// Copyright 2015 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_RENDERER_HOST_FRAME_NAVIGATION_ENTRY_H_
#define CONTENT_BROWSER_RENDERER_HOST_FRAME_NAVIGATION_ENTRY_H_

#include <stdint.h>

#include <optional>

#include "base/memory/ref_counted.h"
#include "content/browser/renderer_host/policy_container_host.h"
#include "content/browser/site_instance_impl.h"
#include "content/common/content_export.h"
#include "content/public/common/bindings_policy.h"
#include "content/public/common/referrer.h"
#include "services/network/public/cpp/shared_url_loader_factory.h"
#include "third_party/blink/public/common/page_state/page_state.h"
#include "url/gurl.h"
#include "url/origin.h"

namespace network {
class ResourceRequestBody;
}

namespace content {

// Represents a session history item for a particular frame.  It is matched with
// corresponding FrameTreeNodes using unique name (or by the root position).
// There is a tree of FrameNavigationEntries in each NavigationEntry, one per
// frame.
//
// This class is refcounted and can be shared across multiple NavigationEntries.
// Each RenderFrameHost also keeps a scoped_refptr to its last committed
// FrameNavigationEntry, to accurately track its current state in cases when the
// last committed NavigationEntry may not match (e.g., when missing the
// relevant FrameNavigationEntry or during a history navigation targeting
// multiple frames while only some have committed.)
class CONTENT_EXPORT FrameNavigationEntry
    : public base::RefCounted<FrameNavigationEntry> {
 public:
  FrameNavigationEntry(
      const std::string& frame_unique_name,
      int64_t item_sequence_number,
      int64_t document_sequence_number,
      const std::string& navigation_api_key,
      scoped_refptr<SiteInstanceImpl> site_instance,
      scoped_refptr<SiteInstanceImpl> source_site_instance,
      const GURL& url,
      const std::optional<url::Origin>& origin,
      const Referrer& referrer,
      const std::optional<url::Origin>& initiator_origin,
      const std::optional<GURL>& initiator_base_url,
      const std::vector<GURL>& redirect_chain,
      const blink::PageState& page_state,
      const std::string& method,
      int64_t post_id,
      scoped_refptr<network::SharedURLLoaderFactory> blob_url_loader_factory,
      std::unique_ptr<PolicyContainerPolicies> policy_container_policies,
      bool protect_url_in_navigation_api);

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

  // Creates a copy of this FrameNavigationEntry that can be modified
  // independently from the original.
  scoped_refptr<FrameNavigationEntry> Clone() const;

  // Updates all the members of this entry.
  void UpdateEntry(
      const std::string& frame_unique_name,
      int64_t item_sequence_number,
      int64_t document_sequence_number,
      const std::string& navigation_api_key,
      SiteInstanceImpl* site_instance,
      scoped_refptr<SiteInstanceImpl> source_site_instance,
      const GURL& url,
      const std::optional<url::Origin>& origin,
      const Referrer& referrer,
      const std::optional<url::Origin>& initiator_origin,
      const std::optional<GURL>& initiator_base_url,
      const std::vector<GURL>& redirect_chain,
      const blink::PageState& page_state,
      const std::string& method,
      int64_t post_id,
      scoped_refptr<network::SharedURLLoaderFactory> blob_url_loader_factory,
      std::unique_ptr<PolicyContainerPolicies> policy_container_policies,
      bool protect_url_in_navigation_api);

  // The unique name of the frame this entry is for.  This is a stable name for
  // the frame based on its position in the tree and relation to other named
  // frames, which does not change after cross-process navigations or restores.
  // Only the main frame can have an empty name.
  //
  // This is unique relative to other frames in the same page, but not among
  // other pages (i.e., not globally unique).
  const std::string& frame_unique_name() const { return frame_unique_name_; }
  void set_frame_unique_name(const std::string& frame_unique_name) {
    frame_unique_name_ = frame_unique_name;
  }

  // Keeps track of where this entry belongs in the frame's session history.
  // The item sequence number identifies each stop in the back/forward history
  // and is globally unique.  The document sequence number increments for each
  // new document and is also globally unique.  In-page navigations get a new
  // item sequence number but the same document sequence number.  These numbers
  // should not change once assigned.
  void set_item_sequence_number(int64_t item_sequence_number);
  int64_t item_sequence_number() const { return item_sequence_number_; }
  void set_document_sequence_number(int64_t document_sequence_number);
  int64_t document_sequence_number() const { return document_sequence_number_; }

  // Identifies a "slot" in the frame's session history for the
  // window.navigation API.
  void set_navigation_api_key(const std::string& navigation_api_key);
  const std::string& navigation_api_key() const { return navigation_api_key_; }

  // The SiteInstance, as assigned at commit time, responsible for rendering
  // this frame.  All frames sharing a SiteInstance must live in the same
  // process.  This is a refcounted pointer that keeps the SiteInstance (not
  // necessarily the process) alive as long as this object remains in the
  // session history.
  SiteInstanceImpl* site_instance() const { return site_instance_.get(); }

  // The |source_site_instance| is used to identify the SiteInstance of the
  // frame that initiated the navigation. It is present only for
  // renderer-initiated navigations and is cleared once the navigation has
  // committed.
  void set_source_site_instance(
      scoped_refptr<SiteInstanceImpl> source_site_instance) {
    source_site_instance_ = std::move(source_site_instance);
  }
  SiteInstanceImpl* source_site_instance() const {
    return source_site_instance_.get();
  }

  // The actual URL loaded in the frame.  This is in contrast to the virtual
  // URL, which is shown to the user.
  void set_url(const GURL& url) { url_ = url; }
  const GURL& url() const { return url_; }

  // The referring URL.  Can be empty.
  void set_referrer(const Referrer& referrer) { referrer_ = referrer; }
  const Referrer& referrer() const { return referrer_; }

  // The origin that initiated the original navigation.  std::nullopt means
  // that the original navigation was browser-initiated (e.g. initiated from a
  // trusted surface like the omnibox or the bookmarks bar).
  const std::optional<url::Origin>& initiator_origin() const {
    return initiator_origin_;
  }

  // The base url of the initiator of the navigation. This is only set if the
  // url is about:blank or about:srcdoc.
  const std::optional<GURL>& initiator_base_url() const {
    return initiator_base_url_;
  }

  // The origin of the document the frame has committed. It is optional, since
  // pending entries do not have an origin associated with them and the real
  // origin is set at commit time.
  void set_committed_origin(const url::Origin& origin) {
    committed_origin_ = origin;
  }
  const std::optional<url::Origin>& committed_origin() const {
    return committed_origin_;
  }

  // The redirect chain traversed during this frame navigation, from the initial
  // redirecting URL to the final non-redirecting current URL.
  void set_redirect_chain(const std::vector<GURL>& redirect_chain) {
    redirect_chain_ = redirect_chain;
  }
  const std::vector<GURL>& redirect_chain() const { return redirect_chain_; }

  void SetPageState(const blink::PageState& page_state);
  const blink::PageState& page_state() const { return page_state_; }

  // Remember the set of bindings granted to this FrameNavigationEntry at the
  // time of commit, to ensure that we do not grant it additional bindings if we
  // navigate back to it in the future.  This can only be changed once.
  // bindings() will return nullopt before the bindings are set.
  void SetBindings(BindingsPolicySet bindings);
  std::optional<BindingsPolicySet> bindings() const { return bindings_; }

  // The HTTP method used to navigate.
  const std::string& method() const { return method_; }
  void set_method(const std::string& method) { method_ = method; }

  // Returns true if the HTTP method was POST.
  bool get_has_post_data() { return method() == "POST"; }

  // The id of the post corresponding to this navigation or -1 if the
  // navigation was not a POST.
  int64_t post_id() const { return post_id_; }
  void set_post_id(int64_t post_id) { post_id_ = post_id; }

  // The data sent during a POST navigation. Returns nullptr if the navigation
  // is not a POST.
  scoped_refptr<network::ResourceRequestBody> GetPostData(
      std::string* content_type) const;

  // The policy container policies for this entry. This is needed for local
  // schemes, since for them the policy container was inherited by the creator,
  // while for network schemes we can reconstruct the policy container by
  // parsing the network response.
  void set_policy_container_policies(
      std::unique_ptr<PolicyContainerPolicies> policies) {
    policy_container_policies_ = std::move(policies);
  }
  const PolicyContainerPolicies* policy_container_policies() const {
    return policy_container_policies_.get();
  }

  // Optional URLLoaderFactory to facilitate blob URL loading.
  scoped_refptr<network::SharedURLLoaderFactory> blob_url_loader_factory()
      const {
    return blob_url_loader_factory_;
  }
  void set_blob_url_loader_factory(
      scoped_refptr<network::SharedURLLoaderFactory> factory) {
    blob_url_loader_factory_ = std::move(factory);
  }

  bool protect_url_in_navigation_api() {
    return protect_url_in_navigation_api_;
  }
  void set_protect_url_in_navigation_api(bool protect) {
    protect_url_in_navigation_api_ = protect;
  }

  void set_item_sequence_number_for_testing(int64_t item_sequence_number) {
    item_sequence_number_ = item_sequence_number;
  }

 private:
  friend class base::RefCounted<FrameNavigationEntry>;
  virtual ~FrameNavigationEntry();

  // WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
  // Add all new fields to |UpdateEntry|.
  // TODO(creis): These fields have implications for session restore.  This is
  // currently managed by NavigationEntry, but the logic will move here.
  // WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING

  // See the accessors above for descriptions.
  std::string frame_unique_name_;

  // sequence numbers and the navigation API key are also stored in
  // |page_state_|. When SetPageState() is called as part of a restore, it also
  // initializes these.
  int64_t item_sequence_number_;
  int64_t document_sequence_number_;
  std::string navigation_api_key_;

  // TODO(nasko, creis): The SiteInstance of a FrameNavigationEntry should
  // not change once it has been assigned.  See https://crbug.com/849430.
  scoped_refptr<SiteInstanceImpl> site_instance_;
  // This member is cleared at commit time and is not persisted.
  scoped_refptr<SiteInstanceImpl> source_site_instance_;
  GURL url_;
  // For a committed navigation, holds the origin of the resulting document.
  // TODO(nasko): This should be possible to calculate at ReadyToCommit time
  // and verified when receiving the DidCommit IPC.
  std::optional<url::Origin> committed_origin_;
  Referrer referrer_;
  std::optional<url::Origin> initiator_origin_;
  std::optional<GURL> initiator_base_url_;
  // This is used when transferring a pending entry from one process to another.
  // We also send the main frame's redirect chain through session sync for
  // offline analysis.
  // It is preserved after commit but should not be persisted.
  std::vector<GURL> redirect_chain_;
  // TODO(creis): Change this to FrameState.
  blink::PageState page_state_;
  // TODO(creis): Persist bindings_. https://crbug.com/40076915.
  std::optional<BindingsPolicySet> bindings_;
  std::string method_;
  int64_t post_id_;
  scoped_refptr<network::SharedURLLoaderFactory> blob_url_loader_factory_;

  // TODO(crbug.com/40053667): Persist these policies.
  std::unique_ptr<PolicyContainerPolicies> policy_container_policies_;

  // If the document represented by this FNE hid its full url from appearing
  // in a referrer via a "no-referrer" or "origin" referrer policy, this URL
  // will be hidden from navigation API history entries as well.
  bool protect_url_in_navigation_api_;
};

}  // namespace content

#endif  // CONTENT_BROWSER_RENDERER_HOST_FRAME_NAVIGATION_ENTRY_H_