package cn.teammodel.test;

import cn.teammodel.model.dto.admin.teacher.IdCodePair;
import cn.teammodel.model.entity.teacher.PtTeacherInfo;
import cn.teammodel.model.vo.admin.GpTeacherVo;
import cn.teammodel.repository.PtTeacherRepository;
import com.azure.cosmos.implementation.guava25.collect.Lists;
import com.itextpdf.text.log.Logger;
import com.itextpdf.text.log.LoggerFactory;
import org.apache.commons.lang3.tuple.Pair;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.env.Environment;
import org.springframework.scheduling.annotation.Async;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.function.Function;
import java.util.stream.Collectors;

import static cn.teammodel.controller.admin.service.impl.TeacherServiceImpl.PT_TEACHER_CACHE;

@Service
public class AsyncTeacherService {
    private static final Logger log = LoggerFactory.getLogger(AsyncTeacherService.class);

    @Autowired
    private PtTeacherRepository ptTeacherRepository;

    @Transactional(rollbackFor = Exception.class)
    public void asyncSavePtTeacherInfos(List<GpTeacherVo> teachersList) {
        try {
            Map<String, PtTeacherInfo> existingTeachers = loadExistingTeachers(teachersList);

            List<PtTeacherInfo> updates = teachersList.stream()
                    .filter(t -> t.getId() != null)
                    .map(t -> convertToPtTeacherInfo(t, existingTeachers))
                    .filter(Objects::nonNull) // 过滤掉未变更的记录
                    .collect(Collectors.toList());

            if (!updates.isEmpty()) {
                ptTeacherRepository.saveAll(updates);
                updates.forEach(pt -> PT_TEACHER_CACHE.put(pt.getCode(), pt));
            }
        } catch (Exception e) {
            log.error("Failed to save teacher info asynchronously", e);
        }
    }

    private Map<String, PtTeacherInfo> loadExistingTeachers(List<GpTeacherVo> teachersList) {
        List<IdCodePair> idAndCode = teachersList.stream()
                .filter(t -> t.getId() != null)
                .map(t -> new IdCodePair(t.getId(), t.getCode() + t.getId()))
                .collect(Collectors.toList());

        List<PtTeacherInfo> existingList = ptTeacherRepository.findByIdCodePairs(idAndCode);

        return existingList.stream()
                .collect(Collectors.toMap(
                        PtTeacherInfo::getCode,
                        Function.identity()
                ));
    }

    private PtTeacherInfo convertToPtTeacherInfo(GpTeacherVo teacher, Map<String, PtTeacherInfo> existingTeachers) {

        String code = teacher.getCode() +"-"+ teacher.getId();
        PtTeacherInfo existing = existingTeachers.get(code);
        // 如果数据库无记录，直接创建新对象
        if (existing == null) {
            return createNewPtTeacherInfo(teacher, code);
        }
        // 检查字段是否有变化
        boolean isChanged = !Objects.equals(existing.getIdentity(), teacher.getIdentity());

        // 无变化则返回null，表示无需更新
        if (!isChanged) {
            return null;
        }

        PtTeacherInfo updated = new PtTeacherInfo();
        BeanUtils.copyProperties(existing, updated);
        updated.setVersion(getNextVersion(updated.getId(), updated.getCode()));
        return updated;

    }

    private Integer getNextVersion(String id,String code) {
        PtTeacherInfo existingPtTeacherInfo = ptTeacherRepository.findByIdAndCode(id,code);
        if (existingPtTeacherInfo != null) {
            return existingPtTeacherInfo.getVersion() + 1;
        }
        return 1;
    }

    private PtTeacherInfo createNewPtTeacherInfo(GpTeacherVo teacher, String code) {
        PtTeacherInfo ptTeacherInfo = new PtTeacherInfo();

        // 固定值
        ptTeacherInfo.setPk("PtTeacher");
        ptTeacherInfo.setTtl(-1);
        ptTeacherInfo.setSchool(teacher.getCode());

        // 基础信息映射
        ptTeacherInfo.setId(teacher.getId());
        ptTeacherInfo.setCode(code);
        ptTeacherInfo.setIdentity(teacher.getIdentity());

        // 版本号初始化
        ptTeacherInfo.setVersion(1);

        return ptTeacherInfo;
    }
}