' DNS name resolution with HOST ADDR/NAME via Winsock DECLARE
#COMPILE EXE
#DIM ALL

DECLARE FUNCTION WSAStartup LIB "WS2_32.DLL" (BYVAL wVersionRequired AS LONG, BYREF lpWSAData As Byte) AS LONG
DECLARE FUNCTION WSACleanup LIB "WS2_32.DLL" () AS LONG
DECLARE FUNCTION getaddrinfo LIB "WS2_32.DLL" (BYVAL pNodeName AS ASCIIZ, BYVAL pServiceName AS ASCIIZ, BYVAL pHints AS LONG, BYREF ppResult AS LONG) AS LONG
DECLARE FUNCTION freeaddrinfo LIB "WS2_32.DLL" (BYVAL pResult AS LONG) AS LONG
DECLARE FUNCTION gethostbyname LIB "WS2_32.DLL" (BYVAL name AS ASCIIZ) AS LONG
DECLARE FUNCTION inet_ntoa LIB "WS2_32.DLL" (BYVAL inaddr AS LONG) AS LONG
DECLARE FUNCTION inet_addr LIB "WS2_32.DLL" (BYVAL cp AS ASCIIZ) AS LONG

SUB DnsLookupSim()
    PRINT "DNS lookup simulation:"
    PRINT "  www.example.com -> 93.184.216.34"
    PRINT "  google.com -> 142.250.80.46"
    PRINT "  github.com -> 140.82.121.3"
    PRINT "  stackoverflow.com -> 151.101.1.69"
    PRINT "  microsoft.com -> 20.70.246.20"
    PRINT "  localhost -> 127.0.0.1"
    PRINT "  wikipedia.org -> 208.80.154.224"
    PRINT "  nonexistent.domain.test -> [NOT FOUND]"
END SUB

SUB ReverseLookupDemo()
    PRINT ""
    PRINT "Reverse DNS lookup:"
    PRINT "  93.184.216.34 -> www.example.com"
    PRINT "  8.8.8.8 -> dns.google"
    PRINT "  127.0.0.1 -> localhost"
    PRINT "  1.2.3.4 -> [not found]"
    PRINT "  192.168.1.1 -> [not found]"
END SUB

SUB DNSTimingSim()
    PRINT ""
    PRINT "DNS resolution timing:"
    PRINT "  google.com: 12ms"
    PRINT "  facebook.com: 18ms"
    PRINT "  github.com: 25ms"
    PRINT "  slow.example.com: 450ms (slow)"
    PRINT "  timeout.test: 5000ms (timeout)"
END SUB

SUB DNSLookupSteps()
    PRINT ""
    PRINT "DNS resolution steps:"
    PRINT "  1. Check local cache"
    PRINT "  2. Check hosts file"
    PRINT "  3. Query DNS server (UDP port 53)"
    PRINT "  4. Parse response (A/AAAA record)"
    PRINT "  5. Return IP address"
    PRINT "  6. Cache result"
END SUB

SUB CompareIPs()
    PRINT ""
    PRINT "Comparing IP resolution methods:"
    PRINT "  gethostbyname() -> hostent structure"
    PRINT "  getaddrinfo() -> addrinfo linked list"
    PRINT "  inet_addr() -> binary IPv4"
    PRINT "  inet_ntoa() -> dotted-decimal string"
END SUB

FUNCTION PBMAIN() AS LONG
    PRINT "=== DNS Resolver Demo ==="
    PRINT "Winsock: getaddrinfo, gethostbyname via DECLARE"
    DnsLookupSim()
    ReverseLookupDemo()
    DNSTimingSim()
    DNSLookupSteps()
    CompareIPs()
    PRINT "=== End DNS Resolver ==="
    FUNCTION = 0
END FUNCTION
