package com.ycl.jxkg.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.alibaba.fastjson2.JSONArray;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.conditions.query.LambdaQueryChainWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import com.ycl.jxkg.base.Result;
import com.ycl.jxkg.base.SystemCode;
import com.ycl.jxkg.context.WebContext;
import com.ycl.jxkg.domain.entity.ExamPaper;
import com.ycl.jxkg.domain.entity.Question;
import com.ycl.jxkg.domain.exam.PaperFixQuestionDTO;
import com.ycl.jxkg.domain.exam.PaperQuestion;
import com.ycl.jxkg.domain.exam.PaperQuestionSettingDTO;
import com.ycl.jxkg.domain.form.ExamPaperForm;
import com.ycl.jxkg.domain.other.KeyValue;
import com.ycl.jxkg.domain.question.QuestionItemObject;
import com.ycl.jxkg.domain.question.QuestionObject;
import com.ycl.jxkg.domain.question.RandomQuestionDTO;
import com.ycl.jxkg.domain.vo.admin.exam.ExamPaperEditRequestVO;
import com.ycl.jxkg.domain.vo.admin.exam.ExamPaperPageRequestVO;
import com.ycl.jxkg.domain.vo.admin.exam.ExamPaperTitleItemVO;
import com.ycl.jxkg.domain.vo.admin.exam.ExamResponseVO;
import com.ycl.jxkg.domain.vo.student.dashboard.PaperFilter;
import com.ycl.jxkg.domain.vo.student.dashboard.PaperInfo;
import com.ycl.jxkg.domain.vo.student.exam.ExamPaperPageVO;
import com.ycl.jxkg.enums.ExamPaperTypeEnum;
import com.ycl.jxkg.enums.QuestionTypeEnum;
import com.ycl.jxkg.enums.VisibilityEnum;
import com.ycl.jxkg.mapper.ExamPaperMapper;
import com.ycl.jxkg.mapper.QuestionMapper;
import com.ycl.jxkg.service.ExamPaperService;
import com.ycl.jxkg.service.QuestionService;
import com.ycl.jxkg.service.SubjectService;
import com.ycl.jxkg.service.TextContentService;
import com.ycl.jxkg.utils.DateTimeUtil;
import com.ycl.jxkg.utils.JsonUtil;
import com.ycl.jxkg.utils.PageInfoHelper;
import lombok.RequiredArgsConstructor;
import org.springframework.beans.BeanUtils;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;

import java.math.BigDecimal;
import java.util.*;
import java.util.stream.Collectors;

@Service
@RequiredArgsConstructor
public class ExamPaperServiceImpl extends ServiceImpl<ExamPaperMapper, ExamPaper> implements ExamPaperService {

    private final ExamPaperMapper examPaperMapper;
    private final QuestionMapper questionMapper;
    private final TextContentService textContentService;
    private final QuestionService questionService;
    private final SubjectService subjectService;
    private final WebContext webContext;


    @Override
    @Transactional(rollbackFor = Exception.class)
    public Result addPaper(ExamPaperForm form) {
        ExamPaper examPaper = ExamPaperForm.getEntityByForm(form, null);
        examPaper.setScore(new BigDecimal(form.getScore()));
        //随机试卷
        if (ExamPaperTypeEnum.Random.getCode().equals(form.getPaperType())) {
            //校验题目数量
            List<PaperQuestionSettingDTO> questionSetting = form.getQuestionSetting();
            //题目配置里配的试卷类型
            List<Integer> types = questionSetting.stream().map(PaperQuestionSettingDTO::getQuestionType).collect(Collectors.toList());
            Map<Integer, List<Integer>> map = questionMapper.selectBySubject(form.getSubjectId(), types)
                    .stream().collect(Collectors.groupingBy(RandomQuestionDTO::getQuestionType, Collectors.mapping(RandomQuestionDTO::getQuestionId, Collectors.toList())));

            for (PaperQuestionSettingDTO settingDTO : questionSetting) {
                Integer num = settingDTO.getNum();
                Integer questionType = settingDTO.getQuestionType();
                //需要配置的题目数量为0则跳过
                if(num ==null || num ==0 )continue;
                List<Integer> questions = map.get(questionType);
                if(CollectionUtils.isEmpty(questions) || num > questions.size())return Result.fail(SystemCode.InnerError.getCode(), QuestionTypeEnum.fromCode(questionType).getName()+"题目数量不足");
            }
            examPaper.setContent(JSON.toJSONString(form.getQuestionSetting()));
            baseMapper.insert(examPaper);
            return Result.ok();
        } else if (ExamPaperTypeEnum.Fixed.getCode().equals(form.getPaperType())) {
            //固定试卷
            examPaper.setContent(JSON.toJSONString(form.getQuestionTitleList()));
            baseMapper.insert(examPaper);
            return Result.ok();
        } else {
            //随序试卷
            Integer subjectId = form.getSubjectId();
            //题目配置
            List<PaperQuestionSettingDTO> questionSetting = form.getQuestionSetting();
            //题目配置里配的试卷类型
            List<Integer> types = questionSetting.stream().map(PaperQuestionSettingDTO::getQuestionType).collect(Collectors.toList());
            if (CollectionUtils.isEmpty(types)) {
                return Result.fail(SystemCode.InnerError.getCode(), "试卷题目类型不能为空");
            }
            Map<Integer, List<Integer>> map = questionMapper.selectBySubject(subjectId, types)
                    .stream().collect(Collectors.groupingBy(RandomQuestionDTO::getQuestionType, Collectors.mapping(RandomQuestionDTO::getQuestionId, Collectors.toList())));
            List<PaperFixQuestionDTO> questionTitleList = new ArrayList<>();
            // 遍历map
            for (Integer questionType : map.keySet()) {
                //数据库里的这个类型的题目
                List<Integer> questionIdList = map.get(questionType);
                Result result = createQuestion(questionSetting, questionTitleList, questionType, questionIdList,QuestionTypeEnum.fromCode(questionType).getCode());
                if (result != null) return result;
            }
            examPaper.setContent(JSON.toJSONString(questionTitleList));
            baseMapper.insert(examPaper);
            return Result.ok();
        }
    }
    //生成题目
    private Result createQuestion(List<PaperQuestionSettingDTO> questionSetting, List<PaperFixQuestionDTO> questionTitleList, Integer questionType, List<Integer> questionIdList , Integer questionEnumCode) {
        if (questionType.equals(questionEnumCode)) {
            //循环找到对应题目
            PaperQuestionSettingDTO settingDTO = new PaperQuestionSettingDTO();
            for (PaperQuestionSettingDTO dto : questionSetting) {
                if (dto.getQuestionType().equals(questionType)) {
                    settingDTO = dto;
                }
            }// 需要生成的题目数量
            Integer num = settingDTO.getNum();
            if(num ==null || num ==0 ){
                //题目配置此类型数量为0，跳过，不生成题目。
                return null;
            }
            if (CollectionUtils.isEmpty(questionIdList) || num > questionIdList.size()) {
                return Result.fail(SystemCode.InnerError.getCode(), QuestionTypeEnum.fromCode(questionType).getName()+"题目数量不足");
            }

            // 使用Random类生成不重复的随机索引
            Set<Integer> indexes = new HashSet<>();
            Random random = new Random();
            while (indexes.size() < num) {
                int index = random.nextInt(questionIdList.size());
                indexes.add(index);
            }
            // 根据索引获取题目
            List<Integer> questionIds = new ArrayList<>();
            for (int index : indexes) {
                questionIds.add(questionIdList.get(index));
            }
            QueryWrapper<Question> wrapper = new QueryWrapper<>();
            wrapper.in("id",questionIds);
            List<Question> questions = questionMapper.selectList(wrapper);
            List<PaperQuestion> questionList = new ArrayList<>();
            for (Question question : questions) {
                PaperQuestion paperQuestion = new PaperQuestion();
                BeanUtils.copyProperties(question,paperQuestion);
                paperQuestion.setScore(settingDTO.getScore());
                //转换
                QuestionObject questionObject = JSONObject.parseObject(question.getContent(), QuestionObject.class);
                if(questionObject != null){
                    paperQuestion.setItems(questionObject.getQuestionItemObjects());
                    paperQuestion.setAnalyze(questionObject.getAnalyze());
                    paperQuestion.setTitle(questionObject.getTitleContent());
                }
                questionList.add(paperQuestion);
            }
            PaperFixQuestionDTO dto = new PaperFixQuestionDTO();
            dto.setTitle(settingDTO.getTitle());
            dto.setQuestionType(questionType);
            dto.setQuestionList(questionList);
            questionTitleList.add(dto);
        }
        return null;
    }

    @Override
    public Result updateExamPaper(ExamPaperForm form) {
        ExamPaper examPaper = ExamPaperForm.getEntityByForm(form, null);
        examPaper.setScore(new BigDecimal(form.getScore()));
        //随机试卷
        if (ExamPaperTypeEnum.Random.getCode().equals(form.getPaperType())) {
            examPaper.setContent(JSON.toJSONString(form.getQuestionSetting()));
            baseMapper.updateById(examPaper);
            return Result.ok();
        } else if (ExamPaperTypeEnum.Fixed.getCode().equals(form.getPaperType())) {
            //固定试卷
            examPaper.setContent(JSON.toJSONString(form.getQuestionTitleList()));
            baseMapper.updateById(examPaper);
            return Result.ok();
        } else {
            //随序试卷
            examPaper.setContent(JSON.toJSONString(form.getQuestionTitleList()));
            baseMapper.updateById(examPaper);
            return Result.ok();
        }
    }

    @Override
    public PageInfo<ExamResponseVO> page(ExamPaperPageRequestVO requestVM) {
        PageInfo<ExamPaper> page = PageHelper.startPage(requestVM.getPageIndex(), requestVM.getPageSize(), "id desc").doSelectPageInfo(() ->
                examPaperMapper.page(requestVM));
        PageInfo<ExamResponseVO> pageVO = PageInfoHelper.copyMap(page, e -> {
            ExamResponseVO vo = new ExamResponseVO();
            BeanUtils.copyProperties(e, vo);
            vo.setVisibility(VisibilityEnum.valueOf(vo.getVisibility()).getCode() + "");
            vo.setCreateTime(DateTimeUtil.dateFormat(e.getCreateTime()));
            return vo;
        });
        return pageVO;
    }


//    @Override
//    public PageInfo<ExamPaper> taskExamPage(ExamPaperPageRequestVO requestVM) {
//        return PageHelper.startPage(requestVM.getPageIndex(), requestVM.getPageSize(), "id desc").doSelectPageInfo(() ->
//                examPaperMapper.taskExamPage(requestVM));
//    }

    @Override
    public PageInfo<ExamPaper> studentPage(ExamPaperPageVO requestVM) {
        return PageHelper.startPage(requestVM.getPageIndex(), requestVM.getPageSize(), "id desc").doSelectPageInfo(() ->
                examPaperMapper.studentPage(requestVM));
    }


//    @Override
//    @Transactional
//    public ExamPaper savePaperFromVM(ExamPaperEditRequestVO examPaperEditRequestVO, User user) {
//        ActionEnum actionEnum = (examPaperEditRequestVO.getId() == null) ? ActionEnum.ADD : ActionEnum.UPDATE;
//        Date now = new Date();
//        List<ExamPaperTitleItemVO> titleItemsVM = examPaperEditRequestVO.getTitleItems();
//        List<ExamPaperTitleItemObject> frameTextContentList = frameTextContentFromVM(titleItemsVM);
//        String frameTextContentStr = JsonUtil.toJsonStr(frameTextContentList);
//
//        ExamPaper examPaper = new ExamPaper();
//        BeanUtils.copyProperties(examPaperEditRequestVO, examPaper);
//        if (actionEnum == ActionEnum.ADD) {
//            TextContent frameTextContent = new TextContent();
//            frameTextContent.setContent(frameTextContentStr);
//            frameTextContent.setCreateTime(now);
//            textContentService.save(frameTextContent);
//            examPaper.setCreateTime(now);
//            examPaper.setCreateUser(user.getId());
//            examPaperFromVM(examPaperEditRequestVO, examPaper, titleItemsVM);
//            examPaperMapper.insert(examPaper);
//        } else {
//            examPaper = examPaperMapper.selectById(examPaperEditRequestVO.getId());
//          //TODO:
//            TextContent frameTextContent = textContentService.getById(examPaper.getFrameTextContentId());
//            frameTextContent.setContent(frameTextContentStr);
//            textContentService.updateById(frameTextContent);
//            examPaperFromVM(examPaperEditRequestVO, examPaper, titleItemsVM);
//            examPaperMapper.updateById(examPaper);
//        }
//        return examPaper;
//    }

    @Override
    public ExamPaperEditRequestVO examPaperToVM(Integer id) {
        ExamPaper examPaper = examPaperMapper.selectById(id);
        ExamPaperEditRequestVO vo = new ExamPaperEditRequestVO();
        BeanUtils.copyProperties(examPaper, vo);
        vo.setVisibility(VisibilityEnum.valueOf(vo.getVisibility()).getCode());
        //随机试卷
        if (ExamPaperTypeEnum.Random.getCode().equals(examPaper.getPaperType())) {
            vo.setQuestionSetting(JSONArray.parseArray(examPaper.getContent(), PaperQuestionSettingDTO.class));
        } else if (ExamPaperTypeEnum.Fixed.getCode().equals(examPaper.getPaperType())) {
            //固定试卷
            vo.setQuestionTitleList(JSONArray.parseArray(examPaper.getContent(), PaperFixQuestionDTO.class));
        } else {
            //随序试卷
            vo.setQuestionTitleList(JSONArray.parseArray(examPaper.getContent(), PaperFixQuestionDTO.class));
        }
        return vo;
    }

    @Override
    public List<PaperInfo> indexPaper(PaperFilter paperFilter) {
        return examPaperMapper.indexPaper(paperFilter);
    }


    @Override
    public Integer selectAllCount() {
        return examPaperMapper.selectAllCount();
    }

    @Override
    public List<Integer> selectMothCount() {
        Date startTime = DateTimeUtil.getMonthStartDay();
        Date endTime = DateTimeUtil.getMonthEndDay();
        List<KeyValue> mouthCount = examPaperMapper.selectCountByDate(startTime, endTime);
        List<String> mothStartToNowFormat = DateTimeUtil.MothStartToNowFormat();
        return mothStartToNowFormat.stream().map(md -> {
            KeyValue keyValue = mouthCount.stream().filter(kv -> kv.getName().equals(md)).findAny().orElse(null);
            return null == keyValue ? 0 : keyValue.getValue();
        }).collect(Collectors.toList());
    }


    private void examPaperFromVM(ExamPaperEditRequestVO examPaperEditRequestVO, ExamPaper examPaper, List<ExamPaperTitleItemVO> titleItemsVM) {
        //TODO:
//        Integer gradeLevel = subjectService.levelBySubjectId(examPaperEditRequestVO.getSubjectId());
//        Integer questionCount = titleItemsVM.stream()
//                .mapToInt(t -> t.getQuestionItems().size()).sum();
//        Integer score = titleItemsVM.stream().
//                flatMapToInt(t -> t.getQuestionItems().stream()
//                        .mapToInt(q -> ExamUtil.scoreFromVM(q.getScore()))
//                ).sum();
//        examPaper.setQuestionCount(questionCount);
//        examPaper.setScore(score);
//        examPaper.setGradeLevel(gradeLevel);
//        List<String> dateTimes = examPaperEditRequestVO.getLimitDateTime();
//        if (ExamPaperTypeEnum.Random == ExamPaperTypeEnum.fromCode(examPaper.getPaperType())) {
//            examPaper.setLimitStartTime(DateTimeUtil.parse(dateTimes.get(0), DateTimeUtil.STANDER_FORMAT));
//            examPaper.setLimitEndTime(DateTimeUtil.parse(dateTimes.get(1), DateTimeUtil.STANDER_FORMAT));
//        }
    }

//    private List<ExamPaperTitleItemObject> frameTextContentFromVM(List<ExamPaperTitleItemVO> titleItems) {
//        AtomicInteger index = new AtomicInteger(1);
//        return titleItems.stream().map(t -> {
//            ExamPaperTitleItemObject titleItem = new ExamPaperTitleItemObject();
//            BeanUtils.copyProperties(t, titleItem);
//            List<ExamPaperQuestionItemObject> questionItems = t.getQuestionItems().stream()
//                    .map(q -> {
//                        ExamPaperQuestionItemObject examPaperQuestionItemObject = new ExamPaperQuestionItemObject();
//                        BeanUtils.copyProperties(q, examPaperQuestionItemObject);
//                        examPaperQuestionItemObject.setItemOrder(index.getAndIncrement());
//                        return examPaperQuestionItemObject;
//                    })
//                    .collect(Collectors.toList());
//            titleItem.setQuestionItems(questionItems);
//            return titleItem;
//        }).collect(Collectors.toList());
//    }

    @Override
    public List<ExamPaper> myExamPaper(Integer paperType) {
        Integer userId = webContext.getCurrentUser().getId();
        List<ExamPaper> list = new LambdaQueryChainWrapper<>(baseMapper)
                .select(ExamPaper::getId, ExamPaper::getName, ExamPaper::getVisibility)
                .eq(ExamPaper::getCreateUser, userId)
                .eq(Objects.nonNull(paperType), ExamPaper::getPaperType, paperType)
                .or()
                .eq(ExamPaper::getVisibility, VisibilityEnum.Public.getName())
                .eq(Objects.nonNull(paperType), ExamPaper::getPaperType, paperType)
                .list();
        list.stream().forEach(item -> {
            if (VisibilityEnum.Public.getName().equals(item.getVisibility())) {
                item.setName(item.getName() + " (公开)");
            }
        });
        return list;
    }
}