LuaScript/src/main/java/org/openautonomousconnection/luascript/events/JavaToLua.java

package org.openautonomousconnection.luascript.events;

import org.luaj.vm2.LuaTable;
import org.luaj.vm2.LuaValue;

import java.util.List;
import java.util.Map;

/**
 * Coerces common Java values into Lua values.
 */
public final class JavaToLua {

    private JavaToLua() {
    }

    public static LuaValue coerce(Object v) {
        if (v == null) return LuaValue.NIL;
        if (v instanceof LuaValue lv) return lv;
        if (v instanceof String s) return LuaValue.valueOf(s);
        if (v instanceof Boolean b) return LuaValue.valueOf(b);
        if (v instanceof Integer i) return LuaValue.valueOf(i);
        if (v instanceof Long l) return LuaValue.valueOf(l);
        if (v instanceof Float f) return LuaValue.valueOf(f);
        if (v instanceof Double d) return LuaValue.valueOf(d);

        if (v instanceof Map<?, ?> m) {
            LuaTable t = new LuaTable();
            for (Map.Entry<?, ?> e : m.entrySet()) {
                Object k = e.getKey();
                if (k == null) continue;
                t.set(String.valueOf(k), coerce(e.getValue()));
            }
            return t;
        }

        if (v instanceof List<?> list) {
            LuaTable t = new LuaTable();
            int i = 1;
            for (Object o : list) {
                t.set(i++, coerce(o));
            }
            return t;
        }

        return LuaValue.valueOf(String.valueOf(v));
    }
}