(DataFlex) IMAP Search with THREAD Semantics

Demonstrates how to search an IMAP mailbox and return message numbers grouped together in parent/child relationships based on which messages are replies to others.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoImap
    Variant vJson
    Handle hoJson
    Integer iNumThreads
    Variant vArr
    Handle hoArr
    Integer iThreadSize
    Integer i
    Variant vSubArr
    Handle hoSubArr
    String sTemp1
    Integer iTemp1

    Move False To iSuccess

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

    Get Create (RefClass(cComChilkatImap)) To hoImap
    If (Not(IsComObjectCreated(hoImap))) Begin
        Send CreateComObject of hoImap
    End

    // Connect to your IMAP server and authenticate..
    Set ComSsl Of hoImap To True
    Set ComPort Of hoImap To 993
    Get ComConnect Of hoImap "imap.mail.us-west-2.awsapps.com" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComLogin Of hoImap "myLogin" "myPassword" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Select a mailbox
    Get ComSelectMailbox Of hoImap "Inbox" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Search for all message having the letter 'a' somewhere in the Subject,
    // and return the messages as JSON.
    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End
    Get pvComObject of hoJson to vJson
    Get ComQueryThread Of hoImap "REFERENCES" "SUBJECT a" True vJson To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoImap To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // The IMAP server will return a raw response with a format such as this:  (2)(3 6 (4 23)(44 7 96))

    // In tree form, it's like this:
    // 
    //             -- 2
    //             -- 3
    //                 \-- 6
    //                    |-- 4
    //                    |      \-- 23
    //                    |
    //                    |-- 44
    //                               \-- 7
    //                                       \-- 96
    // 

    // It means there are 2 main threads returned, but the 2nd thread splits into two sub-threads.
    // In total, we can think of it as 3 threads -- 2 main threads (with no parents) and one sub-thread w/ a parent.
    // 
    // - The 1st thread contains the message 2, and has no parent thread.
    // - The 2nd thread contains the messages 3, 6, 4, 23, and has no parent thread.
    // - The 3rd thread contains the messages 44, 7, 96 and the parent thread is message 6.
    // 

    // (Yes, this is all highly confusing...)

    // Chilkat will return the above sample response as JSON that looks like this:

    // {
    //   "threads": [
    //     [2],
    //     [3, 6, [4, 23], [44, 7, 96]]
    //   ]
    // }
    // 

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON
    // In this case, the online tool can help you get a feel for how to write the JSON parsing code..

    Get ComSizeOfArray Of hoJson "threads" To iNumThreads
    Showln "The total number of top-level threads is " iNumThreads

    // Let's say we wanted to get the messages in the thread 3, 6, 4, 23.
    // We always follow the 1st branch to the bottom, ignoring the other branches.
    // For example, if we had  [3, 5, [4, 23, [55, 56, 57], [68, 69]], [44, 7, 96]]
    // then the thread would be 3, 5, 4, 43, 55, 56, 57

    // For testing, let's substitute the response from the IMAP server with this sample:
    Get ComLoad Of hoJson '{"threads": [[2], [3, 5, [4, 23, [55, 56, 57], [68, 69]], [44, 7, 96]]]}' To iSuccess

    // Begin with the 2nd top-level thread, which is at index 1.
    Showln "Following the 2nd top level thread..."
    Get ComArrayOf Of hoJson "threads[1]" To vArr
    If (IsComObject(vArr)) Begin
        Get Create (RefClass(cComChilkatJsonArray)) To hoArr
        Set pvComObject Of hoArr To vArr
    End
    Get ComSize Of hoArr To iThreadSize
    Move 0 To i
    While (i < iThreadSize)
        // Do we have an array or integer at this position?
        Get ComTypeAt Of hoArr i To iTemp1
        If (iTemp1 = 4) Begin
            // This is a sub-array.
            Get ComArrayAt Of hoArr i To vSubArr
            If (IsComObject(vSubArr)) Begin
                Get Create (RefClass(cComChilkatJsonArray)) To hoSubArr
                Set pvComObject Of hoSubArr To vSubArr
            End
            Send Destroy of hoArr
            // Follow the sub-array starting at the 1st position..
            Move hoSubArr To hoArr
            Move 0 To i
            Get ComSize Of hoArr To iThreadSize
        End
        Else Begin
            // Must be a single integer.
            Get ComIntAt Of hoArr i To iTemp1
            Showln iTemp1
            Move (i + 1) To i
        End

    Loop

    // The output is:
    // 
    // Following the 2nd top level thread...
    // 3
    // 5
    // 4
    // 23
    // 55
    // 56
    // 57


End_Procedure