#include once "windows.bi"
#include once "win/wininet.bi"

' Function to check the host certificate for validity
Function CheckCertificate(hRequest As HINTERNET) As Boolean
    Dim As DWORD dwFlags, dwBuffLen = Sizeof(DWORD)
    If InternetQueryOption(hRequest, INTERNET_OPTION_SECURITY_FLAGS, @dwFlags, @dwBuffLen) Then
        If (dwFlags And SECURITY_FLAG_IGNORE_UNKNOWN_CA) = 0 Then Return True
    End If
    Return False
End Function

' Main program
Dim As HINTERNET hInternet, hConnect, hRequest
Dim As String url = "https://www.w3.org/"
Dim As String buffer
Dim As DWORD bytesRead

hInternet = InternetOpen("FreeBASIC HTTP Request", INTERNET_OPEN_TYPE_DIRECT, null, null, 0)
If hInternet Then
    hConnect = InternetConnect(hInternet, "www.w3.org", INTERNET_DEFAULT_HTTPS_PORT, null, null, INTERNET_SERVICE_HTTP, 0, 0)
    If hConnect Then
        hRequest = HttpOpenRequest(hConnect, "GET", "/", null, null, null, INTERNET_FLAG_SECURE, 0)
        If hRequest Then
            If HttpSendRequest(hRequest, null, 0, null, 0) Then
                If CheckCertificate(hRequest) Then
                    Do
                        buffer = Space(1024)
                        If InternetReadFile(hRequest, Strptr(buffer), Len(buffer), @bytesRead) = 0 Then Exit Do
                        If bytesRead = 0 Then Exit Do
                        Print Left(buffer, bytesRead);
                    Loop
                Else
                    Print "Invalid certificate."
                End If
            Else
                Print "Failed to send request."
            End If
            InternetCloseHandle(hRequest)
        Else
            Print "Failed to open request."
        End If
        InternetCloseHandle(hConnect)
    Else
        Print "Failed to connect."
    End If
    InternetCloseHandle(hInternet)
Else
    Print "Failed to open internet."
End If

Sleep