public void EngEngine()
{
//Text source: https://en.wikibooks.org/wiki/French/Texts/Simple/Le_Corbeau_et_le_Renard
const string Le_Corbeau_et_le_Renard = @"
Maître Corbeau, sur un arbre perché,
Tenait en son bec un fromage.
Maître Renard, par l’odeur alléché,
Lui tint à peu près ce langage :
« Hé ! bonjour, Monsieur du Corbeau.
Que vous êtes joli ! Que vous me semblez beau !
Sans mentir, si votre ramage
Se rapporte à votre plumage,
Vous êtes le Phénix des hôtes de ces bois. »
A ces mots le Corbeau ne se sent pas de joie ;
Et pour montrer sa belle voix,
Il ouvre un large bec, laisse tomber sa proie.
Le Renard s’en saisit, et dit : « Mon bon Monsieur,
Apprenez que tout flatteur
Vit aux dépens de celui qui l’écoute :
Cette leçon vaut bien un fromage, sans doute. »
Le Corbeau, honteux et confus,
Jura, mais un peu tard, qu’on ne l’y prendrait plus.";
const string Le_Corbeau_et_le_Renard__Broken = @"
|Maître| |Corbeau|,| |sur| |un| |arbre| |perché|,|
|Tenait| |en| |son| |bec| |un| |fromage.|
|Maître| |Renard|,| |par| |l|’|odeur| |alléché|,|
|Lui| |tint| |à| |peu| |près| |ce| |langage| |:|
|«| |Hé| |!| |bonjour|,| |Monsieur| |du| |Corbeau.|
|Que| |vous| |êtes| |joli| |!| |Que| |vous| |me| |semblez| |beau| |!|
|Sans| |mentir|,| |si| |votre| |ramage|
|Se| |rapporte| |à| |votre| |plumage|,|
|Vous| |êtes| |le| |Phénix| |des| |hôtes| |de| |ces| |bois.| |»|
|A| |ces| |mots| |le| |Corbeau| |ne| |se| |sent| |pas| |de| |joie| |;|
|Et| |pour| |montrer| |sa| |belle| |voix|,|
|Il| |ouvre| |un| |large| |bec|,| |laisse| |tomber| |sa| |proie.|
|Le| |Renard| |s|’|en| |saisit|,| |et| |dit| |:| |«| |Mon| |bon| |Monsieur|,|
|Apprenez| |que| |tout| |flatteur|
|Vit| |aux| |dépens| |de| |celui| |qui| |l|’|écoute| |:|
|Cette| |leçon| |vaut| |bien| |un| |fromage|,| |sans| |doute.| |»|
|Le| |Corbeau|,| |honteux| |et| |confus|,|
|Jura|,| |mais| |un| |peu| |tard|,| |qu|’|on| |ne| |l|’|y| |prendrait| |plus.|";
string BreakText(string text, string seperator = "|")
{
var breaker = new CustomBreaker { ThrowIfCharOutOfRange = true };
var breakList = new List<BreakAtInfo>();
#warning Use `breaker.BreakWords(text, breakList);` once #156 is merged
breaker.BreakWords(text);
breaker.CopyBreakResults(breakList);
var sb = new StringBuilder(text);
//reverse to ensure earlier inserts do not affect later ones
foreach (var @break in breakList.Select(i => i.breakAt).Reverse())
sb = sb.Insert(@break, seperator);
return sb.ToString();
}
var brokenString = BreakText(Le_Corbeau_et_le_Renard);
Assert.AreEqual(Le_Corbeau_et_le_Renard__Broken, brokenString);
}
public void BasicTest(string input, string[] output, bool breakNumberAfterText = false)
{
var customBreaker = new CustomBreaker();
customBreaker.BreakNumberAfterText = breakNumberAfterText;
//
customBreaker.BreakWords(input);
//
var outputList = new List <int> {
0
};
customBreaker.CopyBreakResults(outputList);
for (int i = 0; i < outputList.Count - 1; i++)
{
Assert.AreEqual
(
output[i],
input.Substring(outputList[i], outputList[i + 1] - outputList[i])
);
}
}
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());
}