package com.example;

import java.util.List;
import java.util.Map;
import java.util.Scanner;

/**
 * 湖大选课系统主应用类
 * 不依赖Spring Boot，使用普通Java类实现
 */
public class HnuCourseSystem {
    
    public static void main(String[] args) {
        // 初始化数据库
        DatabaseUtil.initDatabase();
        
        // 创建CourseAnalysis实例
        CourseAnalysis analysis = new CourseAnalysis();
        
        // 显示菜单
        try (Scanner scanner = new Scanner(System.in)) {
            int choice;
            
            do {
                System.out.println("===== 湖大选课系统 =====");
                System.out.println("1. 查看整体统计信息");
                System.out.println("2. 查看课程类型分布");
                System.out.println("3. 查看院系统计");
                System.out.println("4. 查看学分分布");
                System.out.println("5. 查看热门课程");
                System.out.println("6. 查看课程容量使用率");
                System.out.println("7. 查看按院系分组的统计");
                System.out.println("0. 退出系统");
                System.out.print("请选择操作: ");
                
                choice = scanner.nextInt();
                scanner.nextLine(); // 消费换行符
                
                switch (choice) {
                    case 1 -> {
                        // 查看整体统计信息
                        System.out.println("\n整体统计信息:");
                        Map<String, Object> overallStats = analysis.getOverallStatistics();
                        for (Map.Entry<String, Object> entry : overallStats.entrySet()) {
                            System.out.println(entry.getKey() + ": " + entry.getValue());
                        }
                    }
                    
                    case 2 -> {
                        // 查看课程类型分布
                        System.out.println("\n课程类型分布:");
                        Map<String, Integer> typeDistribution = analysis.getCourseTypeDistribution();
                        for (Map.Entry<String, Integer> entry : typeDistribution.entrySet()) {
                            System.out.println(entry.getKey() + ": " + entry.getValue());
                        }
                    }
                    
                    case 3 -> {
                        // 查看院系统计
                        System.out.println("\n院系统计:");
                        Map<String, Integer> deptDistribution = analysis.getDepartmentDistribution();
                        for (Map.Entry<String, Integer> entry : deptDistribution.entrySet()) {
                            System.out.println(entry.getKey() + ": " + entry.getValue());
                        }
                    }
                    
                    case 4 -> {
                        // 查看学分分布
                        System.out.println("\n学分分布:");
                        Map<Double, Integer> creditDistribution = analysis.getCreditDistribution();
                        for (Map.Entry<Double, Integer> entry : creditDistribution.entrySet()) {
                            System.out.println(entry.getKey() + "学分: " + entry.getValue() + "门");
                        }
                    }
                    
                    case 5 -> {
                        // 查看热门课程
                        System.out.println("\n热门课程:");
                        List<Map<String, Object>> topCourses = analysis.getTopCourses();
                        for (int i = 0; i < topCourses.size(); i++) {
                            Map<String, Object> course = topCourses.get(i);
                            System.out.println((i + 1) + ". " + course.get("courseName") + " - " + course.get("teacher"));
                            System.out.println("   院系: " + course.get("department") + ", 容量: " + course.get("capacity") + ", 已选: " + course.get("enrolled"));
                        }
                    }
                    
                    case 6 -> {
                        // 查看课程容量使用率
                        System.out.println("\n课程容量使用率:");
                        List<Map<String, Object>> usageRates = analysis.getCourseUsageRate();
                        for (int i = 0; i < Math.min(10, usageRates.size()); i++) {
                            Map<String, Object> usage = usageRates.get(i);
                            System.out.println((i + 1) + ". " + usage.get("courseName"));
                            System.out.println("   容量: " + usage.get("capacity") + ", 已选: " + usage.get("enrolled") + ", 使用率: " + String.format("%.2f%%", usage.get("usageRate")));
                        }
                    }
                    
                    case 7 -> {
                        // 查看按院系分组的统计
                        System.out.println("\n按院系分组的统计:");
                        Map<String, Map<String, Object>> deptStats = analysis.getDepartmentStatistics();
                        for (Map.Entry<String, Map<String, Object>> entry : deptStats.entrySet()) {
                            String department = entry.getKey();
                            Map<String, Object> stats = entry.getValue();
                            System.out.println("院系: " + department);
                            System.out.println("  课程数量: " + stats.get("courseCount"));
                            System.out.println("  总学分: " + stats.get("totalCredits"));
                            System.out.println("  总容量: " + stats.get("totalCapacity"));
                            System.out.println("  总已选人数: " + stats.get("totalEnrolled"));
                            System.out.println("  使用率: " + String.format("%.2f%%", stats.get("usageRate")));
                        }
                    }
                    
                    case 0 -> System.out.println("退出系统...");
                    
                    default -> System.out.println("无效选择，请重新输入");
                }
                
                if (choice != 0) {
                    System.out.println("\n按Enter键继续...");
                    scanner.nextLine();
                }
                
            } while (choice != 0);
        }
    }
}