/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
│                                                                              │
│ Permission to use, copy, modify, and/or distribute this software for         │
│ any purpose with or without fee is hereby granted, provided that the         │
│ above copyright notice and this permission notice appear in all copies.      │
│                                                                              │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
│ PERFORMANCE OF THIS SOFTWARE.                                                │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/limits.h"
#include "libc/log/check.h"
#include "libc/runtime/runtime.h"
#include "libc/stdio/stdio.h"
#include "libc/testlib/ezbench.h"
#include "libc/testlib/testlib.h"
#include "libc/time/time.h"

textstartup static void strftime_test_init(void) {
  setenv("TZ", "GST", true);
}
const void *const strftime_test_ctor[] initarray = {strftime_test_init};

testonly char *FormatTime(const char *fmt, struct tm *tm) {
  static char buf[64];
  strftime(buf, sizeof(buf), fmt, tm);
  return &buf[0];
}

TEST(strftime_100, iso8601_ShakaZuluTime) {
  int64_t t = 0x5cd04d0e;
  ASSERT_STREQ("2019-05-06T15:04:46Z",
               FormatTime("%Y-%m-%dT%H:%M:%SZ", gmtime(&t)));
}

TEST(xiso8601, testUnixYearZero) {
  int64_t t = 0;
  ASSERT_STREQ("1970-01-01T00:00:00Z",
               FormatTime("%Y-%m-%dT%H:%M:%SZ", gmtime(&t)));
}

TEST(strftime_100, rfc2822_ShakaZuluTime) {
  int64_t t = 0x5cd04d0e;
  ASSERT_STREQ("Mon, 06 May 2019 15:04:46 +0000",
               FormatTime("%a, %d %b %Y %T %z", gmtime(&t)));
}

TEST(strftime_100, rfc822_ShakaZuluTime) {
  int64_t t = 0x5cd04d0e;
  ASSERT_STREQ("Mon, 06 May 19 15:04:46 +0000",
               FormatTime("%a, %d %b %y %T %z", gmtime(&t)));
}

TEST(strftime_201, iso8601_GoogleStandardTime) {
  int64_t t = 0x5cd04d0e;
  ASSERT_STREQ("GST", getenv("TZ"));
  ASSERT_STREQ("2019-05-06T08:04:46PDT",
               FormatTime("%Y-%m-%dT%H:%M:%S%Z", localtime(&t)));
}

TEST(strftime_201, rfc2822_GoogleStandardTime) {
  int64_t t = 0x5cd04d0e;
  ASSERT_STREQ("Mon, 06 May 2019 08:04:46 -0700",
               FormatTime("%a, %d %b %Y %T %z", localtime(&t)));
}

TEST(strftime_201, rfc822_GoogleStandardTime) {
  int64_t t = 0x5cd04d0e;
  ASSERT_STREQ("Mon, 06 May 19 08:04:46 -0700",
               FormatTime("%a, %d %b %y %T %z", localtime(&t)));
}

TEST(xiso8601, testAtLeastBetterThanTraditionalUnixLimit) {
  int64_t t = 10737418235;
  ASSERT_STREQ("2310-04-04T16:10:35Z",
               FormatTime("%Y-%m-%dT%H:%M:%SZ", gmtime(&t)));
}

TEST(xiso8601, testSomethingHuge) {
  int64_t t = 7707318812667;
  ASSERT_STREQ("246205-03-18T20:24:27Z",
               FormatTime("%Y-%m-%dT%H:%M:%SZ", gmtime(&t)));
}

// this requires 52 bit year
TEST(xiso8601, testBigBang) {
  struct tm tm;
  int64_t t = -13700000000L * 31536000L;
  CHECK_NOTNULL(gmtime_r(&t, &tm));
  ASSERT_STREQ("-13690902019-07-22T00:00:00Z",
               FormatTime("%Y-%m-%dT%H:%M:%SZ", &tm));
}

// stelliferous era is 10**6 < n < 10**14 years (71-bit)
// we support up to approx. 10**11 yr after the big bang
TEST(xiso8601, testMostOfStelliferousEra) {
  struct tm tm;
  int64_t t = -13700000000L + 100000000000 /*000*/ * 31536000L;
  CHECK_NOTNULL(gmtime_r(&t, &tm));
  ASSERT_STREQ("99933607290-12-11T04:26:40Z",
               FormatTime("%Y-%m-%dT%H:%M:%SZ", &tm));
}

const char *GmtimeFormatTime(void) {
  struct tm tm;
  int64_t t = -13700000000L * 31536000L;
  CHECK_NOTNULL(gmtime_r(&t, &tm));
  return FormatTime("%Y-%m-%dT%H:%M:%SZ", &tm);
}

BENCH(strftime, bench) {
  struct tm tm;
  int64_t t = -13700000000L * 31536000L;
  CHECK_NOTNULL(gmtime_r(&t, &tm));
  EZBENCH2("strftime", donothing, FormatTime("%Y-%m-%dT%H:%M:%SZ", &tm));
  EZBENCH2("gmtime+strftime", donothing, GmtimeFormatTime());
}