From e7671b92f11e50232e6fcdd4c2b17c2d94165c5a Mon Sep 17 00:00:00 2001
From: Christopher Lam <christopher.lck@gmail.com>
Date: Thu, 12 Sep 2024 19:49:21 +0800
Subject: [PATCH] fixup!

---
 libgnucash/engine/gnc-datetime.cpp | 117 +++++++++++++++++------------
 1 file changed, 68 insertions(+), 49 deletions(-)

diff --git a/libgnucash/engine/gnc-datetime.cpp b/libgnucash/engine/gnc-datetime.cpp
index a0f09ac8270..9a82d63fef2 100644
--- a/libgnucash/engine/gnc-datetime.cpp
+++ b/libgnucash/engine/gnc-datetime.cpp
@@ -82,54 +82,7 @@ static constexpr auto ticks_per_second = INT64_C(1000000);
 static constexpr auto ticks_per_second = INT64_C(1000000000);
 #endif
 
-
-static icu::Locale
-get_LCTIME_locale()
-{
-    const char* lc_time_locale = setlocale(LC_TIME, nullptr);
-
-    if (lc_time_locale == nullptr)
-        return icu::Locale::getDefault();
-
-    std::string localeStr(lc_time_locale);
-    size_t dotPos = localeStr.find('.');
-    if (dotPos != std::string::npos)
-        localeStr = localeStr.substr(0, dotPos);
-
-    return icu::Locale::createCanonical (localeStr.c_str());
-}
-
-static Date
-icu_string_to_date (const std::string str)
-{
-    UErrorCode status = U_ZERO_ERROR;
-    icu::Locale locale = get_LCTIME_locale();
-
-    static std::unique_ptr<icu::DateFormat> formatter(icu::DateFormat::createDateInstance(icu::DateFormat::kDefault, locale));
-    if (formatter == nullptr)
-        throw std::invalid_argument ("Cannot create date formatter.");
-
-    static std::unique_ptr<icu::Calendar> calendar(icu::Calendar::createInstance(locale, status));
-    if (U_FAILURE(status))
-        throw std::invalid_argument("Cannot create calendar instance.");
-    calendar->setLenient (false);
-
-    icu::UnicodeString input = icu::UnicodeString::fromUTF8(str);
-    icu::ParsePosition parsePos;
-
-    UDate date = formatter->parse(input, parsePos);
-    if (parsePos.getErrorIndex() != -1 || parsePos.getIndex() != input.length())
-        throw std::invalid_argument ("Cannot parse string");
-
-    calendar->setTime(date, status);
-    if (U_FAILURE(status))
-        throw std::invalid_argument ("Cannot set calendar time");
-
-    return Date (calendar->get(UCAL_YEAR, status),
-                 calendar->get(UCAL_MONTH, status) + 1,
-                 calendar->get(UCAL_DATE, status));
-}
-
+boost::gregorian::date static gregorian_date_from_locale_string (const std::string& str);
 
 
 /* Vector of date formats understood by gnucash and corresponding
@@ -142,7 +95,7 @@ const std::vector<GncDateFormat> GncDate::c_formats ({
     GncDateFormat { N_("UK date"), boost::gregorian::from_uk_string },
     GncDateFormat { N_("US date"), boost::gregorian::from_us_string },
     GncDateFormat { N_("ISO date"), boost::gregorian::from_string },
-    GncDateFormat { N_("Locale"), icu_string_to_date },
+    GncDateFormat { N_("Locale"), gregorian_date_from_locale_string },
     GncDateFormat {
         N_("y-m-d"),
         "(?:"                                   // either y-m-d
@@ -666,6 +619,72 @@ GncDateTimeImpl::timestamp()
     return str.substr(0, 8) + str.substr(9, 15);
 }
 
+
+
+
+struct ICUResources
+{
+    std::unique_ptr<icu::DateFormat> formatter;
+    std::unique_ptr<icu::Calendar> calendar;
+};
+
+static ICUResources&
+get_icu_resources()
+{
+    static ICUResources rv;
+
+    if (!rv.formatter)
+    {
+        icu::Locale locale;
+
+        const char* lc_time_locale = setlocale(LC_TIME, nullptr);
+        if (lc_time_locale != nullptr)
+        {
+            std::string localeStr(lc_time_locale);
+            size_t dotPos = localeStr.find('.');
+            if (dotPos != std::string::npos)
+                localeStr = localeStr.substr(0, dotPos);
+
+            locale = icu::Locale::createCanonical (localeStr.c_str());
+        }
+
+        rv.formatter.reset(icu::DateFormat::createDateInstance(icu::DateFormat::kDefault, locale));
+        if (!rv.formatter)
+            throw std::invalid_argument("Cannot create date formatter.");
+
+        UErrorCode status = U_ZERO_ERROR;
+        rv.calendar.reset(icu::Calendar::createInstance(locale, status));
+        if (U_FAILURE(status))
+            throw std::invalid_argument("Cannot create calendar instance.");
+
+        rv.calendar->setLenient(false);
+    }
+
+    return rv;
+}
+
+boost::gregorian::date
+static gregorian_date_from_locale_string (const std::string& str)
+{
+    ICUResources& resources = get_icu_resources();
+
+    icu::UnicodeString input = icu::UnicodeString::fromUTF8(str);
+    icu::ParsePosition parsePos;
+
+    UDate date = resources.formatter->parse(input, parsePos);
+    if (parsePos.getErrorIndex() != -1 || parsePos.getIndex() != input.length())
+        throw std::invalid_argument ("Cannot parse string");
+
+    UErrorCode status = U_ZERO_ERROR;
+    resources.calendar->setTime(date, status);
+    if (U_FAILURE(status))
+        throw std::invalid_argument ("Cannot set calendar time");
+
+    return boost::gregorian::date (resources.calendar->get(UCAL_YEAR, status),
+                                   resources.calendar->get(UCAL_MONTH, status) + 1,
+                                   resources.calendar->get(UCAL_DATE, status));
+}
+
 /* Member function definitions for GncDateImpl.
  */
 GncDateImpl::GncDateImpl(const std::string str, const std::string fmt) :