/*
 * Copyright (C) 2005, 2006, 2007 Apple Inc. All rights reserved.
 *           (C) 2007 Graham Dennis (graham.dennis@gmail.com)
 *           (C) 2007 Eric Seidel <eric@webkit.org>
 *
 * 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.
 */

#include "config.h"
#include "PixelDumpSupport.h"
#include "PixelDumpSupportCG.h"

#include "DumpRenderTree.h" 
#include "LayoutTestController.h"
#include <CoreGraphics/CGBitmapContext.h>
#include <wtf/Assertions.h>
#include <wtf/RefPtr.h>

#import <WebKit/WebCoreStatistics.h>
#import <WebKit/WebDocumentPrivate.h>
#import <WebKit/WebHTMLViewPrivate.h>
#import <WebKit/WebKit.h>
#import <WebKit/WebViewPrivate.h>

static PassRefPtr<BitmapContext> createBitmapContext(size_t pixelsWide, size_t pixelsHigh, size_t& rowBytes, void*& buffer)
{
    rowBytes = (4 * pixelsWide + 63) & ~63; // Use a multiple of 64 bytes to improve CG performance

    buffer = calloc(pixelsHigh, rowBytes);
    if (!buffer)
        return 0;
    
    // Creating this bitmap in the device color space prevents any color conversion when the image of the web view is drawn into it.
    RetainPtr<CGColorSpaceRef> colorSpace(AdoptCF, CGColorSpaceCreateDeviceRGB());
    CGContextRef context = CGBitmapContextCreate(buffer, pixelsWide, pixelsHigh, 8, rowBytes, colorSpace.get(), kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host); // Use ARGB8 on PPC or BGRA8 on X86 to improve CG performance
    if (!context) {
        free(buffer);
        return 0;
    }

    return BitmapContext::createByAdoptingBitmapAndContext(buffer, context);
}

static void paintRepaintRectOverlay(WebView* webView, CGContextRef context)
{
    CGRect viewRect = NSRectToCGRect([webView bounds]);

    CGContextSaveGState(context);

    // Using a transparency layer is easier than futzing with clipping.
    CGContextBeginTransparencyLayer(context, 0);

    // Flip the context.
    CGContextScaleCTM(context, 1, -1);
    CGContextTranslateCTM(context, 0, -viewRect.size.height);
    
    CGContextSetRGBFillColor(context, 0, 0, 0, static_cast<CGFloat>(0.66));
    CGContextFillRect(context, viewRect);

    NSArray *repaintRects = [webView trackedRepaintRects];
    if (repaintRects) {
        
        for (NSValue *value in repaintRects) {
            CGRect currRect = NSRectToCGRect([value rectValue]);
            CGContextClearRect(context, currRect);
        }
    }
    
    CGContextEndTransparencyLayer(context);
    CGContextRestoreGState(context);
}

PassRefPtr<BitmapContext> createBitmapContextFromWebView(bool onscreen, bool incrementalRepaint, bool sweepHorizontally, bool drawSelectionRect)
{
    WebView* view = [mainFrame webView];

    // If the WebHTMLView uses accelerated compositing, we need for force the on-screen capture path
    // and also force Core Animation to start its animations with -display since the DRT window has autodisplay disabled.
    if ([view _isUsingAcceleratedCompositing])
        onscreen = YES;

    float deviceScaleFactor = [view _backingScaleFactor];
    NSSize webViewSize = [view frame].size;
    size_t pixelsWide = static_cast<size_t>(webViewSize.width * deviceScaleFactor);
    size_t pixelsHigh = static_cast<size_t>(webViewSize.height * deviceScaleFactor);
    size_t rowBytes = 0;
    void* buffer = 0;
    RefPtr<BitmapContext> bitmapContext = createBitmapContext(pixelsWide, pixelsHigh, rowBytes, buffer);
    if (!bitmapContext)
        return 0;
    CGContextRef context = bitmapContext->cgContext();
    CGContextScaleCTM(context, deviceScaleFactor, deviceScaleFactor);

    NSGraphicsContext *nsContext = [NSGraphicsContext graphicsContextWithGraphicsPort:context flipped:NO];
    ASSERT(nsContext);
    
    if (incrementalRepaint) {
        if (sweepHorizontally) {
            for (NSRect column = NSMakeRect(0, 0, 1, webViewSize.height); column.origin.x < webViewSize.width; column.origin.x++)
                [view displayRectIgnoringOpacity:column inContext:nsContext];
        } else {
            for (NSRect line = NSMakeRect(0, 0, webViewSize.width, 1); line.origin.y < webViewSize.height; line.origin.y++)
                [view displayRectIgnoringOpacity:line inContext:nsContext];
        }
    } else {
        if (deviceScaleFactor != 1) {
            // Call displayRectIgnoringOpacity for HiDPI tests since it ensures we paint directly into the context 
            // that we have appropriately sized and scaled.
            [view displayRectIgnoringOpacity:[view bounds] inContext:nsContext];
            if ([view isTrackingRepaints])
                paintRepaintRectOverlay(view, context);
        } else if (onscreen) {
            // displayIfNeeded does not update the CA layers if the layer-hosting view was not marked as needing display, so
            // we're at the mercy of CA's display-link callback to update layers in time. So we need to force a display of the view
            // to get AppKit to update the CA layers synchronously.
            // FIXME: this will break repaint testing if we have compositing in repaint tests
            // (displayWebView() painted gray over the webview, but we'll be making everything repaint again).
            [view display];

            // Ask the window server to provide us a composited version of the *real* window content including surfaces (i.e. OpenGL content)
            // Note that the returned image might differ very slightly from the window backing because of dithering artifacts in the window server compositor.
            CGImageRef image = CGWindowListCreateImage(CGRectNull, kCGWindowListOptionIncludingWindow, [[view window] windowNumber], kCGWindowImageBoundsIgnoreFraming | kCGWindowImageShouldBeOpaque);
            CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image), CGImageGetHeight(image)), image);
            CGImageRelease(image);

            if ([view isTrackingRepaints])
                paintRepaintRectOverlay(view, context);
        } else {
            // Make sure the view has been painted.
            [view displayIfNeeded];

            // Grab directly the contents of the window backing buffer (this ignores any surfaces on the window)
            // FIXME: This path is suboptimal: data is read from window backing store, converted to RGB8 then drawn again into an RGBA8 bitmap
            [view lockFocus];
            NSBitmapImageRep *imageRep = [[[NSBitmapImageRep alloc] initWithFocusedViewRect:[view frame]] autorelease];
            [view unlockFocus];

            RetainPtr<NSGraphicsContext> savedContext = [NSGraphicsContext currentContext];
            [NSGraphicsContext setCurrentContext:nsContext];
            [imageRep draw];
            
            if ([view isTrackingRepaints])
                paintRepaintRectOverlay(view, context);
            
            [NSGraphicsContext setCurrentContext:savedContext.get()];
        }
    }

    if (drawSelectionRect) {
        NSView *documentView = [[mainFrame frameView] documentView];
        ASSERT([documentView conformsToProtocol:@protocol(WebDocumentSelection)]);
        NSRect rect = [documentView convertRect:[(id <WebDocumentSelection>)documentView selectionRect] fromView:nil];
        CGContextSaveGState(context);
        CGContextSetLineWidth(context, 1.0);
        CGContextSetRGBStrokeColor(context, 1.0, 0.0, 0.0, 1.0);
        CGContextStrokeRect(context, CGRectMake(rect.origin.x, rect.origin.y, rect.size.width, rect.size.height));
        CGContextRestoreGState(context);
    }
    
    return bitmapContext.release();
}

PassRefPtr<BitmapContext> createPagedBitmapContext()
{
    int pageWidthInPixels = LayoutTestController::maxViewWidth;
    int pageHeightInPixels = LayoutTestController::maxViewHeight;
    int numberOfPages = [mainFrame numberOfPages:pageWidthInPixels:pageHeightInPixels];
    size_t rowBytes = 0;
    void* buffer = 0;

    RefPtr<BitmapContext> bitmapContext = createBitmapContext(pageWidthInPixels, numberOfPages * (pageHeightInPixels + 1) - 1, rowBytes, buffer);
    [mainFrame printToCGContext:bitmapContext->cgContext():pageWidthInPixels:pageHeightInPixels];
    return bitmapContext.release();
}