1/*
2 *  Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef WebScriptObject_h
27#define WebScriptObject_h
28
29#import <Foundation/Foundation.h>
30#import <JavaScriptCore/JSBase.h>
31#import <JavaScriptCore/WebKitAvailability.h>
32
33#if WEBKIT_VERSION_MAX_ALLOWED >= WEBKIT_VERSION_1_3
34
35// NSObject (WebScripting) -----------------------------------------------------
36
37/*
38    Classes may implement one or more methods in WebScripting to export interfaces
39    to WebKit's JavaScript environment.
40
41    By default, no properties or functions are exported. A class must implement
42    +isKeyExcludedFromWebScript: and/or +isSelectorExcludedFromWebScript: to
43    expose selected properties and methods, respectively, to JavaScript.
44
45    Access to exported properties is done using KVC -- specifically, the following
46    KVC methods:
47
48        - (void)setValue:(id)value forKey:(NSString *)key
49        - (id)valueForKey:(NSString *)key
50
51    Clients may also intercept property set/get operations that are made by the
52    scripting environment for properties that are not exported. This is done using
53    the KVC methods:
54
55        - (void)setValue:(id)value forUndefinedKey:(NSString *)key
56        - (id)valueForUndefinedKey:(NSString *)key
57
58    Similarly, clients may intercept method invocations that are made by the
59    scripting environment for methods that are not exported. This is done using
60    the method:
61
62        - (id)invokeUndefinedMethodFromWebScript:(NSString *)name withArguments:(NSArray *)args;
63
64    If clients need to raise an exception in the script environment
65    they can call [WebScriptObject throwException:]. Note that throwing an
66    exception using this method will only succeed if the method that throws the exception
67    is being called within the scope of a script invocation.
68
69    Not all methods are exposed. Only those methods whose parameters and return
70    type meets the export criteria are exposed. Valid types are Objective-C instances
71    and scalars. Other types are not allowed.
72
73    Types will be converted automatically between JavaScript and Objective-C in
74    the following manner:
75
76    JavaScript              ObjC
77    ----------              ----------
78    null            =>      nil
79    undefined       =>      WebUndefined
80    number          =>      NSNumber
81    boolean         =>      CFBoolean
82    string          =>      NSString
83    object          =>      id
84
85    The object => id conversion occurs as follows: if the object wraps an underlying
86    Objective-C object (i.e., if it was created by a previous ObjC => JavaScript conversion),
87    then the underlying Objective-C object is returned. Otherwise, a new WebScriptObject
88    is created and returned.
89
90    The above conversions occur only if the declared ObjC type is an object type.
91    For primitive types like int and char, a numeric cast is performed.
92
93    ObjC                    JavaScript
94    ----                    ----------
95    NSNull          =>      null
96    nil             =>      undefined
97    WebUndefined    =>      undefined
98    CFBoolean       =>      boolean
99    NSNumber        =>      number
100    NSString        =>      string
101    NSArray         =>      array object
102    WebScriptObject =>      object
103
104    The above conversions occur only if the declared ObjC type is an object type.
105    For primitive type like int and char, a numeric cast is performed.
106*/
107@interface NSObject (WebScripting)
108
109/*!
110    @method webScriptNameForSelector:
111    @param selector The selector that will be exposed to the script environment.
112    @discussion Use the returned string as the exported name for the selector
113    in the script environment. It is the responsibility of the class to ensure
114    uniqueness of the returned name. If nil is returned or this
115    method is not implemented the default name for the selector will
116    be used. The default name concatenates the components of the
117    Objective-C selector name and replaces ':' with '_'.  '_' characters
118    are escaped with an additional '$', i.e. '_' becomes "$_". '$' are
119    also escaped, i.e.
120        Objective-C name        Default script name
121        moveTo::                move__
122        moveTo_                 moveTo$_
123        moveTo$_                moveTo$$$_
124    @result Returns the name to be used to represent the specified selector in the
125    scripting environment.
126*/
127+ (NSString *)webScriptNameForSelector:(SEL)selector;
128
129/*!
130    @method isSelectorExcludedFromWebScript:
131    @param selector The selector the will be exposed to the script environment.
132    @discussion Return NO to export the selector to the script environment.
133    Return YES to prevent the selector from being exported to the script environment.
134    If this method is not implemented on the class no selectors will be exported.
135    @result Returns YES to hide the selector, NO to export the selector.
136*/
137+ (BOOL)isSelectorExcludedFromWebScript:(SEL)selector;
138
139/*!
140    @method webScriptNameForKey:
141    @param name The name of the instance variable that will be exposed to the
142    script environment. Only instance variables that meet the export criteria will
143    be exposed.
144    @discussion Provide an alternate name for a property.
145    @result Returns the name to be used to represent the specified property in the
146    scripting environment.
147*/
148+ (NSString *)webScriptNameForKey:(const char *)name;
149
150/*!
151    @method isKeyExcludedFromWebScript:
152    @param name The name of the instance variable that will be exposed to the
153    script environment.
154    @discussion Return NO to export the property to the script environment.
155    Return YES to prevent the property from being exported to the script environment.
156    @result Returns YES to hide the property, NO to export the property.
157*/
158+ (BOOL)isKeyExcludedFromWebScript:(const char *)name;
159
160/*!
161    @method invokeUndefinedMethodFromWebScript:withArguments:
162    @param name The name of the method to invoke.
163    @param arguments The arguments to pass the method.
164    @discussion If a script attempts to invoke a method that is not exported,
165    invokeUndefinedMethodFromWebScript:withArguments: will be called.
166    @result The return value of the invocation. The value will be converted as appropriate
167    for the script environment.
168*/
169- (id)invokeUndefinedMethodFromWebScript:(NSString *)name withArguments:(NSArray *)arguments;
170
171/*!
172    @method invokeDefaultMethodWithArguments:
173    @param arguments The arguments to pass the method.
174    @discussion If a script attempts to call an exposed object as a function,
175    this method will be called.
176    @result The return value of the call. The value will be converted as appropriate
177    for the script environment.
178*/
179- (id)invokeDefaultMethodWithArguments:(NSArray *)arguments;
180
181/*!
182    @method finalizeForWebScript
183    @discussion finalizeForScript is called on objects exposed to the script
184    environment just before the script environment garbage collects the object.
185    Subsequently, any references to WebScriptObjects made by the exposed object will
186    be invalid and have undefined consequences.
187*/
188- (void)finalizeForWebScript;
189
190@end
191
192
193// WebScriptObject --------------------------------------------------
194
195@class JSValue;
196@class WebScriptObjectPrivate;
197@class WebFrame;
198
199/*!
200    @class WebScriptObject
201    @discussion WebScriptObjects are used to wrap script objects passed from
202    script environments to Objective-C. WebScriptObjects cannot be created
203    directly. In normal uses of WebKit, you gain access to the script
204    environment using the "windowScriptObject" method on WebView.
205
206    The following KVC methods are commonly used to access properties of the
207    WebScriptObject:
208
209        - (void)setValue:(id)value forKey:(NSString *)key
210        - (id)valueForKey:(NSString *)key
211
212    As it possible to remove attributes from web script objects, the following
213    additional method augments the basic KVC methods:
214
215        - (void)removeWebScriptKey:(NSString *)name;
216
217    Also, since the sparse array access allowed in script objects doesn't map well
218    to NSArray, the following methods can be used to access index based properties:
219
220        - (id)webScriptValueAtIndex:(unsigned)index;
221        - (void)setWebScriptValueAtIndex:(unsigned)index value:(id)value;
222*/
223@interface WebScriptObject : NSObject
224{
225    WebScriptObjectPrivate *_private;
226}
227
228/*!
229    @method throwException:
230    @discussion Throws an exception in the current script execution context.
231    @result Either NO if an exception could not be raised, YES otherwise.
232*/
233+ (BOOL)throwException:(NSString *)exceptionMessage;
234
235/*!
236    @method JSObject
237    @result The equivalent JSObjectRef for this WebScriptObject.
238    @discussion Use this method to bridge between the WebScriptObject and
239    JavaScriptCore APIs.
240*/
241- (JSObjectRef)JSObject WEBKIT_OBJC_METHOD_ANNOTATION(AVAILABLE_WEBKIT_VERSION_3_0_AND_LATER);
242
243/*!
244    @method callWebScriptMethod:withArguments:
245    @param name The name of the method to call in the script environment.
246    @param arguments The arguments to pass to the script environment.
247    @discussion Calls the specified method in the script environment using the
248    specified arguments.
249    @result Returns the result of calling the script method.
250    Returns WebUndefined when an exception is thrown in the script environment.
251*/
252- (id)callWebScriptMethod:(NSString *)name withArguments:(NSArray *)arguments;
253
254/*!
255    @method evaluateWebScript:
256    @param script The script to execute in the target script environment.
257    @discussion The script will be executed in the target script environment. The format
258    of the script is dependent of the target script environment.
259    @result Returns the result of evaluating the script in the script environment.
260    Returns WebUndefined when an exception is thrown in the script environment.
261*/
262- (id)evaluateWebScript:(NSString *)script;
263
264/*!
265    @method removeWebScriptKey:
266    @param name The name of the property to remove.
267    @discussion Removes the property from the object in the script environment.
268*/
269- (void)removeWebScriptKey:(NSString *)name;
270
271/*!
272    @method stringRepresentation
273    @discussion Converts the target object to a string representation. The coercion
274    of non string objects type is dependent on the script environment.
275    @result Returns the string representation of the object.
276*/
277- (NSString *)stringRepresentation;
278
279/*!
280    @method webScriptValueAtIndex:
281    @param index The index of the property to return.
282    @discussion Gets the value of the property at the specified index.
283    @result The value of the property. Returns WebUndefined when an exception is
284    thrown in the script environment.
285*/
286- (id)webScriptValueAtIndex:(unsigned)index;
287
288/*!
289    @method setWebScriptValueAtIndex:value:
290    @param index The index of the property to set.
291    @param value The value of the property to set.
292    @discussion Sets the property value at the specified index.
293*/
294- (void)setWebScriptValueAtIndex:(unsigned)index value:(id)value;
295
296/*!
297    @method setException:
298    @param description The description of the exception.
299    @discussion Raises an exception in the script environment in the context of the
300    current object.
301*/
302- (void)setException:(NSString *)description;
303
304
305#if JSC_OBJC_API_ENABLED
306/*!
307    @method JSValue
308    @result The equivalent Objective-C JSValue for this WebScriptObject.
309    @discussion Use this method to bridge between the WebScriptObject and
310    JavaScriptCore Objective-C APIs.
311*/
312- (JSValue *)JSValue;
313#endif
314
315@end
316
317
318// WebUndefined --------------------------------------------------------------
319
320/*!
321    @class WebUndefined
322*/
323@interface WebUndefined : NSObject <NSCoding, NSCopying>
324
325/*!
326    @method undefined
327    @result The WebUndefined shared instance.
328*/
329+ (WebUndefined *)undefined;
330
331@end
332
333#endif
334
335#endif // WebScriptObject_h
336