root/trunk/Views/JVStyleView.m

#import "JVStyleView.h"
#import "JVMarkedScroller.h"
#import "JVChatTranscript.h"
#import "JVChatMessage.h"
#import "JVStyle.h"
#import "JVEmoticonSet.h"

#import <objc/objc-runtime.h>

NSString *JVStyleViewDidClearNotification = @"JVStyleViewDidClearNotification";
NSString *JVStyleViewDidChangeStylesNotification = @"JVStyleViewDidChangeStylesNotification";

@interface WebCoreCache
+ (void) empty;
@end

#pragma mark -

@interface WebCache
+ (void) empty;
@end

#pragma mark -

@interface WebView (WebViewLeopard)
- (void) setDrawsBackground:(BOOL) draws; // supported in 10.3.9/Tiger
- (BOOL) drawsBackground; // supported in 10.3.9/Tiger
- (void) setBackgroundColor:(NSColor *) color; // new in Safari 3/Leopard
- (void) setProhibitsMainFrameScrolling:(BOOL) prohibit; // new in Safari 3/Leopard
- (WebFrame *) selectedFrame;
@end

#pragma mark -

@interface WebView (WebViewPrivate)
- (WebFrame *) _frameForCurrentSelection;
@end

#pragma mark -

@interface DOMHTMLElement (DOMHTMLElementLeopard)
- (int) offsetTop;
- (int) offsetHeight;
- (int) scrollHeight;
@end

#pragma mark -

@interface NSScrollView (NSScrollViewWebKitPrivate)
- (void) setAllowsHorizontalScrolling:(BOOL) allow;
@end

#pragma mark -

@interface DOMHTMLElement (DOMHTMLElementExtras)
- (unsigned) childElementLength;
- (DOMNode *) childElementAtIndex:(unsigned) index;
- (int) integerForDOMProperty:(NSString *) property;
- (void) setInteger:(int) value forDOMProperty:(NSString *) property;
@end

#pragma mark -

@implementation DOMHTMLElement (DOMHTMLElementExtras)
- (unsigned) childElementLength {
        unsigned length = 0;

        DOMNode *node = [self firstChild];
        while (node) {
                if( [node nodeType] == DOM_ELEMENT_NODE ) ++length;
                node = [node nextSibling];
        }

        return length;
}

- (DOMNode *) childElementAtIndex:(unsigned) index {
        unsigned count = 0;
        DOMNode *node = [self firstChild];
        while (node) {
                if( [node nodeType] == DOM_ELEMENT_NODE && count++ == index )
                        return node;
                node = [node nextSibling];
        }

        return nil;
}

- (int) integerForDOMProperty:(NSString *) property {
        SEL selector = NSSelectorFromString( property );
        if( [self respondsToSelector:selector] )
                return ((int(*)(id, SEL))objc_msgSend)(self, selector);
        NSNumber *value = [self valueForKey:property];
        if( [value isKindOfClass:[NSNumber class]] )
                return [value intValue];
        return 0;
}

- (void) setInteger:(int) value forDOMProperty:(NSString *) property {
        SEL selector = NSSelectorFromString( [@"set" stringByAppendingString:[property capitalizedString]] );
        if( [self respondsToSelector:selector] ) {
                ((void(*)(id, SEL, int))objc_msgSend)(self, selector, value);
        } else {
                NSNumber *number = [NSNumber numberWithInt:value];
                [self setValue:number forKey:property];
        }
}
@end

#pragma mark -

@interface JVStyleView (JVStyleViewPrivate)
- (void) _resetDisplay;
- (void) _switchStyle;
- (void) _appendMessage:(NSString *) message;
- (void) _prependMessages:(NSString *) messages;
- (void) _styleError;
- (NSString *) _contentHTMLWithBody:(NSString *) html;
- (NSURL *) _baseURL;
- (unsigned) _visibleMessageCount;
- (int) _locationOfMessage:(JVChatMessage *) message;
- (int) _locationOfElementAtIndex:(unsigned) index;
- (void) _setupMarkedScroller;
@end

#pragma mark -

@implementation JVStyleView
- (id) initWithCoder:(NSCoder *) coder {
        if( ( self = [super initWithCoder:coder] ) ) {
                _switchingStyles = NO;
                _forwarding = NO;
                _ready = NO;
                _contentFrameReady = NO;
                _requiresFullMessage = YES;
                _scrollbackLimit = 600;
                _transcript = nil;
                _style = nil;
                _styleVariant = nil;
                _styleParameters = [[NSMutableDictionary dictionary] retain];
                _emoticons = nil;
                _domDocument = nil;
                nextTextView = nil;
        }

        return self;
}

- (void) awakeFromNib {
        [self setFrameLoadDelegate:self];
        if( [self respondsToSelector:@selector(setProhibitsMainFrameScrolling:)] )
                [self setProhibitsMainFrameScrolling:YES];
        [self performSelector:@selector( _reallyAwakeFromNib ) withObject:nil afterDelay:0.];
}

- (void) dealloc {
        [[NSNotificationCenter defaultCenter] removeObserver:self name:JVStyleVariantChangedNotification object:nil];

        [nextTextView release];
        [_transcript release];
        [_style release];
        [_styleVariant release];
        [_styleParameters release];
        [_emoticons release];
        [_mainDocument release];
        [_domDocument release];
        [_body release];
        [_bodyTemplate release];

        nextTextView = nil;
        _transcript = nil;
        _style = nil;
        _styleVariant = nil;
        _styleParameters = nil;
        _emoticons = nil;
        _mainDocument = nil;
        _domDocument = nil;
        _body = nil;
        _bodyTemplate = nil;

        [super dealloc];
}

#pragma mark -

- (void) forwardSelector:(SEL) selector withObject:(id) object {
        if( [self nextTextView] ) {
                [[self window] makeFirstResponder:[self nextTextView]];
                [[self nextTextView] tryToPerform:selector with:object];
        }
}

#pragma mark -

- (void) keyDown:(NSEvent *) event {
        if( _forwarding ) return;
        _forwarding = YES;
        [self forwardSelector:@selector( keyDown: ) withObject:event];
        _forwarding = NO;
}

- (void) pasteAsPlainText:(id) sender {
        if( _forwarding ) return;
        _forwarding = YES;
        [self forwardSelector:@selector( pasteAsPlainText: ) withObject:sender];
        _forwarding = NO;
}

- (void) pasteAsRichText:(id) sender {
        if( _forwarding ) return;
        _forwarding = YES;
        [self forwardSelector:@selector( pasteAsRichText: ) withObject:sender];
        _forwarding = NO;
}

#pragma mark -

- (NSTextView *) nextTextView {
        return nextTextView;
}

- (void) setNextTextView:(NSTextView *) textView {
        [nextTextView autorelease];
        nextTextView = [textView retain];
}

#pragma mark -

- (void) setTranscript:(JVChatTranscript *) transcript {
        [_transcript autorelease];
        _transcript = [transcript retain];
}

- (JVChatTranscript *) transcript {
        return _transcript;
}

#pragma mark -

- (void) setStyle:(JVStyle *) style {
        [self setStyle:style withVariant:[style defaultVariantName]];
}

- (void) setStyle:(JVStyle *) style withVariant:(NSString *) variant {
        if( [style isEqualTo:[self style]] ) {
                [self setStyleVariant:variant];
                return;
        }

        [_style autorelease];
        _style = [style retain];

        [_styleVariant autorelease];
        _styleVariant = [variant copyWithZone:[self zone]];

        // add single-quotes so that these are not interpreted as XPath expressions  
        [_styleParameters setObject:@"'/tmp/'" forKey:@"buddyIconDirectory"];  
        [_styleParameters setObject:@"'.tif'" forKey:@"buddyIconExtension"];

        NSString *timeFormatParameter = [NSString stringWithFormat:@"'%@'", [[NSUserDefaults standardUserDefaults] stringForKey:NSTimeFormatString]];
        [_styleParameters setObject:timeFormatParameter forKey:@"timeFormat"];

        [[NSNotificationCenter defaultCenter] removeObserver:self name:JVStyleVariantChangedNotification object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector( _styleVariantChanged: ) name:JVStyleVariantChangedNotification object:style];

        _switchingStyles = YES;
        _requiresFullMessage = YES;

        if( ! _ready ) return;

        [self _resetDisplay];
}

- (JVStyle *) style {
        return _style;
}

#pragma mark -

- (void) setStyleVariant:(NSString *) variant {
        [_styleVariant autorelease];
        _styleVariant = [variant copyWithZone:[self zone]];

        if( _contentFrameReady ) {
                if( NSClassFromString( @"WebCoreCache" ) )
                        [NSClassFromString( @"WebCoreCache" ) empty];
                else if( NSClassFromString( @"WebCache" ) )
                        [NSClassFromString( @"WebCache" ) empty];

                NSString *styleSheetLocation = [[[self style] variantStyleSheetLocationWithName:_styleVariant] absoluteString];
                DOMHTMLLinkElement *element = (DOMHTMLLinkElement *)[_domDocument getElementById:@"variantStyle"];
                if( ! styleSheetLocation ) [element setHref:@""];
                else [element setHref:styleSheetLocation];

                [self performSelector:@selector( _checkForTransparantStyle ) withObject:nil afterDelay:0.];
        } else {
                [self performSelector:_cmd withObject:variant afterDelay:0.5];
        }
}

- (NSString *) styleVariant {
        return _styleVariant;
}

#pragma mark -

- (void) setBodyTemplate:(NSString *) bodyTemplate {
        [_bodyTemplate autorelease];
        _bodyTemplate = [bodyTemplate retain];
}

- (NSString *) bodyTemplate {
        return _bodyTemplate;
}

#pragma mark -

- (void) setStyleParameters:(NSDictionary *) parameters {
        id old = _styleParameters;
        _styleParameters = [parameters mutableCopyWithZone:[self zone]];
        [old release];
}

- (NSDictionary *) styleParameters {
        return [NSDictionary dictionaryWithDictionary:_styleParameters];
}

#pragma mark -

- (void) setEmoticons:(JVEmoticonSet *) emoticons {
        [_emoticons autorelease];
        _emoticons = [emoticons retain];

        if( _contentFrameReady ) {
                if( NSClassFromString( @"WebCoreCache" ) )
                        [NSClassFromString( @"WebCoreCache" ) empty];
                else if( NSClassFromString( @"WebCache" ) )
                        [NSClassFromString( @"WebCache" ) empty];

                NSString *styleSheetLocation = [[[self emoticons] styleSheetLocation] absoluteString];
                DOMHTMLLinkElement *element = (DOMHTMLLinkElement *)[_domDocument getElementById:@"emoticonStyle"];
                if( ! styleSheetLocation ) [element setHref:@""];
                else [element setHref:styleSheetLocation];
        } else {
                [self performSelector:_cmd withObject:emoticons afterDelay:0.5];
        }
}

- (JVEmoticonSet *) emoticons {
        return _emoticons;
}

#pragma mark -

- (void) setScrollbackLimit:(unsigned long) limit {
        _scrollbackLimit = limit;
}

- (unsigned long) scrollbackLimit {
        return _scrollbackLimit;
}

#pragma mark -

- (void) reloadCurrentStyle {
        _switchingStyles = YES;
        _requiresFullMessage = YES;
        _rememberScrollPosition = YES;

        if( NSClassFromString( @"WebCoreCache" ) )
                [NSClassFromString( @"WebCoreCache" ) empty];
        else if( NSClassFromString( @"WebCache" ) )
                [NSClassFromString( @"WebCache" ) empty];

        [self _resetDisplay];
}

- (void) clear {
        _switchingStyles = NO;
        _requiresFullMessage = YES;
        [self _resetDisplay];
}

- (void) mark {
        if( _contentFrameReady ) {
                DOMHTMLElement *elt = (DOMHTMLElement *)[_domDocument getElementById:@"mark"];
                if( elt ) [[elt parentNode] removeChild:elt];
                elt = (DOMHTMLElement *)[_domDocument createElement:@"hr"];
                [elt setAttribute:@"id" :@"mark"];
                [_body appendChild:elt];
                [self scrollToBottom];

                int location = [elt integerForDOMProperty:@"offsetTop"];

                JVMarkedScroller *scroller = [self verticalMarkedScroller];
                [scroller removeMarkWithIdentifier:@"mark"];
                [scroller addMarkAt:location withIdentifier:@"mark" withColor:[NSColor redColor]];

                _requiresFullMessage = YES;
        } else {
                [self performSelector:_cmd withObject:nil afterDelay:0.5];
        }
}

#pragma mark -

- (void) addBanner:(NSString *) name {
        if( ! _mainFrameReady ) {
                [self performSelector:_cmd withObject:name afterDelay:0.];
                return;
        }

        NSString *shell = [NSString stringWithContentsOfFile:[[NSBundle mainBundle] pathForResource:name ofType:@"html"] encoding:NSUTF8StringEncoding error:NULL];

        DOMHTMLElement *element = (DOMHTMLElement *)[_mainDocument createElement:@"div"];
        [element setClassName:@"banner"];
        if( [shell length] ) [element setInnerHTML:shell];

        [[_mainDocument body] insertBefore:element :[[_mainDocument body] firstChild]];
}

#pragma mark -

- (BOOL) appendChatMessage:(JVChatMessage *) message {
        if( ! _contentFrameReady ) return YES; // don't schedule this to fire later since the transcript will be processed

        if( _requiresFullMessage ) {
                DOMHTMLElement *replaceElement = (DOMHTMLElement *)[_domDocument getElementById:@"consecutiveInsert"];
                if( replaceElement ) _requiresFullMessage = NO; // a full message was assumed, but we can do a consecutive one
        }

        unsigned consecutiveOffset = [message consecutiveOffset];
        NSString *result = nil;

        if( _requiresFullMessage && consecutiveOffset > 0 ) {
                NSArray *elements = [[NSArray allocWithZone:nil] initWithObjects:message, nil];
                result = [[self style] transformChatTranscriptElements:elements withParameters:_styleParameters];
                [elements release];
        } else {
                if( ! _requiresFullMessage && consecutiveOffset > 0 )
                        [_styleParameters setObject:@"'yes'" forKey:@"consecutiveMessage"];
                result = [[self style] transformChatMessage:message withParameters:_styleParameters];
                [_styleParameters removeObjectForKey:@"consecutiveMessage"];
        }

        if( [result length] ) {
                [self _appendMessage:result];
                _requiresFullMessage = NO;
        }

        return ( [result length] ? YES : NO );
}

- (BOOL) appendChatTranscriptElement:(id <JVChatTranscriptElement>) element {
        if( ! _contentFrameReady ) return YES; // don't schedule this to fire later since the transcript will be processed

        NSString *result = [[self style] transformChatTranscriptElement:element withParameters:_styleParameters];

        if( [result length] ) [self _appendMessage:result];

        return ( [result length] ? YES : NO );
}

#pragma mark -

- (void) highlightMessage:(JVChatMessage *) message {
/*      DOMHTMLElement *element = (DOMHTMLElement *)[_domDocument getElementById:[message messageIdentifier]];
        NSString *class = [element className];
        if( [[element className] rangeOfString:@"searchHighlight"].location != NSNotFound ) return;
        if( [class length] ) [element setClassName:[class stringByAppendingString:@" searchHighlight"]];
        else [element setClassName:@"searchHighlight"];
*/}

- (void) clearHighlightForMessage:(JVChatMessage *) message {
/*      DOMHTMLElement *element = (DOMHTMLElement *)[_domDocument getElementById:[message messageIdentifier]];
        NSMutableString *class = [[[element className] mutableCopy] autorelease];
        [class replaceOccurrencesOfString:@"searchHighlight" withString:@"" options:NSLiteralSearch range:NSMakeRange( 0, [class length] )];
        [element setClassName:class];
*/}

- (void) clearAllMessageHighlights {
//      [[self windowScriptObject] callWebScriptMethod:@"resetHighlightMessage" withArguments:[NSArray arrayWithObject:[NSNull null]]];
}

#pragma mark -

- (void) highlightString:(NSString *) string inMessage:(JVChatMessage *) message {
        [[self windowScriptObject] callWebScriptMethod:@"searchHighlight" withArguments:[NSArray arrayWithObjects:[message messageIdentifier], string, nil]];
}

- (void) clearStringHighlightsForMessage:(JVChatMessage *) message {
        [[self windowScriptObject] callWebScriptMethod:@"resetSearchHighlight" withArguments:[NSArray arrayWithObject:[message messageIdentifier]]];
}

- (void) clearAllStringHighlights {
        [[self windowScriptObject] callWebScriptMethod:@"resetSearchHighlight" withArguments:[NSArray arrayWithObject:[NSNull null]]];
}

#pragma mark -

- (void) markScrollbarForMessage:(JVChatMessage *) message {
        if( _switchingStyles || ! _contentFrameReady ) {
                [self performSelector:_cmd withObject:message afterDelay:0.5];
                return;
        }

        int loc = [self _locationOfMessage:message];
        if( loc != NSNotFound ) [[self verticalMarkedScroller] addMarkAt:loc];
}

- (void) markScrollbarForMessage:(JVChatMessage *) message usingMarkIdentifier:(NSString *) identifier andColor:(NSColor *) color {
        if( _switchingStyles || ! _contentFrameReady ) return; // can't queue, too many args. NSInvocation?

        int loc = [self _locationOfMessage:message];
        if( loc != NSNotFound ) [[self verticalMarkedScroller] addMarkAt:loc withIdentifier:identifier withColor:color];
}

- (void) markScrollbarForMessages:(NSArray *) messages {
        if( _switchingStyles || ! _contentFrameReady ) {
                [self performSelector:_cmd withObject:messages afterDelay:0.5];
                return;
        }

        JVMarkedScroller *scroller = [self verticalMarkedScroller];
        NSEnumerator *enumerator = [messages objectEnumerator];
        JVChatMessage *message = nil;

        while( ( message = [enumerator nextObject] ) ) {
                int loc = [self _locationOfMessage:message];
                if( loc != NSNotFound ) [scroller addMarkAt:loc];
        }
}

#pragma mark -

- (void) clearScrollbarMarks {
        JVMarkedScroller *scroller = [self verticalMarkedScroller];
        [scroller removeAllMarks];
        [scroller removeAllShadedAreas];
}

- (void) clearScrollbarMarksWithIdentifier:(NSString *) identifier {
        [[self verticalMarkedScroller] removeMarkWithIdentifier:identifier];
}

#pragma mark -

- (void) webView:(WebView *) sender didFinishLoadForFrame:(WebFrame *) frame {
        if( frame == [self mainFrame] ) {
                _mainFrameReady = YES;

                [_mainDocument autorelease];
                _mainDocument = (DOMHTMLDocument *)[[frame DOMDocument] retain];

                WebFrame *contentFrame = [[self mainFrame] findFrameNamed:@"content"];
                [contentFrame loadHTMLString:[self _contentHTMLWithBody:@""] baseURL:[self _baseURL]];
        } else if( _mainFrameReady ) {
                if( [[[[[frame dataSource] response] URL] absoluteString] isEqualToString:@"about:blank"] ) {
                        // this was a false content frame load, try again
                        [frame loadHTMLString:[self _contentHTMLWithBody:@""] baseURL:[self _baseURL]];
                        return;
                }

                [self performSelector:@selector( _contentFrameIsReady ) withObject:nil afterDelay:0.];
        }
}

- (IBAction) copySelectionToFindPboard:(id) sender {
        WebFrame *frame = nil;
        if( [self respondsToSelector:@selector( selectedFrame )] )
                frame = [self selectedFrame];
        else if( [self respondsToSelector:@selector( _frameForCurrentSelection )] )
                frame = [self _frameForCurrentSelection];

        if( ! frame ) return;

        NSString *selectedString = [(id <WebDocumentText>)[[frame frameView] documentView] selectedString];

        if( [selectedString length] ) {
                NSPasteboard *pboard = [NSPasteboard pasteboardWithName:NSFindPboard];
                [pboard declareTypes:[NSArray arrayWithObject:NSStringPboardType] owner:nil];
                [pboard setString:selectedString forType:NSStringPboardType];
        }
}

- (void) drawRect:(NSRect) rect {
        if( ! [self drawsBackground] ) {
                [[NSColor clearColor] set];
                NSRectFill( rect ); // allows poking holes in the window with rgba background colors
        }

        [super drawRect:rect];
}

#pragma mark -
#pragma mark Highlight/Message Jumping

- (JVMarkedScroller *) verticalMarkedScroller { 
        WebFrame *contentFrame = [[self mainFrame] findFrameNamed:@"content"];
        NSScrollView *scrollView = [[[contentFrame frameView] documentView] enclosingScrollView]; 
        JVMarkedScroller *scroller = (JVMarkedScroller *)[scrollView verticalScroller]; 
        if( scroller && ! [scroller isMemberOfClass:[JVMarkedScroller class]] ) { 
                [self _setupMarkedScroller]; 
                scroller = (JVMarkedScroller *)[scrollView verticalScroller]; 
                if( scroller && ! [scroller isMemberOfClass:[JVMarkedScroller class]] ) 
                        return nil; // not sure, but somthing is wrong 
        } 

        return scroller; 
}

- (IBAction) jumpToMark:(id) sender {
    [[self verticalMarkedScroller] jumpToMarkWithIdentifier:@"mark"];
}

- (IBAction) jumpToPreviousHighlight:(id) sender {
    [[self verticalMarkedScroller] jumpToPreviousMark:sender];
}

- (IBAction) jumpToNextHighlight:(id) sender {
    [[self verticalMarkedScroller] jumpToNextMark:sender];
}

- (void) jumpToMessage:(JVChatMessage *) message {
        unsigned loc = [self _locationOfMessage:message];
        if( loc != NSNotFound ) {
                JVMarkedScroller *scroller = [self verticalMarkedScroller];
                int shift = [scroller shiftAmountToCenterAlign];
                [scroller setLocationOfCurrentMark:loc];

                [[_domDocument body] setInteger:( loc - shift ) forDOMProperty:@"scrollTop"];
        }
}

- (void) scrollToBottom {
        if( ! _contentFrameReady ) {
                [self performSelector:_cmd withObject:nil afterDelay:0.5];
                return;
        }

        DOMHTMLElement *body = [_domDocument body];
        [body setInteger:[body integerForDOMProperty:@"scrollHeight"] forDOMProperty:@"scrollTop"];
}

- (BOOL) scrolledNearBottom {
        WebFrame *contentFrame = [[self mainFrame] findFrameNamed:@"content"];
        DOMHTMLElement *contentFrameElement = [contentFrame frameElement];
        int frameHeight = [contentFrameElement integerForDOMProperty:@"offsetHeight"];

        DOMHTMLElement *body = [_domDocument body];
        int scrollHeight = [body integerForDOMProperty:@"scrollHeight"];
        int scrollTop = [body integerForDOMProperty:@"scrollTop"];

        // check if we are near the bottom 15 pixels of the chat area
        return ( ( frameHeight + scrollTop ) >= ( scrollHeight - 15 ) );
}
@end

#pragma mark -

@implementation JVStyleView (JVStyleViewPrivate)
- (void) _checkForTransparantStyle {
        DOMCSSStyleDeclaration *style = [self computedStyleForElement:_body pseudoElement:nil];
        DOMCSSValue *value = [style getPropertyCSSValue:@"background-color"];
        BOOL transparent = ( value && [[value cssText] rangeOfString:@"rgba"].location != NSNotFound );

        if( [self respondsToSelector:@selector(setBackgroundColor:)] ) {
                if( transparent ) [self setBackgroundColor:[NSColor clearColor]]; // allows rgba backgrounds to see through to the Desktop
                else [self setBackgroundColor:[NSColor whiteColor]];
        } else {
                if( transparent ) [self setDrawsBackground:NO]; // allows rgba backgrounds to see through to the Desktop
                else [self setDrawsBackground:YES];
        }
}

- (void) _contentFrameIsReady {
        WebFrame *contentFrame = [[self mainFrame] findFrameNamed:@"content"];

        id old = _domDocument;
        _domDocument = (DOMHTMLDocument *)[[contentFrame DOMDocument] retain];
        [old release];

        old = _body;
        _body = (DOMHTMLElement *)[[_domDocument getElementById:@"contents"] retain];
        if( ! _body ) _body = (DOMHTMLElement *)[[_domDocument body] retain];
        [old release];

        if( ! _body ) {
                // try again soon, the DOM is not ready yet
                [self performSelector:@selector( _contentFrameIsReady ) withObject:nil afterDelay:0.5];
                return;
        }

        [self _checkForTransparantStyle];

        [self setPreferencesIdentifier:[[self style] identifier]];

        [self clearScrollbarMarks];

        if( [[self window] isFlushWindowDisabled] )
                [[self window] enableFlushWindow];

        _contentFrameReady = YES;
        [[NSNotificationCenter defaultCenter] postNotificationName:JVStyleViewDidClearNotification object:self];
        if( _switchingStyles )
                [NSThread detachNewThreadSelector:@selector( _switchStyle ) toTarget:self withObject:nil];
}

- (void) _reallyAwakeFromNib {
        _ready = YES;
        [self _resetDisplay];
}

- (void) _resetDisplay {
        [[self class] cancelPreviousPerformRequestsWithTarget:self selector:_cmd object:nil];

        [self stopLoading:nil];
        [self clearScrollbarMarks];

        _contentFrameReady = NO;
        if( _rememberScrollPosition ) {
                _lastScrollPosition = [[_domDocument body] integerForDOMProperty:@"scrollTop"];
        } else _lastScrollPosition = 0;

        if( ! [[self window] isFlushWindowDisabled] )
                [[self window] disableFlushWindow];

        if( _mainFrameReady ) {
                WebFrame *contentFrame = [[self mainFrame] findFrameNamed:@"content"];
                [contentFrame loadHTMLString:[self _contentHTMLWithBody:@""] baseURL:[self _baseURL]];
        } else {
                NSString *path = [[NSBundle mainBundle] pathForResource:@"base" ofType:@"html"];
                NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL fileURLWithPath:path] cachePolicy:NSURLRequestReloadIgnoringCacheData timeoutInterval:5.];
                [[self mainFrame] loadRequest:request];
        }
}

- (void) _switchStyle {
        NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

        [NSThread setThreadPriority:0.25];

        [NSThread sleepUntilDate:[NSDate dateWithTimeIntervalSinceNow:0.00025]]; // wait, WebKit might not be ready.

        JVStyle *style = [[self style] retain];
        JVChatTranscript *transcript = [[self transcript] retain];
        NSMutableArray *highlightedMsgs = [[NSMutableArray allocWithZone:nil] initWithCapacity:( [self scrollbackLimit] / 8 )];
        NSMutableDictionary *parameters = [[NSMutableDictionary allocWithZone:nil] initWithDictionary:_styleParameters copyItems:NO];
        unsigned long elementCount = [transcript elementCount];

        [parameters setObject:@"'yes'" forKey:@"bulkTransform"];

        for( unsigned long i = elementCount; i > ( elementCount - MIN( [self scrollbackLimit], elementCount ) ); i -= MIN( 25u, i ) ) {
                NSArray *elements = [transcript elementsInRange:NSMakeRange( i - MIN( 25u, i ), MIN( 25u, i ) )];

                id element = nil;
                NSEnumerator *enumerator = [elements objectEnumerator];
                while( ( element = [enumerator nextObject] ) )
                        if( [element isKindOfClass:[JVChatMessage class]] && [element isHighlighted] )
                                [highlightedMsgs addObject:element];

                NSString *result = [style transformChatTranscriptElements:elements withParameters:parameters];

                if( [self style] != style ) goto quickEnd;
                if( result ) {
                        [self performSelectorOnMainThread:@selector( _prependMessages: ) withObject:result waitUntilDone:YES];
                        [NSThread sleepUntilDate:[NSDate dateWithTimeIntervalSinceNow:1.]]; // give time to other threads
                }
        }

        _switchingStyles = NO;
        [self performSelectorOnMainThread:@selector( markScrollbarForMessages: ) withObject:highlightedMsgs waitUntilDone:YES];

quickEnd:
        [self performSelectorOnMainThread:@selector( _switchingStyleFinished: ) withObject:nil waitUntilDone:YES];

        NSNotification *note = [NSNotification notificationWithName:JVStyleViewDidChangeStylesNotification object:self userInfo:nil];
        [[NSNotificationCenter defaultCenter] postNotificationOnMainThread:note];

        [highlightedMsgs release];
        [parameters release];
        [style release];
        [transcript release];
        [pool release];
}

- (void) _switchingStyleFinished:(id) sender {
        _switchingStyles = NO;

        if( _rememberScrollPosition ) {
                _rememberScrollPosition = NO;
                [[_domDocument body] setInteger:_lastScrollPosition forDOMProperty:@"scrollTop"];
        }
}

- (void) _appendMessage:(NSString *) message {
        if( ! _body ) return;

        unsigned messageCount = [self _visibleMessageCount] + 1;
        unsigned scrollbackLimit = [self scrollbackLimit];
        JVMarkedScroller *scroller = [self verticalMarkedScroller];
        BOOL consecutive = ( [message rangeOfString:@"<?message type=\"consecutive\"?>"].location != NSNotFound );
        if( ! consecutive ) consecutive = ( [message rangeOfString:@"<?message type=\"subsequent\"?>"].location != NSNotFound );

        // check if we are near the bottom of the chat area, and if we should scroll down later
        BOOL scrollToBottomNeeded = [self scrolledNearBottom];