app.py

# ============================================
# OMNIS AI Backend - Hugging Face Spaces
# ============================================

from flask import Flask, request, jsonify
from flask_cors import CORS
from gtts import gTTS
import io
import base64
import re
import random
from datetime import datetime
from collections import Counter

app = Flask(__name__)
CORS(app)

server_start_time = datetime.now()
total_requests = 0

STOPWORDS = {
    'il', 'lo', 'la', 'i', 'gli', 'le', 'un', 'una', 'uno', 'è', 'e', 'che', 'di',
    'a', 'da', 'in', 'con', 'su', 'per', 'tra', 'fra', 'non', 'si', 'come', 'più',
    'al', 'del', 'della', 'dei', 'delle', 'sono', 'ho', 'hai', 'ha', 'abbiamo',
    'hanno', 'era', 'erano', 'sarà', 'cui', 'dal', 'dalla', 'nel', 'nella',
    'questo', 'questa', 'molto', 'molta', 'molti', 'poco', 'the', 'and', 'for',
    'are', 'but', 'not', 'you', 'all', 'can', 'has', 'have', 'been', 'some'
}

def extract_keywords(text, top_n=6):
    words = re.findall(r'\b[a-zA-ZÀ-ÿ]{4,}\b', text.lower())
    filtered = [w for w in words if w not in STOPWORDS]
    return [w.capitalize() for w, _ in Counter(filtered).most_common(top_n)]

def extract_sentences(text, min_len=20):
    return [s.strip() for s in re.split(r'[.!?]+', text) if len(s.strip()) > min_len]

def generate_mermaid_code(text, keywords, sentences):
    main = keywords[0] if keywords else "Argomento"
    subs = keywords[1:5] if len(keywords) > 1 else ["Dettaglio"]
    
    mermaid = "graph TD\n"
    mermaid += f'    A["{main[:30]}"]\n'
    
    colors = ['#8B5CF6', '#06B6D4', '#10B981', '#F59E0B']
    
    for i, sub in enumerate(subs):
        node_id = chr(66 + i)
        sub_clean = sub[:30].replace('"', "'")
        mermaid += f'    {node_id}["{sub_clean}"]\n'
        mermaid += f'    A --> {node_id}\n'
        
        if i < len(sentences):
            detail = sentences[i][:50].replace('"', "'").strip()
            detail_id = f"{node_id}1"
            mermaid += f'    {detail_id}["{detail}..."]\n'
            mermaid += f'    {node_id} --> {detail_id}\n'
    
    mermaid += f'    style A fill:#1a1a2e,stroke:#8B5CF6,stroke-width:3px,color:#fff\n'
    for i in range(len(subs)):
        node_id = chr(66 + i)
        color = colors[i % len(colors)]
        mermaid += f'    style {node_id} fill:#1a1a2e,stroke:{color},stroke-width:2px,color:#fff\n'
    
    return mermaid

# ============================================
# HEALTH
# ============================================
@app.route('/api/health', methods=['GET'])
def health():
    return jsonify({
        'status': 'online',
        'uptime': str(datetime.now() - server_start_time).split('.')[0],
        'total_requests': total_requests,
        'host': 'huggingface',
        'online_24_7': True
    })

# ============================================
# GENERATE (Riassunto + Quiz)
# ============================================
@app.route('/api/generate', methods=['POST'])
def generate():
    global total_requests
    total_requests += 1
    
    try:
        service = request.form.get('service', 'summary')
        text_input = request.form.get('text_input', '')
        custom_prompt = request.form.get('custom_prompt', '')
        link = request.form.get('link', '')
        
        all_text = text_input[:3000] if text_input else ""
        
        if link:
            try:
                import requests as req
                from bs4 import BeautifulSoup
                resp = req.get(link, timeout=8, headers={'User-Agent': 'OMNIS/1.0'})
                soup = BeautifulSoup(resp.text, 'html.parser')
                for tag in soup(['script', 'style']):
                    tag.decompose()
                all_text += "\n" + soup.get_text(separator=' ', strip=True)[:2000]
            except:
                all_text += f"\n[Link: {link}]"
        
        if not all_text.strip():
            return jsonify({'success': False, 'error': 'Nessun testo fornito'}), 400
        
        sentences = extract_sentences(all_text)
        keywords = extract_keywords(all_text)
        
        if service == 'summary':
            result = f"📚 RIASSUNTO\n\n🔑 Concetti: {', '.join(keywords[:6])}\n\n"
            for i, s in enumerate(sentences[:10]):
                result += f"{i+1}. {s.strip()}.\n"
            result += f"\n📊 {len(all_text.split())} parole"
        elif service == 'quiz':
            if len(sentences) < 2:
                result = "Testo troppo corto per un quiz."
            else:
                result = "❓ QUIZ\n\n"
                for i, s in enumerate(sentences[:5]):
                    correct = chr(65 + random.randint(0, 3))
                    result += f"DOMANDA {i+1}: {' '.join(s.split()[:5])}...\n\n"
                    for opt in ['A', 'B', 'C', 'D']:
                        result += f"{opt}) {'✓' if opt == correct else ''} {s[:60] if opt == correct else sentences[(i+1)%len(sentences)][:60]}...\n"
                    result += f"\n✓ Risposta: {correct}\n\n"
        else:
            result = f"📚 RIASSUNTO\n\n" + '\n'.join(sentences[:10])
        
        return jsonify({'success': True, 'content': result, 'service': service})
        
    except Exception as e:
        return jsonify({'success': False, 'error': str(e)}), 500

# ============================================
# MINDMAP (restituisce codice Mermaid)
# ============================================
@app.route('/api/mindmap-image', methods=['POST'])
def mindmap_image():
    global total_requests
    total_requests += 1
    
    try:
        text = request.form.get('text_input', '')
        if not text:
            return jsonify({'success': False, 'error': 'Nessun testo'}), 400
        
        text = text[:2000]
        keywords = extract_keywords(text, 6)
        sentences = extract_sentences(text, 6)
        
        if not keywords:
            return jsonify({'success': False, 'error': 'Testo insufficiente'}), 400
        
        mermaid_code = generate_mermaid_code(text, keywords, sentences)
        
        return jsonify({
            'success': True,
            'mermaid_code': mermaid_code,
            'format': 'mermaid'
        })
        
    except Exception as e:
        return jsonify({'success': False, 'error': str(e)}), 500

# ============================================
# TEXT TO SPEECH
# ============================================
@app.route('/api/text-to-speech', methods=['POST'])
def text_to_speech():
    try:
        text = request.form.get('text', '')[:3000]
        if not text:
            return jsonify({'success': False, 'error': 'Nessun testo'}), 400
        
        tts = gTTS(text=text, lang='it', slow=False)
        buf = io.BytesIO()
        tts.write_to_fp(buf)
        buf.seek(0)
        
        return jsonify({
            'success': True,
            'audio_base64': base64.b64encode(buf.read()).decode('utf-8'),
            'format': 'mp3'
        })
    except Exception as e:
        return jsonify({'success': False, 'error': str(e)}), 500

if __name__ == '__main__':
    print("🚀 OMNIS Backend - Hugging Face")
    app.run(host='0.0.0.0', port=7860)