/*

 * Copyright (C) 2008, 2009 Apple 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.

 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of

 *     its contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "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 OR ITS 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.

 */

#import "config.h"

#import "AccessibilityObjectWrapper.h"

#if HAVE(ACCESSIBILITY)

#import "AXObjectCache.h"

#import "AccessibilityARIAGridRow.h"

#import "AccessibilityListBox.h"

#import "AccessibilityList.h"

#import "AccessibilityRenderObject.h"

#import "AccessibilityTable.h"

#import "AccessibilityTableCell.h"

#import "AccessibilityTableRow.h"

#import "AccessibilityTableColumn.h"

#import "ColorMac.h"

#import "Frame.h"

#import "HTMLAnchorElement.h"

#import "HTMLAreaElement.h"

#import "HTMLFrameOwnerElement.h"

#import "HTMLImageElement.h"

#import "HTMLInputElement.h"

#import "HTMLTextAreaElement.h"

#import "LocalizedStrings.h"

#import "RenderTextControl.h"

#import "RenderView.h"

#import "RenderWidget.h"

#import "SelectionController.h"

#import "SimpleFontData.h"

#import "TextIterator.h"

#import "WebCoreFrameView.h"

#import "WebCoreObjCExtras.h"

#import "WebCoreViewFactory.h"

#import "htmlediting.h"

#import "visible_units.h"

using namespace WebCore;

using namespace HTMLNames;

using namespace std;

// Cell Tables

#ifndef NSAccessibilitySelectedCellsAttribute

#define NSAccessibilitySelectedCellsAttribute @"AXSelectedCells"

#endif

#ifndef NSAccessibilityVisibleCellsAttribute

#define NSAccessibilityVisibleCellsAttribute @"AXVisibleCells"

#endif

#ifndef NSAccessibilityRowHeaderUIElementsAttribute

#define NSAccessibilityRowHeaderUIElementsAttribute @"AXRowHeaderUIElements"

#endif

#ifndef NSAccessibilityRowIndexRangeAttribute

#define NSAccessibilityRowIndexRangeAttribute @"AXRowIndexRange"

#endif

#ifndef NSAccessibilityColumnIndexRangeAttribute

#define NSAccessibilityColumnIndexRangeAttribute @"AXColumnIndexRange"

#endif

#ifndef NSAccessibilityCellForColumnAndRowParameterizedAttribute

#define NSAccessibilityCellForColumnAndRowParameterizedAttribute @"AXCellForColumnAndRow"

#endif

#ifndef NSAccessibilityCellRole

#define NSAccessibilityCellRole @"AXCell"

#endif

// Lists

#ifndef NSAccessibilityContentListSubrole

#define NSAccessibilityContentListSubrole @"AXContentList"

#endif

#ifndef NSAccessibilityDefinitionListSubrole

#define NSAccessibilityDefinitionListSubrole @"AXDefinitionList"

#endif

// Miscellaneous

#ifndef NSAccessibilityBlockQuoteLevelAttribute

#define NSAccessibilityBlockQuoteLevelAttribute @"AXBlockQuoteLevel"

#endif

#ifndef NSAccessibilityAccessKeyAttribute

#define NSAccessibilityAccessKeyAttribute @"AXAccessKey"

#endif

#ifndef NSAccessibilityLanguageAttribute

#define NSAccessibilityLanguageAttribute @"AXLanguage"

#endif

#ifndef NSAccessibilityRequiredAttribute

#define NSAccessibilityRequiredAttribute @"AXRequired"

#endif

#ifndef NSAccessibilityOwnsAttribute

#define NSAccessibilityOwnsAttribute @"AXOwns"

#endif

#ifndef NSAccessibilityGrabbedAttribute

#define NSAccessibilityGrabbedAttribute @"AXGrabbed"

#endif

#ifndef NSAccessibilityDropEffectsAttribute

#define NSAccessibilityDropEffectsAttribute @"AXDropEffects"

#endif

#ifndef NSAccessibilityARIALiveAttribute

#define NSAccessibilityARIALiveAttribute @"AXARIALive"

#endif

#ifndef NSAccessibilityARIAAtomicAttribute

#define NSAccessibilityARIAAtomicAttribute @"AXARIAAtomic"

#endif

#ifndef NSAccessibilityARIARelevantAttribute

#define NSAccessibilityARIARelevantAttribute @"AXARIARelevant"

#endif

#ifndef NSAccessibilityARIABusyAttribute

#define NSAccessibilityARIABusyAttribute @"AXARIABusy"

#endif

#ifndef NSAccessibilityLoadingProgressAttribute

#define NSAccessibilityLoadingProgressAttribute @"AXLoadingProgress"

#endif

#ifndef NSAccessibilityHasPopupAttribute

#define NSAccessibilityHasPopupAttribute @"AXHasPopup"

#endif

#ifdef BUILDING_ON_TIGER

typedef unsigned NSUInteger;

#define NSAccessibilityValueDescriptionAttribute @"AXValueDescription"

#define NSAccessibilityTimelineSubrole @"AXTimeline"

#endif

@interface NSObject (WebKitAccessibilityArrayCategory)

- (NSUInteger)accessibilityIndexOfChild:(id)child;

- (NSUInteger)accessibilityArrayAttributeCount:(NSString *)attribute;

- (NSArray *)accessibilityArrayAttributeValues:(NSString *)attribute index:(NSUInteger)index maxCount:(NSUInteger)maxCount;

@end

@implementation AccessibilityObjectWrapper

- (id)initWithAccessibilityObject:(AccessibilityObject*)axObject

{

    [super init];

    m_object = axObject;

    return self;

}

- (void)unregisterUniqueIdForUIElement

{

    [[WebCoreViewFactory sharedFactory] unregisterUniqueIdForUIElement:self];

}

- (void)detach

{

    // Send unregisterUniqueIdForUIElement unconditionally because if it is

    // ever accidentally not done (via other bugs in our AX implementation) you

    // end up with a crash like <rdar://problem/4273149>.  It is safe and not

    // expensive to send even if the object is not registered.

    [self unregisterUniqueIdForUIElement];

    m_object = 0;

}

- (AccessibilityObject*)accessibilityObject

{

    return m_object;

}

- (NSView*)attachmentView

{

    ASSERT(m_object->isAttachment());

    Widget* widget = m_object->widgetForAttachmentView();

    if (!widget)

        return nil;

    return NSAccessibilityUnignoredDescendant(widget->platformWidget());

}

static WebCoreTextMarker* textMarkerForVisiblePosition(const VisiblePosition& visiblePos)

{

    TextMarkerData textMarkerData;

    AXObjectCache::textMarkerDataForVisiblePosition(textMarkerData, visiblePos);

    if (!textMarkerData.axID)

        return nil;

    return [[WebCoreViewFactory sharedFactory] textMarkerWithBytes:&textMarkerData length:sizeof(textMarkerData)];

}

static VisiblePosition visiblePositionForTextMarker(WebCoreTextMarker* textMarker)

{

    if (!textMarker)

        return VisiblePosition();

    TextMarkerData textMarkerData;

    if (![[WebCoreViewFactory sharedFactory] getBytes:&textMarkerData fromTextMarker:textMarker length:sizeof(textMarkerData)])

        return VisiblePosition();

    return AXObjectCache::visiblePositionForTextMarkerData(textMarkerData);

}

static VisiblePosition visiblePositionForStartOfTextMarkerRange(WebCoreTextMarkerRange* textMarkerRange)

{

    return visiblePositionForTextMarker([[WebCoreViewFactory sharedFactory] startOfTextMarkerRange:textMarkerRange]);

}

static VisiblePosition visiblePositionForEndOfTextMarkerRange(WebCoreTextMarkerRange* textMarkerRange)

{

    return visiblePositionForTextMarker([[WebCoreViewFactory sharedFactory] endOfTextMarkerRange:textMarkerRange]);

}

static WebCoreTextMarkerRange* textMarkerRangeFromMarkers(WebCoreTextMarker* textMarker1, WebCoreTextMarker* textMarker2)

{

    if (!textMarker1 || !textMarker2)

        return nil;

    return [[WebCoreViewFactory sharedFactory] textMarkerRangeWithStart:textMarker1 end:textMarker2];

}

static void AXAttributeStringSetFont(NSMutableAttributedString* attrString, NSString* attribute, NSFont* font, NSRange range)

{

    NSDictionary* dict;

    if (font) {

        dict = [NSDictionary dictionaryWithObjectsAndKeys:

            [font fontName]                             , NSAccessibilityFontNameKey,

            [font familyName]                           , NSAccessibilityFontFamilyKey,

            [font displayName]                          , NSAccessibilityVisibleNameKey,

            [NSNumber numberWithFloat:[font pointSize]] , NSAccessibilityFontSizeKey,

        nil];

        [attrString addAttribute:attribute value:dict range:range];

    } else

        [attrString removeAttribute:attribute range:range];

}

static CGColorRef CreateCGColorIfDifferent(NSColor* nsColor, CGColorRef existingColor)

{

    // get color information assuming NSDeviceRGBColorSpace 

    NSColor* rgbColor = [nsColor colorUsingColorSpaceName:NSDeviceRGBColorSpace];

    if (rgbColor == nil)

        rgbColor = [NSColor blackColor];

    CGFloat components[4];

    [rgbColor getRed:&components[0] green:&components[1] blue:&components[2] alpha:&components[3]];

    // create a new CGColorRef to return

    CGColorSpaceRef cgColorSpace = CGColorSpaceCreateDeviceRGB();

    CGColorRef cgColor = CGColorCreate(cgColorSpace, components);

    CGColorSpaceRelease(cgColorSpace);

    // check for match with existing color

    if (existingColor && CGColorEqualToColor(cgColor, existingColor)) {

        CGColorRelease(cgColor);

        cgColor = 0;

    }

    return cgColor;

}

static void AXAttributeStringSetColor(NSMutableAttributedString* attrString, NSString* attribute, NSColor* color, NSRange range)

{

    if (color) {

        CGColorRef existingColor = (CGColorRef) [attrString attribute:attribute atIndex:range.location effectiveRange:nil];

        CGColorRef cgColor = CreateCGColorIfDifferent(color, existingColor);

        if (cgColor) {

            [attrString addAttribute:attribute value:(id)cgColor range:range];

            CGColorRelease(cgColor);

        }

    } else

        [attrString removeAttribute:attribute range:range];

}

static void AXAttributeStringSetNumber(NSMutableAttributedString* attrString, NSString* attribute, NSNumber* number, NSRange range)

{

    if (number)

        [attrString addAttribute:attribute value:number range:range];

    else

        [attrString removeAttribute:attribute range:range];

}

static void AXAttributeStringSetStyle(NSMutableAttributedString* attrString, RenderObject* renderer, NSRange range)

{

    RenderStyle* style = renderer->style();

    // set basic font info

    AXAttributeStringSetFont(attrString, NSAccessibilityFontTextAttribute, style->font().primaryFont()->getNSFont(), range);

    // set basic colors

    AXAttributeStringSetColor(attrString, NSAccessibilityForegroundColorTextAttribute, nsColor(style->visitedDependentColor(CSSPropertyColor)), range);

    AXAttributeStringSetColor(attrString, NSAccessibilityBackgroundColorTextAttribute, nsColor(style->visitedDependentColor(CSSPropertyBackgroundColor)), range);

    // set super/sub scripting

    EVerticalAlign alignment = style->verticalAlign();

    if (alignment == SUB)

        AXAttributeStringSetNumber(attrString, NSAccessibilitySuperscriptTextAttribute, [NSNumber numberWithInt:(-1)], range);

    else if (alignment == SUPER)

        AXAttributeStringSetNumber(attrString, NSAccessibilitySuperscriptTextAttribute, [NSNumber numberWithInt:1], range);

    else

        [attrString removeAttribute:NSAccessibilitySuperscriptTextAttribute range:range];

    // set shadow

    if (style->textShadow())

        AXAttributeStringSetNumber(attrString, NSAccessibilityShadowTextAttribute, [NSNumber numberWithBool:YES], range);

    else

        [attrString removeAttribute:NSAccessibilityShadowTextAttribute range:range];

    // set underline and strikethrough

    int decor = style->textDecorationsInEffect();

    if ((decor & UNDERLINE) == 0) {

        [attrString removeAttribute:NSAccessibilityUnderlineTextAttribute range:range];

        [attrString removeAttribute:NSAccessibilityUnderlineColorTextAttribute range:range];

    }

    if ((decor & LINE_THROUGH) == 0) {

        [attrString removeAttribute:NSAccessibilityStrikethroughTextAttribute range:range];

        [attrString removeAttribute:NSAccessibilityStrikethroughColorTextAttribute range:range];

    }

    if ((decor & (UNDERLINE | LINE_THROUGH)) != 0) {

        // find colors using quirk mode approach (strict mode would use current

        // color for all but the root line box, which would use getTextDecorationColors)

        Color underline, overline, linethrough;

        renderer->getTextDecorationColors(decor, underline, overline, linethrough);

        if ((decor & UNDERLINE) != 0) {

            AXAttributeStringSetNumber(attrString, NSAccessibilityUnderlineTextAttribute, [NSNumber numberWithBool:YES], range);

            AXAttributeStringSetColor(attrString, NSAccessibilityUnderlineColorTextAttribute, nsColor(underline), range);

        }

        if ((decor & LINE_THROUGH) != 0) {

            AXAttributeStringSetNumber(attrString, NSAccessibilityStrikethroughTextAttribute, [NSNumber numberWithBool:YES], range);

            AXAttributeStringSetColor(attrString, NSAccessibilityStrikethroughColorTextAttribute, nsColor(linethrough), range);

        }

    }

}

static int blockquoteLevel(RenderObject* renderer)

{

    if (!renderer)

        return 0;

    int result = 0;

    for (Node* node = renderer->node(); node; node = node->parent()) {

        if (node->hasTagName(blockquoteTag))

            result += 1;

    }

    return result;

}

static void AXAttributeStringSetBlockquoteLevel(NSMutableAttributedString* attrString, RenderObject* renderer, NSRange range)

{

    int quoteLevel = blockquoteLevel(renderer);

    if (quoteLevel)

        [attrString addAttribute:NSAccessibilityBlockQuoteLevelAttribute value:[NSNumber numberWithInt:quoteLevel] range:range];

    else

        [attrString removeAttribute:NSAccessibilityBlockQuoteLevelAttribute range:range];

}

static void AXAttributeStringSetSpelling(NSMutableAttributedString* attrString, Node* node, int offset, NSRange range)

{

    Vector<DocumentMarker> markers = node->renderer()->document()->markersForNode(node);

    Vector<DocumentMarker>::iterator markerIt = markers.begin();

    unsigned endOffset = (unsigned)offset + range.length;

    for ( ; markerIt != markers.end(); markerIt++) {

        DocumentMarker marker = *markerIt;

        if (marker.type != DocumentMarker::Spelling)

            continue;

        if (marker.endOffset <= (unsigned)offset)

            continue;

        if (marker.startOffset > endOffset)

            break;

        // add misspelling attribute for the intersection of the marker and the range

        int rStart = range.location + (marker.startOffset - offset);

        int rLength = min(marker.endOffset, endOffset) - marker.startOffset;

        NSRange spellRange = NSMakeRange(rStart, rLength);

        AXAttributeStringSetNumber(attrString, NSAccessibilityMisspelledTextAttribute, [NSNumber numberWithBool:YES], spellRange);

        if (marker.endOffset > endOffset + 1)

            break;

    }

}

static void AXAttributeStringSetHeadingLevel(NSMutableAttributedString* attrString, RenderObject* renderer, NSRange range)

{

    if (!renderer)

        return;

    AccessibilityObject* parentObject = renderer->document()->axObjectCache()->getOrCreate(renderer->parent());

    int parentHeadingLevel = parentObject->headingLevel();

    if (parentHeadingLevel)

        [attrString addAttribute:@"AXHeadingLevel" value:[NSNumber numberWithInt:parentHeadingLevel] range:range];

    else

        [attrString removeAttribute:@"AXHeadingLevel" range:range];

}

static void AXAttributeStringSetElement(NSMutableAttributedString* attrString, NSString* attribute, AccessibilityObject* object, NSRange range)

{

    if (object && object->isAccessibilityRenderObject()) {

        // make a serializable AX object

        RenderObject* renderer = static_cast<AccessibilityRenderObject*>(object)->renderer();

        if (!renderer)

            return;

        Document* doc = renderer->document();

        if (!doc)

            return;

        AXObjectCache* cache = doc->axObjectCache();

        if (!cache)

            return;

        AXUIElementRef axElement = [[WebCoreViewFactory sharedFactory] AXUIElementForElement:object->wrapper()];

        if (axElement) {

            [attrString addAttribute:attribute value:(id)axElement range:range];

            CFRelease(axElement);

        }

    } else

        [attrString removeAttribute:attribute range:range];

}

static void AXAttributedStringAppendText(NSMutableAttributedString* attrString, Node* node, int offset, const UChar* chars, int length)

{

    // skip invisible text

    if (!node->renderer())

        return;

    // easier to calculate the range before appending the string

    NSRange attrStringRange = NSMakeRange([attrString length], length);

    // append the string from this node

    [[attrString mutableString] appendString:[NSString stringWithCharacters:chars length:length]];

    // add new attributes and remove irrelevant inherited ones

    // NOTE: color attributes are handled specially because -[NSMutableAttributedString addAttribute: value: range:] does not merge

    // identical colors.  Workaround is to not replace an existing color attribute if it matches what we are adding.  This also means

    // we cannot just pre-remove all inherited attributes on the appended string, so we have to remove the irrelevant ones individually.

    // remove inherited attachment from prior AXAttributedStringAppendReplaced

    [attrString removeAttribute:NSAccessibilityAttachmentTextAttribute range:attrStringRange];

    // set new attributes

    AXAttributeStringSetStyle(attrString, node->renderer(), attrStringRange);

    AXAttributeStringSetHeadingLevel(attrString, node->renderer(), attrStringRange);

    AXAttributeStringSetBlockquoteLevel(attrString, node->renderer(), attrStringRange);

    AXAttributeStringSetElement(attrString, NSAccessibilityLinkTextAttribute, AccessibilityObject::anchorElementForNode(node), attrStringRange);

    // do spelling last because it tends to break up the range

    AXAttributeStringSetSpelling(attrString, node, offset, attrStringRange);

}

static NSString* nsStringForReplacedNode(Node* replacedNode)

{

    // we should always be given a rendered node and a replaced node, but be safe

    // replaced nodes are either attachments (widgets) or images

    if (!replacedNode || !replacedNode->renderer() || !replacedNode->renderer()->isReplaced() || replacedNode->isTextNode()) {

        ASSERT_NOT_REACHED();

        return nil;

    }

    // create an AX object, but skip it if it is not supposed to be seen

    RefPtr<AccessibilityObject> obj = replacedNode->renderer()->document()->axObjectCache()->getOrCreate(replacedNode->renderer());

    if (obj->accessibilityIsIgnored())

        return nil;

    // use the attachmentCharacter to represent the replaced node

    const UniChar attachmentChar = NSAttachmentCharacter;

    return [NSString stringWithCharacters:&attachmentChar length:1];

}

- (NSAttributedString*)doAXAttributedStringForTextMarkerRange:(WebCoreTextMarkerRange*)textMarkerRange

{

    if (!m_object)

        return nil;

    // extract the start and end VisiblePosition

    VisiblePosition startVisiblePosition = visiblePositionForStartOfTextMarkerRange(textMarkerRange);

    if (startVisiblePosition.isNull())

        return nil;

    VisiblePosition endVisiblePosition = visiblePositionForEndOfTextMarkerRange(textMarkerRange);

    if (endVisiblePosition.isNull())

        return nil;

    VisiblePositionRange visiblePositionRange(startVisiblePosition, endVisiblePosition);

    // iterate over the range to build the AX attributed string

    NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] init];

    TextIterator it(makeRange(startVisiblePosition, endVisiblePosition).get());