public override PlaybillItem Merge(PlaybillItem nextItem)
{
if (!CanMerge(nextItem))
{
throw new InvalidOperationException();
}
// Note: 是否在自动垫片上操作？
PlaySource mergedSource = ((PlaySourceSegment)this.PlaySource).Merge(nextItem.PlaySource);
return(CreateInternal(mergedSource));
}
internal PlaySource Merge(PlaySource nextSource)
{
if (!CanMerge(nextSource))
{
throw new InvalidOperationException();
}
PlayRange range = this.MediaSource.Merge(this.PlayRange, ((PlaySourceSegment)nextSource).PlayRange);
range = this.PlaySource.Adjust(range); // 确保范围不超出this.PlaySource.PlayRange
return(Create(this.PlaySource, range));
}
private static AutoPlaybillItem CreateInternal(PlaySource playSource)
{
var segment = playSource as PlaySourceSegment;
if (segment != null)
{
return(new AutoPlaybillItem(segment));
}
else
{
return(new AutoPlaybillItem((NormalPlaySource)playSource));
}
}
// 设为internal来阻止外部派生。
internal PlaybillItem(PlaySource playSource, ScheduleMode scheduleMode)
{
if (playSource == null)
{
throw new ArgumentNullException("playSource");
}
if (!Enum.IsDefined(typeof(ScheduleMode), scheduleMode))
{
throw new System.ComponentModel.InvalidEnumArgumentException("scheduleMode", (int)scheduleMode, typeof(ScheduleMode));
}
this.PlaySource = playSource;
this.ScheduleMode = scheduleMode;
}
internal static void Break(this PlaySource playSource, TimeSpan duration, out PlayRange first, out PlayRange second)
{
if (duration <= TimeSpan.Zero)
{
throw new ArgumentOutOfRangeException("duration",
string.Format("<{0}>无效，必须大于TimeSpan.Zero。", duration));
}
if (duration >= playSource.PlayRange.Duration)
{
throw new ArgumentOutOfRangeException("duration",
string.Format("<{0}>无效，必须小于{1}。", duration, playSource.PlayRange.Duration));
}
PlayRange.Break(playSource.PlayRange, duration, out first, out second);
first = playSource.Adjust(first);
second = playSource.Adjust(second);
}
internal bool CanMerge(PlaySource nextSource)
{
var nextSegment = nextSource as PlaySourceSegment;
if (nextSegment == null)
{
return(false);
}
Debug.Assert(nextSegment != this);
if (nextSegment.PlaySource != nextSegment.PlaySource)
{
return(false);
}
return(this.MediaSource.CanMerge(this.PlayRange, nextSegment.PlayRange));
}
internal static PlaybillItem CreateAutoPadding(TimeSpan duration)
{
PlaySource source = FCSPlayout.NormalPlaySource.CreateAutoPadding(duration);
return(CreateAuto(source));
}
