const express = require('express');
const cors = require('cors');
const { spawn } = require('child_process');
const path = require('path');

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

const PORT = process.env.UPDATER_PORT || 4001;

// State to keep track of the current update process
let updateState = {
    status: 'idle', // idle, updating, success, error
    progress: 0,
    step: '',
    logs: []
};

function addLog(msg) {
    console.log(msg);
    updateState.logs.push(msg);
    if (updateState.logs.length > 100) {
        updateState.logs.shift(); // Keep last 100 logs
    }
}

function runCommand(command, args, stepName, progressStart, progressEnd) {
    return new Promise((resolve, reject) => {
        updateState.step = stepName;
        updateState.progress = progressStart;
        addLog(`>>> Exécution: ${command} ${args.join(' ')}`);

        const proc = spawn(command, args, { cwd: path.join(__dirname), shell: true });

        proc.stdout.on('data', (data) => {
            addLog(data.toString().trim());
        });

        proc.stderr.on('data', (data) => {
            addLog(`[ERREUR] ${data.toString().trim()}`);
        });

        proc.on('close', (code) => {
            if (code !== 0) {
                addLog(`>>> Échec avec le code ${code}`);
                reject(new Error(`La commande ${command} a échoué.`));
            } else {
                updateState.progress = progressEnd;
                addLog(`>>> Succès: ${stepName}`);
                resolve();
            }
        });
    });
}

app.get('/api/update/status', (req, res) => {
    res.json(updateState);
});

app.post('/api/update', async (req, res) => {
    if (updateState.status === 'updating') {
        return res.status(400).json({ error: 'Une mise à jour est déjà en cours.' });
    }

    updateState = {
        status: 'updating',
        progress: 10,
        step: 'Initialisation',
        logs: []
    };
    
    res.json({ message: 'Mise à jour démarrée' });

    try {
        // Step 1: Git Pull (10% to 30%)
        await runCommand('git', ['pull'], 'Téléchargement des sources (git pull)', 10, 30);
        
        // Step 2: NPM Install (30% to 60%)
        await runCommand('npm', ['install'], 'Installation des dépendances (npm install)', 30, 60);
        
        // Step 3: Build (60% to 100%)
        await runCommand('npm', ['run', 'build'], 'Compilation de l\'application (npm run build)', 60, 100);

        updateState.status = 'success';
        updateState.step = 'Terminé';
        updateState.progress = 100;
        addLog('>>> Mise à jour terminée avec succès.');
        
    } catch (error) {
        updateState.status = 'error';
        updateState.step = 'Erreur';
        addLog(`>>> ERREUR CRITIQUE: ${error.message}`);
    }
});

// Acknowledge update success and reset
app.post('/api/update/reset', (req, res) => {
    updateState = { status: 'idle', progress: 0, step: '', logs: [] };
    res.json({ message: 'Reset OK' });
});

app.listen(PORT, () => {
    console.log(`[Ferrovia Updater] Écoute sur le port ${PORT}`);
});