2 files changed, 71 insertions, 16 deletions

diff --git a/include/datetime/date-time.h b/include/datetime/date-time.h
index 4be35f7..6e73ff3 100644
--- a/include/datetime/date-time.h
+++ b/include/datetime/date-time.h
@@ -38,13 +38,15 @@ public:
     static DateTime NowLocal();
     static DateTime Local(int years, int months, int days, int hours, int minutes, int seconds);
 
+    DateTime();
     explicit DateTime(time_t t);
-    explicit DateTime(GDateTime* in=nullptr);
-    DateTime& operator=(GDateTime* in);
+    DateTime(GTimeZone* tz, GDateTime* dt);
     DateTime& operator=(const DateTime& in);
     DateTime to_timezone(const std::string& zone) const;
+    DateTime start_of_day() const;
+    DateTime start_of_minute() const;
+    DateTime add_days(int days) const;
     DateTime add_full(int years, int months, int days, int hours, int minutes, double seconds) const;
-    void reset(GDateTime* in=nullptr);
 
     GDateTime* get() const;
     GDateTime* operator()() const {return get();}
@@ -69,6 +71,8 @@ public:
     bool is_set() const { return m_dt != nullptr; }
 
 private:
+    void reset(GTimeZone*, GDateTime*);
+    std::shared_ptr<GTimeZone> m_tz;
     std::shared_ptr<GDateTime> m_dt;
 };
 
diff --git a/src/date-time.cpp b/src/date-time.cpp
index a139ea9..33b1590 100644
--- a/src/date-time.cpp
+++ b/src/date-time.cpp
@@ -27,42 +27,49 @@ namespace datetime {
 ****
 ***/
 
-DateTime::DateTime(GDateTime* gdt)
+DateTime::DateTime()
 {
-    reset(gdt);
 }
 
-DateTime& DateTime::operator=(GDateTime* gdt)
+DateTime::DateTime(GTimeZone* gtz, GDateTime* gdt)
 {
-    reset(gdt);
-    return *this;
+    g_return_if_fail((gtz==nullptr) == (gdt==nullptr));
+
+    reset(gtz, gdt);
 }
 
 DateTime& DateTime::operator=(const DateTime& that)
 {
+    m_tz = that.m_tz;
     m_dt = that.m_dt;
     return *this;
 }
 
 DateTime::DateTime(time_t t)
 {
+    auto gtz = g_time_zone_new_local();
     auto gdt = g_date_time_new_from_unix_local(t);
-    reset(gdt);
+    reset(gtz, gdt);
+    g_time_zone_unref(gtz);
     g_date_time_unref(gdt);
 }
 
 DateTime DateTime::NowLocal()
 {
+    auto gtz = g_time_zone_new_local();
     auto gdt = g_date_time_new_now_local();
-    DateTime dt(gdt);
+    DateTime dt(gtz, gdt);
+    g_time_zone_unref(gtz);
     g_date_time_unref(gdt);
     return dt;
 }
 
 DateTime DateTime::Local(int year, int month, int day, int hour, int minute, int seconds)
 {
+    auto gtz = g_time_zone_new_local();
     auto gdt = g_date_time_new_local (year, month, day, hour, minute, seconds);
-    DateTime dt(gdt);
+    DateTime dt(gtz, gdt);
+    g_time_zone_unref(gtz);
     g_date_time_unref(gdt);
     return dt;
 }
@@ -71,20 +78,51 @@ DateTime DateTime::to_timezone(const std::string& zone) const
 {
     auto gtz = g_time_zone_new(zone.c_str());
     auto gdt = g_date_time_to_timezone(get(), gtz);
-    DateTime dt(gdt);
+    DateTime dt(gtz, gdt);
     g_time_zone_unref(gtz);
     g_date_time_unref(gdt);
     return dt;
 }
 
+DateTime DateTime::start_of_day() const
+{
+    g_assert(is_set());
+    g_assert(m_tz.get() != nullptr);
+
+    int y=0, m=0, d=0;
+    ymd(y, m, d);
+    auto gdt = g_date_time_new(m_tz.get(), y, m, d, 0, 0, 0);
+    DateTime dt(m_tz.get(), gdt);
+    g_date_time_unref(gdt);
+    return dt;
+}
+
+DateTime DateTime::start_of_minute() const
+{
+    g_assert(is_set());
+    g_assert(m_tz.get() != nullptr);
+
+    int y=0, m=0, d=0;
+    ymd(y, m, d);
+    auto gdt = g_date_time_new(m_tz.get(), y, m, d, hour(), minute(), 0);
+    DateTime dt(m_tz.get(), gdt);
+    g_date_time_unref(gdt);
+    return dt;
+}
+
 DateTime DateTime::add_full(int years, int months, int days, int hours, int minutes, double seconds) const
 {
     auto gdt = g_date_time_add_full(get(), years, months, days, hours, minutes, seconds);
-    DateTime dt(gdt);
+    DateTime dt(m_tz.get(), gdt);
     g_date_time_unref(gdt);
     return dt;
 }
 
+DateTime DateTime::add_days(int days) const
+{
+    return add_full(0, 0, days, 0, 0, 0);
+}
+
 GDateTime* DateTime::get() const
 {
     g_assert(m_dt);
@@ -135,12 +173,25 @@ int64_t DateTime::to_unix() const
     return g_date_time_to_unix(get());
 }
 
-void DateTime::reset(GDateTime* in)
+void DateTime::reset(GTimeZone* gtz, GDateTime* gdt)
 {
-    if (in)
+    g_return_if_fail ((gdt==nullptr) == (gtz==nullptr)); // all or nothin'
+
+    if (gtz)
+    {
+        auto deleter = [](GTimeZone* tz){g_time_zone_unref(tz);};
+        m_tz = std::shared_ptr<GTimeZone>(g_time_zone_ref(gtz), deleter);
+        g_assert(m_tz);
+    }
+    else
+    {
+        m_tz.reset();
+    }
+    
+    if (gdt)
     {
         auto deleter = [](GDateTime* dt){g_date_time_unref(dt);};
-        m_dt = std::shared_ptr<GDateTime>(g_date_time_ref(in), deleter);
+        m_dt = std::shared_ptr<GDateTime>(g_date_time_ref(gdt), deleter);
         g_assert(m_dt);
     }
     else