webvtt_timestamp.cc

// Copyright 2017 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd

#include "packager/media/formats/webvtt/webvtt_timestamp.h"

#include <ctype.h>

#include "packager/base/logging.h"
#include "packager/base/strings/string_number_conversions.h"

namespace shaka {
namespace media {
namespace {

bool GetTotalMilliseconds(uint64_t hours,
                          uint64_t minutes,
                          uint64_t seconds,
                          uint64_t ms,
                          uint64_t* out) {
  DCHECK(out);
  if (minutes > 59 || seconds > 59 || ms > 999) {
    VLOG(1) << "Hours:" << hours
            << " Minutes:" << minutes
            << " Seconds:" << seconds
            << " MS:" << ms
            << " shoud have never made it to GetTotalMilliseconds";
    return false;
  }
  *out = 60 * 60 * 1000 * hours +
         60 * 1000 * minutes +
         1000 * seconds +
         ms;
  return true;
}
}  // namespace

bool WebVttTimestampParse(const base::StringPiece& source, uint64_t* out) {
  DCHECK(out);

  if (source.length() < 9) {
    LOG(WARNING) << "Timestamp '" << source << "' is mal-formed";
    return false;
  }

  const size_t minutes_begin = source.length() - 9;
  const size_t seconds_begin = source.length() - 6;
  const size_t milliseconds_begin = source.length() - 3;

  uint64_t hours = 0;
  uint64_t minutes = 0;
  uint64_t seconds = 0;
  uint64_t ms = 0;

  const bool has_hours = minutes_begin >= 3 &&
      source[minutes_begin-1] == ':' &&
      base::StringToUint64(source.substr(0, minutes_begin-1), &hours);

  if ((minutes_begin == 0 || has_hours) &&
      source[seconds_begin-1] == ':' &&
      source[milliseconds_begin-1] == '.' &&
      base::StringToUint64(source.substr(minutes_begin, 2), &minutes) &&
      base::StringToUint64(source.substr(seconds_begin, 2), &seconds) &&
      base::StringToUint64(source.substr(milliseconds_begin, 3), &ms)) {
    return GetTotalMilliseconds(hours, minutes, seconds, ms, out);
  }

  LOG(WARNING) << "Timestamp '" << source << "' is mal-formed";
  return false;
}
}  // namespace media
}  // namespace shaka