// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_LOADER_NAVIGATION_URL_LOADER_DELEGATE_H_
#define CONTENT_BROWSER_LOADER_NAVIGATION_URL_LOADER_DELEGATE_H_

#include <memory>
#include <optional>

#include "content/common/content_export.h"
#include "mojo/public/cpp/bindings/pending_receiver.h"
#include "services/network/public/mojom/early_hints.mojom-forward.h"
#include "services/network/public/mojom/url_loader.mojom.h"
#include "services/network/public/mojom/url_loader_factory.mojom.h"
#include "services/network/public/mojom/url_response_head.mojom.h"
#include "third_party/blink/public/common/navigation/navigation_policy.h"
#include "url/origin.h"

namespace net {
class NetworkAnonymizationKey;
struct RedirectInfo;
}

namespace network {
struct URLLoaderCompletionStatus;
}

namespace content {

class NavigationEarlyHintsManager;
struct NavigationEarlyHintsManagerParams;
struct GlobalRequestID;
struct SubresourceLoaderParams;

// The delegate interface to NavigationURLLoader.
class CONTENT_EXPORT NavigationURLLoaderDelegate {
 public:
  // Conveys information related to Early Hints responses.
  struct CONTENT_EXPORT EarlyHints {
    EarlyHints();
    ~EarlyHints();

    EarlyHints(EarlyHints&& other);
    EarlyHints& operator=(EarlyHints&& other);

    EarlyHints(const EarlyHints& other) = delete;
    EarlyHints& operator=(const EarlyHints& other) = delete;

    // True when at least one preload or preconnect Link header was received
    // during a main frame navigation.
    bool was_resource_hints_received = false;
    // Non-null when at least one preload is actually requested.
    std::unique_ptr<NavigationEarlyHintsManager> manager;
  };

  NavigationURLLoaderDelegate(const NavigationURLLoaderDelegate&) = delete;
  NavigationURLLoaderDelegate& operator=(const NavigationURLLoaderDelegate&) =
      delete;

  // Called when the request is redirected. Call FollowRedirect to continue
  // processing the request.
  //
  // |network_anonymization_key| is the NetworkAnonymizationKey associated with
  // the request that was redirected, not the one that will be used if the
  // redirect is followed.
  virtual void OnRequestRedirected(
      const net::RedirectInfo& redirect_info,
      const net::NetworkAnonymizationKey& network_anonymization_key,
      network::mojom::URLResponseHeadPtr response) = 0;

  // Called when the request receives its response. No further calls will be
  // made to the delegate. The response body can be retrieved by implementing an
  // URLLoaderClient and binding the |url_loader_client_endpoints|.
  // |navigation_data| is passed to the NavigationHandle.
  // |subresource_loader_params| is used in the network service only for passing
  // necessary info to create a custom subresource loader in the renderer
  // process if the navigated context is controlled by a request interceptor.
  //
  // |is_download| is true if the request must be downloaded, if it isn't
  // disallowed.
  //
  // Invoking this method will delete the URLLoader, so it needs to take all
  // arguments by value.
  virtual void OnResponseStarted(
      network::mojom::URLLoaderClientEndpointsPtr url_loader_client_endpoints,
      network::mojom::URLResponseHeadPtr response_head,
      mojo::ScopedDataPipeConsumerHandle response_body,
      GlobalRequestID request_id,
      bool is_download,
      net::NetworkAnonymizationKey network_anonymization_key,
      SubresourceLoaderParams subresource_loader_params,
      EarlyHints early_hints) = 0;

  // Called if the request fails before receving a response. Specific
  // fields which are used: |status.error_code| holds the error code
  // for the failure; |status.extended_error_code| holds details if
  // available; |status.exists_in_cache| indicates a stale cache
  // entry; |status.ssl_info| is available when |status.error_code| is
  // a certificate error.
  virtual void OnRequestFailed(
      const network::URLLoaderCompletionStatus& status) = 0;

  // Creates parameters to construct NavigationEarlyHintsManager. Returns
  // std::nullopt when this delegate cannot create parameters.
  virtual std::optional<NavigationEarlyHintsManagerParams>
  CreateNavigationEarlyHintsManagerParams(
      const network::mojom::EarlyHints& early_hints) = 0;

  // Only for testing purpose (https://crbug.com/434182226).
  // In non-test cases, use `OnRequestRedirected()` instead, and this method
  // must do nothing and return `false`.
  //
  // Called when `NavigationURLLoaderImpl::OnReceiveRedirect()` is called.
  // When the return value is `true` (which is only allowed in tests),
  // `head->parsed_headers` is cleared to enforce and test the async
  // `ParseHeaders()` path.
  virtual bool ShouldClearParsedHeadersOnTestReceiveRedirect() = 0;

 protected:
  NavigationURLLoaderDelegate() {}
  virtual ~NavigationURLLoaderDelegate() {}
};

}  // namespace content

#endif  // CONTENT_BROWSER_LOADER_NAVIGATION_URL_LOADER_DELEGATE_H_