/**
 * VEditor Render Server
 * 
 * Standalone Express API for video rendering using Remotion.
 * Designed for deployment on Hugging Face Spaces (port 7860).
 */

import express from 'express';
import cors from 'cors';
import path from 'path';
import fs from 'fs';
import { v4 as uuidv4 } from 'uuid';
import { renderVideo } from './render';

const app = express();
const PORT = process.env.PORT || 7860;
const VIDEOS_DIR = path.join(process.cwd(), 'videos');
const JOBS_DIR = path.join(process.cwd(), 'jobs');

// Ensure directories exist
[VIDEOS_DIR, JOBS_DIR].forEach(dir => {
    if (!fs.existsSync(dir)) {
        fs.mkdirSync(dir, { recursive: true });
    }
});

// Middleware
app.use(cors());
app.use(express.json({ limit: '50mb' }));
app.use('/videos', express.static(VIDEOS_DIR));

// Health check
app.get('/', (req, res) => {
    res.json({
        status: 'ok',
        service: 'VEditor Render Server',
        version: '1.0.0'
    });
});

// Start render job
app.post('/render', async (req, res) => {
    try {
        const { design, options } = req.body;

        if (!design) {
            return res.status(400).json({ error: 'Design is required' });
        }

        const jobId = `job_${Date.now()}_${uuidv4().substring(0, 8)}`;
        const jobFile = path.join(JOBS_DIR, `${jobId}.json`);
        const statusFile = path.join(JOBS_DIR, `${jobId}.status.json`);

        // Save job data
        fs.writeFileSync(jobFile, JSON.stringify({ design, options }, null, 2));
        fs.writeFileSync(statusFile, JSON.stringify({
            status: 'pending',
            progress: 0
        }));

        console.log(`[Render] Starting job: ${jobId}`);

        // Start render in background
        renderVideo(jobId, design, options || {})
            .then((firebaseUrl) => {
                // Recalculate path to ensure correct file is updated
                const completedStatusFile = path.join(JOBS_DIR, `${jobId}.status.json`);
                const completedData = JSON.stringify({
                    status: 'completed',
                    progress: 100,
                    outputUrl: firebaseUrl
                });

                try {
                    fs.writeFileSync(completedStatusFile, completedData);
                    console.log(`[Render] Status file updated: ${completedStatusFile}`);
                    console.log(`[Render] Status data: ${completedData}`);
                    console.log(`[Render] Completed: ${jobId} -> ${firebaseUrl}`);
                } catch (writeError) {
                    console.error(`[Render] Failed to write status file:`, writeError);
                }
            })
            .catch((error) => {
                console.error(`[Render] Failed: ${jobId}`, error);
                const failedStatusFile = path.join(JOBS_DIR, `${jobId}.status.json`);
                try {
                    fs.writeFileSync(failedStatusFile, JSON.stringify({
                        status: 'failed',
                        progress: 0,
                        error: error.message || 'Unknown error'
                    }));
                } catch (writeError) {
                    console.error(`[Render] Failed to write error status:`, writeError);
                }
            });

        res.status(202).json({
            jobId,
            status: 'pending',
            statusUrl: `/render/${jobId}`
        });

    } catch (error) {
        console.error('[Render] Error:', error);
        res.status(500).json({ error: 'Internal server error' });
    }
});

// Check render status
app.get('/render/:jobId', (req, res) => {
    const { jobId } = req.params;
    const statusFile = path.join(JOBS_DIR, `${jobId}.status.json`);

    if (!fs.existsSync(statusFile)) {
        return res.status(404).json({ error: 'Job not found' });
    }

    const status = JSON.parse(fs.readFileSync(statusFile, 'utf-8'));
    res.json({ jobId, ...status });
});

// List all jobs
app.get('/jobs', (req, res) => {
    const files = fs.readdirSync(JOBS_DIR).filter(f => f.endsWith('.status.json'));
    const jobs = files.map(f => {
        const jobId = f.replace('.status.json', '');
        const status = JSON.parse(fs.readFileSync(path.join(JOBS_DIR, f), 'utf-8'));
        return { jobId, ...status };
    });
    res.json(jobs);
});

// Start server
app.listen(PORT, () => {
    console.log(`🎬 VEditor Render Server running on port ${PORT}`);
    console.log(`📁 Videos directory: ${VIDEOS_DIR}`);
    console.log(`📋 Jobs directory: ${JOBS_DIR}`);
});