private static ProjectData SetTaskPredecessorsOrSuccessors(ProjectData project, TaskId id, string value, bool isSuccessors)
{
var linkField = isSuccessors ? TaskFields.SuccessorLinks : TaskFields.PredecessorLinks;
value = value.Trim();
var predecessorsBuilder = ImmutableArray.CreateBuilder <TaskId>();
var remainingTaskLinks = project.Get(linkField, id).ToList();
if (value.Length > 0)
{
var parts = value.Split(',');
foreach (var part in parts)
{
var partText = part.Trim();
var taskText = partText;
var sign = Math.Max(partText.IndexOf('+'), partText.IndexOf('-'));
var lag = TimeSpan.Zero;
if (sign >= 0)
{
var lagText = partText.Substring(sign).Trim();
lag = project.Information.TimeConversion.ParseDuration(lagText);
taskText = partText.Substring(0, sign).Trim();
}
var taskOrdinalText = taskText;
var linkType = (TaskLinkType?)null;
if (taskText.EndsWith("FS", StringComparison.OrdinalIgnoreCase))
{
linkType = TaskLinkType.FinishToStart;
}
else if (taskText.EndsWith("SS", StringComparison.OrdinalIgnoreCase))
{
linkType = TaskLinkType.StartToStart;
}
else if (taskText.EndsWith("FF", StringComparison.OrdinalIgnoreCase))
{
linkType = TaskLinkType.FinishToFinish;
}
else if (taskText.EndsWith("SF", StringComparison.OrdinalIgnoreCase))
{
linkType = TaskLinkType.StartToFinish;
}
if (linkType != null)
{
taskOrdinalText = taskText.Substring(0, taskText.Length - 2).Trim();
}
else if (sign < 0)
{
linkType = TaskLinkType.FinishToStart;
}
else
{
throw new FormatException($"'{partText}' isn't a valid value");
}
if (!int.TryParse(taskOrdinalText, out var taskOrdinal))
{
throw new FormatException($"'{taskOrdinalText}' isn't a valid int");
}
var taskId = project.GetTask(taskOrdinal);
if (taskId.IsDefault)
{
throw new FormatException($"'{taskOrdinal}' isn't a valid task");
}
var predecessorId = isSuccessors ? id : taskId;
var successorId = isSuccessors ? taskId : id;
var taskLink = TaskLink.Create(predecessorId, successorId, linkType.Value, lag);
var existingLink = project.GetTaskLink(predecessorId, successorId);
if (existingLink != null)
{
project = project.RemoveTaskLink(existingLink);
}
else if (project.TaskLinkCausesCycle(taskLink))
{
var predecessorOrdinal = project.Get(TaskFields.Ordinal, predecessorId);
var successorOrdinal = project.Get(TaskFields.Ordinal, successorId);
throw new InvalidOperationException($"Cannot add a link from task {predecessorOrdinal} to task {successorOrdinal} as this would cause a cycle.");
}
project = project.AddTaskLink(taskLink);
remainingTaskLinks.Remove(taskLink);
}
}
foreach (var taskLink in remainingTaskLinks)
{
project = project.RemoveTaskLink(taskLink);
}
return(project);
}