services/aiService.js

/**
 * خدمة الذكاء الاصطناعي - دعم نماذج متعددة
 * @version 3.0.0
 */

const axios = require('axios');
const crypto = require('crypto');

class AIService {
    constructor() {
        // إعدادات Hugging Face API
        this.hfApiKey = process.env.HF_API_KEY;
        
        // نماذج متعددة
        this.models = {
            // نموذج سريع للمهام البسيطة (توليد Shortcodes، اقتراحات سريعة)
            fast: process.env.AI_MODEL_FAST || 'Qwen/Qwen2.5-7B-Instruct',
            // نموذج دقيق للمهام المعقدة (توليد قوالب كاملة، تصاميم)
            precise: process.env.AI_MODEL_PRECISE || 'deepseek-ai/DeepSeek-R1',
            // نموذج احتياطي
            fallback: 'Qwen/Qwen2.5-7B-Instruct'
        };
        
        // عنوان API
        this.apiUrl = 'https://router.huggingface.co/v1/chat/completions';
        
        // تخزين مؤقت للنتائج
        this.cache = new Map();
        this.cacheTTL = 3600000; // ساعة واحدة
        
        // إحصائيات استخدام النماذج
        this.modelStats = {
            fast: { calls: 0, avgTime: 0 },
            precise: { calls: 0, avgTime: 0 }
        };
        
        console.log(`🤖 AI Service initialized with models:
  - Fast Model: ${this.models.fast}
  - Precise Model: ${this.models.precise}`);
    }
    
    /**
     * اختيار النموذج المناسب للمهمة
     */
selectModel(taskType) {
    // ✅ دائماً استخدم النموذج السريع (Qwen) لكل شيء أولاً
    // DeepSeek سيُستخدم فقط كاحتياطي إذا فشل Qwen
    return this.models.fast;  // Qwen/Qwen2.5-7B-Instruct
}
    
    /**
     * الحصول على مفتاح التخزين المؤقت
     */
    getCacheKey(prompt, type, model) {
        return crypto.createHash('md5').update(`${type}:${prompt}:${model}`).digest('hex');
    }
    
    /**
     * استدعاء Hugging Face API مع نموذج محدد
     */
    async callHuggingFace(prompt, temperature = 0.7, model = null) {
        if (!this.hfApiKey) {
            console.warn('⚠️ HF_API_KEY not configured, using fallback responses');
            return null;
        }
        
        const selectedModel = model || this.models.fast;
        const startTime = Date.now();
        
        try {
            const response = await axios.post(
                this.apiUrl,
                {
                    model: selectedModel,
                    messages: [
                        {
                            role: 'system',
                            content: `You are an expert e-commerce and web design assistant for MGZon platform.
                            
Platform capabilities:
- Products: digital, projects, services
- Pages: custom pages with HTML/CSS/JS
- Shortcodes: products, product, contact-form, store-info, categories, testimonials, social-links
- Themes: custom colors, fonts, layouts, full templates
- Store sections: hero, featured, products, categories, testimonials, faq, contact, html, products_grid

Respond with valid JSON when requested. Be concise, professional, and ensure output matches MGZon format.`
                        },
                        {
                            role: 'user',
                            content: prompt
                        }
                    ],
                    temperature: temperature,
                    max_tokens: 4096,
                    top_p: 0.95
                },
                {
                    headers: {
                        'Authorization': `Bearer ${this.hfApiKey}`,
                        'Content-Type': 'application/json'
                    },
                    timeout: 30000 // 90 seconds timeout for complex tasks
                }
            );
            
            const content = response.data?.choices?.[0]?.message?.content;
            if (!content) {
                throw new Error('Empty response from Hugging Face');
            }
            
            // تحديث الإحصائيات
            const modelType = selectedModel === this.models.precise ? 'precise' : 'fast';
            const timeTaken = Date.now() - startTime;
            this.modelStats[modelType].calls++;
            this.modelStats[modelType].avgTime = 
                (this.modelStats[modelType].avgTime * (this.modelStats[modelType].calls - 1) + timeTaken) / 
                this.modelStats[modelType].calls;
            
            return content;
            
        } catch (error) {
            console.error(`Hugging Face API error (${selectedModel}):`, error.response?.data || error.message);
            return null;
        }
    }
    
    /**
     * استدعاء AI مع اختيار ذكي للنموذج
     */
    async callAI(prompt, temperature = 0.7, taskType = 'general') {
        // ✅ استخدم النموذج السريع (Qwen) أولاً
        const primaryModel = this.models.fast;  // Qwen
        const cacheKey = this.getCacheKey(prompt, taskType, primaryModel);
        const cached = this.cache.get(cacheKey);
        
        if (cached && (Date.now() - cached.timestamp) < this.cacheTTL) {
            return cached.result;
        }
        
        console.log(`🤖 Trying primary model: ${primaryModel}`);
        let result = await this.callHuggingFace(prompt, temperature, primaryModel);
        
        // ✅ فقط إذا فشل Qwen، جرب DeepSeek كاحتياطي
        if (!result) {
            const fallbackModel = this.models.precise;  // DeepSeek
            console.log(`⚠️ Primary model failed, trying fallback: ${fallbackModel}`);
            result = await this.callHuggingFace(prompt, temperature, fallbackModel);
        }
        
        // ✅ إذا فشل كلاهما، استخدم الاحتياطي النهائي
        if (!result) {
            console.log(`⚠️ Both models failed, using final fallback: ${this.models.fallback}`);
            result = await this.callHuggingFace(prompt, temperature, this.models.fallback);
        }
        
        if (result) {
            this.cache.set(cacheKey, { result, timestamp: Date.now() });
            return result;
        }
        
        return null;
    }
    
    /**
     * توليد تخطيط صفحة كامل - محسن مع دعم القوالب
     */
    async generatePageLayout(description, storeType = 'general') {
        const prompt = `
You are an expert e-commerce web designer for MGZon platform. Generate a complete store page layout.

User description: "${description}"
Store type: ${storeType}

Available section types: hero, products, featured, categories, testimonials, faq, contact, html, products_grid

Generate a JSON object with this exact structure:
{
    "name": "Suggested page name (max 50 chars)",
    "sections": [
        {
            "type": "section_type",
            "title": "Section title (if applicable)",
            "order": 1,
            "enabled": true,
            "limit": 6,
            "layout": "grid",
            "columns": 4,
            "content": {}
        }
    ],
    "theme": {
        "primaryColor": "#hex",
        "secondaryColor": "#hex",
        "accentColor": "#hex",
        "fontFamily": "Inter, sans-serif",
        "layout": "full-width",
        "backgroundType": "default",
        "borderRadius": 16,
        "animationType": "lift"
    },
    "seo": {
        "title": "Suggested SEO title (50-60 chars)",
        "description": "Suggested meta description (150-160 chars)",
        "keywords": ["keyword1", "keyword2", "keyword3"]
    }
}

Return ONLY valid JSON, no explanation. Ensure all colors are valid hex codes.
`;
        
        try {
            const response = await this.callAI(prompt, 0.8, 'layout');
            
            if (!response) {
                return this.getFallbackLayout(description, storeType);
            }
            
            const cleanResponse = response
                .replace(/```json\n?/g, '')
                .replace(/```\n?/g, '')
                .replace(/`/g, '')
                .trim();
            
            const layout = JSON.parse(cleanResponse);
            
            // التحقق من صحة البيانات
            layout.sections = layout.sections.map((s, i) => ({
                ...s,
                order: s.order || i + 1,
                enabled: s.enabled !== false
            }));
            
            return {
                success: true,
                layout: layout,
                modelUsed: this.modelStats.fast.calls > this.modelStats.precise.calls ? this.models.fast : this.models.precise,
                modelStats: this.modelStats
            };
        } catch (error) {
            console.error('AI layout generation error:', error);
            return {
                success: false,
                error: error.message,
                fallback: this.getFallbackLayout(description, storeType)
            };
        }
    }
    
    /**
     * قوالب احتياطية محسّنة ومتوافقة مع النظام
     */
    getFallbackLayout(description, storeType) {
        const layouts = {
            fashion: {
                name: 'Fashion Store',
                sections: [
                    { type: 'hero', order: 1, enabled: true, content: { title: 'New Collection', subtitle: 'Discover the latest trends', buttonText: 'Shop Now', buttonLink: '#products' } },
                    { type: 'featured', order: 2, enabled: true, title: 'Featured Products', limit: 6, layout: 'grid' },
                    { type: 'categories', order: 3, enabled: true, title: 'Shop by Category', layout: 'grid' },
                    { type: 'products', order: 4, enabled: true, title: 'All Products', limit: 12, layout: 'grid', columns: 4 },
                    { type: 'testimonials', order: 5, enabled: true, title: 'What Our Customers Say', limit: 4 },
                    { type: 'contact', order: 6, enabled: true, title: 'Get in Touch' }
                ],
                theme: {
                    primaryColor: '#ec4899',
                    secondaryColor: '#8b5cf6',
                    accentColor: '#f43f5e',
                    fontFamily: 'Poppins, sans-serif',
                    layout: 'full-width',
                    backgroundType: 'gradient',
                    backgroundValue: 'linear-gradient(135deg, #fdf2f8 0%, #fce7f3 100%)',
                    borderRadius: 20,
                    animationType: 'lift'
                },
                seo: {
                    title: 'Fashion Store | Latest Trends & Styles',
                    description: 'Discover the latest fashion trends. Shop our collection of clothing, accessories, and more. Free shipping on orders over $50.',
                    keywords: ['fashion', 'clothing', 'trends', 'style', 'shop', 'online store']
                }
            },
            electronics: {
                name: 'Tech Store',
                sections: [
                    { type: 'hero', order: 1, enabled: true, content: { title: 'Latest Technology', subtitle: 'Cutting-edge gadgets at best prices', buttonText: 'Shop Now', buttonLink: '#products' } },
                    { type: 'categories', order: 2, enabled: true, title: 'Shop by Category', layout: 'grid' },
                    { type: 'featured', order: 3, enabled: true, title: 'Best Sellers', limit: 6, sort: 'popular' },
                    { type: 'products', order: 4, enabled: true, title: 'All Products', limit: 12, layout: 'grid', columns: 4 },
                    { type: 'faq', order: 5, enabled: true, title: 'Frequently Asked Questions' },
                    { type: 'contact', order: 6, enabled: true, title: 'Support' }
                ],
                theme: {
                    primaryColor: '#06b6d4',
                    secondaryColor: '#3b82f6',
                    accentColor: '#10b981',
                    fontFamily: 'Inter, sans-serif',
                    layout: 'full-width',
                    backgroundType: 'grid',
                    borderRadius: 12,
                    animationType: 'scale'
                },
                seo: {
                    title: 'Tech Store | Electronics & Gadgets',
                    description: 'Shop the latest electronics, gadgets, and tech accessories. Best prices and fast shipping. 30-day return policy.',
                    keywords: ['electronics', 'gadgets', 'technology', 'tech', 'shop', 'online store']
                }
            },
            food: {
                name: 'Food & Restaurant',
                sections: [
                    { type: 'hero', order: 1, enabled: true, content: { title: 'Delicious Food', subtitle: 'Order online for delivery', buttonText: 'Order Now', buttonLink: '#products' } },
                    { type: 'featured', order: 2, enabled: true, title: 'Popular Dishes', limit: 6, type: 'service' },
                    { type: 'categories', order: 3, enabled: true, title: 'Menu Categories', layout: 'grid' },
                    { type: 'products', order: 4, enabled: true, title: 'Full Menu', limit: 12, layout: 'grid', columns: 3, type: 'service' },
                    { type: 'testimonials', order: 5, enabled: true, title: 'Customer Reviews', limit: 3 },
                    { type: 'contact', order: 6, enabled: true, title: 'Contact Us' }
                ],
                theme: {
                    primaryColor: '#f59e0b',
                    secondaryColor: '#ef4444',
                    accentColor: '#22c55e',
                    fontFamily: 'Playfair Display, serif',
                    layout: 'full-width',
                    backgroundType: 'dots',
                    borderRadius: 24,
                    animationType: 'lift'
                },
                seo: {
                    title: 'Food & Restaurant | Order Online',
                    description: 'Delicious food delivered to your door. Browse our menu and order online for fast delivery. Fresh ingredients, great taste.',
                    keywords: ['food', 'restaurant', 'delivery', 'order online', 'menu', 'catering']
                }
            },
            art: {
                name: 'Art Gallery',
                sections: [
                    { type: 'hero', order: 1, enabled: true, content: { title: 'Art Gallery', subtitle: 'Discover unique artworks', buttonText: 'Browse Art', buttonLink: '#products' } },
                    { type: 'featured', order: 2, enabled: true, title: 'Featured Artworks', limit: 6 },
                    { type: 'categories', order: 3, enabled: true, title: 'Categories', layout: 'grid' },
                    { type: 'products', order: 4, enabled: true, title: 'All Artworks', limit: 12, layout: 'masonry', columns: 3 },
                    { type: 'testimonials', order: 5, enabled: true, title: 'Collector Reviews', limit: 4 }
                ],
                theme: {
                    primaryColor: '#a855f7',
                    secondaryColor: '#ec4899',
                    accentColor: '#06b6d4',
                    fontFamily: 'Poppins, sans-serif',
                    layout: 'boxed',
                    backgroundType: 'cross',
                    borderRadius: 16,
                    animationType: 'glow'
                },
                seo: {
                    title: 'Art Gallery | Original Artworks',
                    description: 'Discover unique original artworks from talented artists. Paintings, sculptures, digital art. Worldwide shipping.',
                    keywords: ['art', 'gallery', 'artwork', 'painting', 'sculpture', 'artist']
                }
            },
            general: {
                name: 'My Store',
                sections: [
                    { type: 'hero', order: 1, enabled: true, content: { title: 'Welcome to My Store', subtitle: 'Quality products at great prices', buttonText: 'Shop Now', buttonLink: '#products' } },
                    { type: 'featured', order: 2, enabled: true, title: 'Featured Products', limit: 6 },
                    { type: 'categories', order: 3, enabled: true, title: 'Categories', layout: 'grid' },
                    { type: 'products', order: 4, enabled: true, title: 'All Products', limit: 12, layout: 'grid', columns: 4 },
                    { type: 'testimonials', order: 5, enabled: true, title: 'What Our Customers Say', limit: 3 },
                    { type: 'faq', order: 6, enabled: true, title: 'Frequently Asked Questions' },
                    { type: 'contact', order: 7, enabled: true, title: 'Contact Us' }
                ],
                theme: {
                    primaryColor: '#3b82f6',
                    secondaryColor: '#8b5cf6',
                    accentColor: '#f59e0b',
                    fontFamily: 'Inter, sans-serif',
                    layout: 'full-width',
                    backgroundType: 'default',
                    borderRadius: 16,
                    animationType: 'lift'
                },
                seo: {
                    title: 'My Store | Quality Products',
                    description: 'Shop our collection of quality products. Best prices, fast shipping, and excellent customer service.',
                    keywords: ['store', 'shop', 'products', 'online store', 'ecommerce']
                }
            }
        };
        
        return {
            success: false,
            fallback: true,
            layout: layouts[storeType] || layouts.general,
            message: 'Using fallback layout (AI service unavailable)'
        };
    }
    
    /**
     * توليد قالب كامل للمتجر
     */
    async generateCompleteTemplate(description, style = 'modern') {
        const prompt = `
Generate a complete store template for MGZon platform.

Description: "${description}"
Style preference: ${style} (modern/minimal/elegant/bold)

Return a JSON object with:
{
    "name": "Template name",
    "description": "Template description",
    "category": "fashion|electronics|food|art|general",
    "sections": [array of sections],
    "theme": { theme settings },
    "seo": { seo settings },
    "shortcodes": ["[products limit=\"6\"]", "[contact-form]"]
}

Ensure the template is fully compatible with MGZon platform's store system.
Return ONLY valid JSON.
`;
        
        try {
            const response = await this.callAI(prompt, 0.85, 'template');
            
            if (!response) {
                return this.getFallbackTemplate(description, style);
            }
            
            const cleanResponse = response
                .replace(/```json\n?/g, '')
                .replace(/```\n?/g, '')
                .replace(/`/g, '')
                .trim();
            
            const template = JSON.parse(cleanResponse);
            
            return {
                success: true,
                template: template,
                modelUsed: this.models.precise,
                modelStats: this.modelStats
            };
        } catch (error) {
            console.error('AI template generation error:', error);
            return this.getFallbackTemplate(description, style);
        }
    }
    
    getFallbackTemplate(description, style) {
        return {
            success: false,
            fallback: true,
            template: {
                name: `${style.charAt(0).toUpperCase() + style.slice(1)} Store`,
                description: description || `A beautiful ${style} store template`,
                category: 'general',
                sections: [
                    { type: 'hero', order: 1, content: { title: 'Welcome', buttonText: 'Shop Now' } },
                    { type: 'products', order: 2, title: 'Products', limit: 12 }
                ],
                theme: {
                    primaryColor: '#3b82f6',
                    secondaryColor: '#8b5cf6',
                    fontFamily: 'Inter, sans-serif'
                },
                shortcodes: ['[products limit="6"]', '[contact-form]']
            },
            message: 'Using fallback template (AI service unavailable)'
        };
    }
    
    /**
     * باقي الدوال (generateShortcode, suggestDesign, enhanceProductDescription, etc.)
     * تبقى كما هي مع إضافة modelStats
     */
    
    async generateShortcode(description) {
        const prompt = `
Based on this description: "${description}"

Generate an appropriate shortcode from these available shortcodes:
- [products] - products grid (parameters: limit, type, layout, sort, columns, category)
- [product] - single product (parameters: id, layout)
- [contact-form] - contact form (parameters: title, fields)
- [testimonials] - customer reviews (parameters: limit, autoplay)
- [categories] - categories (parameters: layout, showCount)
- [search-form] - search box (parameters: placeholder, showFilters)
- [store-info] - store info (parameters: field)
- [cart-count] - cart count
- [social-links] - social links (parameters: layout)

Return ONLY the shortcode, no explanation.
Example: [products limit="6" type="digital" layout="grid" sort="popular"]
`;
        
        try {
            const response = await this.callAI(prompt, 0.5, 'shortcode');
            
            if (!response) {
                return {
                    success: false,
                    fallback: '[products limit="6"]',
                    message: 'AI service unavailable, using fallback'
                };
            }
            
            const cleanShortcode = response
                .trim()
                .replace(/`/g, '')
                .replace(/^\[/, '[')
                .replace(/\]$/, ']');
            
            return {
                success: true,
                shortcode: cleanShortcode,
                modelUsed: this.modelStats.fast.calls > this.modelStats.precise.calls ? this.models.fast : this.models.precise,
                modelStats: this.modelStats
            };
        } catch (error) {
            return {
                success: false,
                error: error.message,
                fallback: '[products limit="6"]'
            };
        }
    }
    
    suggestDesign(storeType) {
        const suggestions = {
            fashion: {
                primaryColor: '#ec4899',
                secondaryColor: '#8b5cf6',
                accentColor: '#f43f5e',
                fontFamily: 'Poppins, sans-serif',
                headingFont: 'Poppins, sans-serif',
                backgroundType: 'gradient',
                backgroundValue: 'linear-gradient(135deg, #fdf2f8 0%, #fce7f3 100%)',
                borderRadius: 20,
                animationType: 'lift'
            },
            electronics: {
                primaryColor: '#06b6d4',
                secondaryColor: '#3b82f6',
                accentColor: '#10b981',
                fontFamily: 'Inter, sans-serif',
                headingFont: 'Inter, sans-serif',
                backgroundType: 'grid',
                borderRadius: 12,
                animationType: 'scale'
            },
            food: {
                primaryColor: '#f59e0b',
                secondaryColor: '#ef4444',
                accentColor: '#22c55e',
                fontFamily: 'Playfair Display, serif',
                headingFont: 'Playfair Display, serif',
                backgroundType: 'dots',
                borderRadius: 24,
                animationType: 'lift'
            },
            art: {
                primaryColor: '#a855f7',
                secondaryColor: '#ec4899',
                accentColor: '#06b6d4',
                fontFamily: 'Poppins, sans-serif',
                headingFont: 'Poppins, sans-serif',
                backgroundType: 'cross',
                borderRadius: 16,
                animationType: 'glow'
            },
            general: {
                primaryColor: '#3b82f6',
                secondaryColor: '#8b5cf6',
                accentColor: '#f59e0b',
                fontFamily: 'Inter, sans-serif',
                headingFont: 'Inter, sans-serif',
                backgroundType: 'default',
                borderRadius: 16,
                animationType: 'lift'
            }
        };
        
        return suggestions[storeType] || suggestions.general;
    }
    
    async enhanceProductDescription(title, currentDescription, tags = []) {
        const prompt = `
Improve this product description:

Title: ${title}
Current: ${currentDescription || 'No description'}
Tags: ${tags.join(', ')}

Write an engaging, SEO-friendly description (150-200 words) with benefits, keywords, and call to action.
Return ONLY the description, no explanation.
`;
        
        try {
            const response = await this.callAI(prompt, 0.7, 'description_enhance');
            
            if (!response) {
                return {
                    success: false,
                    description: currentDescription || `${title} - High quality product. Shop now!`
                };
            }
            
            return {
                success: true,
                description: response.trim(),
                modelUsed: this.modelStats.fast.calls > this.modelStats.precise.calls ? this.models.fast : this.models.precise
            };
        } catch (error) {
            return {
                success: false,
                description: currentDescription,
                error: error.message
            };
        }
    }
    
    async suggestKeywords(title, category, storeType) {
        const prompt = `
Suggest 10 SEO keywords for:
Title: ${title}
Category: ${category}
Store Type: ${storeType}

Return ONLY comma-separated keywords, no explanation.
`;
        
        try {
            const response = await this.callAI(prompt, 0.3, 'keyword');
            
            if (!response) {
                return {
                    success: false,
                    keywords: [title, category, storeType, 'online store', 'buy online']
                };
            }
            
            const keywords = response
                .trim()
                .split(',')
                .map(k => k.trim())
                .filter(k => k.length > 0);
            
            return {
                success: true,
                keywords: keywords.slice(0, 10),
                modelUsed: this.modelStats.fast.calls > this.modelStats.precise.calls ? this.models.fast : this.models.precise
            };
        } catch (error) {
            return {
                success: false,
                keywords: [title, category, storeType, 'online store', 'buy online']
            };
        }
    }
    
    async generateStoreDescription(storeName, industry, products) {
        const prompt = `
Write a store description for:
Store Name: ${storeName}
Industry: ${industry}
Products: ${products.join(', ')}

Write 100-150 words, welcoming, unique, with call to action.
Return ONLY the description.
`;
        
        try {
            const response = await this.callAI(prompt, 0.6, 'general');
            
            if (!response) {
                return {
                    success: false,
                    description: `Welcome to ${storeName}! We offer high-quality ${industry} products. Shop now!`
                };
            }
            
            return {
                success: true,
                description: response.trim(),
                modelUsed: this.modelStats.fast.calls > this.modelStats.precise.calls ? this.models.fast : this.models.precise
            };
        } catch (error) {
            return {
                success: false,
                description: `Welcome to ${storeName}! We offer high-quality ${industry} products. Shop now!`
            };
        }
    }
    
    clearCache() {
        this.cache.clear();
        console.log('🗑️ AI cache cleared');
        console.log('📊 Model stats:', this.modelStats);
    }
    
    async testConnection() {
        try {
            const testPrompt = "Say 'API works' and nothing else.";
            const response = await this.callHuggingFace(testPrompt, 0.1, this.models.fast);
            
            if (response && response.includes('API works')) {
                console.log('✅ Hugging Face API connection successful');
                return true;
            }
            console.log('⚠️ Hugging Face API test failed');
            return false;
        } catch (error) {
            console.error('❌ Hugging Face API connection failed:', error.message);
            return false;
        }
    }
}

module.exports = new AIService();