package org.shedlang.compiler;

import org.shedlang.compiler.parser.Parser;
import org.shedlang.compiler.sources.Sources;

import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.SimpleFileVisitor;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.List;

import static org.shedlang.compiler.parser.Tokeniser.tokenise;

public class ShedCompiler {
    public void compile(Path projectRoot) throws IOException {
        var sourceRoot = projectRoot.resolve("src");

        var sourceFilePaths = collectSourceFilePaths(sourceRoot);

        for (var sourceFilePath : sourceFilePaths) {
            System.out.println(sourceFilePath);

            var sourceContents = Files.readString(sourceFilePath, StandardCharsets.UTF_8);
            var source = Sources.file(sourceFilePath.toString(), sourceContents);
            var tokens = tokenise(source);
            var node = Parser.parseNamespace(tokens);
            System.out.println(node);

            System.out.println();
        }
    }

    private List<Path> collectSourceFilePaths(Path sourceRoot) throws IOException {
        var paths = new ArrayList<Path>();
        Files.walkFileTree(sourceRoot, new SimpleFileVisitor<Path>() {
            @Override
            public FileVisitResult visitFile(
                Path file,
                BasicFileAttributes attrs
            ) {
                if (file.getFileName().toString().endsWith(".shed")) {
                    paths.add(file);
                }
                return FileVisitResult.CONTINUE;
            }

            @Override
            public FileVisitResult postVisitDirectory(
                Path dir,
                IOException exc
            ) {
                return FileVisitResult.CONTINUE;
            }
        });
        paths.sort(Comparator.naturalOrder());
        return paths;
    }
}