import smtplib
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from datetime import datetime
from pathlib import Path
from jinja2 import Template
from config import Config
from database import subscribers_collection, articles_collection


def send_newsletter(max_articles=10):
    """Send newsletter to all subscribers with AI-summarized articles"""
    if not Config.EMAIL_USER or not Config.EMAIL_PASSWORD:
        print("Email credentials not configured")
        return
    
    # Get latest articles with AI summaries from database
    cursor = articles_collection.find(
        {'summary': {'$exists': True, '$ne': None}}
    ).sort('created_at', -1).limit(max_articles)
    
    articles = []
    for doc in cursor:
        articles.append({
            'title': doc.get('title', ''),
            'author': doc.get('author'),
            'link': doc.get('link', ''),
            'summary': doc.get('summary', ''),
            'source': doc.get('source', ''),
            'published_at': doc.get('published_at', '')
        })
    
    if not articles:
        print("No articles with summaries to send")
        return
    
    # Load email template
    template_path = Path(__file__).parent.parent / 'templates' / 'newsletter_template.html'
    with open(template_path, 'r', encoding='utf-8') as f:
        template_content = f.read()
    
    template = Template(template_content)
    
    # Prepare template data
    now = datetime.now()
    template_data = {
        'date': now.strftime('%A, %B %d, %Y'),
        'year': now.year,
        'article_count': len(articles),
        'articles': articles,
        'unsubscribe_link': 'http://localhost:3000',  # Update with actual unsubscribe link
        'website_link': 'http://localhost:3000'
    }
    
    # Render HTML
    html_content = template.render(**template_data)
    
    # Get all active subscribers
    subscribers_cursor = subscribers_collection.find({'status': 'active'})
    subscribers = [doc['email'] for doc in subscribers_cursor]
    
    # Send emails
    for subscriber in subscribers:
        try:
            msg = MIMEMultipart('alternative')
            msg['Subject'] = f'Munich News Daily - {datetime.now().strftime("%B %d, %Y")}'
            msg['From'] = f'Munich News Daily <{Config.EMAIL_USER}>'
            msg['To'] = subscriber
            msg['Date'] = datetime.now().strftime('%a, %d %b %Y %H:%M:%S %z')
            msg['Message-ID'] = f'<{datetime.now().timestamp()}.{subscriber}@dongho.kim>'
            msg['X-Mailer'] = 'Munich News Daily'
            
            # Add plain text version as fallback
            plain_text = "This email requires HTML support. Please view it in an HTML-capable email client."
            msg.attach(MIMEText(plain_text, 'plain', 'utf-8'))
            
            # Add HTML version
            msg.attach(MIMEText(html_content, 'html', 'utf-8'))
            
            server = smtplib.SMTP(Config.SMTP_SERVER, Config.SMTP_PORT)
            server.starttls()
            server.login(Config.EMAIL_USER, Config.EMAIL_PASSWORD)
            server.send_message(msg)
            server.quit()
            
            print(f"Newsletter sent to {subscriber}")
        except Exception as e:
            print(f"Error sending to {subscriber}: {e}")