;============================================================
;   iron_dns.hsp — DNS ルックアップ (.NET版)
;
;   System.Net.Dns を使用。正引き / 全 IP 取得 / 逆引きに対応。
;   hsp3net 専用。
;
;   API:
;     dns_lookup "hostname", ip          正引き → stat (0=成功)
;     dns_lookup_all "hostname", ips     全 IP 取得 → stat (IP数)
;     dns_reverse "ip", hostname         逆引き → stat (0=成功)
;
;   例:
;     #include "iron_dns.hsp"
;     dns_lookup "www.google.com", ip
;     if stat == 0 : mes "IP: " + ip
;
;     dns_lookup_all "www.google.com", ips
;     mes "" + stat + " 件の IP:"
;     mes ips
;
;     dns_reverse "8.8.8.8", host
;     if stat == 0 : mes "Hostname: " + host
;============================================================

#ifndef __iron_dns_hsp__
#define __iron_dns_hsp__

#module iron_dns

dim _dns_cs_loaded, 1

#deffunc _dns_load_cs
	if _dns_cs_loaded : return
	sdim cs, 4096
	cs  = "using System;using System.Net;using System.Text;"
	cs += "public class HspDns {"
	cs += "  public static string Lookup(string host) {"
	cs += "    try { var ips=Dns.GetHostAddresses(host);"
	cs += "    if(ips.Length==0) return \"-1|no result\";"
	cs += "    return \"0|\"+ips[0].ToString(); }"
	cs += "    catch(Exception e) { return \"-1|\"+e.Message; } }"
	cs += "  public static string LookupAll(string host) {"
	cs += "    try { var ips=Dns.GetHostAddresses(host);"
	cs += "    var sb=new StringBuilder();"
	cs += "    foreach(var ip in ips) { if(sb.Length>0) sb.Append(\"\\n\"); sb.Append(ip.ToString()); }"
	cs += "    return ips.Length+\"|\"+sb.ToString(); }"
	cs += "    catch(Exception e) { return \"-1|\"+e.Message; } }"
	cs += "  public static string Reverse(string ip) {"
	cs += "    try { var entry=Dns.GetHostEntry(IPAddress.Parse(ip));"
	cs += "    return \"0|\"+entry.HostName; }"
	cs += "    catch(Exception e) { return \"-1|\"+e.Message; } }"
	cs += "}"
	loadnet cs, 3
	_dns_cs_loaded = 1
	return

;------------------------------------------------------------
; dns_lookup "hostname", var_ip
;   ホスト名から IP アドレスを取得。stat=0 で成功。
;------------------------------------------------------------
#deffunc dns_lookup str hostname, var out_ip, \
	local pHelper, local pResult, local s, local p
	_dns_load_cs
	sdim out_ip, 256
	newnet pHelper, "", "HspDns", 1
	netres pResult
	mcall pHelper, "Lookup", hostname
	s = nettoval(pResult, 2)
	p = instr(s, 0, "|")
	if p < 0 : return -1
	rc = int(strmid(s, 0, p))
	out_ip = strmid(s, p + 1, strlen(s) - p - 1)
	return rc

;------------------------------------------------------------
; dns_lookup_all "hostname", var_ips
;   全 IP アドレスを改行区切りで取得。stat=IP 数。
;------------------------------------------------------------
#deffunc dns_lookup_all str hostname, var out_ips, \
	local pHelper, local pResult, local s, local p
	_dns_load_cs
	sdim out_ips, 4096
	newnet pHelper, "", "HspDns", 1
	netres pResult
	mcall pHelper, "LookupAll", hostname
	s = nettoval(pResult, 2)
	p = instr(s, 0, "|")
	if p < 0 : return -1
	rc = int(strmid(s, 0, p))
	out_ips = strmid(s, p + 1, strlen(s) - p - 1)
	if rc < 0 : return 0
	return rc

;------------------------------------------------------------
; dns_reverse "ip", var_hostname
;   IP アドレスからホスト名を逆引き。stat=0 で成功。
;------------------------------------------------------------
#deffunc dns_reverse str ip_addr, var out_hostname, \
	local pHelper, local pResult, local s, local p
	_dns_load_cs
	sdim out_hostname, 256
	newnet pHelper, "", "HspDns", 1
	netres pResult
	mcall pHelper, "Reverse", ip_addr
	s = nettoval(pResult, 2)
	p = instr(s, 0, "|")
	if p < 0 : return -1
	rc = int(strmid(s, 0, p))
	out_hostname = strmid(s, p + 1, strlen(s) - p - 1)
	return rc

#global

#endif