// Copyright (c) 2009 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.

#include "chrome/browser/gtk/custom_button.h"

#include "app/l10n_util.h"
#include "app/resource_bundle.h"
#include "app/theme_provider.h"
#include "base/basictypes.h"
#include "base/gfx/gtk_util.h"
#include "chrome/browser/gtk/gtk_theme_provider.h"
#include "chrome/common/notification_service.h"
#include "grit/theme_resources.h"

CustomDrawButtonBase::CustomDrawButtonBase(GtkThemeProvider* theme_provider,
    int normal_id, int active_id, int highlight_id, int depressed_id)
    : paint_override_(-1),
      normal_id_(normal_id),
      active_id_(active_id),
      highlight_id_(highlight_id),
      depressed_id_(depressed_id),
      theme_provider_(theme_provider) {
  if (theme_provider) {
    // Load images by pretending that we got a BROWSER_THEME_CHANGED
    // notification.
    theme_provider->InitThemesFor(this);

    registrar_.Add(this,
                   NotificationType::BROWSER_THEME_CHANGED,
                   NotificationService::AllSources());
  } else {
    // Load the button images from the resource bundle.
    ResourceBundle& rb = ResourceBundle::GetSharedInstance();
    pixbufs_[GTK_STATE_NORMAL] =
        normal_id ? rb.GetRTLEnabledPixbufNamed(normal_id) : NULL;
    pixbufs_[GTK_STATE_ACTIVE] =
        active_id ? rb.GetRTLEnabledPixbufNamed(active_id) : NULL;
    pixbufs_[GTK_STATE_PRELIGHT] =
        highlight_id ? rb.GetRTLEnabledPixbufNamed(highlight_id) : NULL;
    pixbufs_[GTK_STATE_SELECTED] = NULL;
    pixbufs_[GTK_STATE_INSENSITIVE] =
        depressed_id ? rb.GetRTLEnabledPixbufNamed(depressed_id) : NULL;
  }
}

CustomDrawButtonBase::~CustomDrawButtonBase() {
}

gboolean CustomDrawButtonBase::OnExpose(GtkWidget* widget, GdkEventExpose* e) {
  GdkPixbuf* pixbuf = pixbufs_[paint_override_ >= 0 ?
                               paint_override_ : GTK_WIDGET_STATE(widget)];

  // Fall back to the default image if we don't have one for this state.
  if (!pixbuf)
    pixbuf = pixbufs_[GTK_STATE_NORMAL];

  if (!pixbuf)
    return FALSE;

  cairo_t* cairo_context = gdk_cairo_create(GDK_DRAWABLE(widget->window));
  cairo_translate(cairo_context, widget->allocation.x, widget->allocation.y);

  // The widget might be larger than the pixbuf. Paint the pixbuf flush with the
  // start of the widget (left for LTR, right for RTL).
  int pixbuf_width = gdk_pixbuf_get_width(pixbuf);
  int widget_width = widget->allocation.width;
  int x = gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL ?
      widget_width - pixbuf_width : 0;

  gdk_cairo_set_source_pixbuf(cairo_context, pixbuf, x, 0);
  cairo_paint(cairo_context);
  cairo_destroy(cairo_context);

  return TRUE;
}

void CustomDrawButtonBase::Observe(NotificationType type,
    const NotificationSource& source, const NotificationDetails& details) {
  DCHECK(theme_provider_);
  DCHECK(NotificationType::BROWSER_THEME_CHANGED == type);

  // TODO(tc): Add GetRTLEnabledPixbufNamed to ThemeProviderGtk.
  pixbufs_[GTK_STATE_NORMAL] =
      normal_id_ ? theme_provider_->GetPixbufNamed(normal_id_) : NULL;
  pixbufs_[GTK_STATE_ACTIVE] =
      active_id_ ? theme_provider_->GetPixbufNamed(active_id_) : NULL;
  pixbufs_[GTK_STATE_PRELIGHT] =
      highlight_id_ ? theme_provider_->GetPixbufNamed(highlight_id_) : NULL;
  pixbufs_[GTK_STATE_SELECTED] = NULL;
  pixbufs_[GTK_STATE_INSENSITIVE] =
      depressed_id_ ? theme_provider_->GetPixbufNamed(depressed_id_) : NULL;
}

CustomDrawButton::CustomDrawButton(int normal_id, int active_id,
    int highlight_id, int depressed_id, const char* stock_id)
    : button_base_(NULL, normal_id, active_id, highlight_id, depressed_id),
      gtk_stock_name_(stock_id),
      has_expose_signal_handler_(false) {
  Init();

  // Initialize the theme stuff with no theme_provider.
  SetBrowserTheme(NULL);
}

CustomDrawButton::CustomDrawButton(GtkThemeProvider* theme_provider,
    int normal_id, int active_id, int highlight_id, int depressed_id,
    const char* stock_id)
    : button_base_(theme_provider, normal_id, active_id, highlight_id,
                   depressed_id),
      gtk_stock_name_(stock_id),
      has_expose_signal_handler_(false) {
  Init();

  theme_provider->InitThemesFor(this);
  registrar_.Add(this,
                 NotificationType::BROWSER_THEME_CHANGED,
                 NotificationService::AllSources());
}

CustomDrawButton::~CustomDrawButton() {
  widget_.Destroy();
}

void CustomDrawButton::Init() {
  widget_.Own(gtk_button_new());
  GTK_WIDGET_UNSET_FLAGS(widget_.get(), GTK_CAN_FOCUS);
}

void CustomDrawButton::Observe(NotificationType type,
    const NotificationSource& source, const NotificationDetails& details) {
  DCHECK(NotificationType::BROWSER_THEME_CHANGED == type);

  GtkThemeProvider* provider = static_cast<GtkThemeProvider*>(
      Source<GtkThemeProvider>(source).ptr());
  SetBrowserTheme(provider);
}

void CustomDrawButton::SetPaintOverride(GtkStateType state) {
  button_base_.set_paint_override(state);
  gtk_widget_queue_draw(widget_.get());
}

void CustomDrawButton::UnsetPaintOverride() {
  button_base_.set_paint_override(-1);
  gtk_widget_queue_draw(widget_.get());
}

// static
gboolean CustomDrawButton::OnCustomExpose(GtkWidget* widget,
                                          GdkEventExpose* e,
                                          CustomDrawButton* button) {
  return button->button_base_.OnExpose(widget, e);
}

// static
CustomDrawButton* CustomDrawButton::CloseButton() {
  CustomDrawButton* button =
      new CustomDrawButton(IDR_CLOSE_BAR, IDR_CLOSE_BAR_P,
                           IDR_CLOSE_BAR_H, 0, NULL);
  return button;
}

void CustomDrawButton::SetBrowserTheme(GtkThemeProvider* theme_provider) {
  if (theme_provider && theme_provider->UseGtkTheme() && gtk_stock_name_) {
    gtk_button_set_image(
        GTK_BUTTON(widget_.get()),
        gtk_image_new_from_stock(gtk_stock_name_, GTK_ICON_SIZE_BUTTON));
    gtk_widget_set_size_request(widget_.get(), -1, -1);
    gtk_widget_set_app_paintable(widget_.get(), FALSE);
    gtk_widget_set_double_buffered(widget_.get(), TRUE);

    if (has_expose_signal_handler_)
      gtk_signal_disconnect_by_data(GTK_OBJECT(widget_.get()), this);
    has_expose_signal_handler_ = false;
  } else {
    gtk_widget_set_size_request(widget_.get(),
                                gdk_pixbuf_get_width(button_base_.pixbufs(0)),
                                gdk_pixbuf_get_height(button_base_.pixbufs(0)));

    gtk_widget_set_app_paintable(widget_.get(), TRUE);
    // We effectively double-buffer by virtue of having only one image...
    gtk_widget_set_double_buffered(widget_.get(), FALSE);
    g_signal_connect(G_OBJECT(widget_.get()), "expose-event",
                     G_CALLBACK(OnCustomExpose), this);
    has_expose_signal_handler_ = true;
  }
}