// Copyright 2025 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/segmentation_platform/embedder/home_modules/default_browser_promo_ephemeral_module.h"

#include "base/containers/fixed_flat_set.h"
#include "base/feature_list.h"
#include "components/prefs/pref_registry_simple.h"
#include "components/prefs/pref_service.h"
#include "components/segmentation_platform/embedder/home_modules/constants.h"
#include "components/segmentation_platform/embedder/home_modules/ephemeral_module_utils.h"
#include "components/segmentation_platform/public/features.h"

namespace segmentation_platform::home_modules {

constexpr char kIsDefaultBrowserSignalKey[] = "is_default_browser_chrome_ios";

namespace {

// Impression counter for the Default Browser promo ephemeral module.
const char kDefaultBrowserPromoEphemeralModuleImpressionCounterPref[] =
    "ephemeral_pref_counter.default_browser_promo_ephemeral_module_counter";

// Defines the signals that must all evaluate to false for
// `DefaultBrowserPromoEphemeralModule` to be shown.
constexpr auto kDisqualifyingSignals =
    base::MakeFixedFlatSet<std::string_view>({
        segmentation_platform::kIsNewUser,
        kIsDefaultBrowserSignalKey,
    });

}  // namespace

DefaultBrowserPromoEphemeralModule::DefaultBrowserPromoEphemeralModule()
    : CardSelectionInfo(kDefaultBrowserPromoEphemeralModule) {}

// static
void DefaultBrowserPromoEphemeralModule::RegisterProfilePrefs(
    PrefRegistrySimple* registry) {
  registry->RegisterIntegerPref(
      kDefaultBrowserPromoEphemeralModuleImpressionCounterPref, 0);
}

std::map<SignalKey, FeatureQuery>
DefaultBrowserPromoEphemeralModule::GetInputs() {
  return {
      {segmentation_platform::kIsNewUser,
       CreateFeatureQueryFromCustomInputName(
           segmentation_platform::kIsNewUser)},
      {kIsDefaultBrowserSignalKey,
       CreateFeatureQueryFromCustomInputName(kIsDefaultBrowserChromeIos)},
  };
}

CardSelectionInfo::ShowResult
DefaultBrowserPromoEphemeralModule::ComputeCardResult(
    const CardSelectionSignals& signals) const {
  // Check for a forced `ShowResult`.
  std::optional<CardSelectionInfo::ShowResult> forced_result =
      GetForcedEphemeralModuleShowResult();

  // If forced to show/hide and the module label matches the current module,
  // return true/false accordingly.
  if (forced_result.has_value() &&
      forced_result.value().result_label.has_value() &&
      IsModuleLabel(forced_result.value().result_label.value())) {
    return forced_result.value();
  }

  CardSelectionInfo::ShowResult result;
  result.result_label = kDefaultBrowserPromoEphemeralModule;

  // Prevent the card from showing if the user is a new user or they have
  // Chrome set as their default browser.
  for (const auto& signal : kDisqualifyingSignals) {
    std::optional<float> currentSignal = signals.GetSignal(std::string(signal));

    // All signals must have a value and must evaluate to false. Otherwise, the
    // card will not be shown.
    if (!currentSignal.has_value() || currentSignal.value() > 0) {
      return ShowResult(EphemeralHomeModuleRank::kNotShown);
    }
  }

  // Show the card if the user is not a new user and they do not have Chrome
  // set as their default browser.
  result.position = EphemeralHomeModuleRank::kTop;
  return result;
}

void DefaultBrowserPromoEphemeralModule::OnShow(PrefService* profile_prefs,
                                                PrefService* local_state) {
  int freshness_impression_count = profile_prefs->GetInteger(
      kDefaultBrowserPromoEphemeralModuleImpressionCounterPref);

  profile_prefs->SetInteger(
      kDefaultBrowserPromoEphemeralModuleImpressionCounterPref,
      freshness_impression_count + 1);
}

bool DefaultBrowserPromoEphemeralModule::IsModuleLabel(std::string_view label) {
  return label == kDefaultBrowserPromoEphemeralModule;
}

bool DefaultBrowserPromoEphemeralModule::IsEnabled(PrefService* profile_prefs) {
  if (!base::FeatureList::IsEnabled(features::kDefaultBrowserMagicStackIos)) {
    return false;
  }

  std::optional<CardSelectionInfo::ShowResult> forced_result =
      GetForcedEphemeralModuleShowResult();

  if (forced_result.has_value() &&
      forced_result.value().result_label.has_value() &&
      IsModuleLabel(forced_result.value().result_label.value())) {
    return forced_result.value().position == EphemeralHomeModuleRank::kTop;
  }

  int impression_count = profile_prefs->GetInteger(
      kDefaultBrowserPromoEphemeralModuleImpressionCounterPref);

  return impression_count <
         features::kMaxDefaultBrowserMagicStackIosImpressions.Get();
}

}  // namespace segmentation_platform::home_modules