// Copyright 2022 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/commerce/core/metrics/scheduled_metrics_manager.h"

#include <vector>

#include "base/functional/bind.h"
#include "base/metrics/histogram_functions.h"
#include "base/task/sequenced_task_runner.h"
#include "components/commerce/core/feature_utils.h"
#include "components/commerce/core/pref_names.h"
#include "components/commerce/core/price_tracking_utils.h"
#include "components/commerce/core/shopping_service.h"
#include "components/commerce/core/subscriptions/commerce_subscription.h"
#include "components/prefs/pref_service.h"

namespace commerce::metrics {

namespace {
const base::TimeDelta kDailyInterval = base::Days(1);
}  // namespace

const char kPriceNotificationEmailHistogramName[] =
    "Commerce.PriceTracking.EmailNotificationsEnabled";
const char kTrackedProductCountHistogramName[] =
    "Commerce.PriceTracking.PriceTrackedProductCount";

ScheduledMetricsManager::ScheduledMetricsManager(
    PrefService* prefs,
    ShoppingService* shopping_service)
    : pref_service_(prefs), shopping_service_(shopping_service) {
  daily_last_run_ = pref_service_->GetTime(kCommerceDailyMetricsLastUpdateTime);

  base::TimeDelta time_since_last = base::Time::Now() - daily_last_run_;
  int64_t daily_ms_delay = std::clamp(
      (kDailyInterval - time_since_last).InMilliseconds(),
      base::Seconds(0L).InMilliseconds(), kDailyInterval.InMilliseconds());

  daily_scheduled_task_ = std::make_unique<base::CancelableRepeatingClosure>(
      base::BindRepeating(&ScheduledMetricsManager::RunDailyTask,
                          weak_ptr_factory_.GetWeakPtr()));
  base::SequencedTaskRunner::GetCurrentDefault()->PostDelayedTask(
      FROM_HERE, daily_scheduled_task_->callback(),
      base::Milliseconds(daily_ms_delay));
}

ScheduledMetricsManager::~ScheduledMetricsManager() = default;

void ScheduledMetricsManager::RunDailyTask() {
  // Update the last update time in prefs and immediately schedule the next.
  daily_last_run_ = base::Time::Now();
  pref_service_->SetTime(kCommerceDailyMetricsLastUpdateTime, daily_last_run_);
  base::SequencedTaskRunner::GetCurrentDefault()->PostDelayedTask(
      FROM_HERE, daily_scheduled_task_->callback(), kDailyInterval);

  // These metrics should only ever be recorded if the user is eligible for the
  // feature.
  if (commerce::IsShoppingListEligible(
          shopping_service_->GetAccountChecker()) &&
      IsSubscriptionsApiEnabled(shopping_service_->GetAccountChecker())) {
    shopping_service_->GetAllSubscriptions(
        SubscriptionType::kPriceTrack,
        base::BindOnce(
            [](base::WeakPtr<ScheduledMetricsManager> manager,
               std::vector<CommerceSubscription> tracked_products) {
              base::UmaHistogramCounts100(kTrackedProductCountHistogramName,
                                          tracked_products.size());

              PrefService* pref_service =
                  manager ? manager->pref_service_ : nullptr;
              PriceNotificationEmailState state =
                  PriceNotificationEmailState::kNotResponded;
              if (tracked_products.size() > 0) {
                if (pref_service &&
                    pref_service->GetBoolean(kPriceEmailNotificationsEnabled)) {
                  state = PriceNotificationEmailState::kEnabled;
                } else {
                  state = PriceNotificationEmailState::kDisabled;
                }
              }
              base::UmaHistogramEnumeration(
                  kPriceNotificationEmailHistogramName, state);
            },
            weak_ptr_factory_.GetWeakPtr()));
  }
}

}  // namespace commerce::metrics