/*
 * 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 "WebPDFView.h"

#import "WebDataSourceInternal.h"
#import "WebDocumentInternal.h"
#import "WebDocumentPrivate.h"
#import "WebFrame.h"
#import "WebFrameInternal.h"
#import "WebFrameView.h"
#import "WebLocalizableStrings.h"
#import "WebNSAttributedStringExtras.h"
#import "WebNSPasteboardExtras.h"
#import "WebNSViewExtras.h"
#import "WebPDFRepresentation.h"
#import "WebPreferencesPrivate.h"
#import "WebUIDelegate.h"
#import "WebView.h"
#import "WebViewInternal.h"
#import <WebCore/EventNames.h>
#import <WebCore/KeyboardEvent.h>
#import <WebCore/MouseEvent.h>
#import <WebCore/PlatformKeyboardEvent.h>
#import <JavaScriptCore/Assertions.h>
#import <PDFKit/PDFKit.h>
#import <WebCore/FrameLoader.h>
#import <WebCore/KURL.h>
#import <WebKitSystemInterface.h>

using namespace WebCore;
using namespace EventNames;

#define PDFKitLaunchNotification @"PDFPreviewLaunchPreview"

// QuartzPrivate.h doesn't include the PDFKit private headers, so we can't get at PDFViewPriv.h. (3957971)
// Even if that was fixed, we'd have to tweak compile options to include QuartzPrivate.h. (3957839)

@interface WebPDFView (FileInternal)
+ (Class)_PDFPreviewViewClass;
+ (Class)_PDFViewClass;
- (BOOL)_anyPDFTagsFoundInMenu:(NSMenu *)menu;
- (void)_applyPDFDefaults;
- (NSEvent *)_fakeKeyEventWithFunctionKey:(unichar)functionKey;
- (NSMutableArray *)_menuItemsFromPDFKitForEvent:(NSEvent *)theEvent;
- (void)_openWithFinder:(id)sender;
- (NSString *)_path;
- (PDFView *)_PDFSubview;
- (BOOL)_pointIsInSelection:(NSPoint)point;
- (void)_receivedPDFKitLaunchNotification:(NSNotification *)notification;
- (NSAttributedString *)_scaledAttributedString:(NSAttributedString *)unscaledAttributedString;
- (NSString *)_temporaryPDFDirectoryPath;
- (void)_trackFirstResponder;
@end;

// PDFPrefUpdatingProxy is a class that forwards everything it gets to a target and updates the PDF viewing prefs
// after each of those messages.  We use it as a way to hook all the places that the PDF viewing attrs change.
@interface PDFPrefUpdatingProxy : NSProxy {
    WebPDFView *view;
}
- (id)initWithView:(WebPDFView *)view;
@end

@interface PDFDocument (PDFKitSecretsIKnow)
- (NSPrintOperation *)getPrintOperationForPrintInfo:(NSPrintInfo *)printInfo autoRotate:(BOOL)doRotate;
@end

extern "C" NSString *_NSPathForSystemFramework(NSString *framework);

#pragma mark C UTILITY FUNCTIONS

static void _applicationInfoForMIMEType(NSString *type, NSString **name, NSImage **image)
{
    NSURL *appURL = nil;
    
    OSStatus error = LSCopyApplicationForMIMEType((CFStringRef)type, kLSRolesAll, (CFURLRef *)&appURL);
    if (error != noErr)
        return;
    
    NSString *appPath = [appURL path];
    CFRelease (appURL);
    
    *image = [[NSWorkspace sharedWorkspace] iconForFile:appPath];  
    [*image setSize:NSMakeSize(16.f,16.f)];  
    
    NSString *appName = [[NSFileManager defaultManager] displayNameAtPath:appPath];
    *name = appName;
}

// FIXME 4182876: We can eliminate this function in favor if -isEqual: if [PDFSelection isEqual:] is overridden
// to compare contents.
static BOOL _PDFSelectionsAreEqual(PDFSelection *selectionA, PDFSelection *selectionB)
{
    NSArray *aPages = [selectionA pages];
    NSArray *bPages = [selectionB pages];
    
    if (![aPages isEqual:bPages])
        return NO;
    
    int count = [aPages count];
    int i;
    for (i = 0; i < count; ++i) {
        NSRect aBounds = [selectionA boundsForPage:[aPages objectAtIndex:i]];
        NSRect bBounds = [selectionB boundsForPage:[bPages objectAtIndex:i]];
        if (!NSEqualRects(aBounds, bBounds)) {
            return NO;
        }
    }
    
    return YES;
}

@implementation WebPDFView

#pragma mark WebPDFView API

+ (NSBundle *)PDFKitBundle
{
    static NSBundle *PDFKitBundle = nil;
    if (PDFKitBundle == nil) {
        NSString *PDFKitPath = [_NSPathForSystemFramework(@"Quartz.framework") stringByAppendingString:@"/Frameworks/PDFKit.framework"];
        if (PDFKitPath == nil) {
            LOG_ERROR("Couldn't find PDFKit.framework");
            return nil;
        }
        PDFKitBundle = [NSBundle bundleWithPath:PDFKitPath];
        if (![PDFKitBundle load]) {
            LOG_ERROR("Couldn't load PDFKit.framework");
        }
    }
    return PDFKitBundle;
}

+ (NSArray *)supportedMIMETypes
{
    return [WebPDFRepresentation supportedMIMETypes];
}

- (void)setPDFDocument:(PDFDocument *)doc
{
    [PDFSubview setDocument:doc];
    [self _applyPDFDefaults];
}

#pragma mark NSObject OVERRIDES

- (void)dealloc
{
    ASSERT(!trackedFirstResponder);
    [previewView release];
    [PDFSubview release];
    [path release];
    [PDFSubviewProxy release];
    [super dealloc];
}

#pragma mark NSResponder OVERRIDES

- (void)centerSelectionInVisibleArea:(id)sender
{
    [PDFSubview scrollSelectionToVisible:nil];
}

- (void)scrollPageDown:(id)sender
{
    // PDFView doesn't support this responder method directly, so we pass it a fake key event
    [PDFSubview keyDown:[self _fakeKeyEventWithFunctionKey:NSPageDownFunctionKey]];
}

- (void)scrollPageUp:(id)sender
{
    // PDFView doesn't support this responder method directly, so we pass it a fake key event
    [PDFSubview keyDown:[self _fakeKeyEventWithFunctionKey:NSPageUpFunctionKey]];
}

- (void)scrollLineDown:(id)sender
{
    // PDFView doesn't support this responder method directly, so we pass it a fake key event
    [PDFSubview keyDown:[self _fakeKeyEventWithFunctionKey:NSDownArrowFunctionKey]];
}

- (void)scrollLineUp:(id)sender
{
    // PDFView doesn't support this responder method directly, so we pass it a fake key event
    [PDFSubview keyDown:[self _fakeKeyEventWithFunctionKey:NSUpArrowFunctionKey]];
}

- (void)scrollToBeginningOfDocument:(id)sender
{
    // PDFView doesn't support this responder method directly, so we pass it a fake key event
    [PDFSubview keyDown:[self _fakeKeyEventWithFunctionKey:NSHomeFunctionKey]];
}

- (void)scrollToEndOfDocument:(id)sender
{
    // PDFView doesn't support this responder method directly, so we pass it a fake key event
    [PDFSubview keyDown:[self _fakeKeyEventWithFunctionKey:NSEndFunctionKey]];
}

// jumpToSelection is the old name for what AppKit now calls centerSelectionInVisibleArea. Safari
// was using the old jumpToSelection selector in its menu. Newer versions of Safari will us the
// selector centerSelectionInVisibleArea. We'll leave this old selector in place for two reasons:
// (1) compatibility between older Safari and newer WebKit; (2) other WebKit-based applications
// might be using the jumpToSelection: selector, and we don't want to break them.
- (void)jumpToSelection:(id)sender
{
    [self centerSelectionInVisibleArea:nil];
}

#pragma mark NSView OVERRIDES

- (BOOL)acceptsFirstResponder {
    return YES;
}

- (BOOL)becomeFirstResponder
{
    // This works together with setNextKeyView to splice our PDFSubview into
    // the key loop similar to the way NSScrollView does this.
    NSWindow *window = [self window];
    id newFirstResponder = nil;
    
    if ([window keyViewSelectionDirection] == NSSelectingPrevious) {
        NSView *previousValidKeyView = [self previousValidKeyView];
        if ((previousValidKeyView != self) && (previousValidKeyView != PDFSubview))
            newFirstResponder = previousValidKeyView;
    } else {
        NSView *PDFDocumentView = [PDFSubview documentView];
        if ([PDFDocumentView acceptsFirstResponder])
            newFirstResponder = PDFDocumentView;
    }
    
    if (!newFirstResponder)
        return NO;
    
    if (![window makeFirstResponder:newFirstResponder])
        return NO;
    
    [[dataSource webFrame] _clearSelectionInOtherFrames];
    
    return YES;
}

- (NSView *)hitTest:(NSPoint)point
{
    // Override hitTest so we can override menuForEvent.
    NSEvent *event = [NSApp currentEvent];
    NSEventType type = [event type];
    if (type == NSRightMouseDown || (type == NSLeftMouseDown && ([event modifierFlags] & NSControlKeyMask)))
        return self;

    return [super hitTest:point];
}

- (id)initWithFrame:(NSRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        [self setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
        
        Class previewViewClass = nil;
        if ([[WebPreferences standardPreferences] _usePDFPreviewView])
            previewViewClass = [[self class] _PDFPreviewViewClass];
        
        // We might not have found a previewViewClass even if we looked for one.
        // But if we found the class we should be able to create an instance.
        if (previewViewClass) {
            previewView = [[previewViewClass alloc] initWithFrame:frame];
            ASSERT(previewView);
        }
        
        NSView *topLevelPDFKitView = nil;
        if (previewView) {
            // We'll retain the PDFSubview here so that it is equally retained in all
            // code paths. That way we don't need to worry about conditionally releasing
            // it later.
            PDFSubview = [[previewView performSelector:@selector(pdfView)] retain];
            topLevelPDFKitView = previewView;
        } else {
            PDFSubview = [[[[self class] _PDFViewClass] alloc] initWithFrame:frame];
            topLevelPDFKitView = PDFSubview;
        }
        
        ASSERT(PDFSubview);
        
        [topLevelPDFKitView setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
        [self addSubview:topLevelPDFKitView];
        
        [PDFSubview setDelegate:self];
        written = NO;
        // Messaging this proxy is the same as messaging PDFSubview, with the side effect that the
        // PDF viewing defaults are updated afterwards
        PDFSubviewProxy = (PDFView *)[[PDFPrefUpdatingProxy alloc] initWithView:self];
    }
    
    return self;
}

- (NSMenu *)menuForEvent:(NSEvent *)theEvent
{
    // Start with the menu items supplied by PDFKit, with WebKit tags applied
    NSMutableArray *items = [self _menuItemsFromPDFKitForEvent:theEvent];
    
    // Add in an "Open with <default PDF viewer>" item
    NSString *appName = nil;
    NSImage *appIcon = nil;
    
    _applicationInfoForMIMEType([[dataSource response] MIMEType], &appName, &appIcon);
    if (!appName)
        appName = UI_STRING("Finder", "Default application name for Open With context menu");
    
    // To match the PDFKit style, we'll add Open with Preview even when there's no document yet to view, and
    // disable it using validateUserInterfaceItem.
    NSString *title = [NSString stringWithFormat:UI_STRING("Open with %@", "context menu item for PDF"), appName];
    NSMenuItem *item = [[NSMenuItem alloc] initWithTitle:title action:@selector(_openWithFinder:) keyEquivalent:@""];
    [item setTag:WebMenuItemTagOpenWithDefaultApplication];
    if (appIcon)
        [item setImage:appIcon];
    [items insertObject:item atIndex:0];
    [item release];
    
    [items insertObject:[NSMenuItem separatorItem] atIndex:1];
    
    // pass the items off to the WebKit context menu mechanism
    WebView *webView = [[dataSource webFrame] webView];
    ASSERT(webView);
    NSMenu *menu = [webView _menuForElement:[self elementAtPoint:[self convertPoint:[theEvent locationInWindow] fromView:nil]] defaultItems:items];
    
    // The delegate has now had the opportunity to add items to the standard PDF-related items, or to
    // remove or modify some of the PDF-related items. In 10.4, the PDF context menu did not go through 
    // the standard WebKit delegate path, and so the standard PDF-related items always appeared. For
    // clients that create their own context menu by hand-picking specific items from the default list, such as
    // Safari, none of the PDF-related items will appear until the client is rewritten to explicitly
    // include these items. For backwards compatibility of tip-of-tree WebKit with the 10.4 version of Safari
    // (the configuration that people building open source WebKit use), we'll use the entire set of PDFKit-supplied
    // menu items. This backward-compatibility hack won't work with any non-Safari clients, but this seems OK since
    // (1) the symptom is fairly minor, and (2) we suspect that non-Safari clients are probably using the entire
    // set of default items, rather than manually choosing from them. We can remove this code entirely when we
    // ship a version of Safari that includes the fix for radar 3796579.
    if (![self _anyPDFTagsFoundInMenu:menu] && [[[NSBundle mainBundle] bundleIdentifier] isEqualToString:@"com.apple.Safari"]) {
        [menu addItem:[NSMenuItem separatorItem]];
        NSEnumerator *e = [items objectEnumerator];
        NSMenuItem *menuItem;
        while ((menuItem = [e nextObject]) != nil) {
            // copy menuItem since a given menuItem can be in only one menu at a time, and we don't
            // want to mess with the menu returned from PDFKit.
            [menu addItem:[menuItem copy]];
        }
    }
    
    return menu;
}

- (void)setNextKeyView:(NSView *)aView
{
    // This works together with becomeFirstResponder to splice PDFSubview into
    // the key loop similar to the way NSScrollView and NSClipView do this.
    NSView *documentView = [PDFSubview documentView];
    if (documentView) {
        [documentView setNextKeyView:aView];
        
        // We need to make the documentView be the next view in the keyview loop.
        // It would seem more sensible to do this in our init method, but it turns out
        // that [NSClipView setDocumentView] won't call this method if our next key view
        // is already set, so we wait until we're called before adding this connection.
        // We'll also clear it when we're called with nil, so this could go through the
        // same code path more than once successfully.
        [super setNextKeyView: aView ? documentView : nil];
    } else
        [super setNextKeyView:aView];
}

- (void)viewDidMoveToWindow
{
    // FIXME 2573089: we can observe a notification for first responder changes
    // instead of the very frequent NSWindowDidUpdateNotification if/when 2573089 is addressed.
    NSWindow *newWindow = [self window];
    if (!newWindow)
        return;
    
    [self _trackFirstResponder];
    NSNotificationCenter *notificationCenter = [NSNotificationCenter defaultCenter];
    [notificationCenter addObserver:self
                           selector:@selector(_trackFirstResponder) 
                               name:NSWindowDidUpdateNotification
                             object:newWindow];
    
    if (previewView)
        [notificationCenter addObserver:self
                               selector:@selector(_receivedPDFKitLaunchNotification:)
                                   name:PDFKitLaunchNotification
                                 object:previewView];
}

- (void)viewWillMoveToWindow:(NSWindow *)window
{
    // FIXME 2573089: we can observe a notification for changes to the first responder
    // instead of the very frequent NSWindowDidUpdateNotification if/when 2573089 is addressed.
    NSWindow *oldWindow = [self window];
    if (!oldWindow)
        return;
    
    NSNotificationCenter *notificationCenter = [NSNotificationCenter defaultCenter];
    [notificationCenter removeObserver:self
                                  name:NSWindowDidUpdateNotification
                                object:oldWindow];
    if (previewView)
        [notificationCenter removeObserver:self
                                      name:PDFKitLaunchNotification
                                    object:previewView];
    
    [trackedFirstResponder release];
    trackedFirstResponder = nil;
}

#pragma mark NSUserInterfaceValidations PROTOCOL IMPLEMENTATION

- (BOOL)validateUserInterfaceItem:(id <NSValidatedUserInterfaceItem>)item 
{
    SEL action = [item action];    
    if (action == @selector(takeFindStringFromSelection:) || action == @selector(centerSelectionInVisibleArea:) || action == @selector(jumpToSelection:))
        return [PDFSubview currentSelection] != nil;
    
    if (action == @selector(_openWithFinder:))
        return [PDFSubview document] != nil;

    return YES;
}

#pragma mark INTERFACE BUILDER ACTIONS FOR SAFARI

// Surprisingly enough, this isn't defined in any superclass, though it is defined in assorted AppKit classes since
// it's a standard menu item IBAction.
- (IBAction)copy:(id)sender
{
    [PDFSubview copy:sender];
}

// This used to be a standard IBAction (for Use Selection For Find), but AppKit now uses performFindPanelAction:
// with a menu item tag for this purpose.
- (IBAction)takeFindStringFromSelection:(id)sender
{
    [NSPasteboard _web_setFindPasteboardString:[[PDFSubview currentSelection] string] withOwner:self];
}

#pragma mark WebFrameView UNDECLARED "DELEGATE METHODS"

// This is tested in -[WebFrameView canPrintHeadersAndFooters], but isn't declared anywhere (yuck)
- (BOOL)canPrintHeadersAndFooters
{
    return NO;
}

// This is tested in -[WebFrameView printOperationWithPrintInfo:], but isn't declared anywhere (yuck)
- (NSPrintOperation *)printOperationWithPrintInfo:(NSPrintInfo *)printInfo
{
    return [[PDFSubview document] getPrintOperationForPrintInfo:printInfo autoRotate:YES];
}

#pragma mark WebDocumentView PROTOCOL IMPLEMENTATION

- (void)setDataSource:(WebDataSource *)ds
{
    dataSource = ds;
    [self setFrame:[[self superview] frame]];
}

- (void)dataSourceUpdated:(WebDataSource *)dataSource
{
}

- (void)setNeedsLayout:(BOOL)flag
{
}

- (void)layout
{
}

- (void)viewWillMoveToHostWindow:(NSWindow *)hostWindow
{
}

- (void)viewDidMoveToHostWindow
{
}

#pragma mark WebDocumentElement PROTOCOL IMPLEMENTATION

- (NSDictionary *)elementAtPoint:(NSPoint)point
{
    WebFrame *frame = [dataSource webFrame];
    ASSERT(frame);
    
    return [NSDictionary dictionaryWithObjectsAndKeys:
        frame, WebElementFrameKey, 
        [NSNumber numberWithBool:[self _pointIsInSelection:point]], WebElementIsSelectedKey,
        nil];
}

- (NSDictionary *)elementAtPoint: