// TypeScript/JavaScript domain validation
function isValidDomain(domain: string): boolean {
  if (!domain || domain.length > 253) {
    return false;
  }

  // RFC 1035 compliant regex
  const domainRegex = /^(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?$/i;
  
  if (!domainRegex.test(domain)) {
    return false;
  }

  // Check label length (max 63 chars)
  const labels = domain.split('.');
  for (const label of labels) {
    if (label.length > 63 || label.length === 0) {
      return false;
    }
    // Labels cannot start or end with hyphen
    if (label.startsWith('-') || label.endsWith('-')) {
      return false;
    }
  }

  return true;
}

import re

def is_valid_domain(domain: str) -> bool:
    """Validate domain name format according to RFC 1035 and RFC 1123."""
    if not domain or len(domain) > 253:
        return False
    
    # RFC 1035 compliant regex
    domain_pattern = r'^(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?$'
    
    if not re.match(domain_pattern, domain, re.IGNORECASE):
        return False
    
    # Check label length (max 63 chars)
    labels = domain.split('.')
    for label in labels:
        if len(label) > 63 or len(label) == 0:
            return False
        # Labels cannot start or end with hyphen
        if label.startswith('-') or label.endswith('-'):
            return False
    
    return True

import { IsString, Matches, MaxLength, ValidateIf } from 'class-validator';

export class DomainDto {
  @IsString()
  @MaxLength(253)
  @Matches(
    /^(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?$/i,
    {
      message: 'Invalid domain name format',
    }
  )
  domain: string;
}

// Namecheap domain availability check
async function checkDomainAvailability(domain: string): Promise<boolean> {
  const apiUser = process.env.NAMECHEAP_API_USER;
  const apiKey = process.env.NAMECHEAP_API_KEY;
  const clientIp = process.env.NAMECHEAP_CLIENT_IP;
  
  const url = `https://api.namecheap.com/xml.response?ApiUser=${apiUser}&ApiKey=${apiKey}&UserName=${apiUser}&Command=namecheap.domains.check&ClientIp=${clientIp}&DomainList=${domain}`;
  
  try {
    const response = await fetch(url);
    const xml = await response.text();
    
    // Parse XML response
    // Available domains return <DomainCheckResult Domain="example.com" Available="true"/>
    return xml.includes('Available="true"');
  } catch (error) {
    console.error('Error checking domain availability:', error);
    throw error;
  }
}

// GoDaddy domain availability check
async function checkGoDaddyAvailability(domain: string): Promise<boolean> {
  const apiKey = process.env.GODADDY_API_KEY;
  const apiSecret = process.env.GODADDY_API_SECRET;
  
  const url = `https://api.godaddy.com/v1/domains/available?domain=${domain}`;
  
  try {
    const response = await fetch(url, {
      headers: {
        'Authorization': `sso-key ${apiKey}:${apiSecret}`,
        'Content-Type': 'application/json',
      },
    });
    
    const data = await response.json();
    return data.available === true;
  } catch (error) {
    console.error('Error checking domain availability:', error);
    throw error;
  }
}

import { Injectable } from '@nestjs/common';
import { HttpService } from '@nestjs/axios';
import { firstValueFrom } from 'rxjs';

@Injectable()
export class DomainService {
  constructor(private httpService: HttpService) {}

  async checkAvailability(domain: string): Promise<boolean> {
    const apiKey = process.env.DOMAIN_API_KEY;
    const apiSecret = process.env.DOMAIN_API_SECRET;
    
    try {
      const response = await firstValueFrom(
        this.httpService.get(`https://api.example.com/domains/check`, {
          params: { domain },
          headers: {
            'Authorization': `Bearer ${apiKey}`,
          },
        })
      );
      
      return response.data.available;
    } catch (error) {
      throw new Error(`Failed to check domain availability: ${error.message}`);
    }
  }
}

function generateDomainSuggestions(keyword: string, tlds: string[] = ['com', 'io', 'net', 'org']): string[] {
  const suggestions: string[] = [];
  const sanitized = keyword.toLowerCase().replace(/[^a-z0-9-]/g, '');
  
  // Direct combinations
  for (const tld of tlds) {
    suggestions.push(`${sanitized}.${tld}`);
  }
  
  // Common prefixes
  const prefixes = ['get', 'try', 'use', 'my', 'the'];
  for (const prefix of prefixes) {
    for (const tld of tlds) {
      suggestions.push(`${prefix}${sanitized}.${tld}`);
    }
  }
  
  // Common suffixes
  const suffixes = ['app', 'hub', 'ly', 'fy', 'io'];
  for (const suffix of suffixes) {
    for (const tld of tlds) {
      suggestions.push(`${sanitized}${suffix}.${tld}`);
    }
  }
  
  return suggestions;
}

async function searchAvailableDomains(keyword: string): Promise<string[]> {
  const suggestions = generateDomainSuggestions(keyword);
  const availableDomains: string[] = [];
  
  // Check availability for all suggestions (with rate limiting)
  for (const domain of suggestions) {
    try {
      const isAvailable = await checkDomainAvailability(domain);
      if (isAvailable) {
        availableDomains.push(domain);
      }
      // Rate limiting delay
      await new Promise(resolve => setTimeout(resolve, 100));
    } catch (error) {
      console.error(`Error checking ${domain}:`, error);
    }
  }
  
  return availableDomains;
}