// Copyright 2019 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/web_applications/manifest_update_task.h"

#include <map>
#include <memory>
#include <utility>
#include <vector>

#include "base/containers/contains.h"
#include "base/feature_list.h"
#include "base/strings/utf_string_conversions.h"
#include "chrome/browser/browser_features.h"
#include "chrome/browser/web_applications/components/web_app_constants.h"
#include "chrome/browser/web_applications/components/web_app_helpers.h"
#include "chrome/browser/web_applications/components/web_app_install_utils.h"
#include "chrome/browser/web_applications/components/web_app_ui_manager.h"
#include "chrome/browser/web_applications/components/web_application_info.h"
#include "chrome/browser/web_applications/os_integration_manager.h"
#include "chrome/browser/web_applications/web_app.h"
#include "chrome/browser/web_applications/web_app_icon_manager.h"
#include "chrome/browser/web_applications/web_app_install_manager.h"
#include "chrome/browser/web_applications/web_app_installation_utils.h"
#include "chrome/browser/web_applications/web_app_registrar.h"
#include "chrome/common/chrome_features.h"
#include "components/webapps/browser/installable/installable_manager.h"
#include "third_party/blink/public/common/features.h"
#include "third_party/blink/public/common/manifest/manifest_util.h"
#include "ui/gfx/skia_util.h"

namespace web_app {

struct IconDiff {
 public:
  IconDiff() = default;
  explicit IconDiff(bool changes) { changes_detected = changes; }
  IconDiff(const SkBitmap& before_icon, const SkBitmap& after_icon) {
    changes_detected = true;
    before = before_icon;
    after = after_icon;
  }
  bool changes_detected = false;
  SkBitmap before;
  SkBitmap after;
};

namespace {

IconDiff HaveIconContentsChanged(
    const std::map<SquareSizePx, SkBitmap>& disk_icon_bitmaps,
    const std::map<SquareSizePx, SkBitmap>& downloaded_icon_bitmaps) {
  if (downloaded_icon_bitmaps.size() != disk_icon_bitmaps.size())
    return IconDiff(true);

  for (const std::pair<const SquareSizePx, SkBitmap>& entry :
       downloaded_icon_bitmaps) {
    SquareSizePx size = entry.first;
    const SkBitmap& downloaded_bitmap = entry.second;

    auto it = disk_icon_bitmaps.find(size);
    if (it == disk_icon_bitmaps.end())
      return IconDiff(true);

    const SkBitmap& disk_bitmap = it->second;
    if (!gfx::BitmapsAreEqual(downloaded_bitmap, disk_bitmap))
      return IconDiff(disk_bitmap, downloaded_bitmap);
  }

  return IconDiff(false);
}

IconDiff HaveIconBitmapsChanged(const IconBitmaps& disk_icon_bitmaps,
                                const IconBitmaps& downloaded_icon_bitmaps) {
  IconDiff icon_diff = HaveIconContentsChanged(disk_icon_bitmaps.any,
                                               downloaded_icon_bitmaps.any);
  if (icon_diff.changes_detected)
    return icon_diff;

  icon_diff = HaveIconContentsChanged(disk_icon_bitmaps.maskable,
                                      downloaded_icon_bitmaps.maskable);
  if (icon_diff.changes_detected)
    return icon_diff;

  icon_diff = HaveIconContentsChanged(disk_icon_bitmaps.monochrome,
                                      downloaded_icon_bitmaps.monochrome);
  if (icon_diff.changes_detected)
    return icon_diff;

  return IconDiff(false);
}

// Some apps, such as pre-installed apps, have been vetted and are therefore
// considered safe and permitted to update their names.
bool AllowUnpromptedNameUpdate(const AppId& app_id,
                               const WebAppRegistrar& registrar) {
  const WebApp* web_app = registrar.GetAppById(app_id);
  if (!web_app)
    return false;
  return CanWebAppUpdateIdentity(web_app);
}

// Some apps, such as pre-installed apps, have been vetted and are therefore
// considered safe and permitted to update their icon. For others, the feature
// flag needs to be on.
bool AllowUnpromptedIconUpdate(const AppId& app_id,
                               const WebAppRegistrar& registrar) {
  const WebApp* web_app = registrar.GetAppById(app_id);
  if (!web_app)
    return false;
  return CanWebAppUpdateIdentity(web_app) ||
         base::FeatureList::IsEnabled(features::kWebAppManifestIconUpdating);
}

}  // namespace

ManifestUpdateTask::ManifestUpdateTask(
    const GURL& url,
    const AppId& app_id,
    content::WebContents* web_contents,
    StoppedCallback stopped_callback,
    bool hang_for_testing,
    const WebAppRegistrar& registrar,
    const WebAppIconManager& icon_manager,
    WebAppUiManager* ui_manager,
    WebAppInstallManager* install_manager,
    OsIntegrationManager& os_integration_manager)
    : content::WebContentsObserver(web_contents),
      registrar_(registrar),
      icon_manager_(icon_manager),
      ui_manager_(*ui_manager),
      install_manager_(*install_manager),
      os_integration_manager_(os_integration_manager),
      url_(url),
      app_id_(app_id),
      stopped_callback_(std::move(stopped_callback)),
      hang_for_testing_(hang_for_testing) {
  // Task starts by waiting for DidFinishLoad() to be called.
  stage_ = Stage::kPendingPageLoad;
}

ManifestUpdateTask::~ManifestUpdateTask() {
#if DCHECK_IS_ON()
  if (destructor_called_ptr_) {
    DCHECK(!(*destructor_called_ptr_));
    *destructor_called_ptr_ = true;
  }
#endif
}

// content::WebContentsObserver:
void ManifestUpdateTask::DidFinishLoad(
    content::RenderFrameHost* render_frame_host,
    const GURL& validated_url) {
  if (stage_ != Stage::kPendingPageLoad || hang_for_testing_)
    return;

  if (render_frame_host->GetParent() != nullptr)
    return;

  stage_ = Stage::kPendingInstallableData;
  webapps::InstallableParams params;
  params.valid_primary_icon = true;
  params.valid_manifest = true;
  params.check_webapp_manifest_display = false;
  webapps::InstallableManager::FromWebContents(web_contents())
      ->GetData(params,
                base::BindOnce(&ManifestUpdateTask::OnDidGetInstallableData,
                               AsWeakPtr()));
}

// content::WebContentsObserver:
void ManifestUpdateTask::WebContentsDestroyed() {
  switch (stage_) {
    case Stage::kPendingPageLoad:
    case Stage::kPendingInstallableData:
    case Stage::kPendingIconDownload:
    case Stage::kPendingIconReadFromDisk:
      DestroySelf(ManifestUpdateResult::kWebContentsDestroyed);
      return;
    case Stage::kPendingAppIdentityCheck:
    case Stage::kPendingWindowsClosed:
    case Stage::kPendingMaybeReadExistingIcons:
    case Stage::kPendingInstallation:
    case Stage::kPendingAssociationsUpdate:
      // These stages should have stopped listening to the web contents.
      NOTREACHED() << static_cast<int>(stage_);
      Observe(nullptr);
      break;
  }
}

void ManifestUpdateTask::OnDidGetInstallableData(
    const webapps::InstallableData& data) {
  DCHECK_EQ(stage_, Stage::kPendingInstallableData);

  if (!data.NoBlockingErrors()) {
    DestroySelf(ManifestUpdateResult::kAppNotEligible);
    return;
  }

  web_application_info_.emplace();
  UpdateWebAppInfoFromManifest(data.manifest, data.manifest_url,
                               &web_application_info_.value());

  // We cannot allow the app ID to change via the manifest changing. We rely on
  // fixed app IDs to determine whether web apps installed in the user sync
  // profile has been sync installed across devices. If we allowed the app ID to
  // change then the sync system would try to redeploy the old app indefinitely,
  // additionally the new app ID would get added to the sync profile. This has
  // the potential to flood the user sync profile with an infinite number of
  // apps should the site be serving a random start_url on every navigation.
  if (app_id_ != GenerateAppId(web_application_info_->manifest_id,
                               web_application_info_->start_url)) {
    DestroySelf(ManifestUpdateResult::kAppIdMismatch);
    return;
  }

  if (IsUpdateNeededForManifest()) {
    UpdateAfterWindowsClose();
    return;
  }

  LoadAndCheckIconContents();
}

bool ManifestUpdateTask::IsUpdateNeededForManifest() const {
  DCHECK(web_application_info_.has_value());
  const WebApp* app = registrar_.GetAppById(app_id_);
  DCHECK(app);

  // Allows updating start_url and manifest_id when kWebAppEnableManifestId is
  // enabled. Both fields are allowed to change as long as the app_id generated
  // from them doesn't change.
  if (base::FeatureList::IsEnabled(blink::features::kWebAppEnableManifestId)) {
    if (web_application_info_->manifest_id != app->manifest_id())
      return true;
    if (web_application_info_->start_url != app->start_url())
      return true;
  }

  if (web_application_info_->theme_color != app->theme_color())
    return true;

  if (web_application_info_->scope != app->scope())
    return true;

  if (web_application_info_->display_mode != app->display_mode())
    return true;

  if (web_application_info_->display_override != app->display_mode_override())
    return true;

  // Allow app icon updating for certain apps, or if the existing icons are
  // empty - this means the app icon download during install failed.
  if (AllowUnpromptedIconUpdate(app_id_, registrar_) &&
      web_application_info_->icon_infos != app->icon_infos()) {
    return true;
  }

  if (web_application_info_->shortcuts_menu_item_infos !=
      app->shortcuts_menu_item_infos()) {
    return true;
  }

  if (web_application_info_->share_target != app->share_target())
    return true;

  if (web_application_info_->protocol_handlers != app->protocol_handlers())
    return true;

  if (web_application_info_->url_handlers != app->url_handlers())
    return true;

  if (web_application_info_->note_taking_new_note_url !=
      app->note_taking_new_note_url()) {
    return true;
  }

  if (web_application_info_->capture_links != app->capture_links())
    return true;

  if (os_integration_manager_.IsFileHandlingAPIAvailable(app_id_) &&
      app->file_handlers() != web_application_info_->file_handlers) {
    return true;
  }

  if (web_application_info_->background_color != app->background_color())
    return true;

  if (web_application_info_->manifest_url != app->manifest_url())
    return true;

  if (AllowUnpromptedNameUpdate(app_id_, registrar_) &&
      web_application_info_->title != base::UTF8ToUTF16(app->name())) {
    return true;
  }

  if (web_application_info_->launch_handler != app->launch_handler())
    return true;

  // TODO(crbug.com/1212849): Handle changes to is_storage_isolated.

  // TODO(crbug.com/926083): Check more manifest fields.
  return false;
}

void ManifestUpdateTask::UpdateAfterWindowsClose() {
  DCHECK(stage_ == Stage::kPendingInstallableData ||
         stage_ == Stage::kPendingAppIdentityCheck);
  stage_ = Stage::kPendingWindowsClosed;
  Observe(nullptr);

  ui_manager_.NotifyOnAllAppWindowsClosed(
      app_id_,
      base::BindOnce(&ManifestUpdateTask::OnAllAppWindowsClosed, AsWeakPtr()));
}

void ManifestUpdateTask::LoadAndCheckIconContents() {
  DCHECK_EQ(stage_, Stage::kPendingInstallableData);
  stage_ = Stage::kPendingIconDownload;

  DCHECK(web_application_info_.has_value());
  std::vector<GURL> icon_urls =
      GetValidIconUrlsToDownload(*web_application_info_);
  icon_downloader_.emplace(
      web_contents(), std::move(icon_urls),
      WebAppIconDownloader::Histogram::kForUpdate,
      base::BindOnce(&ManifestUpdateTask::OnIconsDownloaded, AsWeakPtr()));
  icon_downloader_->SkipPageFavicons();
  icon_downloader_->FailAllIfAnyFail();
  icon_downloader_->Start();
}

void ManifestUpdateTask::OnIconsDownloaded(bool success, IconsMap icons_map) {
  DCHECK_EQ(stage_, Stage::kPendingIconDownload);

  if (!success) {
    DestroySelf(ManifestUpdateResult::kIconDownloadFailed);
    return;
  }

  stage_ = Stage::kPendingIconReadFromDisk;
  icon_manager_.ReadAllIcons(
      app_id_, base::BindOnce(&ManifestUpdateTask::OnAllIconsRead, AsWeakPtr(),
                              std::move(icons_map)));
}

void ManifestUpdateTask::OnAllIconsRead(IconsMap downloaded_icons_map,
                                        IconBitmaps disk_icon_bitmaps) {
  DCHECK_EQ(stage_, Stage::kPendingIconReadFromDisk);

  if (disk_icon_bitmaps.empty()) {
    DestroySelf(ManifestUpdateResult::kIconReadFromDiskFailed);
    return;
  }
  DCHECK(web_application_info_.has_value());

  content::WebContents* web_contents = WebContentsObserver::web_contents();
  stage_ = Stage::kPendingAppIdentityCheck;
  Observe(nullptr);

  PopulateOtherIcons(&web_application_info_.value(), downloaded_icons_map);

  if (!AllowUnpromptedNameUpdate(app_id_, registrar_) &&
      !AllowUnpromptedIconUpdate(app_id_, registrar_) &&
      base::FeatureList::IsEnabled(features::kPwaUpdateDialogForNameAndIcon)) {
    // This call populates the |web_application_info_| with all icon bitmap
    // data.
    // If this data does not match what we already have on disk, then an update
    // is necessary.
    // TODO(https://crbug.com/1184911): Reuse this data in the web app install
    // task.
    PopulateProductIcons(&web_application_info_.value(), &downloaded_icons_map);
    IconDiff icon_diff = IsUpdateNeededForIconContents(disk_icon_bitmaps);
    std::u16string old_title =
        base::UTF8ToUTF16(registrar_.GetAppShortName(app_id_));
    std::u16string new_title = web_application_info_->title;
    bool title_change = old_title != new_title;

    if (title_change || icon_diff.changes_detected) {
      SkBitmap* before_icon = nullptr;
      SkBitmap* after_icon = nullptr;
      if (icon_diff.changes_detected) {
        before_icon = &icon_diff.before;
        after_icon = &icon_diff.after;
      } else {
        auto it = disk_icon_bitmaps.any.find(web_app::kWebAppIconSmall);
        if (it != disk_icon_bitmaps.any.end()) {
          before_icon = &it->second;
          after_icon = &it->second;
        }
      }

      if (before_icon != nullptr && after_icon != nullptr) {
        ui_manager_.ShowWebAppIdentityUpdateDialog(
            app_id_, title_change, icon_diff.changes_detected, old_title,
            new_title, *before_icon, *after_icon, web_contents,
            base::BindOnce(&ManifestUpdateTask::OnPostAppIdentityUpdateCheck,
                           AsWeakPtr(), std::move(downloaded_icons_map),
                           std::move(disk_icon_bitmaps)));
        return;
      }
    }
  }

  // App Identity Warning dialog was not needed, proceed with update check.
  OnPostAppIdentityUpdateCheck(downloaded_icons_map, disk_icon_bitmaps,
                               AppIdentityUpdate::kSkipped);
}

void ManifestUpdateTask::OnPostAppIdentityUpdateCheck(
    IconsMap downloaded_icons_map,
    IconBitmaps disk_icon_bitmaps,
    AppIdentityUpdate app_identity_update_allowed) {
  DCHECK_EQ(stage_, Stage::kPendingAppIdentityCheck);
  app_identity_update_allowed_ =
      app_identity_update_allowed == AppIdentityUpdate::kAllowed;
  if (app_identity_update_allowed_) {
    UpdateAfterWindowsClose();
    return;
  }

  // Allow app icon updating for certain apps, or if the existing icons are
  // empty - this means the app icon download during install failed.
  if (AllowUnpromptedIconUpdate(app_id_, registrar_)) {
    // When kPwaUpdateDialogForNameAndIcon is enabled, the FilterAndResizeIcons
    // call has already been made.
    if (!base::FeatureList::IsEnabled(
            features::kPwaUpdateDialogForNameAndIcon)) {
      // This call populates the |web_application_info_| with all icon bitmap
      // data.
      // If this data does not match what we already have on disk, then an
      // update is necessary.
      // TODO(https://crbug.com/1184911): Reuse this data in the web app install
      // task.
      PopulateProductIcons(&web_application_info_.value(),
                           &downloaded_icons_map);
    }

    // TODO: compare in a BEST_EFFORT blocking PostTaskAndReply.
    if (IsUpdateNeededForIconContents(disk_icon_bitmaps).changes_detected) {
      UpdateAfterWindowsClose();
      return;
    }
  }

  icon_manager_.ReadAllShortcutsMenuIcons(
      app_id_, base::BindOnce(&ManifestUpdateTask::OnAllShortcutsMenuIconsRead,
                              AsWeakPtr()));
}

IconDiff ManifestUpdateTask::IsUpdateNeededForIconContents(
    const IconBitmaps& disk_icon_bitmaps) const {
  DCHECK(web_application_info_.has_value());
  return HaveIconBitmapsChanged(disk_icon_bitmaps,
                                web_application_info_->icon_bitmaps);
}

void ManifestUpdateTask::OnAllShortcutsMenuIconsRead(
    ShortcutsMenuIconBitmaps disk_shortcuts_menu_icon_bitmaps) {
  DCHECK_EQ(stage_, Stage::kPendingAppIdentityCheck);

  DCHECK(web_application_info_.has_value());

  if (IsUpdateNeededForShortcutsMenuIconsContents(
          disk_shortcuts_menu_icon_bitmaps)) {
    UpdateAfterWindowsClose();
    return;
  }

  NoManifestUpdateRequired();
}

bool ManifestUpdateTask::IsUpdateNeededForShortcutsMenuIconsContents(
    const ShortcutsMenuIconBitmaps& disk_shortcuts_menu_icon_bitmaps) const {
  DCHECK(web_application_info_.has_value());
  const ShortcutsMenuIconBitmaps& downloaded_shortcuts_menu_icon_bitmaps =
      web_application_info_->shortcuts_menu_icon_bitmaps;
  if (downloaded_shortcuts_menu_icon_bitmaps.size() !=
      disk_shortcuts_menu_icon_bitmaps.size()) {
    return true;
  }

  for (size_t i = 0; i < downloaded_shortcuts_menu_icon_bitmaps.size(); ++i) {
    const IconBitmaps& downloaded_icon_bitmaps =
        downloaded_shortcuts_menu_icon_bitmaps[i];
    const IconBitmaps& disk_icon_bitmaps = disk_shortcuts_menu_icon_bitmaps[i];
    if (HaveIconBitmapsChanged(disk_icon_bitmaps, downloaded_icon_bitmaps)
            .changes_detected)
      return true;
  }

  return false;
}

bool ManifestUpdateTask::IsUpdateNeededForWebAppOriginAssociations() const {
  // Web app origin association update is tied to the manifest update process.
  // If there are url handlers for the current app, associations need to be
  // revalidated.
  DCHECK(web_application_info_.has_value());
  return !web_application_info_->url_handlers.empty();
}

void ManifestUpdateTask::NoManifestUpdateRequired() {
  DCHECK_EQ(stage_, Stage::kPendingAppIdentityCheck);
  stage_ = Stage::kPendingAssociationsUpdate;
  if (!IsUpdateNeededForWebAppOriginAssociations()) {
    DestroySelf(ManifestUpdateResult::kAppUpToDate);
    return;
  }

  os_integration_manager_.UpdateUrlHandlers(
      app_id_,
      base::BindOnce(&ManifestUpdateTask::OnWebAppOriginAssociationsUpdated,
                     AsWeakPtr()));
}

void ManifestUpdateTask::OnWebAppOriginAssociationsUpdated(bool success) {
  DCHECK_EQ(stage_, Stage::kPendingAssociationsUpdate);
  success ? DestroySelf(ManifestUpdateResult::kAppAssociationsUpdated)
          : DestroySelf(ManifestUpdateResult::kAppAssociationsUpdateFailed);
}

void ManifestUpdateTask::OnAllAppWindowsClosed() {
  DCHECK_EQ(stage_, Stage::kPendingWindowsClosed);

  DCHECK(web_application_info_.has_value());

  if (!AllowUnpromptedNameUpdate(app_id_, registrar_) &&
      !app_identity_update_allowed_) {
    // The app's name must not change due to an automatic update, except for
    // default installed apps (that have been vetted).
    // TODO(crbug.com/1088338): Provide a safe way for apps to update their
    // name.
    web_application_info_->title =
        base::UTF8ToUTF16(registrar_.GetAppShortName(app_id_));
  }

  // Preserve the user's choice of form factor to open the app with.
  web_application_info_->user_display_mode =
      registrar_.GetAppUserDisplayMode(app_id_);

  stage_ = Stage::kPendingMaybeReadExistingIcons;
  // If icon updating is disabled, then read the existing icons so they can be
  // populated on the WebApplicationInfo.
  if (AllowUnpromptedIconUpdate(app_id_, registrar_) ||
      app_identity_update_allowed_) {
    OnExistingIconsRead(IconBitmaps());
    return;
  }
  icon_manager_.ReadAllIcons(
      app_id_,
      base::BindOnce(&ManifestUpdateTask::OnExistingIconsRead, AsWeakPtr()));
}

void ManifestUpdateTask::OnExistingIconsRead(IconBitmaps icon_bitmaps) {
  DCHECK_EQ(stage_, Stage::kPendingMaybeReadExistingIcons);

  bool redownload_app_icons = icon_bitmaps.empty();
  if (!redownload_app_icons)
    web_application_info_->icon_bitmaps = std::move(icon_bitmaps);

  stage_ = Stage::kPendingInstallation;
  install_manager_.UpdateWebAppFromInfo(
      app_id_, std::make_unique<WebApplicationInfo>(*web_application_info_),
      /*redownload_app_icons=*/redownload_app_icons,
      base::BindOnce(&ManifestUpdateTask::OnInstallationComplete, AsWeakPtr()));
}

void ManifestUpdateTask::OnInstallationComplete(
    const AppId& app_id,
    InstallResultCode code) {
  DCHECK_EQ(stage_, Stage::kPendingInstallation);

  if (!IsSuccess(code)) {
    DestroySelf(ManifestUpdateResult::kAppUpdateFailed);
    return;
  }

  DCHECK_EQ(app_id_, app_id);
  DCHECK(!IsUpdateNeededForManifest());
  DCHECK_EQ(code, InstallResultCode::kSuccessAlreadyInstalled);

  DestroySelf(ManifestUpdateResult::kAppUpdated);
}

void ManifestUpdateTask::DestroySelf(ManifestUpdateResult result) {
  // Asserts that calling the callback results in |this| getting deleted.
#if DCHECK_IS_ON()
  bool destructor_called = false;
  destructor_called_ptr_ = &destructor_called;
#endif
  std::move(stopped_callback_).Run(*this, result);
#if DCHECK_IS_ON()
  DCHECK(destructor_called);
#endif
}

}  // namespace web_app