text: #ifndef _ofxMessage_h_
  #define _ofxMessage_h_
  
  #include "ofxCore.h"
  
  /*
  Software License :
  
  Copyright (c) 2003-2009, The Open Effects Association Ltd. All rights reserved.
  
  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:
  
      * Redistributions of source code must retain the above copyright notice,
        this list of conditions and the following disclaimer.
      * Redistributions in binary form must reproduce the above copyright notice,
        this list of conditions and the following disclaimer in the documentation
        and/or other materials provided with the distribution.
      * Neither the name The Open Effects Association Ltd, nor the names of its 
        contributors may be used to endorse or promote products derived from this
        software without specific prior written permission.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
  ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
  
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  #define kOfxMessageSuite "OfxMessageSuite"
  
  
  /** @brief String used to type fatal error messages
  
      Fatal error messages should only be posted by a plugin when it can no longer continue operation.
   */
  #define kOfxMessageFatal "OfxMessageFatal"
  
  /** @brief String used to type error messages 
  
      Ordinary error messages should be posted when there is an error in operation that is recoverable by
      user intervention.
  */
  #define kOfxMessageError "OfxMessageError"
  
  /** @brief String used to type warning messages 
  
      Warnings indicate states that allow for operations to proceed, but are not necessarily optimal.
  */
  #define kOfxMessageWarning "OfxMessageWarning"
  
  /** @brief String used to type simple ordinary messages 
  
      Ordinary messages simply convey information from the plugin directly to the user.
  */
  #define kOfxMessageMessage "OfxMessageMessage"
  
  /** @brief String used to type log messages 
  
      Log messages are written out to a log and not to the end user.
  */
  #define kOfxMessageLog "OfxMessageLog"
  
  /** @brief String used to type yes/no messages
  
      The host is to enter a modal state which waits for the user to respond yes or no. 
  The OfxMessageSuiteV1::message function which posted the message will only return after 
  the user responds. When asking a question, the OfxStatus code returned by the message function will be,
      - kOfxStatReplyYes - if the user replied 'yes' to the question
      - kOfxStatReplyNo - if the user replied 'no' to the question
      - some error code if an error was encounterred
  
      It is an error to post a question message if the plugin is not in an interactive session.
   */
  #define kOfxMessageQuestion "OfxMessageQuestion"
  
  /** @brief The OFX suite that allows a plug-in to pass messages back to a user. The V2 suite extends on this
      in a backwards compatible manner.
   */
  typedef struct OfxMessageSuiteV1 {
  
    /** @brief Post a message on the host, using printf style varargs
  
        \arg handle     - effect handle (descriptor or instance) the message should be associated with, may be null
        \arg messageType - string describing the kind of message to post, one of the kOfxMessageType* constants
        \arg messageId - plugin specified id to associate with this message. If overriding the message in XML resource, the message is identified with this, this may be NULL, or "", in which case no override will occur,
        \arg format    - printf style format string
        \arg ...       - printf style varargs list to print
  
  \returns 
    - ::kOfxStatOK - if the message was sucessfully posted 
    - ::kOfxStatReplyYes - if the message was of type  kOfxMessageQuestion and the user reply yes
    - ::kOfxStatReplyNo - if the message was of type kOfxMessageQuestion and the user reply no
    - ::kOfxStatFailed - if the message could not be posted for some reason
  
     */
    OfxStatus (*message)(void *handle,
  		       const char *messageType,
  		       const char *messageId,
  		       const char *format,
  		       ...);
  
  } OfxMessageSuiteV1;
  
  /** @brief The OFX suite that allows a plug-in to pass messages back to a user.
  
      This extends OfxMessageSuiteV1, and should be considered a replacement to version 1. 
  
      Note that this suite has been extended in backwards compatible manner, so that a host can return this struct
      for both V1 and V2.
   */
  typedef struct OfxMessageSuiteV2 {
  
    /** @brief Post a transient message on the host, using printf style varargs. Same as the V1 message suite call.
  
        \arg handle     - effect handle (descriptor or instance) the message should be associated with, may be null
        \arg messageType - string describing the kind of message to post, one of the kOfxMessageType* constants
        \arg messageId - plugin specified id to associate with this message. If overriding the message in XML resource, the message is identified with this, this may be NULL, or "", in which case no override will occur,
        \arg format    - printf style format string
        \arg ...       - printf style varargs list to print
  
        \returns 
        - ::kOfxStatOK - if the message was sucessfully posted 
        - ::kOfxStatReplyYes - if the message was of type  kOfxMessageQuestion and the user reply yes
        - ::kOfxStatReplyNo - if the message was of type kOfxMessageQuestion and the user reply no
        - ::kOfxStatFailed - if the message could not be posted for some reason
     */
    OfxStatus (*message)(void *handle,
  		       const char *messageType,
  		       const char *messageId,
  		       const char *format,
  		       ...);
  
    /** @brief Post a persistent message on an effect, using printf style varargs, and set error states. New for V2 message suite.
  
        \arg handle     - effect instance handle the message should be associated with, may NOT be null,
        \arg messageType - string describing the kind of message to post, should be one of...
              - kOfxMessageError
              - kOfxMessageWarning
              - kOfxMessageMessage            
        \arg messageId - plugin specified id to associate with this message. If overriding the message in XML resource, the message is identified with this, this may be NULL, or "", in which case no override will occur,
        \arg format    - printf style format string
        \arg ...       - printf style varargs list to print
  
        \returns 
          - ::kOfxStatOK - if the message was sucessfully posted 
          - ::kOfxStatErrBadHandle - the handle was rubbish
          - ::kOfxStatFailed - if the message could not be posted for some reason
  
       Persistent messages are associated with an effect handle until explicitly cleared by an effect. So if an error message is posted the error state, and associated message will persist and be displayed on the effect appropriately. (eg: draw a node in red on a node based compostor and display the message when clicked on).
  
       If \e messageType is error or warning, associated error states should be flagged on host applications. Posting an error message implies that the host cannot proceeed, a warning allows the host to proceed, whilst a simple message should have no stop anything.
     */
    OfxStatus (*setPersistentMessage)(void *handle,
                                      const char *messageType,
                                      const char *messageId,
                                      const char *format,
                                      ...);
  
    
    /** @brief Clears any persistent message on an effect handle that was set by OfxMessageSuiteV2::setPersistentMessage. New for V2 message suite.
  
        \arg handle     - effect instance handle messages should be cleared from.
        \arg handle     - effect handle (descriptor or instance) 
  
        \returns 
          - ::kOfxStatOK - if the message was sucessfully cleared
          - ::kOfxStatErrBadHandle - the handle was rubbish
          - ::kOfxStatFailed - if the message could not be cleared for some reason
  
       Clearing a message will clear any associated error state.
    */
    OfxStatus (*clearPersistentMessage)(void *handle);
  
  } OfxMessageSuiteV2;
  
  /** @file ofxMessage.h
      This file contains the Host API for end user message communication.
  */
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif
  