const express = require('express');
const Queue = require('bull');
const { spawn } = require('child_process');
const fs = require('fs');
const path = require('path');
const cors = require('cors');
const EventEmitter = require('events');
const axios = require('axios');
var mpdParser = require('mpd-parser');
const softwareService = require('./services/softwares');

const BASE_PATH = process.env.DATA_PATH || `./data`;
const OUTPUT_PATH = process.env.OUTPUT_PATH || `${BASE_PATH}/output`;
const TMP_PATH = `${BASE_PATH}/tmp`;

const app = express();
const port = 3000;

app.use(cors());
app.use(express.json());

const videoQueue = new Queue('crawlflix_queue', 'redis://192.168.1.222:32768');

videoQueue.on('error', (e) => {
	console.log('An error occured', e);
});

const runCommand = (command) => {
	console.log('⚙️  Will execute: ' + command);
	return new Promise((resolve, reject) => {
		const cmd = spawn(command, { shell: true });
		let lastLog = '';

		cmd.stdout.on('data', (data) => {
			lastLog = data.toString();
			process.stdout.write(data.toString());
		});

		cmd.stderr.on('data', (data) => {
			lastLog = data.toString();
			process.stderr.write(`stderr: ${data.toString()}`);
		});

		cmd.on('close', (code) => {
			if (code === 0) {
				resolve('Command executed successfully.');
			} else {
				reject(lastLog || 'Command failed with status code ' + code);
			}
		});
	});
};

const runProgressCommand = (command) => {
    console.log('⚙️  Will execute: ' + command);
    const emitter = new EventEmitter();

    const executeCommand = new Promise((resolve, reject) => {
        const cmd = spawn(command, { shell: true });
        let lastLog = '';

        cmd.stdout.on('data', (data) => {
        	lastLog = data.toString();
            const perc = extractPercentage(data.toString());
            if (!perc) {
                process.stdout.write(data.toString());
            } else {
                emitter.emit('percentage', perc);
            }
        });

        cmd.stderr.on('data', (data) => {
        	lastLog = data.toString();
            process.stderr.write(`stderr: ${data.toString()}`);
        });

        cmd.on('close', (code) => {
           	if (code === 0) {
				resolve('Command executed successfully.');
			} else {
				reject(lastLog || 'Command failed with status code ' + code);
			}
        });
    });

    return { executeCommand, emitter };
};

// Route pour démarrer le processus
app.post('/start-process', async (req, res, next) => {
	try {
		const { mp4Filename, mpdUrl, keys, wantedResolution, wantedAudioTracks, wantedSubtitles } = req.body;
		console.log(JSON.stringify(req.body, null, 2));
		const job = await videoQueue.add({
			mp4Filename,
			mpdUrl,
			keys,
			wantedResolution,
			wantedAudioTracks,
			wantedSubtitles
		});
		res.json({ jobId: job.id });
	} catch(e) {
		console.log(e);
		next();
	}
});

// Route pour vérifier le statut du job
app.get('/job-status/:jobId', async (req, res) => {
	const job = await videoQueue.getJob(req.params.jobId);
	if (job === null) {
		res.status(404).json({ error: 'Job not found' });
	} else {
		const state = await job.getState();
		const progress = job._progress;
		res.json({ jobId: job.id, state, progress });
	}
});

app.get('/jobs-status', async (req, res) => {
	const jobs = await videoQueue.getJobs();
	res.json(await Promise.all(jobs.splice(0, 25).map(async job => ({
		id: job.id,
		state: await job.getState(),
		progress: job._progress,
		addedOn: job.timestamp,
		processedOn: job.processedOn,
		finishedOn: job.finishedOn,
		returnValue: job.returnvalue,
		failedReason: job.failedReason,
		data: job.data
	}))));
});

app.get('/download/:filename', async (req, res) => {
	const { filename } = req.params;
	const file = path.join(process.cwd(), filename);
	res.download(file);
});

app.get('/hello', async (req, res, next) => {
	try {
		res.json({
			downloader: await softwareService.checkDownloaderUpdate(),
			mp4decrypt: await softwareService.checkMp4decryptUpdate()
		})
	} catch(e) {
		console.log(e);
		next(e);
	}
});

app.post('/processUpdate', async (req, res, next) => {
	try {
		console.log(req.body);
		await softwareService.processUpdate(req.body);
		res.end();
	} catch(e) {
		console.log(e);
		next(e);
	}
});

const checkFilesExistance = (pattern, path) => {
	return new Promise(async (resolve, reject) => {
		try {
			const files = fs.readdirSync(path);
			resolve(files.filter(file => file.includes(pattern)));
		} catch(e) {
			reject(e);
		}
	});
};

const extractPercentage = (line) => {
	const s = line.split('%');
	const percentages = [];

	for (let i = 0; i < s.length; i++) {
		if (s[i].length === 0) continue;
		const ss = s[i].split(' ');
		if (ss.length > 0 && !isNaN(ss[ss.length - 1]))
			percentages.push(parseFloat(ss[ss.length - 1]));
	}
	if (percentages.length === 0) return null;
	return Math.max(...percentages.filter((p) => p < 100));
}

const parseMPDStream = async (mpdUrl) => {
	const mpdResponse = await axios({
		url: mpdUrl,
		method: 'GET',
		responseType: 'text'
	});
	const eventHandler = ({ type, message }) => console.log(`${type}: ${message}`);

	const parsedManifest = mpdParser.parse(mpdResponse.data , { mpdUrl, eventHandler });
	
	const obj = {
		audioTracks: [],
		videoTracks: [],
		subtitles: []
	};
	const toParse = [{
		rootProp: 'AUDIO',
		subProp: 'audio',
		targetProp: 'audioTracks'
	}, {
		rootProp: 'SUBTITLES',
		subProp: 'subs',
		targetProp: 'subtitles'
	}]

	toParse.forEach(({ rootProp, subProp, targetProp }) => {
		for (const [key, value] of Object.entries(parsedManifest?.mediaGroups?.[rootProp]?.[subProp])) {
			for (let i = 0; i < value.playlists.length; i++) {
				obj[targetProp].push({
					name: key,
					language: value.language,
					attributes: value.playlists[i].attributes
				});
			}
		}
	});
	for (let i = 0; i < parsedManifest.playlists.length; i++) {
		obj.videoTracks.push({
			name: `${parsedManifest.playlists?.[i]?.attributes?.RESOLUTION?.width || 'N/C'}x${parsedManifest.playlists?.[i]?.attributes?.RESOLUTION?.height || 'N/C'}`,
			codec: parsedManifest.playlists?.[i]?.attributes?.CODECS,
			bandwidth: parsedManifest.playlists?.[i]?.attributes?.BANDWIDTH,
			fps: parsedManifest.playlists?.[i]?.attributes?.['FRAME-RATE'],
			resolution: {
				width: parsedManifest.playlists?.[i]?.attributes?.RESOLUTION?.width,
				height: parsedManifest.playlists?.[i]?.attributes?.RESOLUTION?.height
			}
		});
	}
	obj.videoTracks = obj.videoTracks.sort((a, b) => b.resolution.width - a.resolution.width);
	return obj;
};

app.post('/processMPD', async (req, res, next) => {
	try {
		res.json(await parseMPDStream(req.body.mpdUrl));
	} catch(e) {
		console.log(e);
		next(e);
	}
});

// Processus de la file d'attente
videoQueue.process((job) => {
	return new Promise(async (resolve, reject) => {
		try {
			console.log('Will launch job')
			const { mp4Filename, mpdUrl, keys, wantedResolution, wantedAudioTracks, wantedSubtitles } = job.data;
			const downloaderPath = softwareService.getLocalBinFileInfo('downloader').path;
			const mp4decryptPath = softwareService.getLocalBinFileInfo('mp4decrypt').path;

			const workdir = path.join(TMP_PATH, mp4Filename);
			if (!fs.existsSync(workdir))
				fs.mkdirSync(workdir);
			const mp4FilenameWithExt= `${mp4Filename}.mp4`;
			const finalPath = path.join(OUTPUT_PATH, mp4Filename);

			const filesExist = await checkFilesExistance('encrypted', workdir);
			if (filesExist.length === 0) {
				console.log('Encrypted files not found, downloading...');
				let objectsDownloaded = -1, previousPercentage = -1;
				const objectsToDownload = 1 + wantedAudioTracks.length + wantedSubtitles.length;
				job.progress(10);  // Début à 10%

				const bwAudio = wantedAudioTracks.length === 1 ? `:bwMin=\"${wantedAudioTracks.map(elem => Math.floor(elem.attributes.BANDWIDTH / 1000 -1)).join('|')}\":bwMax=\"${wantedAudioTracks.map(elem => Math.round(elem.attributes.BANDWIDTH / 1000 + 1)).join('|')}\"` : '';
				const bwSubs = wantedSubtitles.length === 1 ? `:bwMin=\"${wantedSubtitles.map(elem => Math.floor(elem.attributes.BANDWIDTH / 1000 -1)).join('|')}\":bwMax=\"${wantedSubtitles.map(elem => Math.round(elem.attributes.BANDWIDTH / 1000 + 1)).join('|')}\"` : '';

				const subPart = wantedSubtitles.length > 0 ? `--select-subtitle lang=\"${wantedSubtitles.map(elem => elem.language).join('|')}\"${bwSubs}` : '--drop-subtitle lang=\".*\"';
				const audioPart = wantedAudioTracks.length > 0 ? `--select-audio lang=\"${wantedAudioTracks.map(elem => elem.language).join('|')}\":codecs=\"${[...new Set(wantedAudioTracks.map(elem => elem.attributes.CODECS))].join('|')}\":for=all${bwAudio}` : '--drop-audio lang=\".*\"';

				const { executeCommand, emitter } = runProgressCommand(`${downloaderPath} \"${mpdUrl}\" --save-dir ${workdir} --save-name ${mp4Filename}_encrypted --select-video res=\"${wantedResolution.resolution.width}*\" ${audioPart} ${subPart}`, true);

				emitter.on('percentage', (percentage) => {
				    if (percentage < previousPercentage) {
				        objectsDownloaded++;
				    }
				    previousPercentage = percentage;

				    const subPercMax = 50 / objectsToDownload;
				    job.progress(Math.round((10 + (objectsDownloaded * subPercMax)) + (percentage * subPercMax / 100)));
				});

				await executeCommand;
			} else {
				console.log('Encrypted files already exist, bypassing download...')
			}
			job.progress(60);

			// Decrypt video stream
			await runCommand(`${mp4decryptPath} ${keys.map(k => `--key ${k.key}:${k.value}`).join(' ')} "${workdir}/${mp4Filename}_encrypted.mp4" "${workdir}/${mp4Filename}_decrypted.mp4"`);

			job.progress(70);

			// Decrypt audio streams
			const audioFiles = fs.readdirSync(workdir);
			const finalAudio = [];
			for (const file of audioFiles) {
				if (file.startsWith(`${mp4Filename}_encrypted`) && file.endsWith('.m4a')) {
					const baseName = path.basename(file, '.m4a');
					await runCommand(`${mp4decryptPath} ${keys.map(k => `--key ${k.key}:${k.value}`).join(' ')} "${workdir}/${file}" "${workdir}/${baseName}_decrypted.m4a"`);
					finalAudio.push(`${workdir}/${baseName}_decrypted.m4a`);
				}
			}

			job.progress(80);

			// Combinaison avec ffmpeg
			let ffmpegCommand = `ffmpeg -y -i ${workdir}/${mp4Filename}_decrypted.mp4`;
			let mapCommand = ' -map 0:v';
			let inputIndex = 1;

			for (const file of finalAudio) {
				ffmpegCommand += ` -i ${file}`;
				mapCommand += ` -map ${inputIndex}:a`;
				inputIndex++;
			}

			if (!fs.existsSync(finalPath))
				fs.mkdirSync(finalPath);

			ffmpegCommand += `${mapCommand} -c copy ${finalPath}/${mp4FilenameWithExt}`;
			await runCommand(ffmpegCommand);

			job.progress(90);

			// Renommage des fichiers SRT
			const subFiles = fs.readdirSync(workdir);
			let counter = 1;
			for (const file of subFiles) {
				if (file.startsWith(`${mp4Filename}_encrypted`) && file.endsWith('.srt')) {
					fs.renameSync(`${workdir}/${file}`, `${finalPath}/${mp4Filename}_${counter}.srt`);
					counter++;
				}
			}

			// Nettoyage (commenté pour correspondre au script original)
			await runCommand(`rm -fr ${workdir}`);

			job.progress(100);
			resolve({ message: `File fetched and decrypted with success: ${mp4Filename}.mp4`, filePath: `${OUTPUT_PATH}/${mp4Filename}.mp4`, fileName: `${mp4Filename}.mp4` });
		} catch (error) {
			console.log('Error while processing task', error)
			reject(new Error(`${error.toString() || error}`));
		}
	});
});

app.listen(port, () => {
	console.log(`Server running at http://localhost:${port}`);
	const dirsToCheck = [{
		path: BASE_PATH,
		name: 'data'
	}, {
		path: OUTPUT_PATH,
		name: 'output'
	}, {
		path: TMP_PATH,
		name: 'tmp'
	}];

	for (let i = 0; i < dirsToCheck.length; i++) {
		const dir = dirsToCheck[i];
		if (!fs.existsSync(dir.path)) {
			console.log(`Creating ${dir.name} directory...`);
			fs.mkdirSync(dir.path);
		}
	}
	
	softwareService.init();

});