#!/usr/bin/env python3
"""
Test script für Message-ID Extraktion - VERBESSERTE VERSION
Kann lokal ausgeführt werden ohne AWS-Verbindung
"""

import re
from email.parser import BytesParser
from email.policy import SMTP as SMTPPolicy

def log(message: str, level: str = 'INFO'):
    """Dummy log für Tests"""
    print(f"[{level}] {message}")

def extract_original_message_id(parsed):
    """
    Extrahiert Original SES Message-ID aus Email
    SES Format: 010f[hex32]-[hex8]-[hex4]-[hex4]-[hex4]-[hex12]-000000
    """
    import re
    
    # SES Message-ID Pattern (endet immer mit -000000)
    ses_pattern = re.compile(r'010f[0-9a-f]{12}-[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}-000000')
    
    # Die Message-ID der aktuellen Email (Bounce selbst) - diese wollen wir NICHT
    current_msg_id = (parsed.get('Message-ID') or '').strip()
    current_match = ses_pattern.search(current_msg_id)
    current_id = current_match.group(0) if current_match else None
    
    log(f"Current Message-ID: {current_id}", 'DEBUG')
    
    # 1. Versuche Standard-Header (In-Reply-To, References)
    for header in ['In-Reply-To', 'References']:
        value = (parsed.get(header) or '').strip()
        if value:
            match = ses_pattern.search(value)
            if match:
                found_id = match.group(0)
                # Nur nehmen wenn es NICHT die aktuelle Bounce-ID ist
                if found_id != current_id:
                    log(f"  Found Message-ID in {header}: {found_id}")
                    return found_id
    
    # 2. Durchsuche den kompletten Email-Body (inkl. ALLE Attachments/Parts)
    try:
        body_text = ''
        
        # Hole den kompletten Body als String
        if parsed.is_multipart():
            for part in parsed.walk():
                content_type = part.get_content_type()
                
                # SPEZIALFALL: message/rfc822 (eingebettete Messages)
                if content_type == 'message/rfc822':
                    log(f"  Processing embedded message/rfc822", 'DEBUG')
                    try:
                        # get_payload() gibt eine Liste mit einem EmailMessage-Objekt zurück!
                        payload = part.get_payload()
                        if isinstance(payload, list) and len(payload) > 0:
                            embedded_msg = payload[0]
                            # Hole Message-ID aus dem eingebetteten Message
                            embedded_id = (embedded_msg.get('Message-ID') or '').strip()
                            match = ses_pattern.search(embedded_id)
                            if match:
                                found_id = match.group(0)
                                log(f"  Found ID in embedded msg: {found_id}", 'DEBUG')
                                # Nur nehmen wenn es NICHT die aktuelle Bounce-ID ist
                                if found_id != current_id:
                                    log(f"  ✓ Found Message-ID in embedded message: {found_id}")
                                    return found_id
                            # Fallback: Konvertiere eingebettete Message zu String
                            body_text += embedded_msg.as_string()
                    except Exception as e:
                        log(f"  Warning: Could not process embedded message: {e}", 'WARNING')
                
                # Durchsuche ALLE anderen Parts (außer Binärdaten wie images)
                elif content_type.startswith('text/') or content_type.startswith('application/'):
                    try:
                        payload = part.get_payload(decode=True)
                        if payload:
                            # Versuche als UTF-8, fallback auf Latin-1
                            try:
                                body_text += payload.decode('utf-8', errors='ignore')
                            except:
                                try:
                                    body_text += payload.decode('latin-1', errors='ignore')
                                except:
                                    # Letzter Versuch: als ASCII mit ignore
                                    body_text += str(payload, errors='ignore')
                    except:
                        # Falls decode fehlschlägt, String-Payload holen
                        payload = part.get_payload()
                        if isinstance(payload, str):
                            body_text += payload
        else:
            # Nicht-Multipart Message
            payload = parsed.get_payload(decode=True)
            if payload:
                try:
                    body_text = payload.decode('utf-8', errors='ignore')
                except:
                    body_text = payload.decode('latin-1', errors='ignore')
        
        # Suche alle SES Message-IDs im Body
        matches = ses_pattern.findall(body_text)
        if matches:
            log(f"  Found {len(matches)} total IDs in body: {matches}", 'DEBUG')
            # Filtere die aktuelle Bounce-ID raus
            candidates = [m for m in matches if m != current_id]
            
            if candidates:
                # Nehme die ERSTE der verbleibenden (meist die Original-ID)
                log(f"  Found {len(matches)} SES Message-ID(s) in body, using first (not bounce): {candidates[0]}")
                return candidates[0]
            else:
                log(f"  Found {len(matches)} SES Message-ID(s) but all match the bounce ID")
    
    except Exception as e:
        log(f"  Warning: Could not search body for Message-ID: {e}", 'WARNING')
    
    return None


def test_with_file(filepath: str):
    """Test mit einer echten Email-Datei"""
    print(f"\n{'='*70}")
    print(f"Testing: {filepath}")
    print('='*70)
    
    with open(filepath, 'rb') as f:
        raw_bytes = f.read()
    
    parsed = BytesParser(policy=SMTPPolicy).parsebytes(raw_bytes)
    
    print(f"\nEmail Headers:")
    print(f"  From: {parsed.get('From')}")
    print(f"  To: {parsed.get('To')}")
    print(f"  Subject: {parsed.get('Subject')}")
    print(f"  Message-ID: {parsed.get('Message-ID')}")
    print(f"  In-Reply-To: {parsed.get('In-Reply-To')}")
    print(f"  References: {parsed.get('References')}")
    
    print(f"\n--- EXTRACTION ---")
    result = extract_original_message_id(parsed)
    
    print(f"\n{'='*70}")
    print(f"RESULT: {result}")
    print('='*70)
    
    return result


if __name__ == '__main__':
    import sys
    
    if len(sys.argv) > 1:
        # Email-Datei als Argument
        result = test_with_file(sys.argv[1])
        
        # Exit code: 0 = success (ID found), 1 = failure (no ID)
        sys.exit(0 if result else 1)
    else:
        print("Usage: python3 test_extract_v2.py <email_file>")
        sys.exit(1)