// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "components/page_info/core/about_this_site_service.h"

#include "base/feature_list.h"
#include "base/metrics/histogram_functions.h"
#include "components/optimization_guide/core/hints/hints_processing_util.h"
#include "components/optimization_guide/core/hints/optimization_guide_decision.h"
#include "components/optimization_guide/core/hints/optimization_metadata.h"
#include "components/page_info/core/about_this_site_validation.h"
#include "components/page_info/core/features.h"
#include "components/page_info/core/proto/about_this_site_metadata.pb.h"
#include "components/search/search.h"
#include "components/search_engines/template_url_service.h"
#include "net/base/url_util.h"
#include "services/metrics/public/cpp/ukm_builders.h"
#include "services/metrics/public/cpp/ukm_recorder.h"
#include "url/gurl.h"

namespace page_info {
namespace {
using AboutThisSiteStatus = about_this_site_validation::AboutThisSiteStatus;
using AboutThisSiteInteraction = AboutThisSiteService::AboutThisSiteInteraction;
using OptimizationGuideDecision = optimization_guide::OptimizationGuideDecision;

void RecordAboutThisSiteInteraction(AboutThisSiteInteraction interaction) {
  base::UmaHistogramEnumeration("Security.PageInfo.AboutThisSiteInteraction",
                                interaction);
}

}  // namespace

AboutThisSiteService::AboutThisSiteService(
    optimization_guide::OptimizationGuideDecider* optimization_guide_decider,
    bool is_off_the_record,
    PrefService* prefs,
    TemplateURLService* template_url_service)
    : optimization_guide_decider_(optimization_guide_decider),
      is_off_the_record_(is_off_the_record),
      prefs_(prefs),
      template_url_service_(template_url_service) {
  if (optimization_guide_decider_) {
    optimization_guide_decider_->RegisterOptimizationTypes(
        {optimization_guide::proto::ABOUT_THIS_SITE});
  }
}

std::optional<proto::SiteInfo> AboutThisSiteService::GetAboutThisSiteInfo(
    const GURL& url,
    ukm::SourceId source_id,
    const TabHelper* tab_helper) const {
  if (!search::DefaultSearchProviderIsGoogle(template_url_service_)) {
    RecordAboutThisSiteInteraction(
        AboutThisSiteInteraction::kNotShownNonGoogleDSE);

    return std::nullopt;
  }

  if (!optimization_guide::IsValidURLForURLKeyedHint(url)) {
    RecordAboutThisSiteInteraction(
        AboutThisSiteInteraction::kNotShownLocalHost);
    return std::nullopt;
  }

  if (!IsOptimizationGuideAllowed()) {
    RecordAboutThisSiteInteraction(
        AboutThisSiteInteraction::kNotShownOptimizationGuideNotAllowed);
    return std::nullopt;
  }
  std::optional<proto::AboutThisSiteMetadata> about_this_site_metadata;
  optimization_guide::OptimizationGuideDecision decision;
  if (tab_helper) {
    std::tie(decision, about_this_site_metadata) =
        tab_helper->GetAboutThisSiteMetadata();
  } else {
    optimization_guide::OptimizationMetadata metadata;
    decision = CanApplyOptimization(url, &metadata);
    about_this_site_metadata =
        metadata.ParsedMetadata<proto::AboutThisSiteMetadata>();
  }

  AboutThisSiteStatus status =
      decision == OptimizationGuideDecision::kUnknown
          ? AboutThisSiteStatus::kUnknown
          : about_this_site_validation::ValidateMetadata(
                about_this_site_metadata);
  base::UmaHistogramEnumeration("Security.PageInfo.AboutThisSiteStatus",
                                status);
  RecordAboutThisSiteInteraction(
      status == AboutThisSiteStatus::kValid
          ? (about_this_site_metadata->site_info().has_description()
                 ? AboutThisSiteInteraction::kShownWithDescription
                 : AboutThisSiteInteraction::kShownWithoutDescription)
          : AboutThisSiteInteraction::kNotShown);

  ukm::builders::AboutThisSiteStatus(source_id)
      .SetStatus(static_cast<int>(status))
      .Record(ukm::UkmRecorder::Get());
  if (status == AboutThisSiteStatus::kValid) {
    if (about_this_site_metadata->site_info().has_more_about()) {
      // Append a context parameter to identify that this URL is visited from
      // Chrome. If we add more UI surfaces that can open this URL, we should
      // pass in different context parameters.
      proto::MoreAbout* more_about =
          about_this_site_metadata->mutable_site_info()->mutable_more_about();
      GURL more_about_url =
          net::AppendQueryParameter(GURL(more_about->url()), "ctx", "chrome");
      more_about->set_url(more_about_url.spec());
    }
    return about_this_site_metadata->site_info();
  }

  if (kShowSampleContent.Get()) {
    page_info::proto::SiteInfo site_info;
    if (url == GURL("https://example.com")) {
      site_info.mutable_more_about()->set_url(
          "https://example.com/#more-about");
      return site_info;
    }

    if (url == GURL("https://permission.site")) {
      auto* description = site_info.mutable_description();
      description->set_name("Permission Site");
      description->set_subtitle("Testing site");
      description->set_description(
          "A site containing test buttons for various browser APIs, in order"
          " to trigger permission dialogues and similar UI in modern "
          "browsers.");
      description->mutable_source()->set_url("https://permission.site.com");
      description->mutable_source()->set_label("Permission Site");
      return site_info;
    }
  }

  return std::nullopt;
}

// static
GURL AboutThisSiteService::CreateMoreAboutUrlForNavigation(const GURL& url) {
  GURL more_about_url = GURL("https://www.google.com/search");

  // Strip paths of invalid urls
  const std::string url_spec =
      optimization_guide::IsValidURLForURLKeyedHint(url)
          ? url.spec()
          : url.GetWithEmptyPath().spec();

  more_about_url =
      net::AppendQueryParameter(more_about_url, "q", "About " + url_spec);
  more_about_url = net::AppendQueryParameter(more_about_url, "tbm", "ilp");
  more_about_url =
      net::AppendQueryParameter(more_about_url, "ctx", "chrome_nav");

  return more_about_url;
}

// static
void AboutThisSiteService::OnAboutThisSiteRowClicked(bool with_description) {
  RecordAboutThisSiteInteraction(
      with_description ? AboutThisSiteInteraction::kClickedWithDescription
                       : AboutThisSiteInteraction::kClickedWithoutDescription);
}

// static
void AboutThisSiteService::OnOpenedDirectlyFromSidePanel() {
  RecordAboutThisSiteInteraction(
      AboutThisSiteInteraction::kOpenedDirectlyFromSidePanel);
}

// static
void AboutThisSiteService::OnSameTabNavigation() {
  RecordAboutThisSiteInteraction(AboutThisSiteInteraction::kSameTabNavigation);
}

base::WeakPtr<AboutThisSiteService> AboutThisSiteService::GetWeakPtr() {
  return weak_ptr_factory_.GetWeakPtr();
}

AboutThisSiteService::~AboutThisSiteService() = default;

bool AboutThisSiteService::IsOptimizationGuideAllowed() const {
  return optimization_guide::IsUserPermittedToFetchFromRemoteOptimizationGuide(
      is_off_the_record_, prefs_);
}

optimization_guide::OptimizationGuideDecision
AboutThisSiteService::CanApplyOptimization(
    const GURL& url,
    optimization_guide::OptimizationMetadata* optimization_metadata) const {
  if (!IsOptimizationGuideAllowed()) {
    return optimization_guide::OptimizationGuideDecision::kUnknown;
  }
  return optimization_guide_decider_->CanApplyOptimization(
      url, optimization_guide::proto::ABOUT_THIS_SITE, optimization_metadata);
}

}  // namespace page_info