File size: 5,167 Bytes
fab29d7 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 | using System;
using System.Globalization;
namespace VersOne.Epub.Internal
{
internal static class SmilClockParser
{
public const Int64 MAX_TIMECOUNT = (Int64)Int32.MaxValue * MILLISECONDS_IN_HOUR;
private const int MILLISECONDS_IN_SECOND = 1000;
private const int MILLISECONDS_IN_MINUTE = 60 * MILLISECONDS_IN_SECOND;
private const int MILLISECONDS_IN_HOUR = 60 * MILLISECONDS_IN_MINUTE;
public static bool TryParse(string smilClock, out EpubNarrationTimestamp result)
{
if (string.IsNullOrWhiteSpace(smilClock))
{
result = default;
return false;
}
smilClock = smilClock.Trim();
if (smilClock.Contains(":"))
{
return TryParseClockValue(smilClock, out result);
}
else
{
return TryParseTimecountValue(smilClock, out result);
}
}
private static bool TryParseClockValue(string clockValue, out EpubNarrationTimestamp result)
{
string[] parts = clockValue.Split(':');
if (parts.Length > 3)
{
result = default;
return false;
}
int hour;
int currentPartIndex;
if (parts.Length == 3)
{
if (!Int32.TryParse(parts[0], out hour) || hour < 0)
{
result = default;
return false;
}
currentPartIndex = 1;
}
else
{
hour = 0;
currentPartIndex = 0;
}
if (!Int32.TryParse(parts[currentPartIndex], out int minute) || minute < 0 || minute >= 60)
{
result = default;
return false;
}
currentPartIndex++;
if (!Decimal.TryParse(parts[currentPartIndex], NumberStyles.AllowDecimalPoint, CultureInfo.InvariantCulture, out decimal secondWithFraction) ||
secondWithFraction < 0 || secondWithFraction >= 60)
{
result = default;
return false;
}
int second = (int)Math.Truncate(secondWithFraction);
int millisecond = (int)Math.Truncate((secondWithFraction - second) * 1000);
result = new EpubNarrationTimestamp(hour, minute, second, millisecond);
return true;
}
private static bool TryParseTimecountValue(string timecountValue, out EpubNarrationTimestamp result)
{
bool hasMetric = false;
int metricStartIndex = -1;
for (int i = 0; i < timecountValue.Length; i++)
{
char c = timecountValue[i];
if (!Char.IsDigit(c) && c != '.')
{
hasMetric = true;
metricStartIndex = i;
break;
}
}
string timecountWithFractionString = hasMetric ? timecountValue.Substring(0, metricStartIndex) : timecountValue;
if (!Decimal.TryParse(timecountWithFractionString, NumberStyles.AllowDecimalPoint, CultureInfo.InvariantCulture, out decimal timecountWithFraction) ||
timecountWithFraction > MAX_TIMECOUNT)
{
result = default;
return false;
}
int metricMultiplier;
if (hasMetric)
{
string metric = timecountValue.Substring(metricStartIndex);
switch (metric)
{
case "h":
metricMultiplier = MILLISECONDS_IN_HOUR;
break;
case "min":
metricMultiplier = MILLISECONDS_IN_MINUTE;
break;
case "s":
metricMultiplier = MILLISECONDS_IN_SECOND;
break;
case "ms":
metricMultiplier = 1;
break;
default:
result = default;
return false;
}
}
else
{
metricMultiplier = MILLISECONDS_IN_SECOND;
}
decimal milliseconds = Math.Truncate(timecountWithFraction * metricMultiplier);
result = ConvertMillisecondsToEpubNarrationTimestamp(milliseconds);
return true;
}
private static EpubNarrationTimestamp ConvertMillisecondsToEpubNarrationTimestamp(decimal milliseconds)
{
int millisecond = (int)(milliseconds % MILLISECONDS_IN_SECOND);
int second = (int)(Math.Truncate(milliseconds / MILLISECONDS_IN_SECOND) % 60);
int minute = (int)(Math.Truncate(milliseconds / MILLISECONDS_IN_MINUTE) % 60);
int hour = (int)Math.Truncate(milliseconds / MILLISECONDS_IN_HOUR);
return new(hour, minute, second, millisecond);
}
}
}
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