package com.zy.asrs.utils;

import java.util.*;

public class GroupedLockerOptimizerUtils {

    public static class Item {
        String name;
        double unitSpace;
        int maxCapacity;
        int stock;
        int remaining;

        public Item(String name, int maxCapacity, int stock) {
            this.name = name;
            this.maxCapacity = maxCapacity;
            this.unitSpace = 1.0 / maxCapacity;
            this.stock = stock;
            this.remaining = stock;
        }

        @Override
        public String toString() {
            return name + "(单放" + maxCapacity + "个, 库存" + stock + "个)";
        }
    }

    static class Locker {
        int id;
        double remainingSpace;
        Map<String, Integer> contents;
        Set<String> itemTypes; // 当前储物柜中的物品种类

        public Locker(int id) {
            this.id = id;
            this.remainingSpace = 1.0;
            this.contents = new HashMap<>();
            this.itemTypes = new HashSet<>();
        }

        public boolean canAdd(Item item, int quantity) {
            return remainingSpace >= quantity * item.unitSpace;
        }

        public void addItem(Item item, int quantity) {
            double spaceUsed = quantity * item.unitSpace;
            remainingSpace -= spaceUsed;
            contents.put(item.name, contents.getOrDefault(item.name, 0) + quantity);
            itemTypes.add(item.name);
            item.remaining -= quantity;
        }

        // 检查是否已经包含该种类的物品
        public boolean containsItemType(String itemName) {
            return itemTypes.contains(itemName);
        }

        // 检查是否可以优先放置同种物品（已有同种物品且还有空间）
        public boolean canAddSameType(Item item) {
            return containsItemType(item.name) && canAdd(item, 1);
        }

        @Override
        public String toString() {
            StringBuilder sb = new StringBuilder();
            sb.append("储物柜").append(id).append(": ");
            sb.append(String.format("剩余空间%.4f", remainingSpace)).append("\n");
            for (Map.Entry<String, Integer> entry : contents.entrySet()) {
                sb.append("  ").append(entry.getKey()).append(": ").append(entry.getValue()).append("个\n");
            }
            return sb.toString();
        }
    }

    static class PackingSolution {
        List<Locker> lockers;
        int totalLockersUsed;
        double overallUtilization;
        int itemTypeChanges; // 物品种类切换次数（衡量集中度）

        public PackingSolution() {
            this.lockers = new ArrayList<>();
        }

        public void addLocker(Locker locker) {
            lockers.add(locker);
            totalLockersUsed = lockers.size();
        }

        public void calculateMetrics() {
            double totalUsedSpace = 0;
            itemTypeChanges = 0;
            String lastItemType = null;

            for (Locker locker : lockers) {
                totalUsedSpace += (1.0 - locker.remainingSpace);

                for (String itemType : locker.itemTypes) {
                    if (lastItemType != null && !lastItemType.equals(itemType)) {
                        itemTypeChanges++;
                    }
                    lastItemType = itemType;
                }
            }

            overallUtilization = totalUsedSpace / totalLockersUsed;
        }

        @Override
        public String toString() {
            calculateMetrics();
            StringBuilder sb = new StringBuilder();
            sb.append("=== 分组优化摆放方案 ===\n");
            sb.append("使用的储物柜数量: ").append(totalLockersUsed).append("个\n");
            sb.append("平均空间利用率: ").append(String.format("%.2f", overallUtilization * 100)).append("%\n");
            sb.append("物品种类切换次数: ").append(itemTypeChanges).append("次（越少越集中）\n\n");

            for (Locker locker : lockers) {
                sb.append(locker.toString()).append("\n");
            }
            return sb.toString();
        }
    }

//    public static void main(String[] args) {
//        Scanner scanner = new Scanner(System.in);
//
//        System.out.println("请输入物品种类数量:");
//        int itemTypes = scanner.nextInt();
//        scanner.nextLine();
//
//        List<Item> items = new ArrayList<>();
//
//        for (int i = 0; i < itemTypes; i++) {
//            System.out.println("\n请输入第" + (i + 1) + "种物品的信息:");
//            System.out.print("物品名称: ");
//            String name = scanner.nextLine();
//
//            System.out.print("单种存放最大数量: ");
//            int maxCapacity = scanner.nextInt();
//
//            System.out.print("库存数量: ");
//            int stock = scanner.nextInt();
//            scanner.nextLine();
//
//            items.add(new Item(name, maxCapacity, stock));
//        }
//
//        // 使用分组优先算法
//        PackingSolution solution = packItemsWithGrouping(items);
//
//        System.out.println("\n" + solution);
//
//        scanner.close();
//    }
    public static void main(String[] args) {
        int itemTypes = 5;

        List<Item> items = new ArrayList<>();

        for (int i = 0; i < itemTypes; i++) {
            String name = i+"a";
            int maxCapacity = i*10;
            int stock = i*11;
            items.add(new Item(name, maxCapacity, stock));
        }

        // 使用分组优先算法
        PackingSolution solution = packItemsWithGrouping(items);
        for (Locker locker:solution.lockers) {
            for (String mantnr : locker.contents.keySet()){
                System.out.println(mantnr+"<===>"+locker.contents.get(mantnr));
            }
        }
        System.out.println("\n" + solution);

//        scanner.close();
    }

    /**
     * 分组优先装箱算法
     * 优先将同种物品放在一起，只有在不得已时才分开放置
     */
    public static PackingSolution packItemsWithGrouping(List<Item> items) {
        List<Item> itemsToPack = new ArrayList<>();
        for (Item item : items) {
            itemsToPack.add(new Item(item.name, item.maxCapacity, item.stock));
        }

        PackingSolution solution = new PackingSolution();
        int lockerId = 1;

        // 第一阶段：优先尝试将每种物品完整放入一个储物柜
        for (Item item : itemsToPack) {
            if (item.remaining == 0) continue;

            double totalSpaceNeeded = item.remaining * item.unitSpace;

            // 如果所有物品能放入一个储物柜
            if (totalSpaceNeeded <= 1.0) {
                boolean placedInExisting = false;

                // 寻找已有储物柜（优先选择空的）
                for (Locker locker : solution.lockers) {
                    if (locker.contents.isEmpty() && locker.canAdd(item, item.remaining)) {
                        locker.addItem(item, item.remaining);
                        placedInExisting = true;
                        break;
                    }
                }

                // 如果没有空储物柜，创建新的
                if (!placedInExisting) {
                    Locker newLocker = new Locker(lockerId++);
                    newLocker.addItem(item, item.remaining);
                    solution.addLocker(newLocker);
                }
            }
        }

        // 第二阶段：处理剩余物品（无法完整放入一个储物柜的）
        for (Item item : itemsToPack) {
            while (item.remaining > 0) {
                // 优先尝试放入已有同种物品的储物柜
                Locker bestSameTypeLocker = null;
                double bestSameTypeSpace = -1;

                for (Locker locker : solution.lockers) {
                    if (locker.containsItemType(item.name) && locker.canAdd(item, 1)) {
                        if (locker.remainingSpace > bestSameTypeSpace) {
                            bestSameTypeLocker = locker;
                            bestSameTypeSpace = locker.remainingSpace;
                        }
                    }
                }

                if (bestSameTypeLocker != null) {
                    int maxCanAdd = (int) Math.floor(bestSameTypeLocker.remainingSpace / item.unitSpace);
                    int actualAdd = Math.min(item.remaining, maxCanAdd);
                    bestSameTypeLocker.addItem(item, actualAdd);
                    continue;
                }

                // 其次尝试放入空储物柜（优先集中放置）
                Locker emptyLocker = null;
                for (Locker locker : solution.lockers) {
                    if (locker.contents.isEmpty() && locker.canAdd(item, 1)) {
                        emptyLocker = locker;
                        break;
                    }
                }

                if (emptyLocker != null) {
                    int maxCanAdd = (int) Math.floor(emptyLocker.remainingSpace / item.unitSpace);
                    int actualAdd = Math.min(item.remaining, maxCanAdd);
                    emptyLocker.addItem(item, actualAdd);
                    continue;
                }

                // 最后尝试放入任何有空间的储物柜
                Locker bestLocker = null;
                double bestRemaining = Double.MAX_VALUE;

                for (Locker locker : solution.lockers) {
                    if (locker.canAdd(item, 1) && locker.remainingSpace < bestRemaining) {
                        bestLocker = locker;
                        bestRemaining = locker.remainingSpace;
                    }
                }

                if (bestLocker != null) {
                    int maxCanAdd = (int) Math.floor(bestLocker.remainingSpace / item.unitSpace);
                    int actualAdd = Math.min(item.remaining, maxCanAdd);
                    bestLocker.addItem(item, actualAdd);
                } else {
                    // 创建新储物柜
                    Locker newLocker = new Locker(lockerId++);
                    int maxCanAdd = (int) Math.floor(1.0 / item.unitSpace);
                    int actualAdd = Math.min(item.remaining, maxCanAdd);
                    newLocker.addItem(item, actualAdd);
                    solution.addLocker(newLocker);
                }
            }
        }

        return solution;
    }

    /**
     * 按种类顺序处理算法
     * 先处理一种物品，再处理下一种
     */
    public static PackingSolution packItemsByType(List<Item> items) {
        List<Item> itemsToPack = new ArrayList<>();
        for (Item item : items) {
            itemsToPack.add(new Item(item.name, item.maxCapacity, item.stock));
        }

        PackingSolution solution = new PackingSolution();
        int lockerId = 1;

        // 按种类顺序处理
        for (Item item : itemsToPack) {
            while (item.remaining > 0) {
                // 优先使用当前正在处理该类物品的储物柜
                Locker currentTypeLocker = null;
                for (Locker locker : solution.lockers) {
                    if (locker.containsItemType(item.name) && locker.canAdd(item, 1)) {
                        currentTypeLocker = locker;
                        break;
                    }
                }

                if (currentTypeLocker != null) {
                    int maxCanAdd = (int) Math.floor(currentTypeLocker.remainingSpace / item.unitSpace);
                    int actualAdd = Math.min(item.remaining, maxCanAdd);
                    currentTypeLocker.addItem(item, actualAdd);
                    continue;
                }

                // 如果没有同种物品的储物柜，找空储物柜
                Locker emptyLocker = null;
                for (Locker locker : solution.lockers) {
                    if (locker.contents.isEmpty()) {
                        emptyLocker = locker;
                        break;
                    }
                }

                if (emptyLocker != null) {
                    int maxCanAdd = (int) Math.floor(emptyLocker.remainingSpace / item.unitSpace);
                    int actualAdd = Math.min(item.remaining, maxCanAdd);
                    emptyLocker.addItem(item, actualAdd);
                    continue;
                }

                // 创建新储物柜专门放这种物品
                Locker newLocker = new Locker(lockerId++);
                int maxCanAdd = (int) Math.floor(1.0 / item.unitSpace);
                int actualAdd = Math.min(item.remaining, maxCanAdd);
                newLocker.addItem(item, actualAdd);
                solution.addLocker(newLocker);
            }
        }

        return solution;
    }

    /**
     * 比较不同算法的效果
     */
    public static void compareAlgorithms() {
        System.out.println("=== 算法比较 ===");

        List<Item> testItems = Arrays.asList(
                new Item("X", 20, 35),
                new Item("Y", 15, 28),
                new Item("Z", 34, 45),
                new Item("T", 25, 18)
        );

        System.out.println("测试物品: " + testItems);

        // 分组优先算法
        PackingSolution groupedSolution = packItemsWithGrouping(testItems);
        System.out.println("\n分组优先算法:");
        System.out.println("储物柜数量: " + groupedSolution.totalLockersUsed);
        System.out.println("种类切换次数: " + groupedSolution.itemTypeChanges);

        // 按种类顺序算法
        PackingSolution typeOrderSolution = packItemsByType(testItems);
        System.out.println("\n按种类顺序算法:");
        System.out.println("储物柜数量: " + typeOrderSolution.totalLockersUsed);
        System.out.println("种类切换次数: " + typeOrderSolution.itemTypeChanges);

        // 原始最佳适应算法（不分组）
        PackingSolution originalSolution = packItemsOriginal(testItems);
        System.out.println("\n原始最佳适应算法:");
        System.out.println("储物柜数量: " + originalSolution.totalLockersUsed);
        System.out.println("种类切换次数: " + originalSolution.itemTypeChanges);
    }

    /**
     * 原始最佳适应算法（不分组，作为对比）
     */
    public static PackingSolution packItemsOriginal(List<Item> items) {
        List<Item> itemsToPack = new ArrayList<>();
        for (Item item : items) {
            itemsToPack.add(new Item(item.name, item.maxCapacity, item.stock));
        }

        // 按空间占用从大到小排序
        itemsToPack.sort((a, b) -> Double.compare(b.unitSpace, a.unitSpace));

        PackingSolution solution = new PackingSolution();
        int lockerId = 1;

        for (Item item : itemsToPack) {
            while (item.remaining > 0) {
                Locker bestLocker = null;
                double bestRemaining = Double.MAX_VALUE;

                for (Locker locker : solution.lockers) {
                    if (locker.canAdd(item, 1) && locker.remainingSpace < bestRemaining) {
                        bestLocker = locker;
                        bestRemaining = locker.remainingSpace;
                    }
                }

                if (bestLocker != null) {
                    int maxCanAdd = (int) Math.floor(bestLocker.remainingSpace / item.unitSpace);
                    int actualAdd = Math.min(item.remaining, maxCanAdd);
                    bestLocker.addItem(item, actualAdd);
                } else {
                    Locker newLocker = new Locker(lockerId++);
                    int maxCanAdd = (int) Math.floor(1.0 / item.unitSpace);
                    int actualAdd = Math.min(item.remaining, maxCanAdd);
                    newLocker.addItem(item, actualAdd);
                    solution.addLocker(newLocker);
                }
            }
        }

        return solution;
    }

    /**
     * 可视化展示储物柜使用情况
     */
//    public static void visualizeSolution(PackingSolution solution) {
//        System.out.println("=== 储物柜使用情况可视化 ===");
//
//        for (Locker locker : solution.lockers) {
//            System.out.println("储物柜 " + locker.id + ":");
//            for (Map.Entry<String, Integer> entry : locker.contents.entrySet()) {
//                int barLength = (int) (entry.getValue() * 50 / (1.0 / 0.05)); // 简化可视化
//                String bar = "=".repeat(barLength);
//                System.out.printf("  %s: %s %d个\n", entry.getKey(), bar, entry.getValue());
//            }
//            System.out.printf("  剩余空间: %.2f%%\n", locker.remainingSpace * 100);
//            System.out.println();
//        }
//    }

    public static void visualizeSolution(PackingSolution solution) {
        System.out.println("=== 储物柜使用情况可视化 ===");

        for (Locker locker : solution.lockers) {
            System.out.println("储物柜 " + locker.id + ":");
            for (Map.Entry<String, Integer> entry : locker.contents.entrySet()) {
                int barLength = (int) (entry.getValue() * 50 / (1.0 / 0.05));

                // 替代 String.repeat()
                StringBuilder barBuilder = new StringBuilder();
                for (int i = 0; i < barLength; i++) {
                    barBuilder.append("=");
                }
                String bar = barBuilder.toString();

                System.out.printf("  %s: %s %d个\n", entry.getKey(), bar, entry.getValue());
            }
            System.out.printf("  剩余空间: %.2f%%\n", locker.remainingSpace * 100);
            System.out.println();
        }
    }
}