class VideoDubbingApp {
    constructor() {
        this.initializeElements();
        this.bindEvents();
        this.notificationManager = new NotificationManager();
    }

    initializeElements() {
        this.videoUrlInput = document.getElementById('videoUrl');
        this.generateBtn = document.getElementById('generateBtn');
        this.loadingSection = document.getElementById('loadingSection');
        this.outputSection = document.getElementById('outputSection');
        this.dubbedVideo = document.getElementById('dubbedVideo');
        this.downloadBtn = document.getElementById('downloadBtn');
        this.hindiTranscript = document.getElementById('hindiTranscript');
        this.playBtn = document.getElementById('playBtn');
        this.pauseBtn = document.getElementById('pauseBtn');
        this.restartBtn = document.getElementById('restartBtn');
        this.addSubtitlesCheckbox = document.getElementById('addSubtitles');
        this.voiceStyleSelect = document.getElementById('voiceStyle');
        this.targetLanguageSelect = document.getElementById('targetLanguage');
    }

    bindEvents() {
        this.generateBtn.addEventListener('click', () => this.handleGenerate());
        this.downloadBtn.addEventListener('click', () => this.handleDownload());
        this.playBtn.addEventListener('click', () => this.playVideo());
        this.pauseBtn.addEventListener('click', () => this.pauseVideo());
        this.restartBtn.addEventListener('click', () => this.restartVideo());
    }

    async handleGenerate() {
        const videoUrl = this.videoUrlInput.value.trim();
        
        if (!videoUrl) {
            this.notificationManager.show('Please enter a valid YouTube URL', 'error');
            return;
        }

        if (!this.isValidYouTubeUrl(videoUrl)) {
            this.notificationManager.show('Please enter a valid YouTube URL', 'error');
            return;
        }

        this.showLoading();
        
        try {
            // Simulate processing time
            await this.simulateProcessing();
            this.showOutput();
            this.notificationManager.show('Video processing completed successfully!', 'success');
        } catch (error) {
            this.hideLoading();
            this.notificationManager.show('Error processing video. Please try again.', 'error');
        }
    }

    isValidYouTubeUrl(url) {
        const youtubeRegex = /^(https?\:\/\/)?(www\.)?(youtube\.com|youtu\.be)\/.+/;
        return youtubeRegex.test(url);
    }

    showLoading() {
        this.loadingSection.style.display = 'block';
        this.outputSection.style.display = 'none';
        this.generateBtn.disabled = true;
    }

    hideLoading() {
        this.loadingSection.style.display = 'none';
        this.generateBtn.disabled = false;
    }

    async simulateProcessing() {
        // Simulate API calls and processing time
        return new Promise(resolve => {
            setTimeout(resolve, 3000);
        });
    }

    showOutput() {
        this.hideLoading();
        this.outputSection.style.display = 'block';
        
        // Set demo transcript based on selected language
        const selectedLanguage = this.targetLanguageSelect.value;
        const demoTranscripts = {
            hindi: 'यह एक डेमो हिंदी ट्रांसक्रिप्ट है। वास्तविक एप्लिकेशन में, यह वीडियो से ट्रांसक्राइब और अनुवादित टेक्स्ट होगा।',
            tamil: 'இது ஒரு டெமோ தமிழ் டிரான்ஸ்கிரிப்ட் ஆகும். உண்மையான பயன்பாட்டில், இது வீடியோவில் இருந்து டிரான்ஸ்கிரைப் செய்யப்பட்ட மற்றும் மொழிபெயர்க்கப்பட்ட உரையாக இருக்கும்.',
            bengali: 'এটি একটি ডেমো বাংলা ট্রান্সক্রিপ্ট। প্রকৃত অ্যাপ্লিকেশনে, এটি ভিডিও থেকে ট্রান্সক্রিপ্ট এবং অনুবাদিত টেক্সট হবে।',
            telugu: 'ఇది ఒక డెమో తెలుగు ట్రాన్స్‌క్రిప్ట్. వాస్తవ అప్లికేషన్‌లో, ఇది వీడియో నుండి ట్రాన్స్‌క్రైబ్ చేయబడిన మరియు అనువదించబడిన టెక్స్ట్ అవుతుంది.',
            marathi: 'हे एक डेमो मराठी ट्रान्स्क्रिप्ट आहे. वास्तविक अनुप्रयोगात, हे व्हिडिओमधून ट्रान्सक्राइब केलेले आणि भाषांतरित मजकूर असेल।'
        };
        
        this.hindiTranscript.value = demoTranscripts[selectedLanguage] || demoTranscripts.hindi;
        
        // Set demo video source (placeholder)
        this.dubbedVideo.src = 'data:video/mp4;base64,';
    }

    handleDownload() {
        this.notificationManager.show('Download functionality would be implemented here', 'info');
    }

    playVideo() {
        if (this.dubbedVideo.src) {
            this.dubbedVideo.play();
        } else {
            this.notificationManager.show('No video available to play', 'warning');
        }
    }

    pauseVideo() {
        this.dubbedVideo.pause();
    }

    restartVideo() {
        this.dubbedVideo.currentTime = 0;
        this.dubbedVideo.play();
    }
}

class NotificationManager {
    constructor() {
        this.container = this.createContainer();
    }

    createContainer() {
        const container = document.createElement('div');
        container.style.cssText = `
            position: fixed;
            top: 20px;
            right: 20px;
            z-index: 10000;
            max-width: 300px;
        `;
        document.body.appendChild(container);
        return container;
    }

    show(message, type = 'info') {
        const notification = document.createElement('div');
        notification.style.cssText = `
            background: ${this.getNotificationColor(type)};
            color: white;
            padding: 15px 20px;
            border-radius: 8px;
            margin-bottom: 10px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.2);
            animation: slideIn 0.3s ease-out;
            display: flex;
            align-items: center;
            gap: 10px;
        `;
        
        notification.innerHTML = `
            <i class="fas fa-${this.getNotificationIcon(type)}"></i>
            <span>${message}</span>
        `;
        
        this.container.appendChild(notification);
        
        setTimeout(() => {
            notification.style.animation = 'slideOut 0.3s ease-in';
            setTimeout(() => {
                if (notification.parentNode) {
                    notification.parentNode.removeChild(notification);
                }
            }, 300);
        }, 3000);
    }

    getNotificationIcon(type) {
        const icons = {
            success: 'check-circle',
            error: 'exclamation-circle',
            info: 'info-circle',
            warning: 'exclamation-triangle'
        };
        return icons[type] || 'info-circle';
    }

    getNotificationColor(type) {
        const colors = {
            success: '#28a745',
            error: '#dc3545',
            info: '#17a2b8',
            warning: '#ffc107'
        };
        return colors[type] || '#17a2b8';
    }
}

// Add CSS animations for notifications
const style = document.createElement('style');
style.textContent = `
    @keyframes slideIn {
        from {
            transform: translateX(100%);
            opacity: 0;
        }
        to {
            transform: translateX(0);
            opacity: 1;
        }
    }
    
    @keyframes slideOut {
        from {
            transform: translateX(0);
            opacity: 1;
        }
        to {
            transform: translateX(100%);
            opacity: 0;
        }
    }
`;
document.head.appendChild(style);

// Initialize the app when DOM is loaded
document.addEventListener('DOMContentLoaded', () => {
    new VideoDubbingApp();
});

// Add some demo data for testing
window.addEventListener('load', () => {
    console.log('🎬 AI Video Dubbing App Loaded');
    console.log('📝 This is a demo interface. In production, it would integrate with:');
    console.log('   • YouTube API for video downloading');
    console.log('   • Speech-to-text API for transcription');
    console.log('   • Translation API for language conversion');
    console.log('   • Text-to-speech API for voice synthesis');
    console.log('   • Video processing for audio replacement');
});