From e9c27cd8646aeddd6d000a0e1d56bd5c2e7b3ece Mon Sep 17 00:00:00 2001
From: Dmitry Kokorin <dmitry@kokorin.org>
Date: Fri, 18 Mar 2016 14:30:57 +0300
Subject: [PATCH] clock: passes tests, iteration 1 (?)

---
 cpp/clock/clock.cpp | 71 +++++++++++++++++++++++++++++++++++++++++++++
 cpp/clock/clock.h   | 35 ++++++++++++++++++++++
 2 files changed, 106 insertions(+)
 create mode 100644 cpp/clock/clock.cpp
 create mode 100644 cpp/clock/clock.h

diff --git a/cpp/clock/clock.cpp b/cpp/clock/clock.cpp
new file mode 100644
index 0000000..8f34e4e
--- /dev/null
+++ b/cpp/clock/clock.cpp
@@ -0,0 +1,71 @@
+#include "clock.h"
+
+#include <cstring>
+
+namespace date_independent {
+
+namespace {
+
+const minutes_t minutes_per_hour = 60;
+const hours_t   hours_per_day    = 24;
+const total_t   minutes_per_day  = hours_per_day * minutes_per_hour;
+
+inline void make_date_independent(total_t total_minutes)
+{
+    while (total_minutes < 0)
+        total_minutes += minutes_per_day;
+
+    total_minutes = total_minutes % minutes_per_day;
+}
+
+}
+
+
+clock::clock(hours_t hours, minutes_t minutes)
+{
+    total_minutes_ = minutes_per_hour*hours + minutes;
+    make_date_independent(total_minutes_);
+}
+
+bool clock::operator==(const clock &other) const
+{
+    return total_minutes_ == other.total_minutes_;
+}
+
+bool clock::operator!=(const clock &other) const
+{
+    return !(*this == other);
+}
+
+clock clock::at(hours_t hours, minutes_t minutes)
+{
+    return clock(hours, minutes);
+}
+
+clock clock::plus(minutes_t minutes) const
+{
+    clock result(*this);
+
+    result.total_minutes_ += minutes;
+    make_date_independent(result.total_minutes_);
+
+    return result;
+}
+
+clock clock::minus(minutes_t minutes) const
+{
+    return plus(-minutes);
+}
+
+clock::operator std::string() const
+{
+    minutes_t minutes = total_minutes_ % minutes_per_hour
+    hours_t   hours   = total_minutes_ / minutes_per_hour;
+
+    char buff[6];
+    snprintf(buff, 6, "%.2i:%.2i", hours, minutes);
+
+    return buff;
+}
+
+}
diff --git a/cpp/clock/clock.h b/cpp/clock/clock.h
new file mode 100644
index 0000000..3d2253d
--- /dev/null
+++ b/cpp/clock/clock.h
@@ -0,0 +1,35 @@
+#pragma once
+
+#define EXERCISM_RUN_ALL_TESTS
+
+#include <string>
+
+namespace date_independent {
+
+typedef long  total_t;
+typedef short hours_t;
+typedef short minutes_t;
+
+
+class clock
+{
+    total_t total_minutes_;
+
+public:
+
+    clock(hours_t hours = 0, minutes_t minutes = 0);
+    clock(const clock&) = default;
+    clock &operator=(const clock&) = default;
+
+    bool operator==(const clock&) const;
+    bool operator!=(const clock&) const;
+
+    static clock at(hours_t hours, minutes_t minutes = 0);
+
+    clock plus(minutes_t minutes) const;
+    clock minus(minutes_t minutes) const;
+
+    operator std::string() const;
+};
+
+}