Add struct_time, gmtime, localtime, mktime, strftime to lib/time (#219)

lib/time.py

@@ -14,7 +14,74 @@
 
 """Time access and conversions."""
 
-from __go__.time import Now, Second, Sleep  # pylint: disable=g-multiple-import
+from __go__.time import Now, Second, Sleep, Unix, Date, UTC # pylint: disable=g-multiple-import
+
+
+_strftime_directive_map = {
+    '%': '%',
+    'a': 'Mon',
+    'A': 'Monday',
+    'b': 'Jan',
+    'B': 'January',
+    'c': NotImplemented,
+    'd': '02',
+    'H': '15',
+    'I': '03',
+    'j': NotImplemented,
+    'L': '.000',
+    'm': '01',
+    'M': '04',
+    'p': 'PM',
+    'S': '05',
+    'U': NotImplemented,
+    'W': NotImplemented,
+    'w': NotImplemented,
+    'X': NotImplemented,
+    'x': NotImplemented,
+    'y': '06',
+    'Y': '2006',
+    'Z': 'MST',
+    'z': '-0700',
+}
+
+
+class struct_time(tuple):  #pylint: disable=invalid-name,missing-docstring
+
+  def __init__(self, args):
+    super(struct_time, self).__init__(tuple, args)
+    self.tm_year = self[0]
+    self.tm_mon = self[1]
+    self.tm_mday = self[2]
+    self.tm_hour = self[3]
+    self.tm_min = self[4]
+    self.tm_sec = self[5]
+    self.tm_wday = self[6]
+    self.tm_yday = self[7]
+    self.tm_isdst = self[8]
+
+  def __repr__(self):
+    return ("time.struct_time(tm_year=%s, tm_mon=%s, tm_mday=%s, "
+            "tm_hour=%s, tm_min=%s, tm_sec=%s, tm_wday=%s, "
+            "tm_yday=%s, tm_isdst=%s)") % self
+
+  def __str__(self):
+    return repr(self)
+
+
+def gmtime(seconds=None):
+  t = (Unix(seconds, 0) if seconds else Now()).UTC()
+  return struct_time((t.Year(), t.Month(), t.Day(), t.Hour(), t.Minute(),
+                      t.Second(), (t.Weekday() + 6) % 7, t.YearDay(), 0))
+
+
+def localtime(seconds=None):
+  t = (Unix(seconds, 0) if seconds else Now()).Local()
+  return struct_time((t.Year(), t.Month(), t.Day(), t.Hour(), t.Minute(),
+                      t.Second(), (t.Weekday() + 6) % 7, t.YearDay(), 0))
+
+
+def mktime(t):
+  return float(Date(t[0], t[1], t[2], t[3], t[4], t[5], 0, UTC).Unix())
 
 
 def sleep(secs):
@@ -23,3 +90,31 @@ def sleep(secs):
 
 def time():
   return float(Now().UnixNano()) / Second
+
+
+def strftime(format, tt=None):  # pylint: disable=missing-docstring,redefined-builtin
+  t = (Unix(int(mktime(tt)), 0) if tt else Now()).Local()
+  ret = []
+  prev, n = 0, format.find('%', 0, -1)
+  while n != -1:
+    ret.append(format[prev:n])
+    next_ch = format[n + 1]
+    c = _strftime_directive_map.get(next_ch)
+    if c is NotImplemented:
+      raise NotImplementedError('Code: %' + next_ch + ' not yet supported')
+    if c:
+      ret.append(t.Format(c))
+    else:
+      ret.append(format[n:n+2])
+    n += 2
+    prev, n = n, format.find('%', n, -1)
+  ret.append(format[prev:])
+  return ''.join(ret)
+
+
+# TODO: Calculate real value for daylight saving.
+daylight = 0
+
+# TODO: Use local DST instead of ''.
+tzname = (Now().Zone()[0], '')
+