internal IMathAtom BuildTable(string environment, IMathList firstList, bool isRow, char stopChar)
{
var oldEnv = _currentEnvironment;
_currentEnvironment = new TableEnvironmentProperties(environment);
int currentRow = 0;
int currentColumn = 0;
var rows = new List <List <IMathList> > {
new List <IMathList>()
};
if (firstList != null)
{
rows[currentRow].Add(firstList);
if (isRow)
{
_currentEnvironment.NRows++;
currentRow++;
rows.Add(new List <IMathList>());
}
else
{
currentColumn++;
}
}
while (HasCharacters && !(_currentEnvironment.Ended))
{
var list = BuildInternal(false, stopChar);
if (list == null)
{
return(null);
}
rows[currentRow].Add(list);
currentColumn++;
if (_currentEnvironment.NRows > currentRow)
{
currentRow = _currentEnvironment.NRows;
rows.Add(new List <IMathList>());
currentColumn = 0;
}
}
if (_currentEnvironment.Name != null && !_currentEnvironment.Ended)
{
SetError(@"Missing \end");
return(null);
}
var tableResult = MathAtoms.Table(_currentEnvironment.Name, rows);
if (tableResult.Error is string error)
{
SetError(error);
return(null);
}
_currentEnvironment = oldEnv;
return(tableResult.Value);
}
internal IMathAtom _BoundaryAtomForDelimiterType(string delimiterType)
{
string delim = ReadDelimiter();
if (delim == null)
{
SetError("Missing delimiter for " + delimiterType);
return(null);
}
var boundary = MathAtoms.BoundaryAtom(delim);
if (boundary == null)
{
SetError(@"Invalid delimiter for \" + delimiterType + ": " + delim);
}
return(boundary);
}
public static string DelimiterToString(IMathAtom delimiter)
{
var command = MathAtoms.DelimiterName(delimiter);
if (command == null)
{
return(string.Empty);
}
var singleChars = @"()[]<>|./";
if (singleChars.IndexOf(command, StringComparison.OrdinalIgnoreCase) >= 0 && command.Length == 1)
{
return(command);
}
if (command == "||")
{
return(@"\|");
}
else
{
return(@"\" + command);
}
}
public static string MathListToString(IMathList mathList)
{
var builder = new StringBuilder();
var currentFontStyle = FontStyle.Default;
foreach (var atom in mathList)
{
if (currentFontStyle != atom.FontStyle)
{
if (currentFontStyle != FontStyle.Default)
{
// close the previous font style
builder.Append("}");
}
if (atom.FontStyle != FontStyle.Default)
{
// open a new font style
var fontStyleName = atom.FontStyle.FontName();
builder.Append(@"\" + fontStyleName + "{");
}
}
currentFontStyle = atom.FontStyle;
switch (atom.AtomType)
{
case MathAtomType.Fraction: {
var fraction = (IFraction)atom;
var numerator = MathListToString(fraction.Numerator);
var denominator = MathListToString(fraction.Denominator);
if (fraction.HasRule)
{
builder.Append(@"\frac{" + numerator + "}{" + denominator + "}");
}
else
{
string command = null;
if (fraction.LeftDelimiter == null && fraction.RightDelimiter == null)
{
command = "atop";
}
else if (fraction.LeftDelimiter == "(" && fraction.RightDelimiter == ")")
{
command = "choose";
}
else if (fraction.LeftDelimiter == "{" && fraction.RightDelimiter == "}")
{
command = "brace";
}
else if (fraction.LeftDelimiter == "[" && fraction.RightDelimiter == "]")
{
command = "brack";
}
else
{
command = $"atopwithdelims{fraction.LeftDelimiter}{fraction.RightDelimiter}";
}
builder.Append("{" + numerator + @" \" + command + " " + denominator + "}");
}
}
break;
case MathAtomType.Radical: {
builder.Append(@"\sqrt");
var radical = (IRadical)atom;
if (radical.Degree != null)
{
builder.Append($"[{MathListToString(radical.Degree)}]");
}
builder.Append("{" + MathListToString(radical.Radicand) + "}");
break;
}
case MathAtomType.Inner: {
var inner = (IMathInner)atom;
if (inner.LeftBoundary == null && inner.RightBoundary == null)
{
builder.Append("{" + MathListToString(inner.InnerList) + "}");
}
else
{
if (inner.LeftBoundary == null)
{
builder.Append(@"\left. ");
}
else
{
builder.Append(@"\left" + DelimiterToString(inner.LeftBoundary) + " ");
}
builder.Append(MathListToString(inner.InnerList));
if (inner.RightBoundary == null)
{
builder.Append(@"\right. ");
}
else
{
builder.Append(@"\right" + DelimiterToString(inner.RightBoundary) + " ");
}
}
break;
}
case MathAtomType.Table: {
var table = (IMathTable)atom;
if (table.Environment != null)
{
builder.Append(@"\begin{" + table.Environment + "}");
}
for (int i = 0; i < table.NRows; i++)
{
var row = table.Cells[i];
for (int j = 0; j < row.Count; j++)
{
var cell = row[j];
if (table.Environment == "matrix")
{
if (cell.Count >= 1 && cell[0].AtomType == MathAtomType.Style)
{
// remove the first atom.
var atoms = cell.Atoms.GetRange(1, cell.Count - 1);
cell = MathLists.WithAtoms(atoms.ToArray());
}
}
if (table.Environment == "eqalign" || table.Environment == "aligned" || table.Environment == "split")
{
if (j == 1 && cell.Count >= 1 && cell[0].AtomType == MathAtomType.Ordinary && string.IsNullOrEmpty(cell[0].Nucleus))
{
// empty nucleus added for spacing. Remove it.
var atoms = cell.Atoms.GetRange(1, cell.Count - 1);
cell = MathLists.WithAtoms(atoms.ToArray());
}
}
builder.Append(MathListToString(cell));
if (j < row.Count - 1)
{
builder.Append("&");
}
}
if (i < table.NRows - 1)
{
builder.Append(@"\\ ");
}
}
if (table.Environment != null)
{
builder.Append(@"\end{" + table.Environment + "}");
}
break;
}
case MathAtomType.Overline: {
var over = (IOverline)atom;
builder.Append(@"\overline{" + MathListToString(over.InnerList) + "}");
break;
}
case MathAtomType.Underline: {
var under = (IUnderline)atom;
builder.Append(@"\underline{" + MathListToString(under.InnerList) + "}");
break;
}
case MathAtomType.Accent: {
var accent = (IAccent)atom;
var list = accent.InnerList;
accent.InnerList = null; //for lookup
builder.Append(@"\" + MathAtoms.Commands[(MathAtom)atom] + "{" + MathListToString(list) + "}");
break;
}
case MathAtomType.LargeOperator: {
var op = (LargeOperator)atom;
var command = MathAtoms.LatexSymbolNameForAtom(op);
var originalOperator = (LargeOperator)MathAtoms.ForLatexSymbolName(command);
builder.Append($@"\{command} ");
if (originalOperator.Limits != op.Limits)
{
switch (op.Limits)
{
case true:
builder.Append(@"\limits ");
break;
case false:
if (!op.NoLimits)
{
builder.Append(@"\nolimits ");
}
break;
case null:
break;
}
}
break;
}
case MathAtomType.Space: {
var space = (ISpace)atom;
var intSpace = (int)space.Length;
if (SpaceToCommands.ContainsKey(intSpace) && intSpace == space.Length)
{
var command = SpaceToCommands[intSpace];
builder.Append(@"\" + command + " ");
}
else
{
if (space.IsMu)
{
builder.Append(@"\mkern" + space.Length.ToString("0.0") + "mu");
}
else
{
builder.Append(@"\kern" + space.Length.ToString("0.0") + "pt");
}
}
break;
}
case MathAtomType.Style: {
var style = (IStyle)atom;
var command = StyleToCommands[style.LineStyle];
builder.Append(@"\" + command + " ");
break;
}
case MathAtomType.Color: {
var color = (IColor)atom;
builder.Append($@"\color{{{color.ColorString}}}{{{MathListToString(color.InnerList)}}}");
break;
}
case MathAtomType.Group:
builder.AppendInBraces(MathListToString(((Group)atom).InnerList), NullHandling.EmptyContent);
break;
case MathAtomType.Prime:
builder.Append('\'', ((Prime)atom).Length);
break;
default: {
var aNucleus = atom.Nucleus;
if (String.IsNullOrEmpty(aNucleus))
{
builder.Append(@"{}");
}
else if (aNucleus == "\u2236")
{
builder.Append(":");
}
else if (aNucleus == "\u2212")
{
builder.Append("-");
}
else
{
var command = MathAtoms.LatexSymbolNameForAtom((MathAtom)atom);
if (command == null)
{
if (atom is Extension.I_ExtensionAtom ext)
{
builder.Append(Extension._MathListDestructor.MathAtomToString(ext));
}
else
{
builder.Append(aNucleus);
}
}
else
{
builder.Append(@"\" + command + " ");
}
}
break;
}
}
if (atom.Subscript != null)
{
var scriptString = MathListToString(atom.Subscript);
builder.Append(scriptString.Length == 1 ? $"_{scriptString}" : $"_{{{scriptString}}}");
}
if (atom.Superscript != null)
{
var scriptString = MathListToString(atom.Superscript);
builder.Append(scriptString.Length == 1 ? $"^{scriptString}" : $"^{{{scriptString}}}");
}
}
if (currentFontStyle != FontStyle.Default)
{
builder.Append("}");
}
return(builder.ToString());
}
internal IMathList BuildInternal(bool oneCharOnly, char stopChar)
{
if (oneCharOnly && stopChar > 0)
{
throw new InvalidOperationException("Cannot set both oneCharOnly and stopChar");
}
var r = new MathList();
IMathAtom prevAtom = null;
while (HasCharacters)
{
if (_error != null)
{
return(null);
}
IMathAtom atom;
var ch = GetNextCharacter();
if (oneCharOnly)
{
if (ch == '^' || ch == '}' || ch == '_' || ch == '&')
{
// this is not the character we are looking for. They are for the caller to look at.
UnlookCharacter();
return(r);
}
}
if (stopChar > 0 && ch == stopChar)
{
return(r);
}
switch (ch)
{
case '^':
if (prevAtom == null || prevAtom.Superscript != null || !prevAtom.ScriptsAllowed)
{
prevAtom = MathAtoms.Create(MathAtomType.Ordinary, string.Empty);
r.Add(prevAtom);
}
// this is a superscript for the previous atom.
// note, if the next char is StopChar, it will be consumed and doesn't count as stop.
prevAtom.Superscript = this.BuildInternal(true);
continue;
case '_':
if (prevAtom == null || prevAtom.Subscript != null || !prevAtom.ScriptsAllowed)
{
prevAtom = MathAtoms.Create(MathAtomType.Ordinary, string.Empty);
r.Add(prevAtom);
}
// this is a subscript for the previous atom.
// note, if the next char is StopChar, it will be consumed and doesn't count as stop.
prevAtom.Subscript = this.BuildInternal(true);
continue;
case '{':
IMathList sublist;
if (_currentEnvironment != null && _currentEnvironment.Name == null)
{
// \\ or \cr which do not have a corrosponding \end
var oldEnv = _currentEnvironment;
_currentEnvironment = null;
sublist = BuildInternal(false, '}');
_currentEnvironment = oldEnv;
}
else
{
sublist = BuildInternal(false, '}');
}
if (sublist == null)
{
return(null);
}
prevAtom = sublist.Atoms.LastOrDefault();
if (oneCharOnly)
{
r.Append(sublist);
return(r);
}
#warning TODO Example
//https://phabricator.wikimedia.org/T99369
//https://phab.wmfusercontent.org/file/data/xsimlcnvo42siudvwuzk/PHID-FILE-bdcqexocj5b57tj2oezn/math_rendering.png
//dt, \text{d}t, \partial t, \nabla\psi \\ \underline\overline{dy/dx, \text{d}y/\text{d}x, \frac{dy}{dx}, \frac{\text{d}y}{\text{d}x}, \frac{\partial^2}{\partial x_1\partial x_2}y} \\ \prime,
atom = new Group {
InnerList = sublist
};
break;
case '}':
if (oneCharOnly || stopChar != 0)
{
throw new InvalidCodePathException("This should have been handled before.");
}
SetError("Missing opening brace");
return(null);
case '\\':
var command = ReadCommand();
var done = StopCommand(command, r, stopChar);
if (done != null)
{
return(done);
}
if (_error != null)
{
return(null);
}
if (ApplyModifier(command, prevAtom))
{
continue;
}
var fontStyleQ = MathAtoms.FontStyle(command);
if (fontStyleQ.HasValue)
{
var fontStyle = fontStyleQ.Value;
var oldSpacesAllowed = _textMode;
var oldFontStyle = _currentFontStyle;
_textMode = (command == "text");
_currentFontStyle = fontStyle;
var childList = BuildInternal(true);
if (childList == null)
{
return(null);
}
_currentFontStyle = oldFontStyle;
_textMode = oldSpacesAllowed;
prevAtom = childList.Atoms.LastOrDefault();
r.Append(childList);
if (oneCharOnly)
{
return(r);
}
continue;
}
atom = AtomForCommand(command, stopChar);
if (atom == null)
{
SetError(_error ?? "Internal error");
return(null);
}
break;
case '&': { // column separation in tables
if (_currentEnvironment != null)
{
return(r);
}
var table = BuildTable(null, r, false, stopChar);
if (table == null)
{
return(null);
}
return(MathLists.WithAtoms(table));
}
case '\'': // this case is NOT in iosMath
int i = 1;
while (ExpectCharacter('\''))
{
i++;
}
atom = new Prime(i);
break;
default:
if (_textMode && ch == ' ')
{
atom = MathAtoms.ForLatexSymbolName(" ");
}
else
{
atom = MathAtoms.ForCharacter(ch);
if (atom == null)
{
// not a recognized character
continue;
}
}
break;
}
if (atom == null)
{
throw new InvalidCodePathException("Atom shouldn't be null");
}
atom.FontStyle = _currentFontStyle;
r.Add(atom);
prevAtom = atom;
if (oneCharOnly)
{
return(r); // we consumed our character.
}
}
if (stopChar > 0)
{
if (stopChar == '}')
{
SetError("Missing closing brace");
}
else
{
// we never found our stop character.
SetError("Expected character not found: " + stopChar.ToString());
}
}
return(r);
}
internal IMathAtom AtomForCommand(string command, char stopChar)
{
var atom = MathAtoms.ForLatexSymbolName(command);
if (atom is Accent accent)
{
accent.InnerList = BuildInternal(true);
return(accent);
}
if (atom != null)
{
return(atom);
}
switch (command)
{
case "frac":
return(new Fraction {
Numerator = BuildInternal(true),
Denominator = BuildInternal(true)
});
case "binom":
return(new Fraction(false)
{
Numerator = BuildInternal(true),
Denominator = BuildInternal(true),
LeftDelimiter = "(",
RightDelimiter = ")"
});
case "sqrt":
var rad = new Radical();
if (ExpectCharacter('['))
{
rad.Degree = BuildInternal(false, ']');
rad.Radicand = BuildInternal(true);
}
else
{
rad.Radicand = BuildInternal(true);
}
return(rad);
case "left":
var oldInner = _currentInnerAtom;
_currentInnerAtom = new Inner {
LeftBoundary = _BoundaryAtomForDelimiterType("left")
};
if (_currentInnerAtom.LeftBoundary == null)
{
return(null);
}
_currentInnerAtom.InnerList = BuildInternal(false, stopChar);
if (_currentInnerAtom.RightBoundary == null)
{
SetError("Missing \\right");
return(null);
}
var newInner = _currentInnerAtom;
_currentInnerAtom = oldInner;
return(newInner);
case "overline":
return(new Overline {
InnerList = BuildInternal(true)
});
case "underline":
return(new Underline()
{
InnerList = BuildInternal(true)
});
case "begin":
var env = ReadEnvironment();
if (env == null)
{
return(null);
}
var table = BuildTable(env, null, false, stopChar);
return(table);
case "color":
return(new Color {
ColorString = ReadColor(),
InnerList = BuildInternal(true)
});
case "prime":
SetError(@"\prime won't be supported as Unicode has no matching character. Use ' instead.");
return(null);
default:
var extResult = Extension._MathListBuilder.AtomForCommand(this, command);
if (extResult != null)
{
return(extResult);
}
SetError("Invalid command \\" + command);
return(null);
}
}
