package com.linghu.controller;

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.write.handler.SheetWriteHandler;
import com.alibaba.excel.write.metadata.WriteSheet;
import com.alibaba.excel.write.metadata.holder.WriteSheetHolder;
import com.alibaba.excel.write.metadata.holder.WriteWorkbookHolder;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.linghu.listener.PlatformExcelListener;
import com.linghu.listener.UserExcelListener;
import com.linghu.model.common.ResponseResult;
import com.linghu.model.entity.Platform;
import com.linghu.model.entity.Sectionalization;
import com.linghu.model.entity.User;
import com.linghu.model.excel.ExcelDataWithRow;
import com.linghu.model.excel.PlatformExcel;
import com.linghu.model.excel.UserExcel;
import com.linghu.model.vo.UserPageVO;
import com.linghu.service.SectionalizationService;
import com.linghu.service.UserService;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.apache.poi.ss.usermodel.DataValidation;
import org.apache.poi.ss.usermodel.DataValidationConstraint;
import org.apache.poi.ss.usermodel.DataValidationHelper;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.util.CellRangeAddressList;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.time.LocalDateTime;
import java.util.*;
import java.util.stream.Collectors;

@RestController
@RequestMapping("/user")
@Api(value = "账号相关接口", tags = "设置-账号管理")
public class UserController {
    @Autowired
    private UserService userService;

    /**
     * 新增用户
     */

    @PostMapping
    @ApiOperation(value = "添加")
    public ResponseResult add(@RequestBody User user) {
        List<User> list = userService.list(new LambdaQueryWrapper<User>().eq(User::getUser_email, user.getUser_email()));
        if (list != null && list.size() > 0) {
            return ResponseResult.success("该邮箱已存在");
        }
        user.setStatus("正常");
        userService.save(user);
        return ResponseResult.success();

    }


    /**
     * 修改用户
     */
    @PutMapping
    @ApiOperation(value = "修改")
    public ResponseResult edit(@RequestBody User user) {
        User user1 = userService.getById(user.getUser_id());
        if (user1 == null) {
            return ResponseResult.error("该账户不存在");
        }
        List<User> list = userService.list(new LambdaQueryWrapper<User>()
                        .ne(User::getUser_id, user.getUser_id())
                .eq(User::getUser_email, user.getUser_email()));
        if (list != null && list.size() > 0) {
            return ResponseResult.success("该邮箱已存在");
        }
        if (!user1.getUser_email().equals(user.getUser_email())||!user1.getPassword().equals(user.getPassword())) {
            user1.setStatus("正常");
        }

        userService.updateById(user);
        return ResponseResult.success();

    }

    /**
     * 删除用户
     */

    @DeleteMapping("/{user_id}")
    @ApiOperation(value = "删除")
    public ResponseResult delete(@PathVariable("user_id") Integer user_id) {
        userService.removeById(user_id);
        return ResponseResult.success();

    }
    /**
     * 分页查询
     */
    @GetMapping
    @ApiOperation(value = "分页")
    public ResponseResult<Page<UserPageVO>> page(@RequestParam(value = "pageSize", required = false, defaultValue = "10")Integer pageSize,
                                                 @RequestParam(value = "pageNum", required = false,defaultValue = "1")Integer pageNum,
                                                 @RequestParam(value = "sectionalization_id",required = false)Integer sectionalization_id,
                                                 @RequestParam(value = "status" ,required = false)String status) {
        Page<UserPageVO> page = new Page<>(pageNum, pageSize);
        return ResponseResult.success( userService.getPage(page,sectionalization_id,status));
    }

    /**
     * 下载模板
     */

    @GetMapping("/downloadTemplate")
    @ApiOperation("下载模板")
    public ResponseEntity<byte[]> downloadTemplate() throws IOException {
        // 1. 查询所有分组名称
        List<Sectionalization> sections = sectionalizationService.list(null);
        List<String> sectionNames = sections.stream()
                .map(Sectionalization::getSectionalization_name)
                .filter(Objects::nonNull)
                .collect(Collectors.toList());

        // 2. 创建Excel写出器
        ByteArrayOutputStream out = new ByteArrayOutputStream();

        // 3. 使用自定义的SheetWriteHandler来添加数据验证
        ExcelWriter excelWriter = EasyExcel.write(out, UserExcel.class)
                .registerWriteHandler(new SheetWriteHandler() {
                    @Override
                    public void afterSheetCreate(WriteWorkbookHolder writeWorkbookHolder,
                                                 WriteSheetHolder writeSheetHolder) {
                        Sheet sheet = writeSheetHolder.getSheet();

                        // 添加数据验证（下拉框）
                        DataValidationHelper helper = sheet.getDataValidationHelper();
                        CellRangeAddressList rangeList = new CellRangeAddressList(
                                1, 65535, 3, 3); // D列（第4列）

                        DataValidationConstraint constraint = helper.createExplicitListConstraint(
                                sectionNames.toArray(new String[0]));
                        DataValidation validation = helper.createValidation(constraint, rangeList);
                        sheet.addValidationData(validation);
                    }
                })
                .build();

        // 4. 写入空数据
        WriteSheet writeSheet = EasyExcel.writerSheet("账号模板").build();
        excelWriter.write(new ArrayList<>(), writeSheet);
        excelWriter.finish();

        // 5. 构建响应
        return ResponseEntity.ok()
                .header(HttpHeaders.CONTENT_DISPOSITION, "attachment;filename=user_template.xlsx")
                .contentType(MediaType.APPLICATION_OCTET_STREAM)
                .body(out.toByteArray());
    }

    /**
     * 导入文件
     */
    // 导入文件
    @Autowired
    private SectionalizationService sectionalizationService;
    @PostMapping("/importUserExcel")
    @ApiOperation("导入用户数据")
    public ResponseResult importUserExcel(@RequestParam("file") MultipartFile file) {
        try {
            // 1. 检查文件是否为空
            if (file.isEmpty()) {
                return ResponseResult.error("上传文件不能为空");
            }

            // 2. 读取数据库中已有的用户和分组，用于重复校验
            // 2.1 已存在的用户（按用户名和邮箱分组）
            List<User> userList = userService.list();
            Map<String, User> userNameMap = userList.stream()
                    .collect(Collectors.toMap(
                            User::getUser_name,
                            user -> user, // 变量名修正为user（原excel变量名不合理）
                            (oldValue, newValue) -> oldValue // 重复用户名保留旧值
                    ));
            Map<String, User> userEmailMap = userList.stream()
                    .collect(Collectors.toMap(
                            User::getUser_email,
                            user -> user,
                            (oldValue, newValue) -> oldValue // 重复邮箱保留旧值
                    ));

            // 2.2 已存在的分组（按分组名称映射）
            List<Sectionalization> sectionalizationList = sectionalizationService.list();
            Map<String, Sectionalization> sectionMap = sectionalizationList.stream()
                    .collect(Collectors.toMap(
                            Sectionalization::getSectionalization_name,
                            section -> section,
                            (oldValue, newValue) -> oldValue
                    ));

            // 3. 读取Excel数据（使用自定义监听器）
            UserExcelListener listener = new UserExcelListener();
            EasyExcel.read(file.getInputStream(), UserExcel.class, listener)
                    .sheet() // 读取第一个sheet
                    .doRead(); // 执行读取

            // 4. 校验Excel数据并转换为User对象
            List<ExcelDataWithRow<UserExcel>> excelDataList = listener.getDataList();
            List<User> insertUserList = new ArrayList<>();
            List<String> errorMessages = new ArrayList<>();
            Set<String> emailSet = new HashSet<>(); // 用于校验导入数据中的邮箱重复
            if (excelDataList.isEmpty()) {
                return ResponseResult.error("导入失败，数据不能为空");
            }
            for (ExcelDataWithRow<UserExcel> excelData : excelDataList) {
                int rowNum = excelData.getRowNumber();
                UserExcel excelRowData = excelData.getData();
                List<String> rowErrors = new ArrayList<>();

                // 4.1 校验必填字段
                if (!StringUtils.hasText(excelRowData.getUser_name())) {
                    rowErrors.add("账户名不能为空");
                } else if (userNameMap.containsKey(excelRowData.getUser_name())) {
                    rowErrors.add("账户名已存在（数据库中重复）");
                }

                if (!StringUtils.hasText(excelRowData.getUser_email())) {
                    rowErrors.add("邮箱不能为空");
                } else {
                    if (userEmailMap.containsKey(excelRowData.getUser_email())) {
                        rowErrors.add("邮箱已存在（数据库中重复）");
                    }
                    if (emailSet.contains(excelRowData.getUser_email())) {
                        rowErrors.add("邮箱重复（导入数据中重复）");
                    }
                }

                if (!StringUtils.hasText(excelRowData.getPassword())) {
                    rowErrors.add("密码不能为空");
                }

                if (!StringUtils.hasText(excelRowData.getSectionalization_name())) {
                    rowErrors.add("账户分组不能为空");
                } else if (!sectionMap.containsKey(excelRowData.getSectionalization_name())) {
                    rowErrors.add("账户分组不存在（数据库中无此分组）");
                }

                // 4.2 处理校验结果
                if (!rowErrors.isEmpty()) {
                    // 记录错误信息
                    errorMessages.add(String.format("第%d行：%s", rowNum, String.join("；", rowErrors)));
                } else {
                    // 校验通过，转换为User对象
                    User user = new User();
                    user.setUser_name(excelRowData.getUser_name());
                    user.setUser_email(excelRowData.getUser_email());
                    user.setPassword(excelRowData.getPassword()); // 实际场景建议加密存储
                    user.setSectionalization_id(sectionMap.get(excelRowData.getSectionalization_name()).getSectionalization_id());
                    user.setStatus("正常");

                    insertUserList.add(user);
                    emailSet.add(excelRowData.getUser_email()); // 记录已添加的邮箱，用于去重
                }
            }

            // 5. 处理错误或执行批量插入
            if (!errorMessages.isEmpty()) {
                // 组装错误信息
                StringBuilder errorMsg = new StringBuilder();
                errorMsg.append("导入失败，共").append(errorMessages.size()).append("条数据有误：\n");
                errorMessages.forEach(msg -> errorMsg.append(msg).append("\n"));
                return ResponseResult.error( errorMsg.toString());
            } else {
                // 批量插入数据库
                userService.saveBatch(insertUserList);
                return ResponseResult.success("导入成功，共新增" + insertUserList.size() + "条用户数据");
            }

        } catch (Exception e) {
            // 捕获异常（如文件格式错误、IO异常等）
            return ResponseResult.error("导入失败：" + e.getMessage());
        }
    }




}