nordabiz/email_service.py

"""
Norda Biznes - Email Service
=============================

Sends emails via Microsoft Graph API using Application permissions.
Based on mtbtracker implementation.

Author: Norda Biznes Development Team
Created: 2025-12-25
"""

import os
import logging
from typing import Optional, List
from dotenv import load_dotenv

# Load .env file for environment variables
load_dotenv()

logger = logging.getLogger(__name__)

# Check if msal is available
try:
    import msal
    import requests
    MSAL_AVAILABLE = True
except ImportError:
    MSAL_AVAILABLE = False
    logger.warning("msal package not installed. Email service will be disabled.")


class EmailService:
    """Service for sending emails via Microsoft Graph API"""

    def __init__(self, tenant_id: str, client_id: str, client_secret: str, mail_from: str):
        """
        Initialize Email Service

        Args:
            tenant_id: Azure AD Tenant ID
            client_id: Application (client) ID
            client_secret: Client secret value
            mail_from: Default sender email address (e.g., noreply@inpi.pl)
        """
        self.tenant_id = tenant_id
        self.client_id = client_id
        self.client_secret = client_secret
        self.mail_from = mail_from
        self.authority = f"https://login.microsoftonline.com/{tenant_id}"
        self.scope = ["https://graph.microsoft.com/.default"]
        self.graph_endpoint = "https://graph.microsoft.com/v1.0"

    def _get_access_token(self) -> Optional[str]:
        """
        Acquire access token using client credentials flow

        Returns:
            Access token string or None if failed
        """
        if not MSAL_AVAILABLE:
            logger.error("msal package not available")
            return None

        try:
            app = msal.ConfidentialClientApplication(
                self.client_id,
                authority=self.authority,
                client_credential=self.client_secret,
            )

            result = app.acquire_token_silent(self.scope, account=None)

            if not result:
                logger.info("No token in cache, acquiring new token")
                result = app.acquire_token_for_client(scopes=self.scope)

            if "access_token" in result:
                return result["access_token"]
            else:
                logger.error(f"Failed to acquire token: {result.get('error')}: {result.get('error_description')}")
                return None

        except Exception as e:
            logger.error(f"Exception during token acquisition: {e}", exc_info=True)
            return None

    def send_mail(
        self,
        to: List[str],
        subject: str,
        body_text: str,
        body_html: Optional[str] = None,
        from_address: Optional[str] = None,
        bcc: Optional[List[str]] = None
    ) -> bool:
        """
        Send email via Microsoft Graph API

        Args:
            to: List of recipient email addresses
            subject: Email subject
            body_text: Plain text email body
            body_html: HTML email body (optional)
            from_address: Sender email (optional, defaults to configured mail_from)
            bcc: List of BCC recipient email addresses (optional)

        Returns:
            True if sent successfully, False otherwise
        """
        if not MSAL_AVAILABLE:
            logger.error("msal package not available - cannot send email")
            return False

        try:
            # Get access token
            token = self._get_access_token()
            if not token:
                logger.error("Failed to acquire access token")
                return False

            # Use default sender if not specified
            sender = from_address or self.mail_from

            # Prepare recipients
            recipients = [{"emailAddress": {"address": email}} for email in to]

            # Prepare message body
            if body_html:
                content_type = "HTML"
                content = body_html
            else:
                content_type = "Text"
                content = body_text

            # Build email message
            # Display name for sender - shown in email clients
            sender_display_name = "Norda Biznes Partner"

            email_msg = {
                "message": {
                    "subject": subject,
                    "body": {
                        "contentType": content_type,
                        "content": content
                    },
                    "toRecipients": recipients,
                    "from": {
                        "emailAddress": {
                            "address": sender,
                            "name": sender_display_name
                        }
                    }
                },
                "saveToSentItems": "false"
            }

            # Add BCC recipients if provided
            if bcc:
                bcc_recipients = [{"emailAddress": {"address": email}} for email in bcc]
                email_msg["message"]["bccRecipients"] = bcc_recipients

            # Send email via Graph API
            url = f"{self.graph_endpoint}/users/{sender}/sendMail"
            headers = {
                "Authorization": f"Bearer {token}",
                "Content-Type": "application/json"
            }

            response = requests.post(url, headers=headers, json=email_msg, timeout=30)

            if response.status_code == 202:
                logger.info(f"Email sent successfully to {to}")
                return True
            else:
                logger.error(f"Failed to send email. Status: {response.status_code}, Response: {response.text}")
                return False

        except Exception as e:
            logger.error(f"Exception during email sending: {e}", exc_info=True)
            return False


# Global service instance
_email_service: Optional[EmailService] = None


def init_email_service():
    """
    Initialize the global Email Service instance from environment variables

    Required env vars:
        AZURE_TENANT_ID: Azure AD Tenant ID
        AZURE_CLIENT_ID: Application (client) ID
        AZURE_CLIENT_SECRET: Client secret value
        MAIL_FROM: Default sender email address
    """
    global _email_service

    tenant_id = os.getenv('AZURE_TENANT_ID')
    client_id = os.getenv('AZURE_CLIENT_ID')
    client_secret = os.getenv('AZURE_CLIENT_SECRET')
    mail_from = os.getenv('MAIL_FROM', 'noreply@inpi.pl')

    if tenant_id and client_id and client_secret:
        _email_service = EmailService(tenant_id, client_id, client_secret, mail_from)
        logger.info(f"Email Service initialized with sender: {mail_from}")
        return True
    else:
        logger.warning("Email Service not configured - missing Azure credentials")
        return False


def send_email(
    to: List[str],
    subject: str,
    body_text: str,
    body_html: Optional[str] = None,
    from_address: Optional[str] = None,
    email_type: str = 'notification',
    user_id: Optional[int] = None,
    recipient_name: Optional[str] = None,
    bcc: Optional[List[str]] = None
) -> bool:
    """
    Send email using the global Email Service instance

    Args:
        to: List of recipient email addresses (can be single email as list)
        subject: Email subject
        body_text: Plain text email body
        body_html: HTML email body (optional)
        from_address: Sender email (optional)
        email_type: Type of email for logging (welcome, password_reset, notification)
        user_id: User ID for logging (optional)
        recipient_name: Recipient name for logging (optional)
        bcc: List of BCC emails (optional, defaults to MAIL_BCC env var)

    Returns:
        True if sent successfully, False otherwise
    """
    if not _email_service:
        logger.error("Email Service not initialized. Call init_email_service() first.")
        return False

    # Convert single email to list if needed
    if isinstance(to, str):
        to = [to]

    # Default BCC from env var — admin gets a copy of every email
    if bcc is None:
        default_bcc = os.getenv('MAIL_BCC', 'maciej.pienczyn@inpi.pl')
        if default_bcc:
            bcc = [addr.strip() for addr in default_bcc.split(',') if addr.strip()]
            # Don't BCC someone who is already a direct recipient
            bcc = [addr for addr in bcc if addr not in to]

    result = _email_service.send_mail(to, subject, body_text, body_html, from_address, bcc=bcc)

    # Log email to database
    _log_email(
        email_type=email_type,
        recipient_emails=to,
        recipient_name=recipient_name,
        subject=subject,
        user_id=user_id,
        sender_email=from_address or _email_service.mail_from if _email_service else None,
        success=result
    )

    return result


def _log_email(
    email_type: str,
    recipient_emails: List[str],
    subject: str,
    success: bool,
    recipient_name: Optional[str] = None,
    user_id: Optional[int] = None,
    sender_email: Optional[str] = None,
    error_message: Optional[str] = None
) -> None:
    """
    Log email to database for monitoring.

    Args:
        email_type: Type of email (welcome, password_reset, notification)
        recipient_emails: List of recipient email addresses
        subject: Email subject
        success: Whether email was sent successfully
        recipient_name: Recipient name (optional)
        user_id: User ID (optional)
        sender_email: Sender email address (optional)
        error_message: Error message if failed (optional)
    """
    try:
        from database import SessionLocal, EmailLog
        from datetime import datetime

        db = SessionLocal()
        try:
            for email in recipient_emails:
                log_entry = EmailLog(
                    email_type=email_type,
                    recipient_email=email,
                    recipient_name=recipient_name,
                    subject=subject,
                    user_id=user_id,
                    sender_email=sender_email,
                    status='sent' if success else 'failed',
                    sent_at=datetime.utcnow() if success else None,
                    error_message=error_message if not success else None
                )
                db.add(log_entry)
            db.commit()
            logger.info(f"Email logged: {email_type} -> {recipient_emails} (status: {'sent' if success else 'failed'})")
        except Exception as e:
            db.rollback()
            logger.error(f"Failed to log email to database: {e}")
        finally:
            db.close()
    except ImportError:
        # Database not available (e.g., during testing)
        logger.warning("Could not log email - database module not available")


def is_configured() -> bool:
    """
    Check if Email Service is configured and ready

    Returns:
        True if service is initialized, False otherwise
    """
    return _email_service is not None


# Auto-initialize on module load
init_email_service()


# ============================================================
# EMAIL TEMPLATES (v3 design)
# ============================================================

def _email_v3_wrap(title: str, subtitle: str, content_html: str) -> str:
    """Wrap email content in v3 branded shell (header + footer)."""
    return f'''<!DOCTYPE html>
<html lang="pl">
<head><meta charset="UTF-8"></head>
<body style="margin:0; padding:0; background:#f1f5f9; font-family: 'Inter', Arial, sans-serif;">
<table width="100%" cellpadding="0" cellspacing="0" style="background:#f1f5f9; padding: 32px 0;">
<tr><td align="center">
<table width="600" cellpadding="0" cellspacing="0" style="background:#ffffff; border-radius:12px; overflow:hidden; box-shadow: 0 4px 24px rgba(0,0,0,0.08);">

<tr><td style="background: linear-gradient(135deg, #1e40af, #172554); padding: 36px 32px; text-align: center;">
    <img src="https://nordabiznes.pl/static/img/logo-email.png" width="64" height="64" alt="NB" style="border-radius:50%; margin-bottom:16px; border: 2px solid rgba(255,255,255,0.3);">
    <h1 style="margin:0; color:#ffffff; font-size:24px; font-weight:700;">{title}</h1>
    <p style="margin:8px 0 0; color:#93c5fd; font-size:14px;">{subtitle}</p>
</td></tr>

<tr><td style="padding: 32px;">
{content_html}
</td></tr>

<tr><td style="background:#f8fafc; padding: 24px; text-align:center; border-top: 1px solid #e2e8f0;">
    <p style="margin:0 0 4px; color:#1e293b; font-size:14px; font-weight:600;">Norda Biznes Partner</p>
    <p style="margin:0 0 2px; color:#94a3b8; font-size:12px;">Stowarzyszenie Norda Biznes</p>
    <p style="margin:0 0 12px; color:#94a3b8; font-size:12px;">ul. 12 Marca 238/5, 84-200 Wejherowo</p>
    <p style="margin:0 0 12px; color:#94a3b8; font-size:13px;">
        <a href="https://nordabiznes.pl" style="color:#2563eb; text-decoration:none;">nordabiznes.pl</a>
        &nbsp;|&nbsp;
        <a href="https://www.facebook.com/profile.php?id=100057396041901" style="color:#2563eb; text-decoration:none;">Facebook</a>
    </p>
    <p style="margin:0; color:#cbd5e1; font-size:11px;">To powiadomienie zostało wysłane automatycznie.</p>
</td></tr>

</table>
</td></tr>
</table>
</body>
</html>'''


def send_password_reset_email(email: str, reset_url: str) -> bool:
    """Send password reset email."""
    subject = "Reset hasła - Norda Biznes Partner"

    body_text = f"""Otrzymałeś ten email, ponieważ zażądano resetowania hasła dla Twojego konta Norda Biznes Partner.

Aby zresetować hasło, kliknij w poniższy link:
{reset_url}

Link będzie ważny przez 1 godzinę.

Jeśli nie zażądałeś resetowania hasła, zignoruj ten email.

---
Norda Biznes Partner
https://nordabiznes.pl
"""

    content = f'''
    <p style="margin:0 0 20px; color:#1e293b; font-size:16px;">Otrzymałeś ten email, ponieważ zażądano resetowania hasła dla Twojego konta.</p>

    <p style="margin:0 0 24px; color:#475569; font-size:15px;">Kliknij poniższy przycisk, aby ustawić nowe hasło:</p>

    <table width="100%" cellpadding="0" cellspacing="0" style="margin-bottom:24px;">
    <tr><td align="center" style="padding: 8px 0;">
        <a href="{reset_url}" style="display:inline-block; padding:16px 40px; background: linear-gradient(135deg, #dc2626, #991b1b); color:#ffffff; text-decoration:none; border-radius:8px; font-size:15px; font-weight:600;">Zresetuj hasło</a>
    </td></tr>
    </table>

    <!-- Warning -->
    <table width="100%" cellpadding="0" cellspacing="0" style="background:#fef3c7; border-radius:8px; border: 1px solid #fcd34d; margin-bottom:24px;">
    <tr><td style="padding: 16px;">
        <p style="margin:0 0 4px; color:#92400e; font-size:14px; font-weight:600;">Ważność linku: 1 godzina</p>
        <p style="margin:0; color:#92400e; font-size:13px;">Po tym czasie konieczne będzie ponowne żądanie resetu hasła.</p>
    </td></tr>
    </table>

    <p style="margin:0 0 8px; color:#64748b; font-size:13px;">Jeśli przycisk nie działa, skopiuj i wklej ten link:</p>
    <p style="margin:0 0 24px; color:#2563eb; font-size:13px; word-break:break-all;">{reset_url}</p>

    <table width="100%" cellpadding="0" cellspacing="0" style="background:#f8fafc; border-radius:8px; border: 1px solid #e2e8f0;">
    <tr><td style="padding: 16px;">
        <p style="margin:0; color:#64748b; font-size:14px;">
            <strong>Nie zażądałeś resetowania hasła?</strong><br>
            Zignoruj ten email — Twoje hasło pozostanie bez zmian.
        </p>
    </td></tr>
    </table>'''

    body_html = _email_v3_wrap('Reset hasła', 'Norda Biznes Partner', content)

    return send_email(
        to=[email],
        subject=subject,
        body_text=body_text,
        body_html=body_html,
        email_type='password_reset'
    )


def send_welcome_email(email: str, name: str, verification_url: str) -> bool:
    """Send welcome/verification email after registration."""
    subject = "Witamy w Norda Biznes Partner — Potwierdź email"

    body_text = f"""Witaj {name}!

Dziękujemy za rejestrację w Norda Biznes Partner.

Aby aktywować konto, kliknij: {verification_url}
Link ważny 24 godziny.

Pozdrawiamy,
Zespół Norda Biznes Partner
https://nordabiznes.pl
"""

    check = (
        '<div style="width:28px; height:28px; background:#16a34a; border-radius:50%; '
        'text-align:center; line-height:28px; display:inline-block; margin-right:10px;">'
        '<span style="color:#fff; font-size:16px; font-weight:bold;">&#10003;</span></div>'
    )

    content = f'''
    <p style="margin:0 0 16px; color:#1e293b; font-size:16px;">Witaj <strong>{name}</strong>!</p>
    <p style="margin:0 0 28px; color:#475569; font-size:15px; line-height:1.5;">Dziękujemy za rejestrację w Norda Biznes Partner — platformie networkingu Regionalnej Izby Przedsiębiorców.</p>

    <p style="margin:0 0 16px; color:#1e293b; font-size:15px;">Aby aktywować konto, potwierdź swój adres email:</p>

    <table width="100%" cellpadding="0" cellspacing="0" style="margin-bottom:28px;">
    <tr><td align="center" style="padding: 8px 0;">
        <a href="{verification_url}" style="display:inline-block; padding:16px 40px; background: linear-gradient(135deg, #16a34a, #15803d); color:#ffffff; text-decoration:none; border-radius:8px; font-size:15px; font-weight:600;">Potwierdź email</a>
    </td></tr>
    </table>

    <p style="margin:0 0 14px; color:#1e293b; font-size:16px; font-weight:600;">Co zyskujesz:</p>
    <table width="100%" cellpadding="0" cellspacing="0" style="background:#f8fdf8; border-radius:10px; border: 1px solid #d1fae5; margin-bottom:28px;">
    <tr><td style="padding: 14px 16px; border-bottom: 1px solid #e2e8f0;">
        {check}<span style="color:#1e293b; font-size:15px; font-weight:500;">Katalog firm członkowskich Izby</span>
    </td></tr>
    <tr><td style="padding: 14px 16px; border-bottom: 1px solid #e2e8f0;">
        {check}<span style="color:#1e293b; font-size:15px; font-weight:500;">Asystent AI do wyszukiwania usług</span>
    </td></tr>
    <tr><td style="padding: 14px 16px;">
        {check}<span style="color:#1e293b; font-size:15px; font-weight:500;">Networking i kontakty biznesowe</span>
    </td></tr>
    </table>

    <table width="100%" cellpadding="0" cellspacing="0" style="background:#fef3c7; border-radius:8px; border: 1px solid #fcd34d;">
    <tr><td style="padding: 14px 16px;">
        <p style="margin:0; color:#92400e; font-size:13px;">Link aktywacyjny jest ważny przez <strong>24 godziny</strong>.</p>
    </td></tr>
    </table>'''

    body_html = _email_v3_wrap('Witamy!', 'Norda Biznes Partner', content)

    return send_email(
        to=[email],
        subject=subject,
        body_text=body_text,
        body_html=body_html,
        email_type='welcome',
        recipient_name=name
    )