// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/der/encode_values.h"

#include "base/time/time.h"
#include "net/der/parse_values.h"

namespace net {

namespace der {

namespace {

bool WriteFourDigit(uint16_t value, uint8_t out[4]) {
  if (value >= 10000)
    return false;
  out[3] = '0' + (value % 10);
  value /= 10;
  out[2] = '0' + (value % 10);
  value /= 10;
  out[1] = '0' + (value % 10);
  value /= 10;
  out[0] = '0' + value;
  return true;
}

bool WriteTwoDigit(uint8_t value, uint8_t out[2]) {
  if (value >= 100)
    return false;
  out[0] = '0' + (value / 10);
  out[1] = '0' + (value % 10);
  return true;
}

}  // namespace

bool EncodeTimeAsGeneralizedTime(const base::Time& time,
                                 GeneralizedTime* generalized_time) {
  base::Time::Exploded exploded;
  time.UTCExplode(&exploded);
  if (!exploded.HasValidValues())
    return false;

  generalized_time->year = exploded.year;
  generalized_time->month = exploded.month;
  generalized_time->day = exploded.day_of_month;
  generalized_time->hours = exploded.hour;
  generalized_time->minutes = exploded.minute;
  generalized_time->seconds = exploded.second;
  return true;
}

bool EncodeGeneralizedTime(const GeneralizedTime& time,
                           uint8_t out[kGeneralizedTimeLength]) {
  if (!WriteFourDigit(time.year, out) || !WriteTwoDigit(time.month, out + 4) ||
      !WriteTwoDigit(time.day, out + 6) ||
      !WriteTwoDigit(time.hours, out + 8) ||
      !WriteTwoDigit(time.minutes, out + 10) ||
      !WriteTwoDigit(time.seconds, out + 12)) {
    return false;
  }
  out[14] = 'Z';
  return true;
}

bool EncodeUTCTime(const GeneralizedTime& time, uint8_t out[kUTCTimeLength]) {
  if (!time.InUTCTimeRange())
    return false;

  uint16_t year = time.year - 1900;
  if (year >= 100)
    year -= 100;

  if (!WriteTwoDigit(year, out) || !WriteTwoDigit(time.month, out + 2) ||
      !WriteTwoDigit(time.day, out + 4) ||
      !WriteTwoDigit(time.hours, out + 6) ||
      !WriteTwoDigit(time.minutes, out + 8) ||
      !WriteTwoDigit(time.seconds, out + 10)) {
    return false;
  }
  out[12] = 'Z';
  return true;
}

}  // namespace der

}  // namespace net