AdventDay5.java

package org.example;

import org.w3c.dom.ranges.Range;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.*;
import java.util.function.Function;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import java.util.stream.Stream;

public class AdventDay5 {

    public static String getLinesInFile(String path) throws FileNotFoundException {
        String lines = new String();

        Scanner scan = new Scanner(new File(path));
        try {
            while (true)
                lines += scan.nextLine() + "\n";
        }
        catch (Exception ignored) {
            // eof
        }
        scan.close();
        return lines;
    }

    public static String getLetterInRow(String rowStr, int pos)
    {
        int start = (rowStr.length() >= 4 ? 4 : 3) * pos + 1;
        if (rowStr.length() < start)
            return "";
        return rowStr.substring(start).substring(0, 1).trim();
    }

    public static HashMap<Integer, ArrayList<String>> crates = new HashMap<>();

    public static void printStorage()
    {
        boolean nextLine = false;
        for (int y = 24; y >= 0; y--) {
            for (int x = 0; x < crates.size(); x++) {
                var crate = crates.get(x);
                if (y < crate.size())
                {
                    System.out.print("[" + crate.get(y) + "] ");
                    nextLine = true;
                }
                else if (y >= crate.size())
                {
                    System.out.print("    ");
                    nextLine = true;
                }
            }

            if (nextLine)
                System.out.println();

            nextLine = false;
        }

        for (int i = 1; i <= crates.size(); i++)
            System.out.print(" " + i + "  ");

        System.out.println();
    }

    public static void parseStorage(String linesStorage[])
    {
        String lastLine = linesStorage[linesStorage.length - 1];
        Integer lastNum = Integer.parseInt(lastLine.substring(lastLine.length() - 2, lastLine.length()).trim());

        for (int i = 0; i < lastNum; i++)
            crates.put(i, new ArrayList<>());

        for (int i = linesStorage.length - 1 - 1; i >= 0; i--)
        {
            for (int pos = 0; pos < lastNum; pos++)
            {
                String letter = getLetterInRow(linesStorage[i], pos);
                if (!letter.isEmpty())
                    crates.get(pos).add(letter);
            }
        }
    }

    public static void parseMovements(String linesMovement[])
    {
        Pattern pattern = Pattern.compile("(\\d+)+");
        for (int i = 0; i < linesMovement.length; i++)
        {
            Matcher matcher = pattern.matcher(linesMovement[i]);

            matcher.find();
            Integer crateNum = Integer.parseInt(matcher.group(0));
            matcher.find();
            Integer fromNum = Integer.parseInt(matcher.group(0)) - 1;
            matcher.find();
            Integer toNum = Integer.parseInt(matcher.group(0)) - 1;

            System.out.println("---------------------------------------------------------");

            printStorage();

            ArrayList<String> crateList = crates.get(fromNum);
            System.out.println(" -------------------- move " + crateNum + " from " + (fromNum+1) + " to " + (toNum+1) + " (" + (crateList.size() + ", " + crateNum) + ")");


            List<String> subList = crateList.subList(crateList.size() - crateNum, crateList.size());
            Collections.reverse(subList);
            crates.get(toNum).addAll(subList);

            for (int j = 0; j < crateNum; j++)
                crates.get(fromNum).remove(crateList.size() - 1);

            printStorage();
        }
    }

    public static void main(String[] args) throws FileNotFoundException {
        String lines = getLinesInFile("day5.txt");

        String storage[] = lines.split("\n\n");

        parseStorage(storage[0].split("\n"));

        parseMovements(storage[1].split("\n"));

        printStorage();
    }
}