/*

 * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. 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.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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.

 */

#ifndef JSValueRef_h

#define JSValueRef_h

#include <JavaScriptCore/JSBase.h>

#include <JavaScriptCore/WebKitAvailability.h>

#ifndef __cplusplus

#include <stdbool.h>

#endif

/*!

@enum JSType

@abstract     A constant identifying the type of a JSValue.

@constant     kJSTypeUndefined  The unique undefined value.

@constant     kJSTypeNull       The unique null value.

@constant     kJSTypeBoolean    A primitive boolean value, one of true or false.

@constant     kJSTypeNumber     A primitive number value.

@constant     kJSTypeString     A primitive string value.

@constant     kJSTypeObject     An object value (meaning that this JSValueRef is a JSObjectRef).

*/

typedef enum {

    kJSTypeUndefined,

    kJSTypeNull,

    kJSTypeBoolean,

    kJSTypeNumber,

    kJSTypeString,

    kJSTypeObject

} JSType;

#ifdef __cplusplus

extern "C" {

#endif

/*!

@function

@abstract       Returns a JavaScript value's type.

@param ctx  The execution context to use.

@param value    The JSValue whose type you want to obtain.

@result         A value of type JSType that identifies value's type.

*/

JS_EXPORT JSType JSValueGetType(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract       Tests whether a JavaScript value's type is the undefined type.

@param ctx  The execution context to use.

@param value    The JSValue to test.

@result         true if value's type is the undefined type, otherwise false.

*/

JS_EXPORT bool JSValueIsUndefined(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract       Tests whether a JavaScript value's type is the null type.

@param ctx  The execution context to use.

@param value    The JSValue to test.

@result         true if value's type is the null type, otherwise false.

*/

JS_EXPORT bool JSValueIsNull(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract       Tests whether a JavaScript value's type is the boolean type.

@param ctx  The execution context to use.

@param value    The JSValue to test.

@result         true if value's type is the boolean type, otherwise false.

*/

JS_EXPORT bool JSValueIsBoolean(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract       Tests whether a JavaScript value's type is the number type.

@param ctx  The execution context to use.

@param value    The JSValue to test.

@result         true if value's type is the number type, otherwise false.

*/

JS_EXPORT bool JSValueIsNumber(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract       Tests whether a JavaScript value's type is the string type.

@param ctx  The execution context to use.

@param value    The JSValue to test.

@result         true if value's type is the string type, otherwise false.

*/

JS_EXPORT bool JSValueIsString(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract       Tests whether a JavaScript value's type is the object type.

@param ctx  The execution context to use.

@param value    The JSValue to test.

@result         true if value's type is the object type, otherwise false.

*/

JS_EXPORT bool JSValueIsObject(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract Tests whether a JavaScript value is an object with a given class in its class chain.

@param ctx The execution context to use.

@param value The JSValue to test.

@param jsClass The JSClass to test against.

@result true if value is an object and has jsClass in its class chain, otherwise false.

*/

JS_EXPORT bool JSValueIsObjectOfClass(JSContextRef ctx, JSValueRef value, JSClassRef jsClass);

/* Comparing values */

/*!

@function

@abstract Tests whether two JavaScript values are equal, as compared by the JS == operator.

@param ctx The execution context to use.

@param a The first value to test.

@param b The second value to test.

@param exception A pointer to a JSValueRef in which to store an exception, if any. Pass NULL if you do not care to store an exception.

@result true if the two values are equal, false if they are not equal or an exception is thrown.

*/

JS_EXPORT bool JSValueIsEqual(JSContextRef ctx, JSValueRef a, JSValueRef b, JSValueRef* exception);

/*!

@function

@abstract       Tests whether two JavaScript values are strict equal, as compared by the JS === operator.

@param ctx  The execution context to use.

@param a        The first value to test.

@param b        The second value to test.

@result         true if the two values are strict equal, otherwise false.

*/

JS_EXPORT bool JSValueIsStrictEqual(JSContextRef ctx, JSValueRef a, JSValueRef b);

/*!

@function

@abstract Tests whether a JavaScript value is an object constructed by a given constructor, as compared by the JS instanceof operator.

@param ctx The execution context to use.

@param value The JSValue to test.

@param constructor The constructor to test against.

@param exception A pointer to a JSValueRef in which to store an exception, if any. Pass NULL if you do not care to store an exception.

@result true if value is an object constructed by constructor, as compared by the JS instanceof operator, otherwise false.

*/

JS_EXPORT bool JSValueIsInstanceOfConstructor(JSContextRef ctx, JSValueRef value, JSObjectRef constructor, JSValueRef* exception);

/* Creating values */

/*!

@function

@abstract       Creates a JavaScript value of the undefined type.

@param ctx  The execution context to use.

@result         The unique undefined value.

*/

JS_EXPORT JSValueRef JSValueMakeUndefined(JSContextRef ctx);

/*!

@function

@abstract       Creates a JavaScript value of the null type.

@param ctx  The execution context to use.

@result         The unique null value.

*/

JS_EXPORT JSValueRef JSValueMakeNull(JSContextRef ctx);

/*!

@function

@abstract       Creates a JavaScript value of the boolean type.

@param ctx  The execution context to use.

@param boolean  The bool to assign to the newly created JSValue.

@result         A JSValue of the boolean type, representing the value of boolean.

*/

JS_EXPORT JSValueRef JSValueMakeBoolean(JSContextRef ctx, bool boolean);

/*!

@function

@abstract       Creates a JavaScript value of the number type.

@param ctx  The execution context to use.

@param number   The double to assign to the newly created JSValue.

@result         A JSValue of the number type, representing the value of number.

*/

JS_EXPORT JSValueRef JSValueMakeNumber(JSContextRef ctx, double number);

/*!

@function

@abstract       Creates a JavaScript value of the string type.

@param ctx  The execution context to use.

@param string   The JSString to assign to the newly created JSValue. The

 newly created JSValue retains string, and releases it upon garbage collection.

@result         A JSValue of the string type, representing the value of string.

*/

JS_EXPORT JSValueRef JSValueMakeString(JSContextRef ctx, JSStringRef string);

/* Converting to and from JSON formatted strings */

/*!

 @function

 @abstract       Creates a JavaScript value from a JSON formatted string.

 @param ctx      The execution context to use.

 @param string   The JSString containing the JSON string to be parsed.

 @result         A JSValue containing the parsed value, or NULL if the input is invalid.

 */

JS_EXPORT JSValueRef JSValueMakeFromJSONString(JSContextRef ctx, JSStringRef string) AVAILABLE_AFTER_WEBKIT_VERSION_4_0;

/*!

 @function

 @abstract       Creates a JavaScript string containing the JSON serialized representation of a JS value.

 @param ctx      The execution context to use.

 @param value    The value to serialize.

 @param indent   The number of spaces to indent when nesting.  If 0, the resulting JSON will not contains newlines.  The size of the indent is clamped to 10 spaces.

 @param exception A pointer to a JSValueRef in which to store an exception, if any. Pass NULL if you do not care to store an exception.

 @result         A JSString with the result of serialization, or NULL if an exception is thrown.

 */

JS_EXPORT JSStringRef JSValueCreateJSONString(JSContextRef ctx, JSValueRef value, unsigned indent, JSValueRef* exception) AVAILABLE_AFTER_WEBKIT_VERSION_4_0;

/* Converting to primitive values */

/*!

@function

@abstract       Converts a JavaScript value to boolean and returns the resulting boolean.

@param ctx  The execution context to use.

@param value    The JSValue to convert.

@result         The boolean result of conversion.

*/

JS_EXPORT bool JSValueToBoolean(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract       Converts a JavaScript value to number and returns the resulting number.

@param ctx  The execution context to use.

@param value    The JSValue to convert.

@param exception A pointer to a JSValueRef in which to store an exception, if any. Pass NULL if you do not care to store an exception.

@result         The numeric result of conversion, or NaN if an exception is thrown.

*/

JS_EXPORT double JSValueToNumber(JSContextRef ctx, JSValueRef value, JSValueRef* exception);

/*!

@function

@abstract       Converts a JavaScript value to string and copies the result into a JavaScript string.

@param ctx  The execution context to use.

@param value    The JSValue to convert.

@param exception A pointer to a JSValueRef in which to store an exception, if any. Pass NULL if you do not care to store an exception.

@result         A JSString with the result of conversion, or NULL if an exception is thrown. Ownership follows the Create Rule.

*/

JS_EXPORT JSStringRef JSValueToStringCopy(JSContextRef ctx, JSValueRef value, JSValueRef* exception);

/*!

@function

@abstract Converts a JavaScript value to object and returns the resulting object.

@param ctx  The execution context to use.

@param value    The JSValue to convert.

@param exception A pointer to a JSValueRef in which to store an exception, if any. Pass NULL if you do not care to store an exception.

@result         The JSObject result of conversion, or NULL if an exception is thrown.

*/

JS_EXPORT JSObjectRef JSValueToObject(JSContextRef ctx, JSValueRef value, JSValueRef* exception);

/* Garbage collection */

/*!

@function

@abstract Protects a JavaScript value from garbage collection.

@param ctx The execution context to use.

@param value The JSValue to protect.

@discussion Use this method when you want to store a JSValue in a global or on the heap, where the garbage collector will not be able to discover your reference to it.

A value may be protected multiple times and must be unprotected an equal number of times before becoming eligible for garbage collection.

*/

JS_EXPORT void JSValueProtect(JSContextRef ctx, JSValueRef value);

/*!

@function

@abstract       Unprotects a JavaScript value from garbage collection.

@param ctx      The execution context to use.

@param value    The JSValue to unprotect.

@discussion     A value may be protected multiple times and must be unprotected an 

 equal number of times before becoming eligible for garbage collection.

*/

JS_EXPORT void JSValueUnprotect(JSContextRef ctx, JSValueRef value);

#ifdef __cplusplus

}

#endif

#endif /* JSValueRef_h */