// Copyright 2013 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/ui/libgtk2ui/app_indicator_icon.h"

#include <dlfcn.h>
#include <gtk/gtk.h>

#include "base/bind.h"
#include "base/environment.h"
#include "base/files/file_util.h"
#include "base/md5.h"
#include "base/memory/ref_counted_memory.h"
#include "base/nix/xdg_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/utf_string_conversions.h"
#include "base/threading/sequenced_worker_pool.h"
#include "chrome/browser/ui/libgtk2ui/app_indicator_icon_menu.h"
#include "content/public/browser/browser_thread.h"
#include "ui/base/models/menu_model.h"
#include "ui/gfx/image/image.h"
#include "ui/gfx/image/image_skia.h"

namespace {

typedef enum {
  APP_INDICATOR_CATEGORY_APPLICATION_STATUS,
  APP_INDICATOR_CATEGORY_COMMUNICATIONS,
  APP_INDICATOR_CATEGORY_SYSTEM_SERVICES,
  APP_INDICATOR_CATEGORY_HARDWARE,
  APP_INDICATOR_CATEGORY_OTHER
} AppIndicatorCategory;

typedef enum {
  APP_INDICATOR_STATUS_PASSIVE,
  APP_INDICATOR_STATUS_ACTIVE,
  APP_INDICATOR_STATUS_ATTENTION
} AppIndicatorStatus;

typedef AppIndicator* (*app_indicator_new_func)(const gchar* id,
                                                const gchar* icon_name,
                                                AppIndicatorCategory category);

typedef AppIndicator* (*app_indicator_new_with_path_func)(
    const gchar* id,
    const gchar* icon_name,
    AppIndicatorCategory category,
    const gchar* icon_theme_path);

typedef void (*app_indicator_set_status_func)(AppIndicator* self,
                                              AppIndicatorStatus status);

typedef void (*app_indicator_set_attention_icon_full_func)(
    AppIndicator* self,
    const gchar* icon_name,
    const gchar* icon_desc);

typedef void (*app_indicator_set_menu_func)(AppIndicator* self, GtkMenu* menu);

typedef void (*app_indicator_set_icon_full_func)(AppIndicator* self,
                                                 const gchar* icon_name,
                                                 const gchar* icon_desc);

typedef void (*app_indicator_set_icon_theme_path_func)(
    AppIndicator* self,
    const gchar* icon_theme_path);

bool g_attempted_load = false;
bool g_opened = false;

// Retrieved functions from libappindicator.
app_indicator_new_func app_indicator_new = NULL;
app_indicator_new_with_path_func app_indicator_new_with_path = NULL;
app_indicator_set_status_func app_indicator_set_status = NULL;
app_indicator_set_attention_icon_full_func
    app_indicator_set_attention_icon_full = NULL;
app_indicator_set_menu_func app_indicator_set_menu = NULL;
app_indicator_set_icon_full_func app_indicator_set_icon_full = NULL;
app_indicator_set_icon_theme_path_func app_indicator_set_icon_theme_path = NULL;

void EnsureMethodsLoaded() {
  if (g_attempted_load)
    return;

  g_attempted_load = true;

  // Only use libappindicator where it is needed to support dbus based status
  // icons. In particular, libappindicator does not support a click action.
  scoped_ptr<base::Environment> env(base::Environment::Create());
  base::nix::DesktopEnvironment environment =
      base::nix::GetDesktopEnvironment(env.get());
  if (environment != base::nix::DESKTOP_ENVIRONMENT_KDE4 &&
      environment != base::nix::DESKTOP_ENVIRONMENT_UNITY) {
    return;
  }

  void* indicator_lib = dlopen("libappindicator.so", RTLD_LAZY);
  if (!indicator_lib) {
    indicator_lib = dlopen("libappindicator.so.1", RTLD_LAZY);
  }
  if (!indicator_lib) {
    indicator_lib = dlopen("libappindicator.so.0", RTLD_LAZY);
  }
  if (!indicator_lib) {
    return;
  }

  g_opened = true;

  app_indicator_new = reinterpret_cast<app_indicator_new_func>(
      dlsym(indicator_lib, "app_indicator_new"));

  app_indicator_new_with_path =
      reinterpret_cast<app_indicator_new_with_path_func>(
          dlsym(indicator_lib, "app_indicator_new_with_path"));

  app_indicator_set_status = reinterpret_cast<app_indicator_set_status_func>(
      dlsym(indicator_lib, "app_indicator_set_status"));

  app_indicator_set_attention_icon_full =
      reinterpret_cast<app_indicator_set_attention_icon_full_func>(
          dlsym(indicator_lib, "app_indicator_set_attention_icon_full"));

  app_indicator_set_menu = reinterpret_cast<app_indicator_set_menu_func>(
      dlsym(indicator_lib, "app_indicator_set_menu"));

  app_indicator_set_icon_full =
      reinterpret_cast<app_indicator_set_icon_full_func>(
          dlsym(indicator_lib, "app_indicator_set_icon_full"));

  app_indicator_set_icon_theme_path =
      reinterpret_cast<app_indicator_set_icon_theme_path_func>(
          dlsym(indicator_lib, "app_indicator_set_icon_theme_path"));
}

// Returns whether a temporary directory should be created for each app
// indicator image.
bool ShouldCreateTempDirectoryPerImage(bool using_kde4) {
  // Create a new temporary directory for each image on Unity since using a
  // single temporary directory seems to have issues when changing icons in
  // quick succession.
  return !using_kde4;
}

// Returns the subdirectory of |temp_dir| in which the app indicator image
// should be saved.
base::FilePath GetImageDirectoryPath(bool using_kde4,
                                     const base::FilePath& temp_dir) {
  // On KDE4, an image located in a directory ending with
  // "icons/hicolor/16x16/apps" can be used as the app indicator image because
  // "/usr/share/icons/hicolor/16x16/apps" exists.
  return using_kde4 ?
      temp_dir.AppendASCII("icons").AppendASCII("hicolor").AppendASCII("16x16").
          AppendASCII("apps") :
      temp_dir;
}

std::string GetImageFileNameForKDE4(
    const scoped_refptr<base::RefCountedMemory>& png_data) {
  // On KDE4, the name of the image file for each different looking bitmap must
  // be unique. It must also be unique across runs of Chrome.
  base::MD5Digest digest;
  base::MD5Sum(png_data->front_as<char>(), png_data->size(), &digest);
  return base::StringPrintf("chrome_app_indicator_%s.png",
                            base::MD5DigestToBase16(digest).c_str());
}

std::string GetImageFileNameForNonKDE4(int icon_change_count,
                                       const std::string& id) {
  return base::StringPrintf("%s_%d.png", id.c_str(), icon_change_count);
}

// Returns the "icon theme path" given the file path of the app indicator image.
std::string GetIconThemePath(bool using_kde4,
                             const base::FilePath& image_path) {
  return using_kde4 ?
      image_path.DirName().DirName().DirName().DirName().value() :
      image_path.DirName().value();
}

base::FilePath CreateTempImageFile(bool using_kde4,
                                   gfx::ImageSkia* image_ptr,
                                   int icon_change_count,
                                   std::string id,
                                   const base::FilePath& previous_file_path) {
  scoped_ptr<gfx::ImageSkia> image(image_ptr);

  scoped_refptr<base::RefCountedMemory> png_data =
      gfx::Image(*image.get()).As1xPNGBytes();
  if (png_data->size() == 0) {
    // If the bitmap could not be encoded to PNG format, skip it.
    LOG(WARNING) << "Could not encode icon";
    return base::FilePath();
  }

  base::FilePath new_file_path;
  if (previous_file_path.empty() ||
      ShouldCreateTempDirectoryPerImage(using_kde4)) {
    base::FilePath tmp_dir;
    if (!base::CreateNewTempDirectory(base::FilePath::StringType(), &tmp_dir))
      return base::FilePath();
    new_file_path = GetImageDirectoryPath(using_kde4, tmp_dir);
    if (new_file_path != tmp_dir) {
      if (!base::CreateDirectory(new_file_path))
        return base::FilePath();
    }
  } else {
    new_file_path = previous_file_path.DirName();
  }

  new_file_path = new_file_path.Append(using_kde4 ?
      GetImageFileNameForKDE4(png_data) :
      GetImageFileNameForNonKDE4(icon_change_count, id));

  int bytes_written =
      base::WriteFile(new_file_path,
                      png_data->front_as<char>(), png_data->size());

  if (bytes_written != static_cast<int>(png_data->size()))
    return base::FilePath();
  return new_file_path;
}

void DeleteTempDirectory(const base::FilePath& dir_path) {
  if (dir_path.empty())
    return;
  base::DeleteFile(dir_path, true);
}

}  // namespace

namespace libgtk2ui {

AppIndicatorIcon::AppIndicatorIcon(std::string id,
                                   const gfx::ImageSkia& image,
                                   const base::string16& tool_tip)
    : id_(id),
      using_kde4_(false),
      icon_(NULL),
      menu_model_(NULL),
      icon_change_count_(0),
      weak_factory_(this) {
  scoped_ptr<base::Environment> env(base::Environment::Create());
  using_kde4_ = base::nix::GetDesktopEnvironment(env.get()) ==
      base::nix::DESKTOP_ENVIRONMENT_KDE4;

  EnsureMethodsLoaded();
  tool_tip_ = base::UTF16ToUTF8(tool_tip);
  SetImage(image);
}
AppIndicatorIcon::~AppIndicatorIcon() {
  if (icon_) {
    app_indicator_set_status(icon_, APP_INDICATOR_STATUS_PASSIVE);
    g_object_unref(icon_);
    content::BrowserThread::GetBlockingPool()->PostTask(
        FROM_HERE,
        base::Bind(&DeleteTempDirectory, icon_file_path_.DirName()));
  }
}

// static
bool AppIndicatorIcon::CouldOpen() {
  EnsureMethodsLoaded();
  return g_opened;
}

void AppIndicatorIcon::SetImage(const gfx::ImageSkia& image) {
  if (!g_opened)
    return;

  ++icon_change_count_;

  // We create a deep copy of the image since it may have been freed by the time
  // it's accessed in the other thread.
  scoped_ptr<gfx::ImageSkia> safe_image(image.DeepCopy());
  base::PostTaskAndReplyWithResult(
      content::BrowserThread::GetBlockingPool()
          ->GetTaskRunnerWithShutdownBehavior(
                base::SequencedWorkerPool::SKIP_ON_SHUTDOWN).get(),
      FROM_HERE,
      base::Bind(&CreateTempImageFile,
                 using_kde4_,
                 safe_image.release(),
                 icon_change_count_,
                 id_,
                 icon_file_path_),
      base::Bind(&AppIndicatorIcon::SetImageFromFile,
                 weak_factory_.GetWeakPtr()));
}

void AppIndicatorIcon::SetToolTip(const base::string16& tool_tip) {
  DCHECK(!tool_tip_.empty());
  tool_tip_ = base::UTF16ToUTF8(tool_tip);
  UpdateClickActionReplacementMenuItem();
}

void AppIndicatorIcon::UpdatePlatformContextMenu(ui::MenuModel* model) {
  if (!g_opened)
    return;

  menu_model_ = model;

  // The icon is created asynchronously so it might not exist when the menu is
  // set.
  if (icon_)
    SetMenu();
}

void AppIndicatorIcon::RefreshPlatformContextMenu() {
  menu_->Refresh();
}

void AppIndicatorIcon::SetImageFromFile(const base::FilePath& icon_file_path) {
  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
  if (icon_file_path.empty())
    return;

  base::FilePath old_path = icon_file_path_;
  icon_file_path_ = icon_file_path;

  std::string icon_name =
      icon_file_path_.BaseName().RemoveExtension().value();
  std::string icon_dir = GetIconThemePath(using_kde4_, icon_file_path);
  if (!icon_) {
    icon_ =
        app_indicator_new_with_path(id_.c_str(),
                                    icon_name.c_str(),
                                    APP_INDICATOR_CATEGORY_APPLICATION_STATUS,
                                    icon_dir.c_str());
    app_indicator_set_status(icon_, APP_INDICATOR_STATUS_ACTIVE);
    SetMenu();
  } else {
    // Currently we are creating a new temp directory every time the icon is
    // set. So we need to set the directory each time.
    app_indicator_set_icon_theme_path(icon_, icon_dir.c_str());
    app_indicator_set_icon_full(icon_, icon_name.c_str(), "icon");

    if (ShouldCreateTempDirectoryPerImage(using_kde4_)) {
      // Delete previous icon directory.
      content::BrowserThread::GetBlockingPool()->PostTask(
          FROM_HERE,
          base::Bind(&DeleteTempDirectory, old_path.DirName()));
    }
  }
}

void AppIndicatorIcon::SetMenu() {
  menu_.reset(new AppIndicatorIconMenu(menu_model_));
  UpdateClickActionReplacementMenuItem();
  app_indicator_set_menu(icon_, menu_->GetGtkMenu());
}

void AppIndicatorIcon::UpdateClickActionReplacementMenuItem() {
  // The menu may not have been created yet.
  if (!menu_.get())
    return;

  if (!delegate()->HasClickAction() && menu_model_)
    return;

  DCHECK(!tool_tip_.empty());
  menu_->UpdateClickActionReplacementMenuItem(
      tool_tip_.c_str(),
      base::Bind(&AppIndicatorIcon::OnClickActionReplacementMenuItemActivated,
                 base::Unretained(this)));
}

void AppIndicatorIcon::OnClickActionReplacementMenuItemActivated() {
  if (delegate())
    delegate()->OnClick();
}

}  // namespace libgtk2ui