package com.ruoyi.system.service.impl;

import com.ruoyi.common.core.domain.AjaxResult;
import com.ruoyi.common.utils.DateUtils;
import com.ruoyi.common.utils.SecurityUtils;
import com.ruoyi.system.domain.SysTaskAssignee;
import com.ruoyi.system.domain.vo.TaskCreateVO;
import com.ruoyi.system.mapper.SysTaskAssigneeMapper;
import com.ruoyi.system.service.ISysTaskAssigneeService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

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

/**
 * 任务执行人服务实现类
 * 
 * @author ruoyi
 */
@Slf4j
@Service
public class SysTaskAssigneeServiceImpl implements ISysTaskAssigneeService {

    @Autowired
    private SysTaskAssigneeMapper sysTaskAssigneeMapper;

    @Autowired
    private ApplicationEventPublisher eventPublisher;

    @Override
    @Transactional
    public void saveTaskAssignees(Long taskId, List<TaskCreateVO.AssigneeInfo> assignees, String userName) {
        if (assignees == null || assignees.isEmpty()) {
            return;
        }
        
        List<SysTaskAssignee> taskAssignees = new ArrayList<>();
        Date now = DateUtils.getNowDate();
        
        for (int i = 0; i < assignees.size(); i++) {
            TaskCreateVO.AssigneeInfo assigneeInfo = assignees.get(i);
            
            SysTaskAssignee taskAssignee = new SysTaskAssignee();
            taskAssignee.setTaskId(taskId);
            taskAssignee.setUserId(assigneeInfo.getUserId());
            taskAssignee.setUserName(assigneeInfo.getUserName());
            taskAssignee.setUserType(assigneeInfo.getUserType());
            // 第一个执行人员为主要执行人
            taskAssignee.setIsPrimary(i == 0 ? "1" : "0");
            taskAssignee.setSortOrder(i);
            taskAssignee.setCreateTime(now);
            taskAssignee.setCreateBy(userName);
            taskAssignee.setUpdateTime(now);
            taskAssignee.setUpdateBy(userName);
            
            taskAssignees.add(taskAssignee);
        }
        
        // 批量保存
        if (!taskAssignees.isEmpty()) {
            sysTaskAssigneeMapper.batchInsertSysTaskAssignee(taskAssignees);

        }
    }

    @Override
    @Transactional
    public boolean updateTaskAssignees(Long taskId, List<TaskCreateVO.AssigneeInfo> newAssignees, String userName) {
        if (newAssignees == null) {
            return false;
        }
        try {
            List<Long> newAssigneeIds = newAssignees.stream().map(TaskCreateVO.AssigneeInfo::getUserId).collect(Collectors.toList());
            // 查询现有的执行人员
            List<SysTaskAssignee> existingAssignees = sysTaskAssigneeMapper.selectSysTaskAssigneeByTaskId(taskId);

            List<Long> existingAssigneeIds = existingAssignees.stream().map(SysTaskAssignee::getUserId).collect(Collectors.toList());
            // 找出需要删除的执行人（在数据库中存在但在新列表中不存在）
            List<Long> assigneesToDelete = existingAssignees.stream().map(SysTaskAssignee::getUserId)
                    .filter(id -> !newAssigneeIds.contains(id))
                    .collect(Collectors.toList());

            // 找出需要添加的执行人（在新列表中存在但在数据库中不存在）
            List<TaskCreateVO.AssigneeInfo> assigneesToAdd = newAssignees.stream()
                    .filter(assignee -> !existingAssigneeIds.contains(assignee.getUserId()))
                    .collect(Collectors.toList());


            boolean hasChanges = !assigneesToDelete.isEmpty() || !assigneesToAdd.isEmpty();

            // 只有执行人员发生变化时才更新
            if (hasChanges) {
                // 删除不需要的执行人员关联
                if (!assigneesToDelete.isEmpty()) {
                    for (Long userId : assigneesToDelete) {
                        sysTaskAssigneeMapper.deleteByTaskIdAndUserId(taskId, userId);
                    }
                }

                // 添加新的执行人员关联
                if (!assigneesToAdd.isEmpty()) {
                    // 为新增的执行人设置排序和主要执行人标志
                    Date now = DateUtils.getNowDate();
                    List<SysTaskAssignee> newTaskAssignees = new ArrayList<>();

                    for (int i = 0; i < assigneesToAdd.size(); i++) {
                        TaskCreateVO.AssigneeInfo assigneeInfo = assigneesToAdd.get(i);

                        SysTaskAssignee taskAssignee = new SysTaskAssignee();
                        taskAssignee.setTaskId(taskId);
                        taskAssignee.setUserId(assigneeInfo.getUserId());
                        taskAssignee.setUserName(assigneeInfo.getUserName());
                        taskAssignee.setUserType(assigneeInfo.getUserType());
                        // 注意：这里我们不知道最终的排序，所以暂时设置为一个较大的值
                        // 在后续重新排序时会修正
                        taskAssignee.setIsPrimary("0"); // 默认不是主要执行人
                        taskAssignee.setSortOrder(999 + i); // 临时排序值
                        taskAssignee.setCreateTime(now);
                        taskAssignee.setCreateBy(userName);
                        taskAssignee.setUpdateTime(now);
                        taskAssignee.setUpdateBy(userName);

                        newTaskAssignees.add(taskAssignee);
                    }

                    // 批量保存新增的执行人
                    if (!newTaskAssignees.isEmpty()) {
                        sysTaskAssigneeMapper.batchInsertSysTaskAssignee(newTaskAssignees);
                    }
                }

                // 重新查询所有执行人并设置正确的排序和主要执行人标志
                List<SysTaskAssignee> allAssignees = sysTaskAssigneeMapper.selectSysTaskAssigneeByTaskId(taskId);
                Map<Long, SysTaskAssignee> allAssigneeMap = allAssignees.stream()
                        .collect(Collectors.toMap(SysTaskAssignee::getUserId, a -> a));


                // 更新所有执行人的排序和主要执行人标志
                Date now = DateUtils.getNowDate();
                for (int i = 0; i < newAssignees.size(); i++) {
                    TaskCreateVO.AssigneeInfo assigneeInfo = newAssignees.get(i);
                    SysTaskAssignee taskAssignee = allAssigneeMap.get(assigneeInfo.getUserId());

                    if (taskAssignee != null) {
                        // 保持原有的状态信息（如就绪状态），只更新基本信息
                        taskAssignee.setUserName(assigneeInfo.getUserName());
                        taskAssignee.setUserType(assigneeInfo.getUserType());
                        taskAssignee.setIsPrimary(i == 0 ? "1" : "0"); // 第一个为主要执行人
                        taskAssignee.setSortOrder(i);
                        taskAssignee.setUpdateTime(now);
                        taskAssignee.setUpdateBy(userName);

                        sysTaskAssigneeMapper.updateSysTaskAssignee(taskAssignee);
                    }
                }

                return true;
            }
        }catch (Exception e){
            log.error("报错了，保存到执行人员分配,taskId:{}",taskId,e);
            throw e;
        }
        return false;
    }

    @Override
    public List<SysTaskAssignee> getAssigneesByTaskId(Long taskId) {
        return sysTaskAssigneeMapper.selectSysTaskAssigneeByTaskId(taskId);
    }

    @Override
    @Transactional
    public int deleteAssigneesByTaskId(Long taskId) {
        return sysTaskAssigneeMapper.deleteSysTaskAssigneeByTaskId(taskId);
    }

    @Override
    @Transactional
    public AjaxResult setAssigneeReady(Long taskId, Long userId) {
        // 1. 查询执行人关联信息
        List<SysTaskAssignee> assignees = sysTaskAssigneeMapper.selectSysTaskAssigneeByTaskId(taskId);
        SysTaskAssignee targetAssignee = assignees.stream()
            .filter(a -> a.getUserId().equals(userId))
            .findFirst()
            .orElse(null);
        
        if (targetAssignee == null) {
            return AjaxResult.error("您不是该任务的执行人");
        }
        
        // 2. 更新就绪状态
        targetAssignee.setIsReady("1");
        targetAssignee.setReadyTime(new Date());
        targetAssignee.setUpdateBy(SecurityUtils.getUsername());
        targetAssignee.setUpdateTime(new Date());
        
        sysTaskAssigneeMapper.updateSysTaskAssignee(targetAssignee);
        
        // 3. 检查是否所有执行人都已就绪
        boolean allReady = assignees.stream()
            .allMatch(a -> a.getUserId().equals(userId) || "1".equals(a.getIsReady()));
        
        Map<String, Object> result = new HashMap<>();
        result.put("allReady", allReady);
        result.put("message", "就绪成功");
        
        return AjaxResult.success(result);
    }

    @Override
    @Transactional
    public AjaxResult cancelAssigneeReady(Long taskId, Long userId) {
        // 查询执行人关联信息
        List<SysTaskAssignee> assignees = sysTaskAssigneeMapper.selectSysTaskAssigneeByTaskId(taskId);
        SysTaskAssignee targetAssignee = assignees.stream()
            .filter(a -> a.getUserId().equals(userId))
            .findFirst()
            .orElse(null);
        
        if (targetAssignee == null) {
            return AjaxResult.error("您不是该任务的执行人");
        }
        
        // 更新就绪状态
        targetAssignee.setIsReady("0");
        targetAssignee.setReadyTime(null);
        targetAssignee.setUpdateBy(SecurityUtils.getUsername());
        targetAssignee.setUpdateTime(new Date());
        
        sysTaskAssigneeMapper.updateSysTaskAssignee(targetAssignee);
        
        return AjaxResult.success("已取消就绪");
    }

    @Override
    public List<Long> getAssigneeIds(Long taskId) {
        List<SysTaskAssignee> assignees = sysTaskAssigneeMapper.selectSysTaskAssigneeByTaskId(taskId);
        if (assignees == null || assignees.isEmpty()) {
            return Collections.emptyList();
        }
        return assignees.stream()
            .map(SysTaskAssignee::getUserId)
            .collect(Collectors.toList());
    }

    @Override
    public List<String> getAssigneeNames(Long taskId) {
        List<SysTaskAssignee> assignees = sysTaskAssigneeMapper.selectSysTaskAssigneeByTaskId(taskId);
        if (assignees == null || assignees.isEmpty()) {
            return Collections.emptyList();
        }
        return assignees.stream()
            .map(SysTaskAssignee::getUserName)
            .collect(Collectors.toList());
    }
}