()).size;
		const chunkReader = async (size: number, offset: number) => {
			return await file.slice(offset, offset + size).bytes();
		};
		const info = await mediaInfo.analyzeData(fileSize, chunkReader);
		probeData = {
			...probeData,
			audioCodec: info.media?.track.find((track) => track["@type"] === "Audio")?.Format,
			audioBitrate: info.media?.track.find((track) => track["@type"] === "Audio")?.BitRate,
			videoCodec: info.media?.track.find((track) => track["@type"] === "Video")?.Format,
			videoBitrate: info.media?.track.find((track) => track["@type"] === "Video")?.BitRate,
			container: info.media?.track.find((track) => track["@type"] === "General")?.Format,
		};
	}
	probeCache.set(filePath, probeData);
	return probeData;
}

export async function getPathInfo(filePath: string): Promise<PathInfo | ServerError | undefined> {
	try {
		if (excludeExtension.includes(path.extname(filePath).slice(1))) return new ServerError(404, "Excluded extension");
		const stats = await stat(filePath);
		if (stats.isDirectory()) {
			return undefined;
		}
		let mimeType = fileTypeCache.get(filePath);
		if (!mimeType) {
			const type = await fileTypeFromFile(filePath);
			mimeType = type?.mime;
			if (mimeType) {
				fileTypeCache.set(filePath, mimeType);
			} else {
				console.error("Failed to determine MIME type for:", filePath);
				return new ServerError(StatusMap["Internal Server Error"], "Filetype scan failed");
			}
		}
		return new PathInfo(mimeType);
		// biome-ignore lint/suspicious/noExplicitAny:
	} catch (error: any) {
		if (error?.code === "ENOENT") {
			return new ServerError(StatusMap["Not Found"], "File not found");
		}
		console.error("Error scanning file:", filePath, error.message);
		return new ServerError(StatusMap["Internal Server Error"], "Internal Server Error");
	}
}

export function matchesType(mimeType: string, types: string[]): boolean {
	return types.includes(mimeType.split("/", 1)[0]);
}

export function isBelow(basePath: string, targetPath: string) {
	const relativePath = path.relative(basePath, targetPath);
	return relativePath && !relativePath.startsWith("..");
}

export async function listFiles(subPath: string, recursive: boolean): Promise<FileListingWithStatus | ServerError> {
	const files: FileListingWithStatus = new Map();

	try {
		for (const fileName of await readdir(subPath)) {
			const itemPath = path.join(subPath, fileName);
			if (!isBelow(musicRoot, itemPath)) {
				console.log(`Skipping ${itemPath} as it is outside the base path.`);
				continue;
			}

			const pathInfoResult = await getPathInfo(itemPath);
			if (!pathInfoResult) {
				if (recursive) {
					const subListing = await listFiles(itemPath, true);
					if (subListing instanceof ServerError) throw subListing;
					files.set(fileName, { files: subListing, status: "Scanned" });
				} else {
					files.set(fileName, { files: new Map(), status: "Unknown" });
				}
			} else if (pathInfoResult instanceof PathInfo && matchesType(pathInfoResult.mimeType, mediaTypes)) {
				try {
					const probe = await probeFile(itemPath);
					files.set(fileName, { metadata: probe });
				} catch (probeError) {
					console.error("probing error:", probeError);
				}
			}
		}
		return files;
		// biome-ignore lint/suspicious/noExplicitAny: <explanation>
	} catch (error: any) {
		if (error?.code === "ENOENT") {
			return new ServerError(StatusMap["Not Found"], "Directory not found");
		}
		console.error("Error listing path:", subPath, error.message);
		return new ServerError(StatusMap["Internal Server Error"], "Internal Server Error");
	}
}

export async function readStream(stream: ReadableStream<Uint8Array>): Promise<Uint8Array> {
	const reader = stream.getReader();
	const chunks: Uint8Array[] = [];

	try {
		while (true) {
			const { done, value } = await reader.read();
			if (done) break;
			if (value) chunks.push(value);
		}

		const combined = new Uint8Array(chunks.reduce((acc, chunk) => acc + chunk.length, 0));
		let offset = 0;
		for (const chunk of chunks) {
			combined.set(chunk, offset);
			offset += chunk.length;
		}

		return combined;
	} finally {
		reader.releaseLock();
	}
}

export function packWithTar(files: string[]) {
	// Ensure all files are within musicRoot
	const absoluteFiles = files.map((f) => path.join(musicRoot, f));
	for (const f of absoluteFiles) {
		if (!isBelow(musicRoot, f)) {
			throw new ServerError(StatusMap.Forbidden, "One or more files are outside the music root");
		}
	}

	const relFiles = absoluteFiles.map((f) => path.relative(musicRoot, f));
	const tarArgs = [
		"--transform=s|.*/||", //only supported in gnu tar TODO: add fallback
		"-C",
		musicRoot,
		"-c", // create archive
		...relFiles,
	];
	return Bun.spawn(["tar", ...tarArgs], {
		stdin: "ignore",
		stdout: "pipe",
		stderr: "pipe",
		onExit: async (subprocess: Bun.Subprocess<"ignore", "pipe", "pipe">, exitCode: number | null) => {
			if (exitCode !== 0 && exitCode !== null) {
				console.error("tar failed with status code", exitCode);
				console.error(new TextDecoder().decode(await readStream(subprocess.stderr as ReadableStream)));
			}
		},
	});
}

//copy to a temp file and then use avifenc to convert
export async function toAvif(
	data: Uint8Array,
	mimeType: string,
	setContentType: (mimeType: string) => void,
): Promise<Uint8Array> {
	const tmpFile = tmp.fileSync({
		postfix: mimeType.includes("image/jpeg") ? ".jpg" : mimeType.includes("image/jpeg") ? ".png" : undefined,
	});
	const tmpFile2 = tmp.fileSync({ postfix: ".avif" });
	try {
		writeFileSync(tmpFile.fd, data);
		const cmd = Bun.spawn(["avifenc", "-q", "50", tmpFile.name, tmpFile2.name], {
			stdin: "ignore",
			stdout: "pipe",
			stderr: "pipe",
			onExit: async (subprocess: Bun.Subprocess<"ignore", "pipe", "pipe">, exitCode: number | null) => {
				if (exitCode !== 0 && exitCode !== null) {
					console.error("avifenc failed with status code", exitCode);
					console.error(new TextDecoder().decode(await readStream(subprocess.stderr as ReadableStream)));
				}
			},
		});
		await cmd.exited;
		setContentType("image/avif");
		return readFileSync(tmpFile2.fd);
	} catch (e) {
		setContentType(mimeType);
		return data;
	} finally {
		tmpFile.removeCallback();
		tmpFile2.removeCallback();
	}
}