package com.vincent.rsf.server.manager.utils;

import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import com.google.gson.JsonObject;
import lombok.Data;

import java.util.*;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.stream.Collectors;

/**
 * @author Ryan
 * @description 根据对象多个属性合并处理
 * @param
 * @return
 * @time 2025/4/25 10:55
 */
public class GroupMergeUtil {
    /**
     * 根据多个属性分组合并对象列表
     *
     * @param list       待分组的对象列表
     * @param mergers    合并函数，定义如何合并同一组中的对象
     * @param keyGetters 分组属性的getter方法数组
     * @param <T>        对象类型
     * @param <K>        分组键类型
     * @return 分组合并后的对象列表
     */
    @SafeVarargs
    public static <T, K> List<T> groupAndMerge(
            List<T> list,
            BinaryOperator<T> mergers,
            Function<T, K>... keyGetters) {

        return new ArrayList<>(list.stream()
                .collect(Collectors.toMap(
                        item -> new GroupingKeys<>(Arrays.stream(keyGetters)
                                .map(getter -> getter.apply(item))
                                .toArray()),
                        Function.identity(),
                        mergers))
                .values());
    }

    /**
     * @author Ryan
     * @description 用于存储多个分组键的内部类
     * @param
     * @return
     * @time 2025/4/25 10:56
     */
    private static class GroupingKeys<K> {
        private final Object[] keys;
        private final int hashCode;

        public GroupingKeys(Object[] keys) {
            this.keys = keys;
            this.hashCode = Arrays.deepHashCode(keys);
        }

        @Override
        public boolean equals(Object o) {
            if (this == o) {
                return true;
            }
            if (o == null || getClass() != o.getClass()) {
                return false;
            }
            GroupingKeys<?> that = (GroupingKeys<?>) o;
            return Arrays.deepEquals(keys, that.keys);
        }

        @Override
        public int hashCode() {
            return hashCode;
        }
    }

    // 示例使用
//    public static void main(String[] args) {
//        // 示例数据类
//        @Data
//        class Product {
//         private String category;
//            private String subCategory;
//            private String abc;
//
//            private String dbc;
//
//            private String brand;
//            private int quantity;
//            private double price;
//
//            public Product(String category, String abc, String dbc, String subCategory, String brand, int quantity, double price) {
//                this.category = category;
//                this.subCategory = subCategory;
//                this.abc = abc;
//                this.dbc = dbc;
//                this.brand = brand;
//                this.quantity = quantity;
//                this.price = price;
//            }
//
//            // getters...
////            public String getCategory() { return category; }
////            public String getSubCategory() { return subCategory; }
////            public String getBrand() { return brand; }
////            public int getQuantity() { return quantity; }
////            public double getPrice() { return price; }
//
//            @Override
//            public String toString() {
//                return String.format("[%s, %s, %s] - Qty: %d, Price: %.2f",
//                        category, subCategory, brand, quantity, price);
//            }
//        }
//
//        // 创建测试数据
//        List<Product> products = Arrays.asList(
//                new Product("Electronics", "Phone", "Apple", 10, 999.99),
//                new Product("Electronics", "Phone", "Samsung", 15, 899.99),
//                new Product("Electronics", "Phone", "Apple", 5, 999.99),
//                new Product("Electronics", "Tablet", "Apple", 8, 799.99),
//                new Product("Clothing", "Shirt", "Nike", 20, 29.99),
//                new Product("Clothing", "Shirt", "Nike", 10, 29.99),
//                new Product("Clothing", "Pants", "Adidas", 12, 49.99)
//        );
//
//        // 按 category, subCategory, brand 分组，合并 quantity 相加，price 取平均值
//        List<Product> mergedProducts = groupAndMerge(
//                products,
//                (p1, p2) -> new Product(
//                        p1.category,
//                        p1.subCategory,
//                        p1.brand,
//                        p1.quantity + p2.quantity,
//                        (p1.price + p2.price) / 2  // 这里简单平均，实际业务可能不同
//                ),
//                Product::getCategory,
//                Product::getSubCategory,
//                Product::getBrand
//        );
//
////        // 打印结果
////        System.out.println("合并后的产品列表:");
////        System.out.println(JSONArray.toJSONString(mergedProducts));
////        mergedProducts.forEach(item -> {
////            System.out.println(JSONObject.toJSONString(item));
////        });
////        mergedProducts.forEach(System.out::println);
//    }
}