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package org.macrocloud.kernel.toolkit.utils;

import org.springframework.lang.Nullable;
import org.springframework.util.CollectionUtils;

import java.lang.reflect.Array;
import java.util.*;
import java.util.stream.Collectors;


/**
 * 集合工具类.
 *
 * @author macro
 */
public class CollectionUtil extends CollectionUtils {

	/**
	 * Return {@code true} if the supplied Collection is not {@code null} or empty.
	 * Otherwise, return {@code false}.
	 *
	 * @param collection the Collection to check
	 * @return whether the given Collection is not empty
	 */
	public static boolean isNotEmpty(@Nullable Collection collection) {
		return !CollectionUtil.isEmpty(collection);
	}

	/**
	 * Return {@code true} if the supplied Map is not {@code null} or empty.
	 * Otherwise, return {@code false}.
	 *
	 * @param map the Map to check
	 * @return whether the given Map is not empty
	 */
	public static boolean isNotEmpty(@Nullable Map map) {
		return !CollectionUtil.isEmpty(map);
	}

	/**
	 * Check whether the given Array contains the given element.
	 *
	 * @param      The generic tag
	 * @param array   the Array to check
	 * @param element the element to look for
	 * @return {@code true} if found, {@code false} else
	 */
	public static  boolean contains(@Nullable T[] array, final T element) {
		if (array == null) {
			return false;
		}
		return Arrays.stream(array).anyMatch(x -> ObjectUtil.nullSafeEquals(x, element));
	}

	/**
	 * Concatenates 2 arrays.
	 *
	 * @param one   数组1
	 * @param other 数组2
	 * @return 新数组
	 */
	public static String[] concat(String[] one, String[] other) {
		return concat(one, other, String.class);
	}

	/**
	 * Concatenates 2 arrays.
	 *
	 * @param  the generic type
	 * @param one   数组1
	 * @param other 数组2
	 * @param clazz 数组类
	 * @return 新数组
	 */
	public static  T[] concat(T[] one, T[] other, Class clazz) {
		T[] target = (T[]) Array.newInstance(clazz, one.length + other.length);
		System.arraycopy(one, 0, target, 0, one.length);
		System.arraycopy(other, 0, target, one.length, other.length);
		return target;
	}

	/**
	 * 对象是否为数组对象.
	 *
	 * @param obj 对象
	 * @return 是否为数组对象，如果为{@code null} 返回false
	 */
	public static boolean isArray(Object obj) {
		if (null == obj) {
			return false;
		}
		return obj.getClass().isArray();
	}

	/**
	 * 不可变 Set.
	 *
	 * @param  泛型
	 * @param es  对象
	 * @return 集合
	 */
	@SafeVarargs
	public static  Set ofImmutableSet(E... es) {
		Objects.requireNonNull(es, "args es is null.");
		return Arrays.stream(es).collect(Collectors.toSet());
	}

	/**
	 * 不可变 List.
	 *
	 * @param  泛型
	 * @param es  对象
	 * @return 集合
	 */
	@SafeVarargs
	public static  List ofImmutableList(E... es) {
		Objects.requireNonNull(es, "args es is null.");
		return Arrays.stream(es).collect(Collectors.toList());
	}

	/**
	 * Iterable 转换为List集合.
	 *
	 * @param       泛型
	 * @param elements Iterable
	 * @return 集合
	 */
	public static  List toList(Iterable elements) {
		Objects.requireNonNull(elements, "elements es is null.");
		if (elements instanceof Collection) {
			return new ArrayList((Collection) elements);
		}
		Iterator iterator = elements.iterator();
		List list = new ArrayList<>();
		while (iterator.hasNext()) {
			list.add(iterator.next());
		}
		return list;
	}

	/**
	 * 将key value 数组转为 map.
	 *
	 * @param         key
	 * @param         value
	 * @param keysValues key value 数组
	 * @return map 集合
	 */
	public static  Map toMap(Object... keysValues) {
		int kvLength = keysValues.length;
		if (kvLength % 2 != 0) {
			throw new IllegalArgumentException("wrong number of arguments for met, keysValues length can not be odd");
		}
		Map keyValueMap = new HashMap<>(kvLength);
		for (int i = kvLength - 2; i >= 0; i -= 2) {
			Object key = keysValues[i];
			Object value = keysValues[i + 1];
			keyValueMap.put((K) key, (V) value);
		}
		return keyValueMap;
	}

}