From 62d5a5870beee34d8e7a0ba442f6f5c867082aa5 Mon Sep 17 00:00:00 2001
From: tonykcao <98124995+tonykcao@users.noreply.github.com>
Date: Fri, 4 Oct 2024 20:49:34 -0400
Subject: [PATCH] feat: added anytime to date module ##936 (#947)

* feat: added anytime to date module

* broken tests addressed

* broken tests addressed

* removed out of scope changes

* removed out of scope changes

---------

Co-authored-by: Tony Cao <tonykcao@gmail.com>
---
 include/faker-cxx/date.h    | 13 +++++++++++++
 src/modules/date.cpp        | 34 ++++++++++++++++++++++++++++++++++
 tests/modules/date_test.cpp | 36 ++++++++++++++++++++++++++++++++++++
 3 files changed, 83 insertions(+)

diff --git a/include/faker-cxx/date.h b/include/faker-cxx/date.h
index f8eec56bc..8d9a3be7a 100644
--- a/include/faker-cxx/date.h
+++ b/include/faker-cxx/date.h
@@ -13,6 +13,19 @@ enum class DateFormat
     Timestamp,
 };
 
+/**
+ * @brief Generates a random date between UNIX epoch and 200 years from now
+ *
+ * @returns ISO formatted string.
+ *
+ * @code
+ * faker::date::anytime() // "2023-12-08T19:31:32Z"
+ * faker::date::anytime(DateFormat::ISO) // "2020-06-16T15:24:09Z"
+ * faker::date::anytime(DateFormat::Timestamp) // "1592321049"
+ * @endcode
+ */
+FAKER_CXX_EXPORT std::string anytime(DateFormat dateFormat = DateFormat::ISO);
+
 /**
  * @brief Generates a random date in the past.
  *
diff --git a/src/modules/date.cpp b/src/modules/date.cpp
index d2ddcba98..569454899 100644
--- a/src/modules/date.cpp
+++ b/src/modules/date.cpp
@@ -46,6 +46,40 @@ std::string betweenDate(const auto& from, const auto& to, DateFormat dateFormat)
 const auto numberOfHoursInDay = 24;
 const auto numberOfDaysInYear = 365;
 
+std::string anytime(DateFormat dateFormat)
+{
+    constexpr int64_t total_seconds = 3600LL * 24LL* 365LL * 200LL; // sec/hr * hr/d * d/yr * years
+
+    int64_t now_seconds = std::chrono::duration_cast<std::chrono::seconds>(std::chrono::system_clock::now().time_since_epoch()).count();
+    int64_t max_seconds = now_seconds + total_seconds;
+
+    std::random_device rd;
+    std::mt19937_64 gen(rd());
+    std::uniform_int_distribution<int64_t> dis(0, max_seconds);
+
+    int64_t random_seconds = dis(gen);
+
+    auto timePoint = std::chrono::system_clock::time_point{std::chrono::seconds{random_seconds}};
+    std::string result;
+
+    if (dateFormat == DateFormat::Timestamp)
+    {
+        result = std::to_string(random_seconds);
+    }
+    else
+    {
+        time_t timePointTimeT = std::chrono::system_clock::to_time_t(timePoint);
+
+        std::tm utcTime = *std::gmtime(&timePointTimeT);
+
+        std::stringstream ss;
+        ss << std::put_time(&utcTime, "%Y-%m-%dT%H:%M:%SZ");
+        result = ss.str();
+    }
+
+    return result;
+}
+
 std::string futureDate(int years, DateFormat dateFormat)
 {
     const auto startDate = std::chrono::system_clock::now() + std::chrono::hours{1};
diff --git a/tests/modules/date_test.cpp b/tests/modules/date_test.cpp
index 7ae2b4e26..a7b36c241 100644
--- a/tests/modules/date_test.cpp
+++ b/tests/modules/date_test.cpp
@@ -126,6 +126,42 @@ TEST_F(DateTest, shouldGenerateFutureDateTimestamp)
     EXPECT_TRUE(std::chrono::duration_cast<std::chrono::seconds>(futureDate - currentDate).count() < secondsInYear);
     EXPECT_TRUE(futureDate > currentDate);
 }
+TEST_F(DateTest, shouldGenerateAnytimeISO)
+{
+    const auto currentDate = std::chrono::system_clock::now();
+    const auto unixEpoch = std::chrono::system_clock::time_point{};
+
+    for (int i = 0; i < 100; ++i)
+    {
+        const auto anytimeISO = anytime(DateFormat::ISO);
+        const auto generatedDate = parseISOFormattedStringToTimePoint(anytimeISO);
+        EXPECT_GT(generatedDate, unixEpoch);
+
+        auto duration = generatedDate - currentDate;
+        double durationInYears = static_cast<double>(std::chrono::duration_cast<std::chrono::seconds>(duration).count()) / (365.25 * 24 * 3600);
+        durationInYears = std::abs(durationInYears);
+        EXPECT_LT(durationInYears, 201);
+    }
+}
+
+TEST_F(DateTest, shouldGenerateAnytimeTimestamp)
+{
+    const auto currentDate = std::chrono::system_clock::now();
+    const auto unixEpoch = std::chrono::system_clock::time_point{};
+
+    for (int i = 0; i < 100; ++i)
+    {
+        const auto anytimeTimestamp = anytime(DateFormat::Timestamp);
+        int64_t timestampSeconds = std::stoll(anytimeTimestamp);
+        auto generatedDate = std::chrono::system_clock::time_point{std::chrono::seconds{timestampSeconds}};
+        EXPECT_GT(generatedDate, unixEpoch);
+
+        auto duration = generatedDate - currentDate;
+        double durationInYears = static_cast<double>(std::chrono::duration_cast<std::chrono::seconds>(duration).count()) / (365.25 * 24 * 3600);
+        durationInYears = std::abs(durationInYears);
+        EXPECT_LT(durationInYears, 201);
+    }
+}
 
 TEST_F(DateTest, shouldGenerateSoonDateISO)
 {