/* Copyright (c) 2011 The Chromium Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

/* This file defines the API for handling the passing of data types between
 * your module and the page.
 */

/* PP_VarType is an enumeration of the different types that can be contained
 * within a PP_VAR structure.
 */
enum PP_VarType {
  /*
   * An undefined value.
   */
  PP_VARTYPE_UNDEFINED = 0,

  /*
   * A NULL value. This is similar to undefined, but JavaScript differentiates
   * the two so we expose it here as well.
   */
  PP_VARTYPE_NULL = 1,

  /*
   * A boolean value, use the as_bool member of the var.
   */
  PP_VARTYPE_BOOL = 2,

  /*
   * A 32-bit integer value. Use the as_int member of the var.
   */
  PP_VARTYPE_INT32 = 3,

  /*
   * A double-precision floating point value. Use the as_double member of the
   * var.
   */
  PP_VARTYPE_DOUBLE = 4,

  /*
   * The Var represents a string. The as_id field is used to identify the
   * string, which may be created and retrieved from the PPB_Var interface.
   */
  PP_VARTYPE_STRING = 5,

  /*
   * Represents a JavaScript object. This vartype is not currently usable
   * from plugins, although it is used internally for some tasks.
   */
  PP_VARTYPE_OBJECT = 6,

  /*
   * Arrays and dictionaries are not currently supported but will be added
   * in future revisions. These objects are reference counted so be sure
   * to properly AddRef/Release them as you would with strings to ensure your
   * plugin will continue to work with future versions of the API.
   */
  PP_VARTYPE_ARRAY = 7,
  PP_VARTYPE_DICTIONARY = 8
};


/* This structure contains the various elements type within the PP_VAR. */
[union] struct PP_VarValue {
  /* Value if type is PP_VARTYPE_BOOL. */
  PP_Bool as_bool;
  
  /* Value if type is PP_VARTYPE_INT32. */
  int32_t as_int;
  
  /* Value if type is PP_VARTYPE_DOUBLE. */
  double_t as_double;
  
  /* Internal ID for strings and objects. The identifier is an opaque handle
   * assigned by the browser to the plugin. It is guaranteed never to be 0,
   * so a plugin can initialize this ID to 0 to indicate a "NULL handle."
   */
  int64_t as_id;
};

/* The PP_VAR struct is a variant data type and can contain any
 * value of one of the types named in the PP_VarType enum. This structure is
 * for passing data between native code which can be strongly typed and the
 * browser (JavaScript) which isn't strongly typed.
 *
 * JavaScript has a "number" type for holding a number, and does not
 * differentiate between floating point and integer numbers. The
 * JavaScript operations will try to optimize operations by using
 * integers when possible, but could end up with doubles. Therefore,
 * you can't assume a numeric PP_Var will be the type you expect.
 * Your code should be capable of handling either int32_t or double for
 * numeric PP_Vars sent from JavaScript.
 */
[passByValue] struct PP_Var {
  /* Type. */
  PP_VarType type;
  
  /* Type-dependent value. */
  PP_VarValue value;
};