/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the "Elastic License
 * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
 * Public License v 1"; you may not use this file except in compliance with, at
 * your election, the "Elastic License 2.0", the "GNU Affero General Public
 * License v3.0 only", or the "Server Side Public License, v 1".
 */

package org.elasticsearch.injection.guice;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;

public class ModulesBuilder implements Iterable<Module> {

    private final List<Module> modules = new ArrayList<>();

    public ModulesBuilder add(Module... newModules) {
        Collections.addAll(modules, newModules);
        return this;
    }

    public <T> T bindToInstance(Class<T> cls, T instance) {
        modules.add(b -> b.bind(cls).toInstance(instance));
        return instance;
    }

    @Override
    public Iterator<Module> iterator() {
        return modules.iterator();
    }

    public Injector createInjector() {
        Injector injector = Guice.createInjector(modules);
        ((InjectorImpl) injector).clearCache();
        // in ES, we always create all instances as if they are eager singletons
        // this allows for considerable memory savings (no need to store construction info) as well as cycles
        ((InjectorImpl) injector).readOnlyAllSingletons();
        return injector;
    }
}