package launcher.serialize.config.entry;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.stream.Stream;

import launcher.LauncherAPI;
import launcher.serialize.HInput;
import launcher.serialize.HOutput;

public final class ListConfigEntry extends ConfigEntry<List<ConfigEntry<?>>> {
	@LauncherAPI
	public ListConfigEntry(List<ConfigEntry<?>> value, boolean ro, int cc) {
		super(value, ro, cc);
	}

	@LauncherAPI
	public ListConfigEntry(HInput input, boolean ro) throws IOException {
		super(readList(input, ro), ro, 0);
	}

	@Override
	public Type getType() {
		return Type.LIST;
	}

	@Override
	public void write(HOutput output) throws IOException {
		List<ConfigEntry<?>> value = getValue();
		output.writeLength(value.size(), 0);
		for (ConfigEntry<?> element : value) {
			writeEntry(element, output);
		}
	}

	@Override
	protected void uncheckedSetValue(List<ConfigEntry<?>> value) {
		List<ConfigEntry<?>> list = new ArrayList<>(value);
		super.uncheckedSetValue(ro ? Collections.unmodifiableList(list) : list);
	}

	@LauncherAPI
	public <V, E extends ConfigEntry<V>> Stream<V> stream(Class<E> clazz) {
		return getValue().stream().map(clazz::cast).map(ConfigEntry::getValue);
	}

	@LauncherAPI
	public void verifyOfType(Type type) {
		if (getValue().stream().anyMatch(e -> e.getType() != type)) {
			throw new IllegalArgumentException("List type mismatch: " + type.name());
		}
	}

	private static List<ConfigEntry<?>> readList(HInput input, boolean ro) throws IOException {
		int elementsCount = input.readLength(0);
		List<ConfigEntry<?>> list = new ArrayList<>(elementsCount);
		for (int i = 0; i < elementsCount; i++) {
			list.add(readEntry(input, ro));
		}
		return list;
	}
}