Plex/proxy/src/main/java/dev/plex/toml/Keys.java

package dev.plex.toml;

import java.util.ArrayList;
import java.util.List;

class Keys
{

    static class Key
    {
        final String name;
        final int index;
        final String path;

        Key(String name, int index, Key next)
        {
            this.name = name;
            this.index = index;
            if (next != null)
            {
                this.path = name + "." + next.path;
            }
            else
            {
                this.path = name;
            }
        }
    }

    static Key[] split(String key)
    {
        List<Key> splitKey = new ArrayList<Key>();
        StringBuilder current = new StringBuilder();
        boolean quoted = false;
        boolean indexable = true;
        boolean inIndex = false;
        int index = -1;

        for (int i = key.length() - 1; i > -1; i--)
        {
            char c = key.charAt(i);
            if (c == ']' && indexable)
            {
                inIndex = true;
                continue;
            }
            indexable = false;
            if (c == '[' && inIndex)
            {
                inIndex = false;
                index = Integer.parseInt(current.toString());
                current = new StringBuilder();
                continue;
            }
            if (isQuote(c) && (i == 0 || key.charAt(i - 1) != '\\'))
            {
                quoted = !quoted;
                indexable = false;
            }
            if (c != '.' || quoted)
            {
                current.insert(0, c);
            }
            else
            {
                splitKey.add(0, new Key(current.toString(), index, !splitKey.isEmpty() ? splitKey.get(0) : null));
                indexable = true;
                index = -1;
                current = new StringBuilder();
            }
        }

        splitKey.add(0, new Key(current.toString(), index, !splitKey.isEmpty() ? splitKey.get(0) : null));

        return splitKey.toArray(new Key[0]);
    }

    static boolean isQuote(char c)
    {
        return c == '"' || c == '\'';
    }

    private Keys()
    {
    }
}