#!/usr/bin/env python3
"""
Configuration management for unified email worker
"""

import os
from dataclasses import dataclass
from typing import Set


@dataclass
class Config:
    """Worker Configuration"""
    # AWS
    aws_region: str = os.environ.get('AWS_REGION', 'us-east-2')
    
    # Domains to process
    domains_list: str = os.environ.get('DOMAINS', '')
    domains_file: str = os.environ.get('DOMAINS_FILE', '/etc/email-worker/domains.txt')
    
    # Worker Settings
    worker_threads: int = int(os.environ.get('WORKER_THREADS', '10'))
    poll_interval: int = int(os.environ.get('POLL_INTERVAL', '20'))
    max_messages: int = int(os.environ.get('MAX_MESSAGES', '10'))
    visibility_timeout: int = int(os.environ.get('VISIBILITY_TIMEOUT', '300'))
    
    # SMTP for delivery
    smtp_host: str = os.environ.get('SMTP_HOST', 'localhost')
    smtp_port: int = int(os.environ.get('SMTP_PORT', '25'))
    smtp_use_tls: bool = os.environ.get('SMTP_USE_TLS', 'false').lower() == 'true'
    smtp_user: str = os.environ.get('SMTP_USER', '')
    smtp_pass: str = os.environ.get('SMTP_PASS', '')
    smtp_pool_size: int = int(os.environ.get('SMTP_POOL_SIZE', '5'))
    
    # Internal SMTP (bypasses transport_maps)
    internal_smtp_port: int = int(os.environ.get('INTERNAL_SMTP_PORT', '2525'))
    
    # LMTP for local delivery (bypasses Postfix transport_maps)
    lmtp_enabled: bool = os.environ.get('LMTP_ENABLED', 'false').lower() == 'true'
    lmtp_host: str = os.environ.get('LMTP_HOST', 'localhost')
    lmtp_port: int = int(os.environ.get('LMTP_PORT', '24'))
    
    # DynamoDB Tables
    rules_table: str = os.environ.get('DYNAMODB_RULES_TABLE', 'email-rules')
    messages_table: str = os.environ.get('DYNAMODB_MESSAGES_TABLE', 'ses-outbound-messages')
    blocked_table: str = os.environ.get('DYNAMODB_BLOCKED_TABLE', 'email-blocked-senders')
    
    # Bounce Handling
    bounce_lookup_retries: int = int(os.environ.get('BOUNCE_LOOKUP_RETRIES', '3'))
    bounce_lookup_delay: float = float(os.environ.get('BOUNCE_LOOKUP_DELAY', '1.0'))
    
    # Monitoring
    metrics_port: int = int(os.environ.get('METRICS_PORT', '8000'))
    health_port: int = int(os.environ.get('HEALTH_PORT', '8080'))


# Global configuration instance
config = Config()

# Global set of managed domains (populated at startup)
MANAGED_DOMAINS: Set[str] = set()


def load_domains() -> list[str]:
    """Load domains from config and populate MANAGED_DOMAINS global"""
    global MANAGED_DOMAINS
    domains = []
    
    if config.domains_list:
        domains.extend([d.strip() for d in config.domains_list.split(',') if d.strip()])
    
    if os.path.exists(config.domains_file):
        with open(config.domains_file, 'r') as f:
            for line in f:
                domain = line.strip()
                if domain and not domain.startswith('#'):
                    domains.append(domain)
    
    domains = list(set(domains))
    MANAGED_DOMAINS = set(d.lower() for d in domains)
    
    return domains


def is_internal_address(email_address: str) -> bool:
    """Check if email address belongs to one of our managed domains"""
    if '@' not in email_address:
        return False
    domain = email_address.split('@')[1].lower()
    return domain in MANAGED_DOMAINS


def domain_to_queue_name(domain: str) -> str:
    """Convert domain to SQS queue name"""
    return domain.replace('.', '-') + '-queue'


def domain_to_bucket_name(domain: str) -> str:
    """Convert domain to S3 bucket name"""
    return domain.replace('.', '-') + '-emails'