inkblot/InkBlot/InkBlotParser.cs

using Antlr4.Runtime;
using Antlr4.Runtime.Atn;
using Antlr4.Runtime.Tree;
using InkBlot.ParseHierarchy;
using InkBlot.Visitor;
using Microsoft.Extensions.Logging;

namespace InkBlot;

public class InkBlotParser
{
    public static (Story, IEnumerable<Diagnostic>) Parse(IFileReader fileReader, ILoggerFactory loggerFactory,
        string mainFileName)
    {
        var tokens = GetTokenStream(fileReader, mainFileName, out var lexerErrorListener);

        var parser = new InkBlotAntlrGrammarParser(tokens);
        var parserErrorListener = new ParserErrorListener();
        parser.RemoveErrorListeners();
        parser.AddErrorListener(parserErrorListener);
#if DEBUG
        parser.AddErrorListener(new DiagnosticErrorListener());
        parser.Interpreter.PredictionMode = PredictionMode.LL_EXACT_AMBIG_DETECTION;
#endif
        var tree = parser.story();
        var listener = new Listener(loggerFactory.CreateLogger<Listener>());
        var walker = new ParseTreeWalker();
        walker.Walk(listener, tree);
        return (listener.Story, lexerErrorListener.Diagnostics.Concat(parserErrorListener.Diagnostics));
    }

    private static CommonTokenStream GetTokenStream(IFileReader fileReader, string mainFileName,
        out LexerErrorListener lexerErrorListener)
    {
        var stream = fileReader.GetContents(mainFileName);
        var inputStream = new AntlrInputStream(stream);
        var lexer = new InkBlotAntlrGrammarLexer(inputStream);
        lexerErrorListener = new LexerErrorListener();
        lexer.RemoveErrorListeners();
        lexer.AddErrorListener(lexerErrorListener);
        var tokens = new CommonTokenStream(lexer);
        return tokens;
    }

    public static CommonTokenStream GetTokenStream(IFileReader fileReader, string mainFileName)
    {
        return GetTokenStream(fileReader, mainFileName, out _);
    }
}