text: // Copyright 2020 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.
  
  #ifndef CHROME_BROWSER_UI_WEBUI_NEW_TAB_PAGE_UNTRUSTED_SOURCE_H_
  #define CHROME_BROWSER_UI_WEBUI_NEW_TAB_PAGE_UNTRUSTED_SOURCE_H_
  
  #include <string>
  #include <vector>
  
  #include "base/scoped_observation.h"
  #include "chrome/browser/new_tab_page/one_google_bar/one_google_bar_service.h"
  #include "chrome/browser/new_tab_page/one_google_bar/one_google_bar_service_observer.h"
  #include "content/public/browser/url_data_source.h"
  
  class Profile;
  
  // Serves chrome-untrusted://new-tab-page/* sources which can return content
  // from outside the chromium codebase. The chrome-untrusted://new-tab-page/*
  // sources can only be embedded in the chrome://new-tab-page by using an
  // <iframe>.
  //
  // Offers the following helpers to embed content into chrome://new-tab-page in a
  // generalized way:
  //   * chrome-untrusted://new-tab-page/image?<url>: Behaves like an img element
  //       with src set to <url>.
  //   * chrome-untrusted://new-tab-page/background_image?<url>: Behaves like an
  //       element that has <url> set as the background image, such that the image
  //       will cover the entire element.
  //   * chrome-untrusted://new-tab-page/custom_background_image?<params>: Similar
  //       to background_image but allows for custom styling. <params> are of the
  //       form <key>=<value>. The following keys are supported:
  //         * url:       background image URL.
  //         * url2x:     (optional) URL to a higher res background image.
  //         * size:      (optional) CSS background-size property.
  //         * repeatX:   (optional) CSS background-repeat-x property.
  //         * repeatY:   (optional) CSS background-repeat-y property.
  //         * positionX: (optional) CSS background-position-x property.
  //         * positionY: (optional) CSS background-position-y property.
  //   Each of those helpers only accept URLs with HTTPS or chrome-untrusted:.
  class UntrustedSource : public content::URLDataSource,
                          public OneGoogleBarServiceObserver {
   public:
    explicit UntrustedSource(Profile* profile);
    ~UntrustedSource() override;
    UntrustedSource(const UntrustedSource&) = delete;
    UntrustedSource& operator=(const UntrustedSource&) = delete;
  
    // content::URLDataSource:
    std::string GetContentSecurityPolicy(
        network::mojom::CSPDirectiveName directive) override;
    std::string GetSource() override;
    void StartDataRequest(
        const GURL& url,
        const content::WebContents::Getter& wc_getter,
        content::URLDataSource::GotDataCallback callback) override;
    std::string GetMimeType(const std::string& path) override;
    bool AllowCaching() override;
    bool ShouldReplaceExistingSource() override;
    bool ShouldServeMimeTypeAsContentTypeHeader() override;
    bool ShouldServiceRequest(const GURL& url,
                              content::BrowserContext* browser_context,
                              int render_process_id) override;
  
   private:
    // OneGoogleBarServiceObserver:
    void OnOneGoogleBarDataUpdated() override;
    void OnOneGoogleBarServiceShuttingDown() override;
  
    void ServeBackgroundImage(const GURL& url,
                              const GURL& url_2x,
                              const std::string& size,
                              const std::string& repeat_x,
                              const std::string& repeat_y,
                              const std::string& position_x,
                              const std::string& position_y,
                              content::URLDataSource::GotDataCallback callback);
  
    std::vector<content::URLDataSource::GotDataCallback>
        one_google_bar_callbacks_;
    OneGoogleBarService* one_google_bar_service_;
    base::ScopedObservation<OneGoogleBarService, OneGoogleBarServiceObserver>
        one_google_bar_service_observation_{this};
    absl::optional<base::TimeTicks> one_google_bar_load_start_time_;
    Profile* profile_;
  };
  
  #endif  // CHROME_BROWSER_UI_WEBUI_NEW_TAB_PAGE_UNTRUSTED_SOURCE_H_
  