(C++) Download IMAP Message Set using FetchBundle

Demonstrates how to read IMAP emails using the FetchBundle method.

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#include <CkImap.h>
#include <CkMessageSet.h>
#include <CkEmailBundle.h>
#include <CkEmail.h>

void ChilkatSample(void)
    {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkImap imap;

    // Connect using TLS.
    imap.put_Ssl(true);
    imap.put_Port(993);
    bool success = imap.Connect("imap.example.com");
    if (success != true) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    // Authenticate
    success = imap.Login("email_account_login","email_account_password");
    if (success != true) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    // Select an IMAP mailbox
    success = imap.SelectMailbox("Inbox");
    if (success != true) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    // Search for messages with the word "test" in the subject.
    bool fetchUids = true;
    CkMessageSet *messageSet = imap.Search("Subject test",fetchUids);
    if (imap.get_LastMethodSuccess() != true) {
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    // Download the messages in a single call to FetchBundle.
    // 
    // This only makes sense if the number of emails to be downloaded is not too large.  
    // For example, you wouldn't want to download 10000 emails in a single call to FetchBundle.
    // Why? For two reasons:  (1) It could potentially cause an out-of-memory condition, and 
    // (2) it would take an extremely large amount of time.  The longer the amount of time,
    // the greater the likelihood of some kind of external networking or server problem occuring,
    // and if it happens, then you would need to re-download everything from the beginning again.
    // For large numbers of emails, it's better to loop over the emails in the message set
    // and download/process one at a time as shown here: Download IMAP Messages One at a Time
    // Downloading one message at a time makes it possible to resume the downloads rather than restart the entire operation all over again.

    // If the message set is reasonable in size, you can download all at once using FetchBundle:

    std::cout << "Number of messages = " << messageSet->get_Count() << "\r\n";

    CkEmailBundle *bundle = imap.FetchBundle(*messageSet);
    if (imap.get_LastMethodSuccess() == false) {
        delete messageSet;
        std::cout << imap.lastErrorText() << "\r\n";
        return;
    }

    // Display the Subject and From of each email.
    int i = 0;
    int numEmails = bundle->get_MessageCount();
    while (i < numEmails) {
        CkEmail *email = bundle->GetEmail(i);

        std::cout << email->getHeaderField("Date") << "\r\n";
        std::cout << email->subject() << "\r\n";
        std::cout << email->ck_from() << "\r\n";
        std::cout << "--" << "\r\n";

        delete email;
        i = i + 1;
    }

    delete messageSet;
    delete bundle;
    }