console.log(`started @ ${new Date().toISOString()}`);

import { encode } from "blurhash";
import mime from 'mime/lite';
import sharp from "sharp";
import exitHook from 'exit-hook';
import { execFileSync, spawnSync } from "child_process";
import { watch, existsSync, readdirSync, readFileSync, writeFileSync, unlinkSync } from "fs";
import { join } from "path";
import { access_token, homeserver, folder2room } from "./config.js";

exitHook(signal => {
	console.log(`stopped @ ${new Date().toISOString()} signal ${signal}`);
	unlinkSync("pid.txt");
});

writeFileSync("pid.txt", String(process.pid));


async function fetch(url, options) {
	while (!res?.ok) {
		try {
			console.debug("fetch", url);
			var res = await global.fetch(url, options);
			if (!res.ok) throw new Error(`HTTP ${res.status}, ${await res.text()}`);
		} catch (error) {
			console.error("fetch:", error.message);
		}
		await new Promise(r => setTimeout(r, 30000));
	}
	return res;
}



//todo use win32 api

function fileIdToPath(fileId) {
	var out = execFileSync("fsutil", ["file", "queryFileNameById", "C:", fileId]).toString().trim();
	var path = out.slice(out.indexOf("\\\\"));
	//console.debug(`${fileId} = ${path}`);
	return path;
}

function filePathToId(filePath) {
	var out = execFileSync("fsutil", ["file", "queryFileId", filePath]).toString().trim();
	var id = BigInt(out.slice(out.indexOf("0x")));
	//console.debug(`${filePath} = ${id}`);
	return id;
}



folder2room.forEach((roomId, folderId) => {
	console.log(`loading ids for ${roomId}`);
	var folderPath = fileIdToPath(folderId);
	var existingFiles = readdirSync(folderPath).map(fileName => filePathToId(join(folderPath, fileName)));
	console.log(`${existingFiles.length} files`);
	watch(folderPath, async (eventType, fileName) => {
		try {
			console.log(eventType, folderPath, fileName);
			if (eventType != "rename") return;
			if (fileName.endsWith(".crdownload")) return;

			var filePath = join(folderPath, fileName);
			if (!existsSync(filePath)) return;
			var fileId = filePathToId(filePath);
			if (existingFiles.includes(fileId)) return;
			existingFiles.push(fileId);

			var mimetype = mime.getType(filePath) || "application/octet-stream";
			await postImageOnMatrix(roomId, filePath, fileName, mimetype);
		} catch (error) {
			console.error(error.stack);
		}
	});
});

console.log("ready");



async function postImageOnMatrix(roomId, filePath, fileName, mimetype) {
	console.log(`Posting ${filePath} to room ${roomId}`);
	var file = readFileSync(filePath);
	if (mimetype.startsWith("image/")) {
		var {data, info} = await sharp(file).ensureAlpha().raw().toBuffer({resolveWithObject: true});
		var blurhash = encode(
			new Uint8ClampedArray(data),
			info.width,
			info.height,
			// https://github.com/element-hq/element-web/blob/7dbffb348dfe8fbd83c9ea4bff9f37292b0979bb/src/workers/blurhash.worker.ts#L29-L31
			info.width >= info.height ? 4 : 3,
			info.height >= info.width ? 4 : 3,
		);
	} else if (mimetype.startsWith("video/")) {
		let {stdout, stderr} = spawnSync("ffmpeg", ["-i", filePath, "-frames:v", "1", "-f", "webp", "-c:v", "libwebp", "-"]);
		stderr = stderr.toString();
		console.debug(stderr);
		var duration = stderr.match(/Duration: (\d{2}):(\d{2}):(\d{2})\.(\d{2})/);
		if (duration) {
			duration = parseInt(duration[1]) * 3600 + parseInt(duration[2]) * 60 + parseInt(duration[3]) + parseInt(duration[4]) / 100;
			duration = duration * 1000;
			console.debug(`Duration: ${duration} ms`);
		}
		var {data, info} = await sharp(stdout).ensureAlpha().raw().toBuffer({resolveWithObject: true});
		var thumbnail_info = {
			w: info.width,
			h: info.height,
			mimetype: "image/webp",
			size: stdout.length,
		}
		var blurhash = encode(
			new Uint8ClampedArray(data),
			info.width,
			info.height,
			// https://github.com/element-hq/element-web/blob/7dbffb348dfe8fbd83c9ea4bff9f37292b0979bb/src/workers/blurhash.worker.ts#L29-L31
			info.width >= info.height ? 4 : 3,
			info.height >= info.width ? 4 : 3,
		);
		var thumbnail_url = await uploadFile(fileName + ".webp", stdout, "image/webp");
	} else if (mimetype.startsWith("audio/")) {
		// todo get duration
	}

	var content_uri = await uploadFile(fileName, file, mimetype);
	var txnId = Math.random();
	var res = await fetch(`${homeserver}/_matrix/client/v3/rooms/${encodeURIComponent(roomId)}/send/m.room.message/${txnId}`, {
		method: "PUT",
		headers: {
			"Authorization": `Bearer ${access_token}`,
			"Content-Type": "application/json",
		},
		body: JSON.stringify({
			"msgtype": mimetype.startsWith("image/") ? "m.image" : mimetype.startsWith("video/") ? "m.video" : mimetype.startsWith("audio/") ? "m.audio" : "m.file",
			"body": fileName,
			"info": {
				"xyg.amorgan.blurhash": blurhash,
				"mimetype": mimetype,
				"w": info?.width,
				"h": info?.height,
				"size": file.length,
				thumbnail_info,
				thumbnail_url,
				duration
			},
			"url": content_uri,
		})
	});
	var {event_id} = await res.json();
	console.log(event_id);
	//todo store mapping
}


async function uploadFile(fileName, file, mimetype) {
	var res = await fetch(`${homeserver}/_matrix/media/v3/upload?filename=${encodeURIComponent(fileName)}`, {
		method: "POST",
		headers: {
			"Authorization": `Bearer ${access_token}`,
			"Content-Type": mimetype,
		},
		body: file
	});
	var {content_uri} = await res.json();
	console.debug(content_uri);
	return content_uri;
}