// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#import "chrome/browser/ui/cocoa/panels/panel_titlebar_view_cocoa.h"

#import <Cocoa/Cocoa.h>

#include "base/logging.h"
#include "base/mac/scoped_nsautorelease_pool.h"
#import "chrome/browser/ui/cocoa/panels/panel_window_controller_cocoa.h"
#import "chrome/browser/ui/panels/panel_constants.h"
#include "chrome/grit/generated_resources.h"
#include "grit/theme_resources.h"
#import "third_party/google_toolbox_for_mac/src/AppKit/GTMNSBezierPath+RoundRect.h"
#import "third_party/google_toolbox_for_mac/src/AppKit/GTMNSColor+Luminance.h"
#include "ui/base/cocoa/cocoa_base_utils.h"
#import "ui/base/cocoa/hover_image_button.h"
#import "ui/base/cocoa/nsview_additions.h"
#include "ui/base/l10n/l10n_util_mac.h"
#include "ui/base/resource/resource_bundle.h"
#include "ui/gfx/image/image.h"
#include "ui/gfx/scoped_ns_graphics_context_save_gstate_mac.h"

// 'Glint' is a glowing light animation on the titlebar to attract user's
// attention. Numbers are arbitrary, based on several tries.
const double kGlintAnimationDuration = 1.5;
const double kGlintRepeatIntervalSeconds = 1.0;
const int kNumberOfGlintRepeats = 4;  // 5 total, including initial flash.

// Used to implement TestingAPI
static NSEvent* MakeMouseEvent(NSEventType type,
                               NSPoint point,
                               int modifierFlags,
                               int clickCount) {
  return [NSEvent mouseEventWithType:type
                            location:point
                       modifierFlags:modifierFlags
                           timestamp:0
                        windowNumber:0
                             context:nil
                         eventNumber:0
                          clickCount:clickCount
                            pressure:0.0];
}

// Test drag controller - does not contain a nested message loop, directly
// invokes the dragStarted/dragProgress instead.
@interface TestDragController : MouseDragController {
 @private
  BOOL dragStarted_;
}
- (void)mouseDragged:(NSEvent*)event;
@end

@implementation TestDragController
// Bypass nested message loop for tests. There is no need to check for
// threshold here as the base class does because tests only simulate a single
// 'mouse drag' to the destination point.
- (void)mouseDragged:(NSEvent*)event {
  if (!dragStarted_) {
    [[self client] dragStarted:[self initialMouseLocation]];
    dragStarted_ = YES;
  }

  [[self client] dragProgress:[event locationInWindow]];
}
@end

@implementation PanelTitlebarOverlayView
// Sometimes we do not want to bring chrome window to foreground when we click
// on any part of the titlebar. To do this, we first postpone the window
// reorder here (shouldDelayWindowOrderingForEvent is called during when mouse
// button is pressed but before mouseDown: is dispatched) and then complete
// canceling the reorder by [NSApp preventWindowOrdering] in mouseDown handler
// of this view.
- (BOOL)shouldDelayWindowOrderingForEvent:(NSEvent*)theEvent {
  disableReordering_ = ![controller_ canBecomeKeyWindow];
  return disableReordering_;
}

- (void)mouseDown:(NSEvent*)event {
  if (disableReordering_)
    [NSApp preventWindowOrdering];
  disableReordering_ = NO;
  // Continue bubbling the event up the chain of responders.
  [super mouseDown:event];
}

- (BOOL)acceptsFirstMouse:(NSEvent*)event {
  return YES;
}
@end

@implementation RepaintAnimation
- (id)initWithView:(NSView*)targetView duration:(double) duration {
  if ((self = [super initWithDuration:duration
                       animationCurve:NSAnimationEaseInOut])) {
    [self setAnimationBlockingMode:NSAnimationNonblocking];
    targetView_ = targetView;
  }
  return self;
}

- (void)setCurrentProgress:(NSAnimationProgress)progress {
  [super setCurrentProgress:progress];
  [targetView_ setNeedsDisplay:YES];
}
@end


@implementation PanelTitlebarViewCocoa

- (id)initWithFrame:(NSRect)frame {
  if ((self = [super initWithFrame:frame]))
    dragController_.reset([[MouseDragController alloc] initWithClient:self]);
  return self;
}

- (void)dealloc {
  [[NSNotificationCenter defaultCenter] removeObserver:self];
  [self stopGlintAnimation];
  [super dealloc];
}

- (void)onCloseButtonClick:(id)sender {
  [controller_ closePanel];
}

- (void)onMinimizeButtonClick:(id)sender {
  [controller_ minimizeButtonClicked:[[NSApp currentEvent] modifierFlags]];
}

- (void)onRestoreButtonClick:(id)sender {
  [controller_ restoreButtonClicked:[[NSApp currentEvent] modifierFlags]];
}

- (void)drawRect:(NSRect)rect {
  if (isDrawingAttention_) {
    NSColor* attentionColor = [NSColor colorWithCalibratedRed:0x53/255.0
                                                        green:0xa9/255.0
                                                         blue:0x3f/255.0
                                                        alpha:1.0];
    [attentionColor set];
    NSRectFillUsingOperation([self bounds], NSCompositeSourceOver);

    if ([glintAnimation_ isAnimating]) {
      base::scoped_nsobject<NSGradient> glint([NSGradient alloc]);
      float currentAlpha = 0.8 * [glintAnimation_ currentValue];
      NSColor* startColor = [NSColor colorWithCalibratedWhite:1.0
                                                        alpha:currentAlpha];
      NSColor* endColor = [NSColor colorWithCalibratedWhite:1.0
                                                      alpha:0.0];
      [glint initWithColorsAndLocations:
           startColor, 0.0, startColor, 0.3, endColor, 1.0, nil];
      NSRect bounds = [self bounds];
      [glint drawInRect:bounds relativeCenterPosition:NSZeroPoint];
    }
  } else {
    BOOL isActive = [[self window] isMainWindow];

    // If titlebar is close to minimized state or is at minimized state and only
    // shows a few pixels, change the color to something light and add border.
    NSRect windowFrame = [[self window] frame];
    if (NSHeight(windowFrame) < 8) {
      NSColor* lightBackgroundColor =
          [NSColor colorWithCalibratedRed:0xf5/255.0
                                    green:0xf4/255.0
                                     blue:0xf0/255.0
                                    alpha:1.0];
      [lightBackgroundColor set];
      NSRectFill([self bounds]);

      NSColor* borderColor =
          [NSColor colorWithCalibratedRed:0xc9/255.0
                                    green:0xc9/255.0
                                     blue:0xc9/255.0
                                    alpha:1.0];
      [borderColor set];
      NSFrameRect([self bounds]);
    } else {
      // use solid black-ish colors.
      NSColor* backgroundColor = isActive ?
        [NSColor colorWithCalibratedRed:0x3a/255.0
                                  green:0x3d/255.0
                                   blue:0x3d/255.0
                                  alpha:1.0] :
        [NSColor colorWithCalibratedRed:0x7a/255.0
                                  green:0x7c/255.0
                                   blue:0x7c/255.0
                                  alpha:1.0];

      [backgroundColor set];
      NSRectFill([self bounds]);
    }
  }

  NSColor* titleColor = [NSColor colorWithCalibratedRed:0xf9/255.0
                                                  green:0xf9/255.0
                                                   blue:0xf9/255.0
                                                  alpha:1.0];
  [title_ setTextColor:titleColor];
}

- (void)attach {
  // Interface Builder can not put a view as a sibling of contentView,
  // so need to do it here. Placing ourself as the last child of the
  // internal view allows us to draw on top of the titlebar.
  // Note we must use [controller_ window] here since we have not been added
  // to the view hierarchy yet.
  NSView* contentView = [[controller_ window] contentView];
  NSView* rootView = [contentView superview];
  [rootView addSubview:self];

  // Figure out the rectangle of the titlebar and set us on top of it.
  // The titlebar covers window's root view where not covered by contentView.
  // Compute the titlebar frame in coordinate system of the window's root view.
  //        NSWindow
  //           |
  //    ___root_view____
  //     |            |
  // contentView  titlebar
  NSSize titlebarSize = NSMakeSize(0, panel::kTitlebarHeight);
  titlebarSize = [contentView convertSize:titlebarSize toView:rootView];
  NSRect rootViewBounds = [[self superview] bounds];
  NSRect titlebarFrame =
      NSMakeRect(NSMinX(rootViewBounds),
                 NSMaxY(rootViewBounds) - titlebarSize.height,
                 NSWidth(rootViewBounds),
                 titlebarSize.height);
  [self setFrame:titlebarFrame];

  [title_ setFont:[[NSFontManager sharedFontManager]
                   fontWithFamily:@"Arial"
                           traits:NSBoldFontMask
                           weight:0
                             size:14.0]];
  [title_ setDrawsBackground:NO];

  ResourceBundle& rb = ResourceBundle::GetSharedInstance();

  [self initializeImageButton:customCloseButton_
      image:rb.GetNativeImageNamed(IDR_PANEL_CLOSE).ToNSImage()
      hoverImage:rb.GetNativeImageNamed(IDR_PANEL_CLOSE_H).ToNSImage()
      pressedImage:rb.GetNativeImageNamed(IDR_PANEL_CLOSE_C).ToNSImage()
      toolTip:l10n_util::GetNSStringWithFixup(IDS_PANEL_CLOSE_TOOLTIP)];

  // Iniitalize the minimize and restore buttons.
  [self initializeImageButton:minimizeButton_
      image:rb.GetNativeImageNamed(IDR_PANEL_MINIMIZE).ToNSImage()
      hoverImage:rb.GetNativeImageNamed(IDR_PANEL_MINIMIZE_H).ToNSImage()
      pressedImage:rb.GetNativeImageNamed(IDR_PANEL_MINIMIZE_C).ToNSImage()
      toolTip:l10n_util::GetNSStringWithFixup(IDS_PANEL_MINIMIZE_TOOLTIP)];

  [self initializeImageButton:restoreButton_
      image:rb.GetNativeImageNamed(IDR_PANEL_RESTORE).ToNSImage()
      hoverImage:rb.GetNativeImageNamed(IDR_PANEL_RESTORE_H).ToNSImage()
      pressedImage:rb.GetNativeImageNamed(IDR_PANEL_RESTORE_C).ToNSImage()
      toolTip:l10n_util::GetNSStringWithFixup(IDS_PANEL_RESTORE_TOOLTIP)];

  [controller_ updateTitleBarMinimizeRestoreButtonVisibility];

  [self updateCustomButtonsLayout];

  // Set autoresizing behavior: glued to edges on left, top and right.
  [self setAutoresizingMask:(NSViewMinYMargin | NSViewWidthSizable)];

  [[NSNotificationCenter defaultCenter]
      addObserver:self
         selector:@selector(didChangeFrame:)
             name:NSViewFrameDidChangeNotification
           object:self];
  [[NSNotificationCenter defaultCenter]
      addObserver:self
         selector:@selector(didChangeMainWindow:)
             name:NSWindowDidBecomeMainNotification
           object:[self window]];
  [[NSNotificationCenter defaultCenter]
      addObserver:self
         selector:@selector(didChangeMainWindow:)
             name:NSWindowDidResignMainNotification
           object:[self window]];
}

- (void)initializeImageButton:(HoverImageButton*)button
                        image:(NSImage*)image
                   hoverImage:(NSImage*)hoverImage
                 pressedImage:(NSImage*)pressedImage
                      toolTip:(NSString*)toolTip {
  [button setDefaultImage:image];
  [button setHoverImage:hoverImage];
  [button setPressedImage:pressedImage];
  [button setToolTip:toolTip];
  [[button cell] setHighlightsBy:NSNoCellMask];
}

- (void)setTitle:(NSString*)newTitle {
  [title_ setStringValue:newTitle];
  [self updateIconAndTitleLayout];
}

- (void)setIcon:(NSView*)newIcon {
  [icon_ removeFromSuperview];
  icon_ = newIcon;
  if (icon_) {
    [self addSubview:icon_ positioned:NSWindowBelow relativeTo:overlay_];
    [icon_ setWantsLayer:YES];
  }
  [self updateIconAndTitleLayout];
}

- (NSView*)icon {
  return icon_;
}

- (void)setMinimizeButtonVisibility:(BOOL)visible {
  [minimizeButton_ setHidden:!visible];
}

- (void)setRestoreButtonVisibility:(BOOL)visible {
  [restoreButton_ setHidden:!visible];
}

- (void)updateCustomButtonsLayout {
  NSRect bounds = [self bounds];
  NSRect closeButtonFrame = [customCloseButton_ frame];
  closeButtonFrame.size.width = panel::kPanelButtonSize;
  closeButtonFrame.size.height = panel::kPanelButtonSize;
  closeButtonFrame.origin.x =
      NSWidth(bounds) - NSWidth(closeButtonFrame) - panel::kButtonPadding;
  closeButtonFrame.origin.y =
      (NSHeight(bounds) - NSHeight(closeButtonFrame)) / 2;
  [customCloseButton_ setFrame:closeButtonFrame];

  NSRect buttonFrame = [minimizeButton_ frame];
  buttonFrame.size.width = panel::kPanelButtonSize;
  buttonFrame.size.height = panel::kPanelButtonSize;
  buttonFrame.origin.x =
      closeButtonFrame.origin.x - NSWidth(buttonFrame) - panel::kButtonPadding;
  buttonFrame.origin.y = (NSHeight(bounds) - NSHeight(buttonFrame)) / 2;
  [minimizeButton_ setFrame:buttonFrame];
  [restoreButton_ setFrame:buttonFrame];
}

- (void)updateIconAndTitleLayout {
  NSRect iconFrame = [icon_ frame];
  // NSTextField for title_ is set to Layout:Truncate, LineBreaks:TruncateTail
  // in Interface Builder so it is sized in a single-line mode.
  [title_ sizeToFit];
  NSRect titleFrame = [title_ frame];
  // Only one of minimize/restore button is visible at a time so just allow for
  // the width of one of them.
  NSRect minimizeRestoreButtonFrame = [minimizeButton_ frame];
  NSRect bounds = [self bounds];

  // Place the icon and title at the left edge of the titlebar.
  int iconWidth = NSWidth(iconFrame);
  int titleWidth = NSWidth(titleFrame);
  int availableWidth = minimizeRestoreButtonFrame.origin.x -
      panel::kTitleAndButtonPadding;

  int paddings = panel::kTitlebarLeftPadding + panel::kIconAndTitlePadding;
  if (paddings + iconWidth + titleWidth > availableWidth)
    titleWidth = availableWidth - iconWidth - paddings;
  if (titleWidth < 0)
    titleWidth = 0;

  iconFrame.origin.x = panel::kTitlebarLeftPadding;
  iconFrame.origin.y = (NSHeight(bounds) - NSHeight(iconFrame)) / 2;
  [icon_ setFrame:iconFrame];

  titleFrame.origin.x = paddings + iconWidth;
  // In bottom-heavy text labels, let's compensate for occasional integer
  // rounding to avoid text label to feel too low.
  titleFrame.origin.y = (NSHeight(bounds) - NSHeight(titleFrame)) / 2 + 2;
  titleFrame.size.width = titleWidth;
  [title_ setFrame:titleFrame];
}

// PanelManager controls size/position of the window.
- (BOOL)mouseDownCanMoveWindow {
  return NO;
}

- (BOOL)acceptsFirstMouse:(NSEvent*)event {
  return YES;
}

- (void)didChangeFrame:(NSNotification*)notification {
  // Update buttons first because title layout depends on buttons layout.
  [self updateCustomButtonsLayout];
  [self updateIconAndTitleLayout];
}

- (void)didChangeMainWindow:(NSNotification*)notification {
  [self setNeedsDisplay:YES];
}

- (void)mouseDown:(NSEvent*)event {
  [dragController_ mouseDown:event];
}

- (void)mouseUp:(NSEvent*)event {
  [dragController_ mouseUp:event];

  if ([event clickCount] == 1)
    [controller_ onTitlebarMouseClicked:[event modifierFlags]];
  else if ([event clickCount] == 2)
    [controller_ onTitlebarDoubleClicked:[event modifierFlags]];
}

- (void)mouseDragged:(NSEvent*)event {
  [dragController_ mouseDragged:event];
}

// MouseDragControllerClient implementaiton

- (void)prepareForDrag {
}

- (void)dragStarted:(NSPoint)initialMouseLocation {
  NSPoint initialMouseLocationScreen = ui::ConvertPointFromWindowToScreen(
      [self window], initialMouseLocation);
  [controller_ startDrag:initialMouseLocationScreen];
}

- (void)dragEnded:(BOOL)cancelled {
  [controller_ endDrag:cancelled];
}

- (void)dragProgress:(NSPoint)mouseLocation {
  NSPoint mouseLocationScreen = ui::ConvertPointFromWindowToScreen(
      [self window], mouseLocation);
  [controller_ drag:mouseLocationScreen];
}

- (void)cleanupAfterDrag {
}

// End of MouseDragControllerClient implementaiton

- (void)drawAttention {
  if (isDrawingAttention_)
    return;
  isDrawingAttention_ = YES;

  [self startGlintAnimation];
}

- (void)stopDrawingAttention {
  if (!isDrawingAttention_)
    return;
  isDrawingAttention_ = NO;

  [self stopGlintAnimation];
  [self setNeedsDisplay:YES];
}

- (BOOL)isDrawingAttention {
  return isDrawingAttention_;
}

- (void)startGlintAnimation {
  glintCounter_ = 0;
  [self restartGlintAnimation:nil];
}

- (void)stopGlintAnimation {
  if (glintAnimationTimer_.get()) {
    [glintAnimationTimer_ invalidate];
    glintAnimationTimer_.reset();
  }
  if ([glintAnimation_ isAnimating])
    [glintAnimation_ stopAnimation];
}

- (void)restartGlintAnimation:(NSTimer*)timer {
  if (!glintAnimation_.get()) {
    glintAnimation_.reset(
        [[RepaintAnimation alloc] initWithView:self
                                      duration:kGlintAnimationDuration]);
    [glintAnimation_ setDelegate:self];
  }
  [glintAnimation_ startAnimation];
}

// NSAnimationDelegate method.
- (void)animationDidEnd:(NSAnimation*)animation {
  if (animation != glintAnimation_.get())
    return;
  if (glintCounter_ >= kNumberOfGlintRepeats)
    return;
  glintCounter_++;
  // Restart after a timeout.
  glintAnimationTimer_.reset([[NSTimer
      scheduledTimerWithTimeInterval:kGlintRepeatIntervalSeconds
                              target:self
                            selector:@selector(restartGlintAnimation:)
                            userInfo:nil
                             repeats:NO] retain]);
}

// NSAnimationDelegate method.
- (float)animation:(NSAnimation *)animation
  valueForProgress:(NSAnimationProgress)progress {
  if (animation != glintAnimation_.get())
    return progress;

  // Converts 0..1 progression into a sharper raise/fall.
  float result = progress < 0.5 ? progress : 1.0 - progress;
  result = 4.0 * result * result;
  return result;
}

// (Private/TestingAPI)
- (PanelWindowControllerCocoa*)controller {
  return controller_;
}

- (NSTextField*)title {
  return title_;
}

- (void)simulateCloseButtonClick {
  [[customCloseButton_ cell] performClick:customCloseButton_];
}

- (void)pressLeftMouseButtonTitlebar:(NSPoint)mouseLocation
                           modifiers:(int)modifierFlags {
  // Override the drag controller. It's ok to create a new one for each drag.
  dragController_.reset([[TestDragController alloc] initWithClient:self]);
  // Convert from Cocoa's screen coordinates to base coordinates since the mouse
  // event takes base (NSWindow) coordinates.
  NSPoint mouseLocationWindow = ui::ConvertPointFromScreenToWindow(
      [self window], mouseLocation);
  NSEvent* event = MakeMouseEvent(NSLeftMouseDown, mouseLocationWindow,
      modifierFlags, 0);
  [self mouseDown:event];
}

- (void)releaseLeftMouseButtonTitlebar:(int)modifierFlags {
  NSEvent* event = MakeMouseEvent(NSLeftMouseUp, NSZeroPoint, modifierFlags, 1);
  [self mouseUp:event];
}

- (void)dragTitlebar:(NSPoint)mouseLocation {
  // Convert from Cocoa's screen coordinates to base coordinates since the mouse
  // event takes base (NSWindow) coordinates.
  NSPoint mouseLocationWindow = ui::ConvertPointFromScreenToWindow(
      [self window], mouseLocation);
  NSEvent* event =
      MakeMouseEvent(NSLeftMouseDragged, mouseLocationWindow, 0, 0);
  [self mouseDragged:event];
}

- (void)cancelDragTitlebar {
  [self dragEnded:YES];
}

- (void)finishDragTitlebar {
  [self dragEnded:NO];
}

- (NSButton*)closeButton {
  return closeButton_;
}

- (NSButton*)minimizeButton {
  return minimizeButton_;
}

- (NSButton*)restoreButton {
  return restoreButton_;
}

@end