/* simplewebkit
   WebScriptObject.m

   Copyright (C) 2007 Free Software Foundation, Inc.

   Author: Dr. H. Nikolaus Schaller

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with this library; see the file COPYING.LIB.
   If not, write to the Free Software Foundation,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/

#import <WebKit/WebDOMOperations.h>
#import <WebKit/WebScriptObject.h>
#import <WebKit/WebUndefined.h>
#import "ECMAScriptParser.h"
#import "ECMAScriptEvaluator.h"

#import "Private.h"

NSString *WebScriptException=@"WebScriptException";

/* implementation of public methods */

@implementation WebScriptObject

- (id) init;
{
	if((self=[super init]))
		{
	/* predefine global variables so that they return a prototype object
		Array, Boolean, Date, Function, Math, Number, Object, RegExp, String
	with predefined WebScriptBuiltinFunction for methods like length, size etc.
	
	*/
		}
	return self;
}

+ (BOOL) throwException:(NSString *) message;
{
	[[NSException exceptionWithName:WebScriptException reason:message userInfo:nil] raise];
	return NO;
}

- (id) callWebScriptMethod:(NSString *) name withArguments:(NSArray *) args;
{
	return [[_GET(self, name) _getValue] _call:self arguments:args];
}

- (id) evaluateWebScript:(NSString *) script;
{ // evaluate for given node as the global object - is this also the eval("") method?
	// couldn't we use [self callWebScriptMethod:@"eval" withArguments:[NSArray arrayWithObject:script]];
	id r=nil;
	// if(disabled by WebPrefs) return nil;
	NS_DURING
		{
			WebScriptContext context;
			NSScanner *sc=[NSScanner scannerWithString:script];
#if 1
		NSLog(@"parsing script");
#endif
			r=[_WebScriptTreeNode _programWithScanner:sc block:NO];
#if 1
			NSLog(@"script=%@", r);
#endif
#if 1	// can be disabled to test if the parser is working well
			context.global=self;
			context.this=self;
			context.nextContext=NULL;	// start of chain
			r=[r _evaluate:&context];	// evaluate with self as global/this object
			r=[r _getValue];	// dereference if needed
#endif
		}
	NS_HANDLER
		r=[NSString stringWithFormat:@"<WebScript Exception: %@>", [localException reason]];
#if 1
		NSLog(@"web script exception %@", r);
		NSRunCriticalAlertPanel(@"WebScript", @"%@", @"Continue", nil, nil, r);	// show a popup
#endif
	NS_ENDHANDLER
	return r;
}

- (void) setException:(NSString *) message;
{
	[[NSException exceptionWithName:WebScriptException reason:message userInfo:[NSDictionary dictionaryWithObject:self forKey:@"this"]] raise];
}

- (NSString *) stringRepresentation;
{
	// should we format an array or object in JavaScript language?
	return [self description];
}

- (void) setWebScriptValueAtIndex:(unsigned int) index value:(id) val;
{
	NIMP;	// not available for generic object
	_PUT(self, ([NSString stringWithFormat:@"%u", index]), val);
}

- (id) webScriptValueAtIndex:(unsigned int) index;
{
	return NIMP;	// not available for generic object
	return _GET(self, ([NSString stringWithFormat:@"%u", index]));
}

- (void) removeWebScriptKey:(NSString *) key;
{
	NIMP;	// not for generic object
}

#if SIMPLY_INHERIT
- (void) setValue:(id) value forKey:(NSString *) key;
{ // KVC setter
	[super setValue:value forKey:key];
}

- (id) valueForKey:(NSString *) key;
{ // KVC getter
	return [super valueForKey:key];
}
#endif

- (id) valueForUndefinedKey:(NSString *)key
{
	return nil;
	// should be...
	// but this raises many problems since we sometimes assume in _layout that nil is returned if a property does not exist
	return [WebUndefined undefined];
}

@end

@implementation NSObject (WebScripting)

// NIMP - we don't do that until we need it and understand the security implications (if a webscript can access any Cocoa class and method)
// it appears that it is Full-WebKits way of bridging Cocoa objects to the JavaScript execution space

+ (BOOL) isKeyExcludedFromWebScript:(const char *) name; { return YES; }
+ (BOOL) isSelectorExcludedFromWebScript:(SEL) sel; { return YES; }
+ (NSString *) webScriptNameForKey:(const char *) name; { return @"?"; }
+ (NSString *) webScriptNameForSelector:(SEL) sel; { return @"?"; }
- (void) finalizeForWebScript; { return; }
- (id) invokeDefaultMethodWithArguments:(NSArray *) args; { return NIMP; }
- (id) invokeUndefinedMethodFromWebScript:(NSString *) name
														withArguments:(NSArray *) args; { return NIMP; }

@end

@implementation WebUndefined

+ (id) _alloc; { return [super alloc]; }
+ (id) alloc; { return NIMP; }	// don't call explicitly...

+ (WebUndefined *) undefined
{ // constant like NSNull but used by WebScript
	static WebUndefined *undef=nil;
	if(!undef)
		undef=[[self _alloc] init];
	return undef;
}

- (NSString *) description;
{
	return @"undefined";
}

@end