/*

 * Copyright (C) 2005, 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. 

 * 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 <WebKit/WebNSViewExtras.h>

#import <WebKit/DOMExtensions.h>

#import <WebKit/WebDataSource.h>

#import <WebKit/WebFramePrivate.h>

#import <WebKit/WebFrameViewInternal.h>

#import <WebKit/WebNSImageExtras.h>

#import <WebKit/WebNSPasteboardExtras.h>

#import <WebKit/WebNSURLExtras.h>

#import <WebKit/WebView.h>

#define WebDragStartHysteresisX                 5.0f

#define WebDragStartHysteresisY                 5.0f

#define WebMaxDragImageSize                     NSMakeSize(400.0f, 400.0f)

#define WebMaxOriginalImageArea                 (1500.0f * 1500.0f)

#define WebDragIconRightInset                   7.0f

#define WebDragIconBottomInset                  3.0f

@implementation NSView (WebExtras)

- (NSView *)_web_superviewOfClass:(Class)class

{

    NSView *view = [self superview];

    while (view  && ![view isKindOfClass:class])

        view = [view superview];

    return view;

}

- (WebFrameView *)_web_parentWebFrameView

{

    return (WebFrameView *)[self _web_superviewOfClass:[WebFrameView class]];

}

// FIXME: Mail is the only client of _webView, remove this method once no versions of Mail need it.

- (WebView *)_webView

{

    return (WebView *)[self _web_superviewOfClass:[WebView class]];

}

/* Determine whether a mouse down should turn into a drag; started as copy of NSTableView code */

- (BOOL)_web_dragShouldBeginFromMouseDown:(NSEvent *)mouseDownEvent

                           withExpiration:(NSDate *)expiration

                              xHysteresis:(float)xHysteresis

                              yHysteresis:(float)yHysteresis

{

    NSEvent *nextEvent, *firstEvent, *dragEvent, *mouseUp;

    BOOL dragIt;

    if ([mouseDownEvent type] != NSLeftMouseDown) {

        return NO;

    }

    nextEvent = nil;

    firstEvent = nil;

    dragEvent = nil;

    mouseUp = nil;

    dragIt = NO;

    while ((nextEvent = [[self window] nextEventMatchingMask:(NSLeftMouseUpMask | NSLeftMouseDraggedMask)

                                                   untilDate:expiration

                                                      inMode:NSEventTrackingRunLoopMode

                                                     dequeue:YES]) != nil) {

        if (firstEvent == nil) {

            firstEvent = nextEvent;

        }

        if ([nextEvent type] == NSLeftMouseDragged) {

            float deltax = ABS([nextEvent locationInWindow].x - [mouseDownEvent locationInWindow].x);

            float deltay = ABS([nextEvent locationInWindow].y - [mouseDownEvent locationInWindow].y);

            dragEvent = nextEvent;

            if (deltax >= xHysteresis) {

                dragIt = YES;

                break;

            }

            if (deltay >= yHysteresis) {

                dragIt = YES;

                break;

            }

        } else if ([nextEvent type] == NSLeftMouseUp) {

            mouseUp = nextEvent;

            break;

        }

    }

    // Since we've been dequeuing the events (If we don't, we'll never see the mouse up...),

    // we need to push some of the events back on.  It makes sense to put the first and last

    // drag events and the mouse up if there was one.

    if (mouseUp != nil) {

        [NSApp postEvent:mouseUp atStart:YES];

    }

    if (dragEvent != nil) {

        [NSApp postEvent:dragEvent atStart:YES];

    }

    if (firstEvent != mouseUp && firstEvent != dragEvent) {

        [NSApp postEvent:firstEvent atStart:YES];

    }

    return dragIt;

}

- (BOOL)_web_dragShouldBeginFromMouseDown:(NSEvent *)mouseDownEvent

                           withExpiration:(NSDate *)expiration

{

    return [self _web_dragShouldBeginFromMouseDown:mouseDownEvent

                                    withExpiration:expiration

                                       xHysteresis:WebDragStartHysteresisX

                                       yHysteresis:WebDragStartHysteresisY];

}

- (NSDragOperation)_web_dragOperationForDraggingInfo:(id <NSDraggingInfo>)sender

{

    if (![NSApp modalWindow] && 

        ![[self window] attachedSheet] &&

        [sender draggingSource] != self &&

        [[sender draggingPasteboard] _web_bestURL]) {

        return NSDragOperationCopy;

    }

    return NSDragOperationNone;

}

- (void)_web_DragImageForElement:(DOMElement *)element

                         rect:(NSRect)rect

                        event:(NSEvent *)event

                   pasteboard:(NSPasteboard *)pasteboard 

                       source:(id)source

                       offset:(NSPoint *)dragImageOffset

{

    NSPoint mouseDownPoint = [self convertPoint:[event locationInWindow] fromView:nil];

    NSImage *dragImage;

    NSPoint origin;

    NSImage *image = [element image];

    if (image != nil && [image size].height * [image size].width <= WebMaxOriginalImageArea) {

        NSSize originalSize = rect.size;

        origin = rect.origin;

        dragImage = [[image copy] autorelease];

        [dragImage setScalesWhenResized:YES];

        [dragImage setSize:originalSize];

        [dragImage _web_scaleToMaxSize:WebMaxDragImageSize];

        NSSize newSize = [dragImage size];

        [dragImage _web_dissolveToFraction:WebDragImageAlpha];

        // Properly orient the drag image and orient it differently if it's smaller than the original

        origin.x = mouseDownPoint.x - (((mouseDownPoint.x - origin.x) / originalSize.width) * newSize.width);

        origin.y = origin.y + originalSize.height;

        origin.y = mouseDownPoint.y - (((mouseDownPoint.y - origin.y) / originalSize.height) * newSize.height);

    } else {

        // FIXME: This has been broken for a while.

        // There's no way to get the MIME type for the image from a DOM element.

        // The old code used WKGetPreferredExtensionForMIMEType([image MIMEType]);

        NSString *extension = @"";

        dragImage = [[NSWorkspace sharedWorkspace] iconForFileType:extension];

        NSSize offset = NSMakeSize([dragImage size].width - WebDragIconRightInset, -WebDragIconBottomInset);

        origin = NSMakePoint(mouseDownPoint.x - offset.width, mouseDownPoint.y - offset.height);

    }

    // This is the offset from the lower left corner of the image to the mouse location.  Because we

    // are a flipped view the calculation of Y is inverted.

    if (dragImageOffset) {

        dragImageOffset->x = mouseDownPoint.x - origin.x;

        dragImageOffset->y = origin.y - mouseDownPoint.y;

    }

    // Per kwebster, offset arg is ignored

    [self dragImage:dragImage at:origin offset:NSZeroSize event:event pasteboard:pasteboard source:source slideBack:YES];

}

- (BOOL)_web_firstResponderIsSelfOrDescendantView

{

    NSResponder *responder = [[self window] firstResponder];

    return (responder && 

           (responder == self || 

           ([responder isKindOfClass:[NSView class]] && [(NSView *)responder isDescendantOf:self])));

}

- (NSRect)_web_convertRect:(NSRect)aRect toView:(NSView *)aView

{

    // Converting to this view's window; let -convertRect:toView: handle it

    if (aView == nil)

        return [self convertRect:aRect toView:nil];

    // This view must be in a window.  Do whatever weird thing -convertRect:toView: does in this situation.

    NSWindow *thisWindow = [self window];

    if (!thisWindow)

        return [self convertRect:aRect toView:aView];

    // The other view must be in a window, too.

    NSWindow *otherWindow = [aView window];

    if (!otherWindow)

        return [self convertRect:aRect toView:aView];

    // Convert to this window's coordinates

    NSRect convertedRect = [self convertRect:aRect toView:nil];

    // Convert to screen coordinates

    convertedRect.origin = [thisWindow convertBaseToScreen:convertedRect.origin];

    // Convert to other window's coordinates

    convertedRect.origin = [otherWindow convertScreenToBase:convertedRect.origin];

    // Convert to other view's coordinates

    convertedRect = [aView convertRect:convertedRect fromView:nil];

    return convertedRect;

}

@end