// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "chrome/browser/content_settings/mixed_content_settings_tab_helper.h"

#include "components/content_settings/common/content_settings_agent.mojom.h"
#include "content/public/browser/back_forward_cache.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/navigation_handle.h"
#include "content/public/browser/render_frame_host.h"
#include "content/public/browser/site_instance.h"
#include "mojo/public/cpp/bindings/associated_remote.h"
#include "third_party/blink/public/common/associated_interfaces/associated_interface_provider.h"

using content::BrowserThread;
using content::RenderFrameHost;
using content::WebContents;

MixedContentSettingsTabHelper::MixedContentSettingsTabHelper(WebContents* tab)
    : content::WebContentsObserver(tab),
      content::WebContentsUserData<MixedContentSettingsTabHelper>(*tab) {
  if (!tab->HasOpener())
    return;

  // Note: using the opener WebContents to override these values only works
  // because in Chrome these settings are maintained at the tab level instead of
  // at the frame level as Blink does.
  MixedContentSettingsTabHelper* opener_settings =
      MixedContentSettingsTabHelper::FromWebContents(
          WebContents::FromRenderFrameHost(tab->GetOpener()));
  if (opener_settings &&
      opener_settings->IsRunningInsecureContentAllowed(*tab->GetOpener())) {
    AllowRunningOfInsecureContent(*tab->GetPrimaryMainFrame());
  }
}

MixedContentSettingsTabHelper::~MixedContentSettingsTabHelper() = default;

void MixedContentSettingsTabHelper::AllowRunningOfInsecureContent(
    RenderFrameHost& render_frame_host) {
  DCHECK(!render_frame_host.IsNestedWithinFencedFrame());
  auto* main_frame = render_frame_host.GetOutermostMainFrame();
  auto [it, inserted] = settings_.try_emplace(main_frame->GetSiteInstance());
  if (inserted) {
    it->second = std::make_unique<SiteSettings>(main_frame);
  }
  it->second->AllowRunningOfInsecureContent();
}

void MixedContentSettingsTabHelper::RenderFrameCreated(
    content::RenderFrameHost* render_frame_host) {
  if (!IsRunningInsecureContentAllowed(*render_frame_host))
    return;

  // Fenced Frames should never allow insecure content.
  DCHECK(!render_frame_host->IsNestedWithinFencedFrame());
  mojo::AssociatedRemote<content_settings::mojom::ContentSettingsAgent> agent;
  render_frame_host->GetRemoteAssociatedInterfaces()->GetInterface(&agent);
  agent->SetAllowRunningInsecureContent();

  if (!render_frame_host->GetParentOrOuterDocument()) {
    // A new main RenderFrames is using the SiteSettings for this SiteInstance.
    settings_[render_frame_host->GetSiteInstance()]
        ->IncrementRenderFrameCount();
  }
}

void MixedContentSettingsTabHelper::RenderFrameDeleted(RenderFrameHost* frame) {
  if (frame->GetParentOrOuterDocument()) {
    return;
  }
  if (auto it = settings_.find(frame->GetSiteInstance());
      it != settings_.end()) {
    SiteSettings* settings = it->second.get();
    // The deleted RenderFrame is no longer using the SiteSettings.
    settings->DecrementRenderFrameCount();
    if (settings->render_frame_count() == 0) {
      // No RenderFrame is using the SiteSettings.
      settings_.erase(it);
    }
  }
}

bool MixedContentSettingsTabHelper::IsRunningInsecureContentAllowed(
    RenderFrameHost& render_frame_host) {
  // If render_frame_host is not nested in a Fenced Frame then the
  // InsecureContent of the outermost main frame applies. If render_frame_host
  // is a frame that is the root of a Fenced Frame or is nested inside a Fenced
  // Frame the Insecure Content setting is ignored.
  if (render_frame_host.IsNestedWithinFencedFrame())
    return false;
  auto setting_it = settings_.find(
      render_frame_host.GetOutermostMainFrame()->GetSiteInstance());
  if (setting_it == settings_.end())
    return false;
  return setting_it->second->is_running_insecure_content_allowed();
}

MixedContentSettingsTabHelper::SiteSettings::SiteSettings(
    RenderFrameHost* main_frame_host) {
  DCHECK(!main_frame_host->GetParentOrOuterDocument());
  if (main_frame_host->IsRenderFrameLive()) {
    // There is already a live RenderFrame using `main_frame_host`'s
    // SiteInstance, so set the RenderFrame count to 1, so that we will decrease
    // the RenderFrame count correctly when this RenderFrame gets deleted.
    render_frame_count_ = 1;
  }
}

void MixedContentSettingsTabHelper::SiteSettings::
    AllowRunningOfInsecureContent() {
  DCHECK_CURRENTLY_ON(BrowserThread::UI);
  is_running_insecure_content_allowed_ = true;
}

void MixedContentSettingsTabHelper::SiteSettings::IncrementRenderFrameCount() {
  render_frame_count_++;
}

void MixedContentSettingsTabHelper::SiteSettings::DecrementRenderFrameCount() {
  DCHECK_GT(render_frame_count_, 0);
  render_frame_count_--;
}

WEB_CONTENTS_USER_DATA_KEY_IMPL(MixedContentSettingsTabHelper);