using UnityEngine;
using System.Collections.Generic;
using System.Linq;

public class QuestionManager : MonoBehaviour
{
    private List<QuestionData> allQuestions;
    private List<QuestionData> currentQuestions;
    private int currentQuestionIndex = 0;
    
    void Start()
    {
        LoadQuestions();
        ShuffleQuestions();
        GenerateWrongAnswers();
    }

    void LoadQuestions()
    {
        Debug.Log("开始加载题目");
        TextAsset jsonFile = Resources.Load<TextAsset>("multiplication_table");
        if (jsonFile != null)
        {
            Debug.Log("JSON文件加载成功：" + jsonFile.text);
            
            // 直接将 JSON 数组包装在一个对象中
            QuestionDataList questionList = JsonUtility.FromJson<QuestionDataList>("{\"questions\":" + jsonFile.text + "}");
            
            if (questionList != null && questionList.questions != null && questionList.questions.Length > 0)
            {
                allQuestions = new List<QuestionData>(questionList.questions);
                currentQuestions = new List<QuestionData>(allQuestions);
                Debug.Log($"成功加载 {currentQuestions.Count} 道题目");
                
                // 打印第一道题目以验证
                if (currentQuestions.Count > 0)
                {
                    var firstQ = currentQuestions[0];
                    Debug.Log($"第一道题目: {firstQ.multiplier1} × {firstQ.multiplier2} = {firstQ.result}");
                }
            }
            else
            {
                Debug.LogError("JSON解析失败！questionList 为空或没有题目");
            }
        }
        else
        {
            Debug.LogError("无法加载题目文件！请确保 multiplication_table.json 文件位于 Resources 文件夹中！");
        }
    }
    void GenerateWrongAnswers()
    {
        foreach (var question in currentQuestions)
        {
            // 生成一个错误答案，确保与正确答案不同
            do
            {
                // 在正确答案的±5范围内生成错误答案
                int offset = Random.Range(-5, 6);
                question.wrongAnswer = question.result + offset;
            } while (question.wrongAnswer == question.result);

            // 随机决定正确答案放在A还是B选项
            question.isAnswerA = Random.value > 0.5f;
        }
    }

    void ShuffleQuestions()
    {
        if (currentQuestions != null)
        {
            int n = currentQuestions.Count;
            while (n > 1)
            {
                n--;
                int k = Random.Range(0, n + 1);
                QuestionData temp = currentQuestions[k];
                currentQuestions[k] = currentQuestions[n];
                currentQuestions[n] = temp;
            }
        }
    }

    public QuestionData GetCurrentQuestion()
    {
        if (currentQuestions != null && currentQuestionIndex < currentQuestions.Count)
        {
            return currentQuestions[currentQuestionIndex];
        }
        return null;
    }

    public bool CheckAnswer(bool selectedA)
    {
        QuestionData currentQuestion = GetCurrentQuestion();
        if (currentQuestion != null)
        {
            return selectedA == currentQuestion.isAnswerA;
        }
        return false;
    }

    public void NextQuestion()
    {
        currentQuestionIndex++;
        if (currentQuestionIndex >= currentQuestions.Count)
        {
            // 所有题目都已完成，重新开始
            currentQuestionIndex = 0;
            ShuffleQuestions();
            GenerateWrongAnswers();
        }
    }

    public float GetProgress()
    {
        return (float)currentQuestionIndex / currentQuestions.Count;
    }
}