(PureBasic) 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 v9.5.0.77 or greater.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkJsonArray.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkImap.pb"

Procedure ChilkatExample()

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

    imap.i = CkImap::ckCreate()
    If imap.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Connect to your IMAP server and authenticate..
    CkImap::setCkSsl(imap, 1)
    CkImap::setCkPort(imap, 993)
    success.i = CkImap::ckConnect(imap,"imap.mail.us-west-2.awsapps.com")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    success = CkImap::ckLogin(imap,"myLogin","myPassword")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Select a mailbox
    success = CkImap::ckSelectMailbox(imap,"Inbox")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Search for all message having the letter 'a' somewhere in the Subject,
    ; and return the messages as JSON.
    json.i = CkImap::ckThreadCmd(imap,"REFERENCES","UTF-8","SUBJECT a",1)
    If CkImap::ckLastMethodSuccess(imap) = 0
        Debug CkImap::ckLastErrorText(imap)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; 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..

    numThreads.i = CkJsonObject::ckSizeOfArray(json,"threads")
    Debug "The total number of top-level threads is " + Str(numThreads)

    ; 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:
    CkJsonObject::ckLoad(json,"{" + Chr(34) + "threads" + Chr(34) + ": [[2], [3, 5, [4, 23, [55, 56, 57], [68, 69]], [44, 7, 96]]]}")

    ; Begin with the 2nd top-level thread, which is at index 1.
    Debug "Following the 2nd top level thread..."
    arr.i = CkJsonObject::ckArrayOf(json,"threads[1]")
    threadSize.i = CkJsonArray::ckSize(arr)
    i.i = 0
    While i < threadSize
        ; Do we have an array or integer at this position?
        If CkJsonArray::ckTypeAt(arr,i) = 4
            ; This is a sub-array.
            subArr.i = CkJsonArray::ckArrayAt(arr,i)
            CkJsonArray::ckDispose(arr)

            ; Follow the sub-array starting at the 1st position..
            arr = subArr
            i = 0
            threadSize = CkJsonArray::ckSize(arr)
        Else
            ; Must be a single integer.
            Debug Str(CkJsonArray::ckIntAt(arr,i))
            i = i + 1
        EndIf

    Wend

    CkJsonObject::ckDispose(json)

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


    CkImap::ckDispose(imap)


    ProcedureReturn
EndProcedure