using Nub.Lang;
using Nub.Lang.Frontend;
using Nub.Lang.Frontend.Generation;
using Nub.Lang.Frontend.Lexing;
using Nub.Lang.Frontend.Parsing;
using Nub.Lang.Frontend.Typing;

if (args.Length != 1)
{
    Console.Error.WriteLine("Usage:     nub <input-dir>");
    Console.Error.WriteLine("Example:   nub src");
    return 1;
}

var srcDir = Path.GetFullPath(args[0]);

if (!Directory.Exists(srcDir))
{
    Console.Error.WriteLine($"Error: Input directory '{srcDir}' does not exist.");
    return 1;
}

var error = false;

List<CompilationUnit> compilationUnits = [];

foreach (var file in Directory.EnumerateFiles(srcDir, "*.nub", SearchOption.AllDirectories))
{
    var content = File.ReadAllText(file);

    var tokenizeResult = Lexer.Tokenize(new SourceText(file, content));
    tokenizeResult.PrintAllDiagnostics();
    error = error || tokenizeResult.HasErrors;

    var parseResult = Parser.ParseFile(tokenizeResult.Value);
    parseResult.PrintAllDiagnostics();
    error = error || parseResult.HasErrors;

    if (parseResult.Value != null)
    {
        compilationUnits.Add(parseResult.Value);
    }
}

if (error)
{
    return 1;
}

var definitionTable = new DefinitionTable(compilationUnits);

foreach (var compilationUnit in compilationUnits)
{
    var typeCheckResult = TypeChecker.Check(compilationUnit, definitionTable);
    typeCheckResult.PrintAllDiagnostics();
    error = error || typeCheckResult.HasErrors;

    var result = QBEGenerator.Generate(compilationUnit, definitionTable);

    File.WriteAllText($"bin-int/{Guid.NewGuid():N}.ssa", result);
}

return error ? 1 : 0;