public static Result <TextAtom> Build(ReadOnlySpan <char> latexSource)
{
if (latexSource.IsEmpty)
{
return(new TextAtom.List(Array.Empty <TextAtom>(), 0));
}
bool? displayMath = null;
StringBuilder mathLaTeX = null;
bool backslashEscape = false;
bool afterCommand = false; //ignore spaces after command
bool afterNewline = false;
int dollarCount = 0;
var globalAtoms = new TextAtomListBuilder();
var breakList = new List <BreakAtInfo>();
breaker.BreakWords(latexSource, breakList);
Result CheckDollarCount(TextAtomListBuilder atoms)
{
switch (dollarCount)
{
case 0:
break;
case 1:
dollarCount = 0;
switch (displayMath)
{
case true:
return("Cannot close display math mode with $");
case false:
if (atoms.Add(mathLaTeX.ToString(), false).Error is string mathError)
{
return("[Math mode error] " + mathError);
}
mathLaTeX = null;
displayMath = null;
break;
case null:
mathLaTeX = new StringBuilder();
displayMath = false;
break;
}
break;
case 2:
dollarCount = 0;
switch (displayMath)
{
case true:
if (atoms.Add(mathLaTeX.ToString(), true).Error is string mathError)
{
return("[Math mode error] " + mathError);
}
mathLaTeX = null;
displayMath = null;
break;
case false:
return("Cannot close inline math mode with $$");
case null:
mathLaTeX = new StringBuilder();
displayMath = true;
break;
}
break;
default:
return("Invalid number of $: " + dollarCount);
}
return(Ok());
}
Result <int> BuildBreakList(ReadOnlySpan <char> latex, TextAtomListBuilder atoms, int i, bool oneCharOnly, char stopChar)
{
void ParagraphBreak()
{
atoms.Break(3);
#warning Should the newline and space occupy the same range?
atoms.TextLength -= 3;
atoms.Add(Space.ParagraphIndent, 3);
}
for (; i < breakList.Count; i++)
{
void ObtainRange(ReadOnlySpan <char> latexInput, int index, out int start, out int end, out ReadOnlySpan <char> section, out WordKind kind)
{
(start, end) = (index == 0 ? 0 : breakList[index - 1].breakAt, breakList[index].breakAt);
section = latexInput.Slice(start, end - start);
kind = breakList[index].wordKind;
}
ObtainRange(latex, i, out var startAt, out var endAt, out var textSection, out var wordKind);
bool SetPrevRange(ReadOnlySpan <char> latexInput, ref ReadOnlySpan <char> section)
{
bool success = i-- > 0;
if (success)
{
ObtainRange(latexInput, i, out startAt, out endAt, out section, out wordKind);
}
return(success);
}
bool SetNextRange(ReadOnlySpan <char> latexInput, ref ReadOnlySpan <char> section)
{
bool success = ++i < breakList.Count;
if (success)
{
ObtainRange(latexInput, i, out startAt, out endAt, out section, out wordKind);
}
return(success);
}
Result <TextAtom> ReadArgumentAtom(ReadOnlySpan <char> latexInput)
{
backslashEscape = false;
var argAtoms = new TextAtomListBuilder();
if (BuildBreakList(latexInput, argAtoms, ++i, true, '\0').Bind(index => i = index).Error is string error)
{
return(error);
}
return(argAtoms.Build());
}
SpanResult <char> ReadArgumentString(ReadOnlySpan <char> latexInput, ref ReadOnlySpan <char> section)
{
afterCommand = false;
if (!SetNextRange(latexInput, ref section))
{
return(Err("Missing argument"));
}
if (section.IsNot('{'))
{
return(Err("Missing {"));
}
int endingIndex = -1;
//startAt + 1 to not start at the { we started at
bool isEscape = false;
for (int j = startAt + 1, bracketDepth = 0; j < latexInput.Length; j++)
{
if (latexInput[j] == '\\')
{
isEscape = true;
}
else if (latexInput[j] == '{' && !isEscape)
{
bracketDepth++;
}
else if (latexInput[j] == '}' && !isEscape)
{
if (bracketDepth > 0)
{
bracketDepth--;
}
else
{
endingIndex = j; break;
}
}
else
{
isEscape = false;
}
}
if (endingIndex == -1)
{
return(Err("Missing }"));
}
var resultText = latexInput.Slice(endAt, endingIndex - endAt);
while (startAt < endingIndex)
{
_ = SetNextRange(latexInput, ref section); //this never fails because the above check
}
return(Ok(resultText));
}
ReadOnlySpan <char> LookAheadForPunc(ReadOnlySpan <char> latexInput, ref ReadOnlySpan <char> section)
{
int start = endAt;
while (SetNextRange(latexInput, ref section))
{
if (wordKind != WordKind.Punc || SpecialChars.Contains(section[0]))
{
//We have overlooked by one
SetPrevRange(latexInput, ref section);
break;
}
}
return(latexInput.Slice(start, endAt - start));
}
//Nothing should be before dollar sign checking -- dollar sign checking uses continue;
atoms.TextLength = startAt;
if (textSection.Is('$'))
{
if (backslashEscape)
{
if (displayMath != null)
{
mathLaTeX.Append(@"\$");
}
else
{
atoms.Add("$", LookAheadForPunc(latex, ref textSection));
}
}
else
{
dollarCount++;
continue;
}
backslashEscape = false;
}
else
{
{ if (CheckDollarCount(atoms).Error is string error)
{
return(error);
}
}
if (!backslashEscape)
{
//Unescaped text section, inside display/inline math mode
if (displayMath != null)
{
switch (textSection)
{
case var _ when textSection.Is('$'):
throw new InvalidCodePathException("The $ case should have been accounted for.");
case var _ when textSection.Is('\\'):
backslashEscape = true;
continue;
default:
mathLaTeX.Append(textSection);
break;
}
}
//Unescaped text section, not inside display/inline math mode
else
{
switch (textSection)
{
case var _ when stopChar > 0 && textSection[0] == stopChar:
return(Ok(i));
case var _ when textSection.Is('$'):
throw new InvalidCodePathException("The $ case should have been accounted for.");
case var _ when textSection.Is('\\'):
backslashEscape = true;
continue;
case var _ when textSection.Is('#'):
return("Unexpected command argument reference character # outside of new command definition (currently unsupported)");
case var _ when textSection.Is('^'):
case var _ when textSection.Is('_'):
return($"Unexpected script indicator {textSection[0]} outside of math mode");
case var _ when textSection.Is('&'):
return($"Unexpected alignment tab character & outside of table environments");
case var _ when textSection.Is('~'):
atoms.Add();
break;
case var _ when textSection.Is('%'):
var comment = new StringBuilder();
while (SetNextRange(latex, ref textSection) && wordKind != WordKind.NewLine)
{
comment.Append(textSection);
}
atoms.Comment(comment.ToString());
break;
case var _ when textSection.Is('{'):
if (BuildBreakList(latex, atoms, ++i, false, '}').Bind(index => i = index).Error is string error)
{
return(error);
}
break;
case var _ when textSection.Is('}'):
return("Unexpected }, unbalanced braces");
case var _ when wordKind == WordKind.NewLine:
//Consume newlines after commands
//Double newline == paragraph break
if (afterNewline)
{
ParagraphBreak();
afterNewline = false;
break;
}
else
{
atoms.Add();
afterNewline = true;
continue;
}
case var _ when wordKind == WordKind.Whitespace:
//Collpase spaces
if (afterCommand)
{
continue;
}
else
{
atoms.Add();
}
break;
default: //Just ordinary text
if (oneCharOnly)
{
if (startAt + 1 < endAt) //Only re-read if current break span is more than 1 long
{
i--;
breakList[i] = new BreakAtInfo(breakList[i].breakAt + 1, breakList[i].wordKind);
}
//Need to allocate in the end :(
//Don't look ahead for punc; we are looking for one char only
atoms.Add(textSection[0].ToString(), default(ReadOnlySpan <char>));
}
else
{
atoms.Add(textSection.ToString(), LookAheadForPunc(latex, ref textSection));
}
break;
}
}
afterCommand = false;
}
//Escaped text section but in inline/display math mode
else if (displayMath != null)
{
switch (textSection)
{
case var _ when textSection.Is('$'):
throw new InvalidCodePathException("The $ case should have been accounted for.");
case var _ when textSection.Is('('):
switch (displayMath)
{
case true:
return("Cannot open inline math mode in display math mode");
case false:
return("Cannot open inline math mode in inline math mode");
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
case var _ when textSection.Is(')'):
switch (displayMath)
{
case true:
return("Cannot close inline math mode in display math mode");
case false:
if (atoms.Add(mathLaTeX.ToString(), false).Error is string mathError)
{
return("[Math mode error] " + mathError);
}
mathLaTeX = null;
displayMath = null;
break;
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
break;
case var _ when textSection.Is('['):
switch (displayMath)
{
case true:
return("Cannot open display math mode in display math mode");
case false:
return("Cannot open display math mode in inline math mode");
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
case var _ when textSection.Is(']'):
switch (displayMath)
{
case true:
if (atoms.Add(mathLaTeX.ToString(), true).Error is string mathError)
{
return("[Math mode error] " + mathError);
}
mathLaTeX = null;
displayMath = null;
break;
case false:
return("Cannot close display math mode in inline math mode");
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
break;
default:
mathLaTeX.Append('\\').Append(textSection);
break;
}
backslashEscape = false;
}
else
{
//Escaped text section and not in inline/display math mode
afterCommand = true;
switch (textSection)
{
case var _ when textSection.Is('('):
mathLaTeX = new StringBuilder();
displayMath = false;
break;
case var _ when textSection.Is(')'):
return("Cannot close inline math mode outside of math mode");
case var _ when textSection.Is('['):
mathLaTeX = new StringBuilder();
displayMath = true;
break;
case var _ when textSection.Is(']'):
return("Cannot close display math mode outside of math mode");
case var _ when textSection.Is('\\'):
atoms.Break(1);
break;
case var _ when textSection.Is(','):
atoms.Add(Space.ShortSpace, 1);
break;
case var _ when textSection.Is(':') || textSection.Is('>'):
atoms.Add(Space.MediumSpace, 1);
break;
case var _ when textSection.Is(';'):
atoms.Add(Space.LongSpace, 1);
break;
case var _ when textSection.Is('!'):
atoms.Add(-Space.ShortSpace, 1);
break;
case var _ when wordKind == WordKind.Whitespace: //control space
atoms.Add();
break;
case var _ when textSection.Is("par"):
ParagraphBreak();
break;
case var _ when textSection.Is("fontsize"): {
if (ReadArgumentString(latex, ref textSection).Bind(fontSize => {
if (fontSize.Length > StringArgumentLimit)
{
return(Err($"Length of font size has over {StringArgumentLimit} characters. Please shorten it."));
}
Span <byte> charBytes = stackalloc byte[fontSize.Length];
for (int j = 0; j < fontSize.Length; j++)
{
if (fontSize[j] > 127)
{
return(Err("Invalid font size"));
}
charBytes[j] = (byte)fontSize[j];
}
return(System.Buffers.Text.Utf8Parser.TryParse(charBytes, out float parsedResult, out _, 'f') ?
Ok(parsedResult) :
Err("Invalid font size"));
}).Bind(
ReadArgumentAtom(latex),
(fontSize, resizedContent) =>
atoms.Add(resizedContent, fontSize, "fontsize".Length)
).Error is string error
)
{
return(error);
}
break;
}
case var _ when textSection.Is("color"): {
if (ReadArgumentString(latex, ref textSection).Bind(color =>
color.Length > StringArgumentLimit ?
Err($"Length of color has over {StringArgumentLimit} characters. Please shorten it.") :
Color.Create(color, !NoEnhancedColors) is Color value ?
Ok(value) :
Err("Invalid color")
).Bind(
ReadArgumentAtom(latex),
(color, coloredContent) =>
atoms.Add(coloredContent, color, "color".Length)
).Error is string error
)
{
return(error);
}
break;
}
//case "red", "yellow", ...
case var shortColor when !NoEnhancedColors && shortColor.TryAccessDictionary(Color.PredefinedColors, out var color): {
int tmp_commandLength = shortColor.Length;
if (ReadArgumentAtom(latex).Bind(
coloredContent => atoms.Add(coloredContent, color, tmp_commandLength)
).Error is string error
)
{
return(error);
}
break;
}
//case "textbf", "textit", ...
bool ValidTextStyle(ReadOnlySpan <char> textStyle, out FontStyle fontStyle)
{
fontStyle = default;
if (textStyle.Length > 3 &&
textStyle[0] == 'm' &&
textStyle[1] == 'a' &&
textStyle[2] == 't' &&
textStyle[3] == 'h')
{
return(false);
}
Span <char> copy = stackalloc char[textStyle.Length];
textStyle.CopyTo(copy);
if (textStyle.Length > 3 &&
textStyle[0] == 't' &&
textStyle[1] == 'e' &&
textStyle[2] == 'x' &&
textStyle[3] == 't')
{
copy[0] = 'm';
copy[1] = 'a';
copy[2] = 't';
copy[3] = 'h';
}
return(((ReadOnlySpan <char>)copy).TryAccessDictionary(FontStyleExtensions.FontStyles, out fontStyle));
}
case var textStyle when ValidTextStyle(textStyle, out var fontStyle): {
int tmp_commandLength = textStyle.Length;
if (ReadArgumentAtom(latex)
.Bind(builtContent => atoms.Add(builtContent, fontStyle, tmp_commandLength))
.Error is string error)
{
return(error);
}
break;
}
//case "^", "\"", ...
case var textAccent when textAccent.TryAccessDictionary(TextAtoms.PredefinedAccents, out var accent): {
int tmp_commandLength = textAccent.Length;
if (ReadArgumentAtom(latex)
.Bind(builtContent => atoms.Add(builtContent, accent, tmp_commandLength))
.Error is string error)
{
return(error);
}
break;
}
//case "textasciicircum", "textless", ...
case var textSymbol when textSymbol.TryAccessDictionary(TextAtoms.PredefinedTextSymbols, out var replaceResult):
atoms.Add(replaceResult, LookAheadForPunc(latex, ref textSection));
break;
case var command:
if (displayMath != null)
{
mathLaTeX.Append(command); //don't eat the command when parsing math
}
else
{
return($@"Unknown command \{command.ToString()}");
}
break;
}
backslashEscape = false;
}
}
afterNewline = false;
if (oneCharOnly)
{
return(Ok(i));
}
}
if (backslashEscape)
{
return(@"Unknown command \");
}
if (stopChar > 0)
{
return(stopChar == '}' ? "Expected }, unbalanced braces" : $@"Expected {stopChar}");
}
return(Ok(i));
}
{ if (BuildBreakList(latexSource, globalAtoms, 0, false, '\0').Error is string error)
{
return(error);
}
}
{ if (CheckDollarCount(globalAtoms).Error is string error)
{
return(error);
}
}
if (displayMath != null)
{
return("Math mode was not terminated");
}
return(globalAtoms.Build());
}
/* //Paste this into the C# Interactive, fill <username> yourself
#r "C:/Users/<username>/source/repos/CSharpMath/Typography/Build/NetStandard/Typography.TextBreak/bin/Debug/netstandard1.3/Typography.TextBreak.dll"
using Typography.TextBreak;
(int, WordKind, char)[] BreakText(string text) {
var breaker = new CustomBreaker();
var breakList = new List<BreakAtInfo>();
breaker.BreakWords(text);
breaker.LoadBreakAtList(breakList);
//index is after the boundary -> last one will be out of range
return breakList.Select(i => (i.breakAt, i.wordKind, text.ElementAtOrDefault(i.breakAt))).ToArray();
}
BreakText(@"Here are some text $1 + 12 \frac23 \sqrt4$ $$Display$$ text")
*/
/* //Version 2
#r "C:/Users/<username>/source/repos/CSharpMath/Typography/Build/NetStandard/Typography.TextBreak/bin/Debug/netstandard1.3/Typography.TextBreak.dll"
using Typography.TextBreak;
string BreakText(string text, string seperator = "|")
{
var breaker = new CustomBreaker();
var breakList = new List<BreakAtInfo>();
breaker.BreakWords(text);
breaker.LoadBreakAtList(breakList);
//reverse to ensure earlier inserts do not affect later ones
foreach (var @break in breakList.Select(i => i.breakAt).Reverse())
text = text.Insert(@break, seperator);
return text;
}
BreakText(@"Here are some text $1 + 12 \frac23 \sqrt4$ $$Display$$ text")
*/
public static Result<TextAtom> Build(string text, bool enhancedColors) {
if (string.IsNullOrEmpty(text)) return new TextAtom.List(Array.Empty<TextAtom>(), 0);
bool? displayMath = null;
StringBuilder mathLaTeX = null;
bool backslashEscape = false;
bool afterCommand = false; //ignore spaces after command
int dollarCount = 0;
var atoms = new TextAtomListBuilder();
var breaker = new CustomBreaker();
var breakList = new List<BreakAtInfo>();
breaker.BreakWords(text, false);
breaker.LoadBreakAtList(breakList);
Result CheckDollarCount() {
switch (dollarCount) {
case 0:
break;
case 1:
dollarCount = 0;
switch (displayMath) {
case true:
return "Cannot close display math mode with $";
case false:
if (atoms.Add(mathLaTeX.ToString(), false).Error is string mathError)
return "[Math mode error] " + mathError;
mathLaTeX = null;
displayMath = null;
break;
case null:
mathLaTeX = new StringBuilder();
displayMath = false;
break;
}
break;
case 2:
dollarCount = 0;
switch (displayMath) {
case true:
if (atoms.Add(mathLaTeX.ToString(), true).Error is string mathError)
return "[Math mode error] " + mathError;
mathLaTeX = null;
displayMath = null;
break;
case false:
return "Cannot close inline math mode with $$";
case null:
mathLaTeX = new StringBuilder();
displayMath = true;
break;
}
break;
default:
return "Invalid number of $: " + dollarCount;
}
return Ok();
}
(int startAt, int endAt, char endingChar, WordKind wordKind) ObtainRange(int i) =>
(i == 0 ? 0 : breakList[i - 1].breakAt, breakList[i].breakAt, text[breakList[i].breakAt - 1], breakList[i].wordKind);
for (var i = 0; i < breakList.Count; i++) {
var (startAt, endAt, endingChar, wordKind) = ObtainRange(i);
bool SetNextRange() {
bool success = ++i < breakList.Count;
if(success) (startAt, endAt, endingChar, wordKind) = ObtainRange(i);
return success;
}
Result<string> ReadArgument() {
afterCommand = false;
if (!SetNextRange()) return Err("Missing argument");
if (endingChar != '{') {
var toReturn = text[startAt].ToString();
#warning Not one char only, should skip spaces then read next char, and it is a possible command
//range contains one char only
if (startAt == endAt)
_ = SetNextRange(); //reaching the end does not affect validity of argument
else
startAt += 1;
return Ok(toReturn);
}
int endingIndex = -1;
//startAt + 1 to not start at the { we started at
for (int j = startAt + 1, bracketDepth = 0; j < text.Length; j++) {
if (text[j] == '{') bracketDepth++;
else if (text[j] == '}')
if (bracketDepth > 0) bracketDepth--;
else { endingIndex = j; break; }
}
if (endingIndex == -1) return Err("Missing }");
var resultText = text.Substring(endAt, endingIndex - endAt);
while (startAt < endingIndex)
_ = SetNextRange(); //this never fails because the above check
return Ok(resultText);
}
atoms.TextLength = startAt;
if (endingChar == '$') {
if (backslashEscape)
if (displayMath != null) mathLaTeX.Append(@"\$");
else atoms.Add("$");
else {
dollarCount++;
continue;
}
backslashEscape = false;
} else {
{ if (CheckDollarCount().Error is string error) return error; }
//Normal unescaped text section, could be in display/inline math mode
if (!backslashEscape) {
var textSection = text.Substring(startAt, endAt - startAt);
switch (endingChar) {
case '$':
throw new InvalidCodePathException("The $ case should have been accounted for.");
case '\\':
backslashEscape = true;
continue;
case var sp when wordKind == WordKind.Whitespace || wordKind == WordKind.NewLine:
//Collpase spaces
//Consume newlines after commands
if (displayMath == null)
if (afterCommand) continue;
else atoms.Add();
else mathLaTeX.Append(textSection);
break;
case var punc when displayMath == null && wordKind == WordKind.Punc && atoms.Last is TextAtom.Text t:
//Append punctuation to text
t.Append(textSection);
break;
default: //Just ordinary text
if (displayMath == null) atoms.Add(textSection);
else mathLaTeX.Append(textSection);
break;
}
afterCommand = false;
continue;
}
//Escaped text section but in inline/display math mode
if (displayMath != null) {
switch (endingChar) {
case '$':
throw new InvalidCodePathException("The $ case should have been accounted for.");
case '(':
switch (displayMath) {
case true:
return "Cannot open inline math mode in display math mode";
case false:
return "Cannot open inline math mode in inline math mode";
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
case ')':
switch (displayMath) {
case true:
return "Cannot close inline math mode in display math mode";
case false:
if (atoms.Add(mathLaTeX.ToString(), false).Error is string mathError)
return "[Math mode error] " + mathError;
mathLaTeX = null;
displayMath = null;
break;
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
break;
case '[':
switch (displayMath) {
case true:
return "Cannot open display math mode in display math mode";
case false:
return "Cannot open display math mode in inline math mode";
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
case ']':
switch (displayMath) {
case true:
if (atoms.Add(mathLaTeX.ToString(), true).Error is string mathError)
return "[Math mode error] " + mathError;
mathLaTeX = null;
displayMath = null;
break;
case false:
return "Cannot close display math mode in inline math mode";
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
break;
default:
mathLaTeX.Append($@"\{text.Substring(startAt, endAt - startAt)}");
break;
}
backslashEscape = false;
continue;
}
//Escaped text section and not in inline/display math mode
afterCommand = true;
switch (text.Substring(startAt, endAt - startAt)) {
case "(":
mathLaTeX = new StringBuilder();
displayMath = false;
break;
case ")":
return "Cannot close inline math mode outside of math mode";
case "[":
mathLaTeX = new StringBuilder();
displayMath = true;
break;
case "]":
return "Cannot close display math mode outside of math mode";
case @"\":
atoms.Break(1);
break;
case ",":
atoms.Add(Space.ShortSpace, 1);
break;
case var _ when wordKind == WordKind.Whitespace: //control space
atoms.Add();
break;
case "backslash":
atoms.Add(@"\");
break;
case "par":
atoms.Break(3);
#warning Should the newline and space occupy the same range?
atoms.TextLength -= 3;
atoms.Add(Space.ParagraphIndent, 3);
break;
case "fontsize": {
if (ReadArgument().Bind(fontSize =>
float.TryParse(fontSize, System.Globalization.NumberStyles.AllowDecimalPoint |
System.Globalization.NumberStyles.AllowLeadingWhite |
System.Globalization.NumberStyles.AllowTrailingWhite,
System.Globalization.CultureInfo.InvariantCulture,
out var parsedResult) ?
Ok(parsedResult) :
Err("Invalid font size")
).Bind(
ReadArgument().Bind(resizedContent => Build(resizedContent, enhancedColors)),
(fontSize, resizedContent) =>
atoms.Add(resizedContent, fontSize, "fontsize".Length)
).Error is string error
) return error;
break;
}
case "color": {
if (ReadArgument().Bind(color =>
Color.Create(color, enhancedColors) is Color value ?
Ok(value) :
Err("Invalid color")
).Bind(
ReadArgument().Bind(coloredContent => Build(coloredContent, enhancedColors)),
(color, coloredContent) =>
atoms.Add(coloredContent, color, "color".Length)
).Error is string error
) return error;
break;
}
//case "red", "yellow", ...
case var shortColor when enhancedColors && Color.PredefinedColors.Contains(shortColor): {
if (Ok(Color.Create(shortColor, enhancedColors) ??
throw new InvalidCodePathException(
"This case's condition should have checked the validity of shortColor.")
).Bind(
ReadArgument().Bind(coloredContent => Build(coloredContent, enhancedColors)),
(color, coloredContent) =>
atoms.Add(coloredContent, color, shortColor.Length)
).Error is string error
) return error;
break;
}
//case "textbf", "textit", ...
case var command when !command.Contains("math") && FontStyleExtensions.FontStyles.TryGetByFirst(command.Replace("text", "math"), out var fontStyle): {
if (ReadArgument()
.Bind(content => Build(content, enhancedColors))
.Bind(builtContent => atoms.Add(builtContent, fontStyle, command.Length))
.Error is string error)
return error;
break;
}
case var command:
if (displayMath != null) mathLaTeX.Append(command); //don't eat the command when parsing math
else return @"Unknown command \" + command;
break;
}
backslashEscape = false;
}
}
{ if (CheckDollarCount().Error is string error) return error; }
if (backslashEscape) return @"Unknown command \";
if (displayMath != null) return "Math mode was not terminated";
return atoms.Build();
}
public static Result <TextAtom> Build(string latex)
{
if (string.IsNullOrEmpty(latex))
{
return(new TextAtom.List(Array.Empty <TextAtom>(), 0));
}
bool? displayMath = null;
StringBuilder mathLaTeX = null;
bool backslashEscape = false;
bool afterCommand = false; //ignore spaces after command
bool afterNewline = false;
int dollarCount = 0;
var globalAtoms = new TextAtomListBuilder();
var breaker = new CustomBreaker {
BreakNumberAfterText = true, ThrowIfCharOutOfRange = false
};
var breakList = new List <BreakAtInfo>();
breaker.BreakWords(latex);
breaker.CopyBreakResults(breakList);
Result CheckDollarCount(TextAtomListBuilder atoms)
{
switch (dollarCount)
{
case 0:
break;
case 1:
dollarCount = 0;
switch (displayMath)
{
case true:
return("Cannot close display math mode with $");
case false:
if (atoms.Add(mathLaTeX.ToString(), false).Error is string mathError)
{
return("[Math mode error] " + mathError);
}
mathLaTeX = null;
displayMath = null;
break;
case null:
mathLaTeX = new StringBuilder();
displayMath = false;
break;
}
break;
case 2:
dollarCount = 0;
switch (displayMath)
{
case true:
if (atoms.Add(mathLaTeX.ToString(), true).Error is string mathError)
{
return("[Math mode error] " + mathError);
}
mathLaTeX = null;
displayMath = null;
break;
case false:
return("Cannot close inline math mode with $$");
case null:
mathLaTeX = new StringBuilder();
displayMath = true;
break;
}
break;
default:
return("Invalid number of $: " + dollarCount);
}
return(Ok());
}
Result <int> BuildBreakList(TextAtomListBuilder atoms, int i, bool oneCharOnly, char stopChar)
{
void ParagraphBreak()
{
atoms.Break(3);
#warning Should the newline and space occupy the same range?
atoms.TextLength -= 3;
atoms.Add(Space.ParagraphIndent, 3);
}
for (; i < breakList.Count; i++)
{
(int startAt, int endAt, string textSection, WordKind wordKind) ObtainRange(int index)
{
var(start, end) = (index == 0 ? 0 : breakList[index - 1].breakAt, breakList[index].breakAt);
return(start, end, latex.Substring(start, end - start), breakList[index].wordKind);
}
var(startAt, endAt, textSection, wordKind) = ObtainRange(i);
bool SetNextRange()
{
bool success = ++i < breakList.Count;
if (success)
{
(startAt, endAt, textSection, wordKind) = ObtainRange(i);
}
return(success);
}
Result <TextAtom> ReadArgumentAtom()
{
backslashEscape = false;
var argAtoms = new TextAtomListBuilder();
if (BuildBreakList(argAtoms, ++i, true, '\0').Bind(index => i = index).Error is string error)
{
return(error);
}
return(argAtoms.Build());
}
Result <string> ReadArgumentString()
{
afterCommand = false;
if (!SetNextRange())
{
return(Err("Missing argument"));
}
if (textSection != "{")
{
return(Err("Missing {"));
}
int endingIndex = -1;
//startAt + 1 to not start at the { we started at
bool isEscape = false;
for (int j = startAt + 1, bracketDepth = 0; j < latex.Length; j++)
{
if (latex[j] == '\\')
{
isEscape = true;
}
else if (latex[j] == '{' && !isEscape)
{
bracketDepth++;
}
else if (latex[j] == '}' && !isEscape)
{
if (bracketDepth > 0)
{
bracketDepth--;
}
else
{
endingIndex = j; break;
}
}
else
{
isEscape = false;
}
}
if (endingIndex == -1)
{
return(Err("Missing }"));
}
var resultText = latex.Substring(endAt, endingIndex - endAt);
while (startAt < endingIndex)
{
_ = SetNextRange(); //this never fails because the above check
}
return(Ok(resultText));
}
atoms.TextLength = startAt;
if (stopChar > 0 && textSection[0] == stopChar)
{
return(Ok(i));
}
if (textSection == "$")
{
if (backslashEscape)
{
if (displayMath != null)
{
mathLaTeX.Append(@"\$");
}
else
{
atoms.Add("$");
}
}
else
{
dollarCount++;
continue;
}
backslashEscape = false;
}
else
{
{ if (CheckDollarCount(atoms).Error is string error)
{
return(error);
}
}
if (!backslashEscape)
{
//Unescaped text section, inside display/inline math mode
if (displayMath != null)
{
switch (textSection)
{
case "$":
throw new InvalidCodePathException("The $ case should have been accounted for.");
case "\\":
backslashEscape = true;
continue;
default:
mathLaTeX.Append(textSection);
break;
}
}
//Unescaped text section, not inside display/inline math mode
else
{
switch (textSection)
{
case "$":
throw new InvalidCodePathException("The $ case should have been accounted for.");
case "\\":
backslashEscape = true;
continue;
case "#":
return("Unexpected command argument reference character # outside of new command definition (currently unsupported)");
case "^":
case "_":
return($"Unexpected script indicator {textSection} outside of math mode");
case "&":
return($"Unexpected alignment tab character & outside of table environments");
case "~":
atoms.Add();
break;
case "%":
var comment = new StringBuilder();
while (SetNextRange() && wordKind != WordKind.NewLine)
{
comment.Append(textSection);
}
atoms.Comment(comment.ToString());
break;
case "{":
if (BuildBreakList(atoms, ++i, false, '}').Bind(index => i = index).Error is string error)
{
return(error);
}
break;
case "}":
return("Unexpected }, unbalanced braces");
case var _ when wordKind == WordKind.NewLine:
//Consume newlines after commands
//Double newline == paragraph break
if (afterNewline)
{
ParagraphBreak();
afterNewline = false;
break;
}
else
{
atoms.Add();
afterNewline = true;
continue;
}
case var _ when wordKind == WordKind.Whitespace:
//Collpase spaces
if (afterCommand)
{
continue;
}
else
{
atoms.Add();
}
break;
case var punc when wordKind == WordKind.Punc && atoms.Last is TextAtom.Text t:
//Append punctuation to text
t.Append(textSection);
break;
default: //Just ordinary text
if (oneCharOnly)
{
if (startAt + 1 < endAt) //Only re-read if current break span is more than 1 long
{
i--;
breakList[i] = new BreakAtInfo(breakList[i].breakAt + 1, breakList[i].wordKind);
}
atoms.Add(textSection[0].ToString());
}
else
{
atoms.Add(textSection);
}
break;
}
}
afterCommand = false;
}
//Escaped text section but in inline/display math mode
else if (displayMath != null)
{
switch (textSection)
{
case "$":
throw new InvalidCodePathException("The $ case should have been accounted for.");
case "(":
switch (displayMath)
{
case true:
return("Cannot open inline math mode in display math mode");
case false:
return("Cannot open inline math mode in inline math mode");
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
case ")":
switch (displayMath)
{
case true:
return("Cannot close inline math mode in display math mode");
case false:
if (atoms.Add(mathLaTeX.ToString(), false).Error is string mathError)
{
return("[Math mode error] " + mathError);
}
mathLaTeX = null;
displayMath = null;
break;
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
break;
case "[":
switch (displayMath)
{
case true:
return("Cannot open display math mode in display math mode");
case false:
return("Cannot open display math mode in inline math mode");
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
case "]":
switch (displayMath)
{
case true:
if (atoms.Add(mathLaTeX.ToString(), true).Error is string mathError)
{
return("[Math mode error] " + mathError);
}
mathLaTeX = null;
displayMath = null;
break;
case false:
return("Cannot close display math mode in inline math mode");
default:
throw new InvalidCodePathException("displayMath is null. This switch should not be hit.");
}
break;
default:
mathLaTeX.Append($@"\{textSection}");
break;
}
backslashEscape = false;
}
else
{
//Escaped text section and not in inline/display math mode
afterCommand = true;
switch (textSection)
{
case "(":
mathLaTeX = new StringBuilder();
displayMath = false;
break;
case ")":
return("Cannot close inline math mode outside of math mode");
case "[":
mathLaTeX = new StringBuilder();
displayMath = true;
break;
case "]":
return("Cannot close display math mode outside of math mode");
case @"\":
atoms.Break(1);
break;
case ",":
atoms.Add(Space.ShortSpace, 1);
break;
case var _ when wordKind == WordKind.Whitespace: //control space
atoms.Add();
break;
case "par":
ParagraphBreak();
break;
case "fontsize": {
if (ReadArgumentString().Bind(fontSize =>
float.TryParse(fontSize, System.Globalization.NumberStyles.AllowDecimalPoint |
System.Globalization.NumberStyles.AllowLeadingWhite |
System.Globalization.NumberStyles.AllowTrailingWhite,
System.Globalization.CultureInfo.InvariantCulture,
out var parsedResult) ?
Ok(parsedResult) :
Err("Invalid font size")
).Bind(
ReadArgumentAtom(),
(fontSize, resizedContent) =>
atoms.Add(resizedContent, fontSize, "fontsize".Length)
).Error is string error
)
{
return(error);
}
break;
}
case "color": {
if (ReadArgumentString().Bind(color =>
Color.Create(color, !NoEnhancedColors) is Color value ?
Ok(value) :
Err("Invalid color")
).Bind(
ReadArgumentAtom(),
(color, coloredContent) =>
atoms.Add(coloredContent, color, "color".Length)
).Error is string error
)
{
return(error);
}
break;
}
//case "red", "yellow", ...
case var shortColor when !NoEnhancedColors && Color.PredefinedColors.Contains(shortColor): {
if (Ok(Color.Create(shortColor, !NoEnhancedColors) ??
throw new InvalidCodePathException(
"This case's condition should have checked the validity of shortColor.")
).Bind(
ReadArgumentAtom(),
(color, coloredContent) =>
atoms.Add(coloredContent, color, shortColor.Length)
).Error is string error
)
{
return(error);
}
break;
}
//case "textbf", "textit", ...
case var textStyle when !textStyle.Contains("math") && FontStyleExtensions.FontStyles.TryGetByFirst(textStyle.Replace("text", "math"), out var fontStyle): {
if (ReadArgumentAtom()
.Bind(builtContent => atoms.Add(builtContent, fontStyle, textStyle.Length))
.Error is string error)
{
return(error);
}
break;
}
//case "^", "\"", ...
case var textAccent when TextAtoms.PredefinedAccents.TryGetByFirst(textAccent, out var accent): {
if (ReadArgumentAtom()
.Bind(builtContent => atoms.Add(builtContent, accent, textAccent.Length))
.Error is string error)
{
return(error);
}
break;
}
//case "textasciicircum", "textless", ...
case var textSymbol when TextAtoms.PredefinedTextSymbols.TryGetValue(textSymbol, out var replaceResult):
atoms.Add(replaceResult);
break;
case var command:
if (displayMath != null)
{
mathLaTeX.Append(command); //don't eat the command when parsing math
}
else
{
return(@"Unknown command \" + command);
}
break;
}
backslashEscape = false;
}
}
afterNewline = false;
if (oneCharOnly)
{
return(Ok(i));
}
}
if (backslashEscape)
{
return(@"Unknown command \");
}
if (stopChar > 0)
{
return(stopChar == '}' ? "Expected }, unbalanced braces" : $@"Expected {stopChar}");
}
return(Ok(i));
}
{ if (BuildBreakList(globalAtoms, 0, false, '\0').Error is string error)
{
return(error);
}
}
{ if (CheckDollarCount(globalAtoms).Error is string error)
{
return(error);
}
}
if (displayMath != null)
{
return("Math mode was not terminated");
}
return(globalAtoms.Build());
}
