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Terminal.Gui/Terminal.Gui/Views/TextView.cs
Miguel de Icaza 77f554ef04 Doc updates
2018-06-01 16:10:02 -04:00

1090 lines
27 KiB
C#

//
// TextView.cs: multi-line text editing
//
// Authors:
// Miguel de Icaza (miguel@gnome.org)
//
//
// TODO:
// PageUp/PageDown
// Attributed text on spans
// Replace insertion with Insert method
// String accumulation (Control-k, control-k is not preserving the last new line, see StringToRunes
// Alt-D, Alt-Backspace
// API to set the cursor position
// API to scroll to a particular place
// keybindings to go to top/bottom
// public API to insert, remove ranges
// Add word forward/word backwards commands
// Save buffer API
// Mouse
//
// Desirable:
// Move all the text manipulation into the TextModel
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using NStack;
namespace Terminal.Gui {
class TextModel {
List<List<Rune>> lines;
public bool LoadFile (string file)
{
if (file == null)
throw new ArgumentNullException (nameof (file));
try {
var stream = File.OpenRead (file);
} catch {
return false;
}
LoadStream (File.OpenRead (file));
return true;
}
// Turns the ustring into runes, this does not split the
// contents on a newline if it is present.
internal static List<Rune> ToRunes (ustring str)
{
List<Rune> runes = new List<Rune> ();
foreach (var x in str.ToRunes ()) {
runes.Add (x);
}
return runes;
}
// Splits a string into a List that contains a List<Rune> for each line
public static List<List<Rune>> StringToRunes (ustring content)
{
var lines = new List<List<Rune>> ();
int start = 0, i = 0;
for (; i < content.Length; i++) {
if (content [i] == 10) {
if (i - start > 0)
lines.Add (ToRunes (content [start, i]));
else
lines.Add (ToRunes (ustring.Empty));
start = i + 1;
}
}
if (i - start >= 0)
lines.Add (ToRunes (content [start, null]));
return lines;
}
void Append (List<byte> line)
{
var str = ustring.Make (line.ToArray ());
lines.Add (ToRunes (str));
}
public void LoadStream (Stream input)
{
if (input == null)
throw new ArgumentNullException (nameof (input));
lines = new List<List<Rune>> ();
var buff = new BufferedStream (input);
int v;
var line = new List<byte> ();
while ((v = buff.ReadByte ()) != -1) {
if (v == 10) {
Append (line);
line.Clear ();
continue;
}
line.Add ((byte)v);
}
if (line.Count > 0)
Append (line);
}
public void LoadString (ustring content)
{
lines = StringToRunes (content);
}
public override string ToString ()
{
var sb = new StringBuilder ();
foreach (var line in lines) {
sb.Append (line);
sb.AppendLine ();
}
return sb.ToString ();
}
/// <summary>
/// The number of text lines in the model
/// </summary>
public int Count => lines.Count;
/// <summary>
/// Returns the specified line as a List of Rune
/// </summary>
/// <returns>The line.</returns>
/// <param name="line">Line number to retrieve.</param>
public List<Rune> GetLine (int line) => lines [line];
/// <summary>
/// Adds a line to the model at the specified position.
/// </summary>
/// <param name="pos">Line number where the line will be inserted.</param>
/// <param name="runes">The line of text, as a List of Rune.</param>
public void AddLine (int pos, List<Rune> runes)
{
lines.Insert (pos, runes);
}
/// <summary>
/// Removes the line at the specified position
/// </summary>
/// <param name="pos">Position.</param>
public void RemoveLine (int pos)
{
lines.RemoveAt (pos);
}
}
/// <summary>
/// Multi-line text editing view
/// </summary>
/// <remarks>
/// <para>
/// The text view provides a multi-line text view. Users interact
/// with it with the standard Emacs commands for movement or the arrow
/// keys.
/// </para>
/// <list type="table">
/// <listheader>
/// <term>Shortcut</term>
/// <description>Action performed</description>
/// </listheader>
/// <item>
/// <term>Left cursor, Control-b</term>
/// <description>
/// Moves the editing point left.
/// </description>
/// </item>
/// <item>
/// <term>Right cursor, Control-f</term>
/// <description>
/// Moves the editing point right.
/// </description>
/// </item>
/// <item>
/// <term>Alt-b</term>
/// <description>
/// Moves one word back.
/// </description>
/// </item>
/// <item>
/// <term>Alt-f</term>
/// <description>
/// Moves one word forward.
/// </description>
/// </item>
/// <item>
/// <term>Up cursor, Control-p</term>
/// <description>
/// Moves the editing point one line up.
/// </description>
/// </item>
/// <item>
/// <term>Down cursor, Control-n</term>
/// <description>
/// Moves the editing point one line down
/// </description>
/// </item>
/// <item>
/// <term>Home key, Control-a</term>
/// <description>
/// Moves the cursor to the beginning of the line.
/// </description>
/// </item>
/// <item>
/// <term>End key, Control-e</term>
/// <description>
/// Moves the cursor to the end of the line.
/// </description>
/// </item>
/// <item>
/// <term>Delete, Control-d</term>
/// <description>
/// Deletes the character in front of the cursor.
/// </description>
/// </item>
/// <item>
/// <term>Backspace</term>
/// <description>
/// Deletes the character behind the cursor.
/// </description>
/// </item>
/// <item>
/// <term>Control-k</term>
/// <description>
/// Deletes the text until the end of the line and replaces the kill buffer
/// with the deleted text. You can paste this text in a different place by
/// using Control-y.
/// </description>
/// </item>
/// <item>
/// <term>Control-y</term>
/// <description>
/// Pastes the content of the kill ring into the current position.
/// </description>
/// </item>
/// <item>
/// <term>Alt-d</term>
/// <description>
/// Deletes the word above the cursor and adds it to the kill ring. You
/// can paste the contents of the kill ring with Control-y.
/// </description>
/// </item>
/// <item>
/// <term>Control-q</term>
/// <description>
/// Quotes the next input character, to prevent the normal processing of
/// key handling to take place.
/// </description>
/// </item>
/// </list>
/// </remarks>
public class TextView : View {
TextModel model = new TextModel ();
int topRow;
int leftColumn;
int currentRow;
int currentColumn;
int selectionStartColumn, selectionStartRow;
bool selecting;
//bool used;
#if false
/// <summary>
/// Changed event, raised when the text has clicked.
/// </summary>
/// <remarks>
/// Client code can hook up to this event, it is
/// raised when the text in the entry changes.
/// </remarks>
public event EventHandler Changed;
#endif
/// <summary>
/// Public constructor, creates a view on the specified area, with absolute position and size.
/// </summary>
/// <remarks>
/// </remarks>
public TextView (Rect frame) : base (frame)
{
CanFocus = true;
}
/// <summary>
/// Public constructor, creates a view on the specified area, with dimensions controlled with the X, Y, Width and Height properties.
/// </summary>
public TextView () : base ()
{
CanFocus = true;
}
void ResetPosition ()
{
topRow = leftColumn = currentRow = currentColumn = 0;
}
/// <summary>
/// Sets or gets the text in the entry.
/// </summary>
/// <remarks>
/// </remarks>
public ustring Text {
get {
return model.ToString ();
}
set {
ResetPosition ();
model.LoadString (value);
SetNeedsDisplay ();
}
}
/// <summary>
/// Loads the contents of the file into the TextView.
/// </summary>
/// <returns><c>true</c>, if file was loaded, <c>false</c> otherwise.</returns>
/// <param name="path">Path to the file to load.</param>
public bool LoadFile (string path)
{
if (path == null)
throw new ArgumentNullException (nameof (path));
ResetPosition ();
var res = model.LoadFile (path);
SetNeedsDisplay ();
return res;
}
/// <summary>
/// Loads the contents of the stream into the TextView.
/// </summary>
/// <returns><c>true</c>, if stream was loaded, <c>false</c> otherwise.</returns>
/// <param name="stream">Stream to load the contents from.</param>
public void LoadStream (Stream stream)
{
if (stream == null)
throw new ArgumentNullException (nameof (stream));
ResetPosition ();
model.LoadStream(stream);
SetNeedsDisplay ();
}
/// <summary>
/// The current cursor row.
/// </summary>
public int CurrentRow => currentRow;
/// <summary>
/// Gets the cursor column.
/// </summary>
/// <value>The cursor column.</value>
public int CurrentColumn => currentColumn;
/// <summary>
/// Positions the cursor on the current row and column
/// </summary>
public override void PositionCursor ()
{
if (selecting) {
var minRow = Math.Min (Math.Max (Math.Min (selectionStartRow, currentRow)-topRow, 0), Frame.Height);
var maxRow = Math.Min (Math.Max (Math.Max (selectionStartRow, currentRow) - topRow, 0), Frame.Height);
SetNeedsDisplay (new Rect (0, minRow, Frame.Width, maxRow));
}
Move (CurrentColumn - leftColumn, CurrentRow - topRow);
}
void ClearRegion (int left, int top, int right, int bottom)
{
for (int row = top; row < bottom; row++) {
Move (left, row);
for (int col = left; col < right; col++)
AddRune (col, row, ' ');
}
}
void ColorNormal ()
{
Driver.SetAttribute (ColorScheme.Normal);
}
void ColorSelection ()
{
if (HasFocus)
Driver.SetAttribute (ColorScheme.Focus);
else
Driver.SetAttribute (ColorScheme.Normal);
}
// Returns an encoded region start..end (top 32 bits are the row, low32 the column)
void GetEncodedRegionBounds (out long start, out long end)
{
long selection = ((long)(uint)selectionStartRow << 32) | (uint)selectionStartColumn;
long point = ((long)(uint)currentRow << 32) | (uint)currentColumn;
if (selection > point) {
start = point;
end = selection;
} else {
start = selection;
end = point;
}
}
bool PointInSelection (int col, int row)
{
long start, end;
GetEncodedRegionBounds (out start, out end);
var q = ((long)(uint)row << 32) | (uint)col;
return q >= start && q <= end;
}
//
// Returns a ustring with the text in the selected
// region.
//
ustring GetRegion ()
{
long start, end;
GetEncodedRegionBounds (out start, out end);
int startRow = (int)(start >> 32);
var maxrow = ((int)(end >> 32));
int startCol = (int)(start & 0xffffffff);
var endCol = (int)(end & 0xffffffff);
var line = model.GetLine (startRow);
if (startRow == maxrow)
return StringFromRunes (line.GetRange (startCol, endCol));
ustring res = StringFromRunes (line.GetRange (startCol, line.Count - startCol));
for (int row = startRow+1; row < maxrow; row++) {
res = res + ustring.Make ((Rune)10) + StringFromRunes (model.GetLine (row));
}
line = model.GetLine (maxrow);
res = res + ustring.Make ((Rune)10) + StringFromRunes (line.GetRange (0, endCol));
return res;
}
//
// Clears the contents of the selected region
//
void ClearRegion ()
{
long start, end;
long currentEncoded = ((long)(uint)currentRow << 32) | (uint)currentColumn;
GetEncodedRegionBounds (out start, out end);
int startRow = (int)(start >> 32);
var maxrow = ((int)(end >> 32));
int startCol = (int)(start & 0xffffffff);
var endCol = (int)(end & 0xffffffff);
var line = model.GetLine (startRow);
if (startRow == maxrow) {
line.RemoveRange (startCol, endCol - startCol);
currentColumn = startCol;
SetNeedsDisplay (new Rect (0, startRow - topRow, Frame.Width, startRow - topRow + 1));
return;
}
line.RemoveRange (startCol, line.Count - startCol);
var line2 = model.GetLine (maxrow);
line.AddRange (line2.Skip (endCol));
for (int row = startRow + 1; row <= maxrow; row++) {
model.RemoveLine (startRow+1);
}
if (currentEncoded == end) {
currentRow -= maxrow - (startRow);
}
currentColumn = startCol;
SetNeedsDisplay ();
}
/// <summary>
/// Redraw the text editor region
/// </summary>
/// <param name="region">The region to redraw.</param>
public override void Redraw (Rect region)
{
ColorNormal ();
int bottom = region.Bottom;
int right = region.Right;
for (int row = region.Top; row < bottom; row++) {
int textLine = topRow + row;
if (textLine >= model.Count) {
ColorNormal ();
ClearRegion (region.Left, row, region.Right, row + 1);
continue;
}
var line = model.GetLine (textLine);
int lineRuneCount = line.Count;
if (line.Count < region.Left){
ClearRegion (region.Left, row, region.Right, row + 1);
continue;
}
Move (region.Left, row);
for (int col = region.Left; col < right; col++) {
var lineCol = leftColumn + col;
var rune = lineCol >= lineRuneCount ? ' ' : line [lineCol];
if (selecting && PointInSelection (col, row))
ColorSelection ();
else
ColorNormal ();
AddRune (col, row, rune);
}
}
PositionCursor ();
}
public override bool CanFocus {
get => true;
set { base.CanFocus = value; }
}
void SetClipboard (ustring text)
{
Clipboard.Contents = text;
}
void AppendClipboard (ustring text)
{
Clipboard.Contents = Clipboard.Contents + text;
}
void Insert (Rune rune)
{
var line = GetCurrentLine ();
line.Insert (currentColumn, rune);
var prow = currentRow - topRow;
SetNeedsDisplay (new Rect (0, prow, Frame.Width, prow + 1));
}
ustring StringFromRunes (List<Rune> runes)
{
if (runes == null)
throw new ArgumentNullException (nameof (runes));
int size = 0;
foreach (var rune in runes) {
size += Utf8.RuneLen (rune);
}
var encoded = new byte [size];
int offset = 0;
foreach (var rune in runes) {
offset += Utf8.EncodeRune (rune, encoded, offset);
}
return ustring.Make (encoded);
}
List<Rune> GetCurrentLine () => model.GetLine (currentRow);
void InsertText (ustring text)
{
var lines = TextModel.StringToRunes (text);
if (lines.Count == 0)
return;
var line = GetCurrentLine ();
// Optmize single line
if (lines.Count == 1) {
line.InsertRange (currentColumn, lines [0]);
currentColumn += lines [0].Count;
if (currentColumn - leftColumn > Frame.Width)
leftColumn = currentColumn - Frame.Width + 1;
SetNeedsDisplay (new Rect (0, currentRow - topRow, Frame.Width, currentRow - topRow + 1));
return;
}
// Keep a copy of the rest of the line
var restCount = line.Count - currentColumn;
var rest = line.GetRange (currentColumn, restCount);
line.RemoveRange (currentColumn, restCount);
// First line is inserted at the current location, the rest is appended
line.InsertRange (currentColumn, lines [0]);
for (int i = 1; i < lines.Count; i++)
model.AddLine (currentRow + i, lines [i]);
var last = model.GetLine (currentRow + lines.Count-1);
var lastp = last.Count;
last.InsertRange (last.Count, rest);
// Now adjjust column and row positions
currentRow += lines.Count-1;
currentColumn = lastp;
if (currentRow - topRow > Frame.Height) {
topRow = currentRow - Frame.Height + 1;
if (topRow < 0)
topRow = 0;
}
if (currentColumn < leftColumn)
leftColumn = currentColumn;
if (currentColumn-leftColumn >= Frame.Width)
leftColumn = currentColumn - Frame.Width + 1;
SetNeedsDisplay ();
}
// The column we are tracking, or -1 if we are not tracking any column
int columnTrack = -1;
// Tries to snap the cursor to the tracking column
void TrackColumn ()
{
// Now track the column
var line = GetCurrentLine ();
if (line.Count < columnTrack)
currentColumn = line.Count;
else if (columnTrack != -1)
currentColumn = columnTrack;
else if (currentColumn > line.Count)
currentColumn = line.Count;
Adjust ();
}
void Adjust ()
{
bool need = false;
if (currentColumn < leftColumn) {
currentColumn = leftColumn;
need = true;
}
if (currentColumn - leftColumn > Frame.Width) {
leftColumn = currentColumn - Frame.Width + 1;
need = true;
}
if (currentRow < topRow) {
topRow = currentRow;
need = true;
}
if (currentRow - topRow > Frame.Height) {
topRow = currentRow - Frame.Height + 1;
need = true;
}
if (need)
SetNeedsDisplay ();
else
PositionCursor ();
}
bool lastWasKill;
public override bool ProcessKey (KeyEvent kb)
{
int restCount;
List<Rune> rest;
// Handle some state here - whether the last command was a kill
// operation and the column tracking (up/down)
switch (kb.Key) {
case Key.ControlN:
case Key.CursorDown:
case Key.ControlP:
case Key.CursorUp:
lastWasKill = false;
break;
case Key.ControlK:
break;
default:
lastWasKill = false;
columnTrack = -1;
break;
}
// Dispatch the command.
switch (kb.Key) {
case Key.ControlN:
case Key.CursorDown:
if (currentRow + 1 < model.Count) {
if (columnTrack == -1)
columnTrack = currentColumn;
currentRow++;
if (currentRow >= topRow + Frame.Height) {
topRow++;
SetNeedsDisplay ();
}
TrackColumn ();
PositionCursor ();
}
break;
case Key.ControlP:
case Key.CursorUp:
if (currentRow > 0) {
if (columnTrack == -1)
columnTrack = currentColumn;
currentRow--;
if (currentRow < topRow) {
topRow--;
SetNeedsDisplay ();
}
TrackColumn ();
PositionCursor ();
}
break;
case Key.ControlF:
case Key.CursorRight:
var currentLine = GetCurrentLine ();
if (currentColumn < currentLine.Count) {
currentColumn++;
if (currentColumn >= leftColumn + Frame.Width) {
leftColumn++;
SetNeedsDisplay ();
}
PositionCursor ();
} else {
if (currentRow + 1 < model.Count) {
currentRow++;
currentColumn = 0;
leftColumn = 0;
if (currentRow >= topRow + Frame.Height) {
topRow++;
}
SetNeedsDisplay ();
PositionCursor ();
}
break;
}
break;
case Key.ControlB:
case Key.CursorLeft:
if (currentColumn > 0) {
currentColumn--;
if (currentColumn < leftColumn) {
leftColumn--;
SetNeedsDisplay ();
}
PositionCursor ();
} else {
if (currentRow > 0) {
currentRow--;
if (currentRow < topRow) {
topRow--;
}
currentLine = GetCurrentLine ();
currentColumn = currentLine.Count;
int prev = leftColumn;
leftColumn = currentColumn - Frame.Width + 1;
if (leftColumn < 0)
leftColumn = 0;
if (prev != leftColumn)
SetNeedsDisplay ();
PositionCursor ();
}
}
break;
case Key.Delete:
case Key.Backspace:
if (currentColumn > 0) {
// Delete backwards
currentLine = GetCurrentLine ();
currentLine.RemoveAt (currentColumn - 1);
currentColumn--;
if (currentColumn < leftColumn) {
leftColumn--;
SetNeedsDisplay ();
} else
SetNeedsDisplay (new Rect (0, currentRow - topRow, 1, Frame.Width));
} else {
// Merges the current line with the previous one.
if (currentRow == 0)
return true;
var prowIdx = currentRow - 1;
var prevRow = model.GetLine (prowIdx);
var prevCount = prevRow.Count;
model.GetLine (prowIdx).AddRange (GetCurrentLine ());
model.RemoveLine (currentRow);
currentRow--;
currentColumn = prevCount;
leftColumn = currentColumn - Frame.Width + 1;
if (leftColumn < 0)
leftColumn = 0;
SetNeedsDisplay ();
}
break;
// Home, C-A
case Key.Home:
case Key.ControlA:
currentColumn = 0;
if (currentColumn < leftColumn) {
leftColumn = 0;
SetNeedsDisplay ();
} else
PositionCursor ();
break;
case Key.ControlD: // Delete
currentLine = GetCurrentLine ();
if (currentColumn == currentLine.Count) {
if (currentRow + 1 == model.Count)
break;
var nextLine = model.GetLine (currentRow + 1);
currentLine.AddRange (nextLine);
model.RemoveLine (currentRow + 1);
var sr = currentRow - topRow;
SetNeedsDisplay (new Rect (0, sr, Frame.Width, sr + 1));
} else {
currentLine.RemoveAt (currentColumn);
var r = currentRow - topRow;
SetNeedsDisplay (new Rect (currentColumn - leftColumn, r, Frame.Width, r + 1));
}
break;
case Key.End:
case Key.ControlE: // End
currentLine = GetCurrentLine ();
currentColumn = currentLine.Count;
int pcol = leftColumn;
leftColumn = currentColumn - Frame.Width + 1;
if (leftColumn < 0)
leftColumn = 0;
if (pcol != leftColumn)
SetNeedsDisplay ();
PositionCursor ();
break;
case Key.ControlK: // kill-to-end
currentLine = GetCurrentLine ();
if (currentLine.Count == 0) {
model.RemoveLine (currentRow);
var val = ustring.Make ((Rune)'\n');
if (lastWasKill)
AppendClipboard (val);
else
SetClipboard (val);
} else {
restCount = currentLine.Count - currentColumn;
rest = currentLine.GetRange (currentColumn, restCount);
var val = StringFromRunes (rest);
if (lastWasKill)
AppendClipboard (val);
else
SetClipboard (val);
currentLine.RemoveRange (currentColumn, restCount);
}
SetNeedsDisplay (new Rect (0, currentRow - topRow, Frame.Width, Frame.Height));
lastWasKill = true;
break;
case Key.ControlY: // Control-y, yank
InsertText (Clipboard.Contents);
selecting = false;
break;
case Key.ControlSpace:
selecting = true;
selectionStartColumn = currentColumn;
selectionStartRow = currentRow;
break;
case ((int)'w' + Key.AltMask):
SetClipboard (GetRegion ());
selecting = false;
break;
case Key.ControlW:
SetClipboard (GetRegion ());
ClearRegion ();
selecting = false;
break;
case (Key)((int)'b' + Key.AltMask):
var newPos = WordBackward (currentColumn, currentRow);
if (newPos.HasValue) {
currentColumn = newPos.Value.col;
currentRow = newPos.Value.row;
}
Adjust ();
break;
case (Key)((int)'f' + Key.AltMask):
newPos = WordForward (currentColumn, currentRow);
if (newPos.HasValue) {
currentColumn = newPos.Value.col;
currentRow = newPos.Value.row;
}
Adjust ();
break;
case Key.Enter:
var orow = currentRow;
currentLine = GetCurrentLine ();
restCount = currentLine.Count - currentColumn;
rest = currentLine.GetRange (currentColumn, restCount);
currentLine.RemoveRange (currentColumn, restCount);
model.AddLine (currentRow + 1, rest);
currentRow++;
bool fullNeedsDisplay = false;
if (currentRow >= topRow + Frame.Height) {
topRow++;
fullNeedsDisplay = true;
}
currentColumn = 0;
if (currentColumn < leftColumn) {
fullNeedsDisplay = true;
leftColumn = 0;
}
if (fullNeedsDisplay)
SetNeedsDisplay ();
else
SetNeedsDisplay (new Rect (0, currentRow - topRow, 0, Frame.Height));
break;
default:
// Ignore control characters and other special keys
if (kb.Key < Key.Space || kb.Key > Key.CharMask)
return false;
Insert ((uint)kb.Key);
currentColumn++;
if (currentColumn >= leftColumn + Frame.Width) {
leftColumn++;
SetNeedsDisplay ();
}
PositionCursor ();
return true;
}
return true;
}
IEnumerable<(int col, int row, Rune rune)> ForwardIterator (int col, int row)
{
if (col < 0 || row < 0)
yield break;
if (row >= model.Count)
yield break;
var line = GetCurrentLine ();
if (col >= line.Count)
yield break;
while (row < model.Count) {
for (int c = col; c < line.Count; c++) {
yield return (c, row, line [c]);
}
col = 0;
row++;
line = GetCurrentLine ();
}
}
Rune RuneAt (int col, int row) => model.GetLine (row) [col];
bool MoveNext (ref int col, ref int row, out Rune rune)
{
var line = model.GetLine (row);
if (col + 1 < line.Count) {
col++;
rune = line [col];
return true;
}
while (row + 1 < model.Count){
col = 0;
row++;
line = model.GetLine (row);
if (line.Count > 0) {
rune = line [0];
return true;
}
}
rune = 0;
return false;
}
bool MovePrev (ref int col, ref int row, out Rune rune)
{
var line = model.GetLine (row);
if (col > 0) {
col--;
rune = line [col];
return true;
}
if (row == 0) {
rune = 0;
return false;
}
while (row > 0) {
row--;
line = model.GetLine (row);
col = line.Count - 1;
if (col >= 0) {
rune = line [col];
return true;
}
}
rune = 0;
return false;
}
(int col, int row)? WordForward (int fromCol, int fromRow)
{
var col = fromCol;
var row = fromRow;
var line = GetCurrentLine ();
var rune = RuneAt (col, row);
var srow = row;
if (Rune.IsPunctuation (rune) || Rune.IsWhiteSpace (rune)) {
while (MoveNext (ref col, ref row, out rune)){
if (Rune.IsLetterOrDigit (rune))
break;
}
while (MoveNext (ref col, ref row, out rune)) {
if (!Rune.IsLetterOrDigit (rune))
break;
}
} else {
while (MoveNext (ref col, ref row, out rune)) {
if (!Rune.IsLetterOrDigit (rune))
break;
}
}
if (fromCol != col || fromRow != row)
return (col, row);
return null;
}
(int col, int row)? WordBackward (int fromCol, int fromRow)
{
if (fromRow == 0 && fromCol == 0)
return null;
var col = fromCol;
var row = fromRow;
var line = GetCurrentLine ();
var rune = RuneAt (col, row);
if (Rune.IsPunctuation (rune) || Rune.IsSymbol (rune) || Rune.IsWhiteSpace (rune)) {
while (MovePrev (ref col, ref row, out rune)){
if (Rune.IsLetterOrDigit (rune))
break;
}
while (MovePrev (ref col, ref row, out rune)){
if (!Rune.IsLetterOrDigit (rune))
break;
}
} else {
while (MovePrev (ref col, ref row, out rune)) {
if (!Rune.IsLetterOrDigit (rune))
break;
}
}
if (fromCol != col || fromRow != row)
return (col, row);
return null;
}
public override bool MouseEvent (MouseEvent ev)
{
if (!ev.Flags.HasFlag (MouseFlags.Button1Clicked)) {
return false;
}
if (!HasFocus)
SuperView.SetFocus (this);
if (ev.Y + topRow >= model.Count) {
currentRow = model.Count - topRow;
} else {
currentRow = ev.Y + topRow;
}
var r = GetCurrentLine ();
if (ev.X - leftColumn >= r.Count)
currentColumn = r.Count - leftColumn;
else
currentColumn = ev.X - leftColumn;
PositionCursor ();
return true;
}
}
}