Source/WebKit2/UIProcess/ios/WKPDFView.mm

   1 /*
   2  * Copyright (C) 2014 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  14  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  15  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  17  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  18  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  19  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  22  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  23  * THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #import "config.h"
  27 #import "WKPDFView.h"
  28
  29 #if PLATFORM(IOS)
  30
  31 #import "SessionState.h"
  32 #import "WKPDFPageNumberIndicator.h"
  33 #import "WKWebViewInternal.h"
  34 #import "WebPageProxy.h"
  35 #import <CorePDF/UIPDFDocument.h>
  36 #import <CorePDF/UIPDFLinkAnnotation.h>
  37 #import <CorePDF/UIPDFPage.h>
  38 #import <CorePDF/UIPDFPageView.h>
  39 #import <UIKit/UIScrollView_Private.h>
  40 #import <WebCore/FloatRect.h>
  41 #import <chrono>
  42 #import <wtf/RetainPtr.h>
  43 #import <wtf/Vector.h>
  44
  45 using namespace WebCore;
  46
  47 const CGFloat pdfPageMargin = 8;
  48 const CGFloat pdfMinimumZoomScale = 1;
  49 const CGFloat pdfMaximumZoomScale = 5;
  50
  51 const float overdrawHeightMultiplier = 1.5;
  52
  53 static const CGFloat smartMagnificationElementPadding = 0.05;
  54
  55 typedef struct {
  56     CGRect frame;
  57     RetainPtr<UIPDFPageView> view;
  58     RetainPtr<UIPDFPage> page;
  59 } PDFPageInfo;
  60
  61 @interface WKPDFView ()
  62 - (void)_resetZoomAnimated:(BOOL)animated;
  63 @end
  64
  65 @implementation WKPDFView {
  66     RetainPtr<UIPDFDocument> _pdfDocument;
  67     RetainPtr<NSString> _suggestedFilename;
  68     RetainPtr<WKPDFPageNumberIndicator> _pageNumberIndicator;
  69
  70     Vector<PDFPageInfo> _pages;
  71     unsigned _centerPageNumber;
  72
  73     CGSize _minimumSize;
  74     CGSize _overlaidAccessoryViewsInset;
  75     WKWebView *_webView;
  76     UIScrollView *_scrollView;
  77     UIView *_fixedOverlayView;
  78
  79     BOOL _isStartingZoom;
  80     BOOL _isPerformingSameDocumentNavigation;
  81 }
  82
  83 - (instancetype)web_initWithFrame:(CGRect)frame webView:(WKWebView *)webView
  84 {
  85     if (!(self = [super initWithFrame:frame]))
  86         return nil;
  87
  88     self.backgroundColor = [UIColor grayColor];
  89
  90     _webView = webView;
  91
  92     _scrollView = webView.scrollView;
  93     [_scrollView setMinimumZoomScale:pdfMinimumZoomScale];
  94     [_scrollView setMaximumZoomScale:pdfMaximumZoomScale];
  95     [_scrollView setBackgroundColor:[UIColor grayColor]];
  96
  97     return self;
  98 }
  99
 100 - (void)dealloc
 101 {
 102     [self _clearPages];
 103     [_pageNumberIndicator removeFromSuperview];
 104     [super dealloc];
 105 }
 106
 107 - (NSString *)suggestedFilename
 108 {
 109     return _suggestedFilename.get();
 110 }
 111
 112 - (CGPDFDocumentRef)pdfDocument
 113 {
 114     return [_pdfDocument CGDocument];
 115 }
 116
 117 - (void)_clearPages
 118 {
 119     for (auto& page : _pages) {
 120         [page.view removeFromSuperview];
 121         [page.view setDelegate:nil];
 122         [[page.view annotationController] setDelegate:nil];
 123     }
 124
 125     _pages.clear();
 126 }
 127
 128 - (void)web_setContentProviderData:(NSData *)data suggestedFilename:(NSString *)filename
 129 {
 130     _suggestedFilename = adoptNS([filename copy]);
 131
 132     [self _clearPages];
 133
 134     RetainPtr<CGDataProvider> dataProvider = adoptCF(CGDataProviderCreateWithCFData((CFDataRef)data));
 135     RetainPtr<CGPDFDocumentRef> cgPDFDocument = adoptCF(CGPDFDocumentCreateWithProvider(dataProvider.get()));
 136     _pdfDocument = adoptNS([[UIPDFDocument alloc] initWithCGPDFDocument:cgPDFDocument.get()]);
 137
 138     // FIXME: restore the scroll position and page scale if navigating from the back/forward list.
 139
 140     [self _computePageAndDocumentFrames];
 141     [self _revalidateViews];
 142 }
 143
 144 - (void)web_setMinimumSize:(CGSize)size
 145 {
 146     _minimumSize = size;
 147
 148     [self _computePageAndDocumentFrames];
 149     [self _revalidateViews];
 150 }
 151
 152 - (void)scrollViewDidScroll:(UIScrollView *)scrollView
 153 {
 154     if (scrollView.isZoomBouncing || scrollView._isAnimatingZoom)
 155         return;
 156
 157     [self _revalidateViews];
 158
 159     if (!_isPerformingSameDocumentNavigation)
 160         [_pageNumberIndicator show];
 161 }
 162
 163 - (void)_revalidateViews
 164 {
 165     if (_isStartingZoom)
 166         return;
 167
 168     CGRect targetRect = [_scrollView convertRect:_scrollView.bounds toView:self];
 169
 170     // We apply overdraw after applying scale in order to avoid excessive
 171     // memory use caused by scaling the overdraw.
 172     CGRect targetRectWithOverdraw = CGRectInset(targetRect, 0, -targetRect.size.height * overdrawHeightMultiplier);
 173     CGRect targetRectForCenterPage = CGRectInset(targetRect, 0, targetRect.size.height / 2 - pdfPageMargin * 2);
 174
 175     _centerPageNumber = 0;
 176     unsigned currentPage = 0;
 177
 178     for (auto& pageInfo : _pages) {
 179         ++currentPage;
 180
 181         if (!CGRectIntersectsRect(pageInfo.frame, targetRectWithOverdraw)) {
 182             [pageInfo.view removeFromSuperview];
 183             pageInfo.view = nullptr;
 184             continue;
 185         }
 186
 187         if (!_centerPageNumber && CGRectIntersectsRect(pageInfo.frame, targetRectForCenterPage))
 188             _centerPageNumber = currentPage;
 189
 190         if (pageInfo.view)
 191             continue;
 192
 193         pageInfo.view = adoptNS([[UIPDFPageView alloc] initWithPage:pageInfo.page.get() tiledContent:YES]);
 194         [pageInfo.view setUseBackingLayer:YES];
 195         [pageInfo.view setDelegate:self];
 196         [[pageInfo.view annotationController] setDelegate:self];
 197         [self addSubview:pageInfo.view.get()];
 198
 199         [pageInfo.view setFrame:pageInfo.frame];
 200         [pageInfo.view contentLayer].contentsScale = self.window.screen.scale;
 201     }
 202
 203     [self _updatePageNumberIndicator];
 204 }
 205
 206 - (CGPoint)_offsetForPageNumberIndicator
 207 {
 208     UIEdgeInsets contentInset = [_webView _computedContentInset];
 209     return CGPointMake(contentInset.left, contentInset.top + _overlaidAccessoryViewsInset.height);
 210 }
 211
 212 - (void)_updatePageNumberIndicator
 213 {
 214     if (_isPerformingSameDocumentNavigation)
 215         return;
 216
 217     if (!_pageNumberIndicator)
 218         _pageNumberIndicator = adoptNS([[WKPDFPageNumberIndicator alloc] initWithFrame:CGRectZero]);
 219
 220     [_fixedOverlayView addSubview:_pageNumberIndicator.get()];
 221
 222     [_pageNumberIndicator setCurrentPageNumber:_centerPageNumber];
 223     [_pageNumberIndicator moveToPoint:[self _offsetForPageNumberIndicator] animated:NO];
 224 }
 225
 226 - (void)web_setOverlaidAccessoryViewsInset:(CGSize)inset
 227 {
 228     _overlaidAccessoryViewsInset = inset;
 229     [_pageNumberIndicator moveToPoint:[self _offsetForPageNumberIndicator] animated:YES];
 230 }
 231
 232 - (void)web_computedContentInsetDidChange
 233 {
 234     [self _updatePageNumberIndicator];
 235 }
 236
 237 - (void)web_setFixedOverlayView:(UIView *)fixedOverlayView
 238 {
 239     _fixedOverlayView = fixedOverlayView;
 240
 241     if (_pageNumberIndicator)
 242         [_fixedOverlayView addSubview:_pageNumberIndicator.get()];
 243 }
 244
 245 - (void)web_didSameDocumentNavigation:(WKSameDocumentNavigationType)navigationType
 246 {
 247     // Check for kWKSameDocumentNavigationSessionStatePop instead of kWKSameDocumentNavigationAnchorNavigation since the
 248     // latter is only called once when navigating to the same anchor in succession. If the user navigates to a page
 249     // then scrolls back and clicks on the same link a second time, we want to scroll again.
 250     if (navigationType != kWKSameDocumentNavigationSessionStatePop)
 251         return;
 252
 253     // FIXME: restore the scroll position and page scale if navigating back from a fragment.
 254
 255     NSString *fragment = _webView.URL.fragment;
 256     if (![fragment hasPrefix:@"page"])
 257         return;
 258
 259     NSInteger pageIndex = [[fragment substringFromIndex:4] integerValue] - 1;
 260     if (pageIndex < 0 || static_cast<std::size_t>(pageIndex) >= _pages.size())
 261         return;
 262
 263     _isPerformingSameDocumentNavigation = YES;
 264
 265     [_pageNumberIndicator hide];
 266     [self _resetZoomAnimated:NO];
 267
 268     // Ensure that the page margin is visible below the content inset.
 269     const CGFloat verticalOffset = _pages[pageIndex].frame.origin.y - _webView._computedContentInset.top - pdfPageMargin;
 270     [_scrollView setContentOffset:CGPointMake(_scrollView.contentOffset.x, verticalOffset) animated:NO];
 271
 272     _isPerformingSameDocumentNavigation = NO;
 273 }
 274
 275 - (void)_computePageAndDocumentFrames
 276 {
 277     NSUInteger pageCount = [_pdfDocument numberOfPages];
 278     [_pageNumberIndicator setPageCount:pageCount];
 279
 280     [self _clearPages];
 281
 282     _pages.reserveCapacity(pageCount);
 283
 284     CGRect pageFrame = CGRectMake(0, 0, _minimumSize.width, _minimumSize.height);
 285     for (NSUInteger pageNumber = 0; pageNumber < pageCount; ++pageNumber) {
 286         UIPDFPage *page = [_pdfDocument pageAtIndex:pageNumber];
 287         if (!page)
 288             continue;
 289
 290         CGSize pageSize = [page cropBoxAccountForRotation].size;
 291         pageFrame.size.height = pageSize.height / pageSize.width * pageFrame.size.width;
 292         CGRect pageFrameWithMarginApplied = CGRectInset(pageFrame, pdfPageMargin, pdfPageMargin);
 293
 294         PDFPageInfo pageInfo;
 295         pageInfo.page = page;
 296         pageInfo.frame = pageFrameWithMarginApplied;
 297         _pages.append(pageInfo);
 298         pageFrame.origin.y += pageFrame.size.height - pdfPageMargin;
 299     }
 300
 301     CGFloat scale = _scrollView.zoomScale;
 302     CGRect newFrame = [self frame];
 303     newFrame.size.width = _minimumSize.width * scale;
 304     newFrame.size.height = std::max(pageFrame.origin.y + pdfPageMargin, _minimumSize.height) * scale;
 305
 306     [self setFrame:newFrame];
 307     [_scrollView setContentSize:newFrame.size];
 308 }
 309
 310 - (void)_resetZoomAnimated:(BOOL)animated
 311 {
 312     _isStartingZoom = YES;
 313
 314     CGRect scrollViewBounds = _scrollView.bounds;
 315     CGPoint centerOfPageInDocumentCoordinates = [_scrollView convertPoint:CGPointMake(CGRectGetMidX(scrollViewBounds), CGRectGetMidY(scrollViewBounds)) toView:self];
 316     [_webView _zoomOutWithOrigin:centerOfPageInDocumentCoordinates animated:animated];
 317
 318     _isStartingZoom = NO;
 319 }
 320
 321 #pragma mark UIPDFPageViewDelegate
 322
 323 - (void)zoom:(UIPDFPageView *)pageView to:(CGRect)targetRect atPoint:(CGPoint)origin kind:(UIPDFObjectKind)kind
 324 {
 325     _isStartingZoom = YES;
 326
 327     BOOL isImage = kind == kUIPDFObjectKindGraphic;
 328
 329     if (!isImage)
 330         targetRect = CGRectInset(targetRect, smartMagnificationElementPadding * targetRect.size.width, smartMagnificationElementPadding * targetRect.size.height);
 331
 332     CGRect rectInDocumentCoordinates = [pageView convertRect:targetRect toView:self];
 333     CGPoint originInDocumentCoordinates = [pageView convertPoint:origin toView:self];
 334
 335     [_webView _zoomToRect:rectInDocumentCoordinates withOrigin:originInDocumentCoordinates fitEntireRect:isImage minimumScale:pdfMinimumZoomScale maximumScale:pdfMaximumZoomScale minimumScrollDistance:0];
 336
 337     _isStartingZoom = NO;
 338 }
 339
 340 - (void)resetZoom:(UIPDFPageView *)pageView
 341 {
 342     [self _resetZoomAnimated:YES];
 343 }
 344
 345 #pragma mark UIPDFAnnotationControllerDelegate
 346
 347 - (void)annotation:(UIPDFAnnotation *)annotation wasTouchedAtPoint:(CGPoint)point controller:(UIPDFAnnotationController *)controller
 348 {
 349     ASSERT(isMainThread());
 350
 351     if (![annotation isKindOfClass:[UIPDFLinkAnnotation class]])
 352         return;
 353
 354     UIPDFLinkAnnotation *linkAnnotation = (UIPDFLinkAnnotation *)annotation;
 355     String urlString;
 356     if (NSURL *url = linkAnnotation.url)
 357         urlString = url.absoluteString;
 358     else if (NSUInteger pageNumber = linkAnnotation.pageNumber) {
 359         urlString = ASCIILiteral("#page");
 360         urlString.append(String::number(pageNumber));
 361     }
 362
 363     if (urlString.isEmpty())
 364         return;
 365
 366     CGPoint documentPoint = [controller.pageView convertPoint:point toView:self];
 367     CGPoint screenPoint = [self.window convertPoint:[self convertPoint:documentPoint toView:nil] toWindow:nil];
 368     static const int64_t dispatchOffset = std::chrono::duration_cast<std::chrono::nanoseconds>(std::chrono::milliseconds(200)).count();
 369     RetainPtr<WKWebView> retainedWebView = _webView;
 370
 371     // Call navigateToURLWithSimulatedClick() on a delay so that a tap highlight can be shown.
 372     dispatch_after(dispatch_time(DISPATCH_TIME_NOW, dispatchOffset), dispatch_get_main_queue(), ^ {
 373         retainedWebView->_page->navigateToURLWithSimulatedClick(urlString, roundedIntPoint(documentPoint), roundedIntPoint(screenPoint));
 374     });
 375 }
 376
 377 @end
 378
 379 #endif /* PLATFORM(IOS) */