/// <summary>
/// Creates a ReadOnlyRegionHandle for the given buffer and span.
/// </summary>
/// <param name="version">
/// The <see cref="TextVersion"/> with which this read only region is associated.
/// </param>
/// <param name="span">
/// The span of interest.
/// </param>
/// <param name="trackingMode">
/// Specifies the tracking behavior of the read only region.
/// </param>
/// <param name="edgeInsertionMode">
/// Specifies if insertions should be allowed at the edges
/// </param>
/// <remarks>
/// Don't call this constructor with invalid parameters. It doesn't verify all of them.
/// </remarks>
internal ReadOnlyRegion(TextVersion version, Span span, SpanTrackingMode trackingMode, EdgeInsertionMode edgeInsertionMode, DynamicReadOnlyRegionQuery callback)
{
_edgeInsertionMode = edgeInsertionMode;
// TODO: change to simple forward tracking text span
_trackingSpan = new ForwardFidelityTrackingSpan(version, span, trackingMode);
QueryCallback = callback;
}
internal TextContentChangedEventArgs ApplyReload(StringRebuilder newContent, EditOptions editOptions, object editTag)
{
// we construct a normalized change list where the inserted text is a reference string that
// points "forward" to the next snapshot and whose deleted text is a reference string that points
// "backward" to the prior snapshot. This pins both snapshots in memory but that's better than materializing
// giant strings, and when (?) we have paging text storage, memory requirements will be minimal.
TextVersion newVersion = new TextVersion(this, this.currentVersion.VersionNumber + 1, this.currentVersion.VersionNumber + 1, newContent.Length);
ITextSnapshot oldSnapshot = this.currentSnapshot;
TextSnapshot newSnapshot = new TextSnapshot(this, newVersion, newContent);
ReferenceChangeString oldText = new ReferenceChangeString(new SnapshotSpan(oldSnapshot, 0, oldSnapshot.Length));
ReferenceChangeString newText = new ReferenceChangeString(new SnapshotSpan(newSnapshot, 0, newSnapshot.Length));
TextChange change = new TextChange(oldPosition: 0,
oldText: oldText,
newText: newText,
currentSnapshot: oldSnapshot);
this.currentVersion.AddNextVersion(NormalizedTextChangeCollection.Create(new FrugalList <TextChange>()
{
change
},
editOptions.ComputeMinimalChange
? (StringDifferenceOptions?)editOptions.DifferenceOptions
: null,
this.textDifferencingService,
oldSnapshot, newSnapshot),
newVersion);
this.builder = newContent;
this.currentVersion = newVersion;
this.currentSnapshot = newSnapshot;
return(new TextContentChangedEventArgs(oldSnapshot, newSnapshot, editOptions, editTag));
}
internal TextContentChangedEventArgs ApplyReload(StringRebuilder newContent, EditOptions editOptions, object editTag)
{
// we construct a normalized change list where the inserted text is a reference string that
// points "forward" to the next snapshot and whose deleted text is a reference string that points
// "backward" to the prior snapshot. This pins both snapshots in memory but that's better than materializing
// giant strings, and when (?) we have paging text storage, memory requirements will be minimal.
ITextSnapshot oldSnapshot = this.currentSnapshot;
StringRebuilder oldContent = BufferFactoryService.StringRebuilderFromSnapshotSpan(new SnapshotSpan(oldSnapshot, 0, oldSnapshot.Length));
TextChange change = TextChange.Create(oldPosition: 0,
oldText: oldContent,
newText: newContent,
currentSnapshot: oldSnapshot);
TextVersion newVersion = this.currentVersion.CreateNext(changes: null, newLength: newContent.Length, reiteratedVersionNumber: -1);
TextSnapshot newSnapshot = new TextSnapshot(this, newVersion, newContent);
this.currentVersion.SetChanges(NormalizedTextChangeCollection.Create(new TextChange[] { change },
editOptions.ComputeMinimalChange
? (StringDifferenceOptions?)editOptions.DifferenceOptions
: null,
this.textDifferencingService,
oldSnapshot, newSnapshot));
this.currentVersion = newVersion;
this.builder = newContent;
this.currentSnapshot = newSnapshot;
return(new TextContentChangedEventArgs(oldSnapshot, newSnapshot, editOptions, editTag));
}
public ForwardFidelityCustomTrackingSpan(TextVersion version, Span span, object customState, CustomTrackToVersion behavior)
: base(version, span, SpanTrackingMode.Custom)
{
if (behavior == null)
{
throw new ArgumentNullException(nameof(behavior));
}
this.behavior = behavior;
this.customState = customState;
}
protected BaseBuffer(IContentType contentType, int initialLength, ITextDifferencingService textDifferencingService, GuardedOperations guardedOperations)
{
// parameters are validated outside
Debug.Assert(contentType != null);
this.contentType = contentType;
this.currentVersion = new TextVersion(this, 0, 0, initialLength);
this.textDifferencingService = textDifferencingService;
this.guardedOperations = guardedOperations;
}
protected BaseBuffer(IContentType contentType, int initialLength, ITextDifferencingService textDifferencingService, GuardedOperations guardedOperations)
{
// parameters are validated outside
Debug.Assert(contentType != null);
this.contentType = contentType;
this.currentVersion = new TextVersion(this, new TextImageVersion(initialLength));
// this.builder should be set in calling ctor
this.textDifferencingService = textDifferencingService;
this.guardedOperations = guardedOperations;
}
/// <summary>
/// Attaches the change to the current node and creates the next version node
/// </summary>
public TextVersion CreateNext(INormalizedTextChangeCollection changes, int reiteratedVersionNumber)
{
this.normalizedChanges = changes;
int delta = 0;
int changeCount = changes.Count;
for (int c = 0; c < changeCount; ++c)
{
delta += changes[c].Delta;
}
this.next = new TextVersion(this.TextBuffer, this.VersionNumber + 1, reiteratedVersionNumber, this.versionLength + delta);
return(this.next);
}
/// <summary>
/// Create a new version based on applying <paramref name="changes"/> to this.
/// </summary>
/// <param name="changes">null if set later</param>
/// <param name="newLength">use -1 to compute a length</param>
/// <param name="reiteratedVersionNumber">use -1 to get the default value</param>
/// <remarks>
/// <para>If <paramref name="changes"/> can be null, then <paramref name="newLength"/> cannot be -1.</para>
/// </remarks>
internal TextVersion CreateNext(INormalizedTextChangeCollection changes, int newLength = -1, int reiteratedVersionNumber = -1)
{
if (this.Next != null)
{
throw new InvalidOperationException("Not allowed to CreateNext twice");
}
var newTextImageVersion = this._textImageVersion.CreateNext(reiteratedVersionNumber: reiteratedVersionNumber, length: newLength, changes: changes);
var next = new TextVersion(this.TextBuffer, newTextImageVersion);
this.Next = next;
return(next);
}
/// <summary>
/// Used when the normalized change list of a version needs to refer ahead to the following snapshot
/// </summary>
public void AddNextVersion(INormalizedTextChangeCollection changes, TextVersion nextVersion)
{
this.normalizedChanges = changes;
this.next = nextVersion;
}
protected void SetCurrentVersionAndSnapshot(INormalizedTextChangeCollection normalizedChanges, int reiteratedVersionNumber = -1)
{
this.currentVersion = this.currentVersion.CreateNext(normalizedChanges, newLength: -1, reiteratedVersionNumber: reiteratedVersionNumber);
this.builder = this.ApplyChangesToStringRebuilder(normalizedChanges, this.builder);
this.currentSnapshot = TakeSnapshot();
}
protected void SetCurrentVersionAndSnapshot(INormalizedTextChangeCollection normalizedChanges)
{
this.currentVersion = this.currentVersion.CreateNext(normalizedChanges);
UpdateSnapshot();
}
protected void SetCurrentVersionAndSnapshot(INormalizedTextChangeCollection normalizedChanges, int reiteratedVersionNumber)
{
this.currentVersion = this.currentVersion.CreateNext(normalizedChanges, reiteratedVersionNumber);
UpdateSnapshot();
}
/// <summary>
/// Construct a ReadOnlySpanCollection that contains everything in a list of spans.
/// </summary>
/// <param name="regions">ReadOnlyRegions</param>
/// <param name="version">The version this span collection applies to.</param>
/// <remarks>
/// <para>The list of spans will be sorted and normalized (overlapping and adjoining spans will be combined).</para>
/// </remarks>
/// <exception cref="ArgumentNullException"><paramref name="regions"/> is null.</exception>
internal ReadOnlySpanCollection(TextVersion version, IEnumerable <IReadOnlyRegion> regions)
: base(NormalizeSpans(version, regions))
{
regionsWithActions = regions.Where(region => region.QueryCallback != null).ToList();
}
private static IList <ReadOnlySpan> NormalizeSpans(TextVersion version, IEnumerable <IReadOnlyRegion> regions)
{
List <IReadOnlyRegion> sorted = new List <IReadOnlyRegion>(regions.Where(region => region.QueryCallback == null));
if (sorted.Count == 0)
{
return(new FrugalList <ReadOnlySpan>());
}
else if (sorted.Count == 1)
{
return(new FrugalList <ReadOnlySpan>()
{
new ReadOnlySpan(version, sorted[0])
});
}
else
{
sorted.Sort((s1, s2) => s1.Span.GetSpan(version).Start.CompareTo(s2.Span.GetSpan(version).Start));
List <ReadOnlySpan> normalized = new List <ReadOnlySpan>(sorted.Count);
int oldStart = sorted[0].Span.GetSpan(version).Start;
int oldEnd = sorted[0].Span.GetSpan(version).End;
EdgeInsertionMode oldStartEdgeInsertionMode = sorted[0].EdgeInsertionMode;
EdgeInsertionMode oldEndEdgeInsertionMode = sorted[0].EdgeInsertionMode;
SpanTrackingMode oldSpanTrackingMode = sorted[0].Span.TrackingMode;
for (int i = 1; (i < sorted.Count); ++i)
{
int newStart = sorted[i].Span.GetSpan(version).Start;
int newEnd = sorted[i].Span.GetSpan(version).End;
// Since the new span's start occurs after the old span's end, we can just add the old span directly.
if (oldEnd < newStart)
{
normalized.Add(new ReadOnlySpan(version, new Span(oldStart, oldEnd - oldStart), oldSpanTrackingMode, oldStartEdgeInsertionMode, oldEndEdgeInsertionMode));
oldStart = newStart;
oldEnd = newEnd;
oldStartEdgeInsertionMode = sorted[i].EdgeInsertionMode;
oldEndEdgeInsertionMode = sorted[i].EdgeInsertionMode;
oldSpanTrackingMode = sorted[i].Span.TrackingMode;
}
else
{
// The two read only regions start at the same position
if (newStart == oldStart)
{
// If one read only region denies edge insertions, combined they do as well
if (sorted[i].EdgeInsertionMode == EdgeInsertionMode.Deny)
{
oldStartEdgeInsertionMode = EdgeInsertionMode.Deny;
}
// This is tricky. We want one span that will be inclusive tracking, and one that won't.
if (oldSpanTrackingMode != sorted[i].Span.TrackingMode)
{
// Since the read only regions cover the same exact span, the combined one will be edge inclusive tracking
if (oldEnd == newEnd)
{
oldSpanTrackingMode = SpanTrackingMode.EdgeInclusive;
}
else if (oldEnd < newEnd)
{
// Since the old span and new span don't have the same span tracking mode and don't end in the same position, we need to create a new span that is edge inclusive
// and deny inserts between it and the next span.
normalized.Add(new ReadOnlySpan(version, new Span(oldStart, oldEnd - oldStart), SpanTrackingMode.EdgeInclusive, oldStartEdgeInsertionMode, EdgeInsertionMode.Deny));
oldStart = oldEnd; // Explicitly use the old end here since we want these spans to be adjacent
oldEnd = newEnd;
oldStartEdgeInsertionMode = sorted[i].EdgeInsertionMode;
oldEndEdgeInsertionMode = sorted[i].EdgeInsertionMode;
oldSpanTrackingMode = sorted[i].Span.TrackingMode;
}
else
{
// Since the new span ends first, create a span that is edge inclusive tracking that ends at the the new span's end.
normalized.Add(new ReadOnlySpan(version, new Span(newStart, newEnd - newStart), SpanTrackingMode.EdgeInclusive, oldStartEdgeInsertionMode, EdgeInsertionMode.Deny));
oldStart = newEnd; // Explicitly use the new end here since we want these spans to be adjacent
}
}
}
if (oldEnd < newEnd)
{
// If the tracking modes are different then we need to create a new span
// with the old tracking mode, and start a new span with the new span tracking mode.
// Also, if the old end and the new start are identical and both edge insertion mode's
// are allow, then we need to create a new span.
if (((oldEnd == newStart)
&&
((oldEndEdgeInsertionMode == EdgeInsertionMode.Allow) && (sorted[i].EdgeInsertionMode == EdgeInsertionMode.Allow)))
||
(oldSpanTrackingMode != sorted[i].Span.TrackingMode))
{
normalized.Add(new ReadOnlySpan(version, new Span(oldStart, oldEnd - oldStart), oldSpanTrackingMode, oldStartEdgeInsertionMode, oldEndEdgeInsertionMode));
oldStart = oldEnd; // Explicitly use the old end here since we want these spans to be adjacent.
oldEnd = newEnd;
// If we are splitting up the spans because of a change in tracking mode, then explicitly deny inserting between them
if (oldSpanTrackingMode != sorted[i].Span.TrackingMode)
{
oldStartEdgeInsertionMode = EdgeInsertionMode.Deny; // Explicitly use deny here since we don't want to allow insertions between these spans
}
else
{
oldStartEdgeInsertionMode = EdgeInsertionMode.Allow;
}
oldEndEdgeInsertionMode = sorted[i].EdgeInsertionMode;
oldSpanTrackingMode = sorted[i].Span.TrackingMode;
}
else
{
oldEnd = newEnd;
oldEndEdgeInsertionMode = sorted[i].EdgeInsertionMode;
}
}
else if (oldEnd == newEnd)
{
if (sorted[i].EdgeInsertionMode == EdgeInsertionMode.Deny)
{
oldEndEdgeInsertionMode = EdgeInsertionMode.Deny;
}
if (oldSpanTrackingMode != sorted[i].Span.TrackingMode)
{
normalized.Add(new ReadOnlySpan(version, new Span(oldStart, oldEnd - oldStart), oldSpanTrackingMode, oldStartEdgeInsertionMode, oldEndEdgeInsertionMode));
oldStart = newEnd;
oldEnd = newEnd;
oldStartEdgeInsertionMode = sorted[i].EdgeInsertionMode;
oldEndEdgeInsertionMode = sorted[i].EdgeInsertionMode;
oldSpanTrackingMode = sorted[i].Span.TrackingMode;
}
}
}
}
normalized.Add(new ReadOnlySpan(version, new Span(oldStart, oldEnd - oldStart), oldSpanTrackingMode, oldStartEdgeInsertionMode, oldEndEdgeInsertionMode));
return(normalized);
}
}
