package com.sinata.appointment.service;

import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.write.metadata.WriteSheet;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.sinata.appointment.config.MiniStpUtil;
import com.sinata.appointment.constants.BizErrorCode;
import com.sinata.appointment.constants.MiniUserType;
import com.sinata.appointment.dto.VisitorUserDetailVo;
import com.sinata.appointment.dto.VisitorUserExportRow;
import com.sinata.appointment.dto.VisitorUserListVo;
import com.sinata.appointment.dto.VisitorUserStatusPatchRequest;
import com.sinata.appointment.dto.VisitorUserUpdateRequest;
import com.sinata.appointment.entity.AppointmentOrder;
import com.sinata.appointment.entity.MpUser;
import com.sinata.appointment.exception.BizException;
import com.sinata.appointment.mapper.AppointmentOrderMapper;
import com.sinata.appointment.mapper.MpUserMapper;
import com.sinata.appointment.util.MobileMaskUtil;
import com.sinata.appointment.util.PhoneNormalize;
import com.sinata.appointment.util.UuidAssert;
import jakarta.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.StringUtils;

@Service
@RequiredArgsConstructor
public class VisitorUserManageApplicationService {

    private static final DateTimeFormatter EXPORT_TIME_FORMATTER =
            DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");

    private final MpUserMapper mpUserMapper;
    private final AppointmentOrderMapper appointmentOrderMapper;

    public IPage<VisitorUserListVo> page(
            long page,
            long size,
            String userName,
            String mobile,
            String companyName,
            LocalDate registerStartDate,
            LocalDate registerEndDate,
            Integer status) {
        Page<MpUser> result =
                mpUserMapper.selectPage(
                        new Page<>(page, size),
                        buildVisitorQuery(
                                userName, mobile, companyName, registerStartDate, registerEndDate, status));
        List<Long> userIds = result.getRecords().stream().map(MpUser::getId).filter(Objects::nonNull).toList();
        Map<Long, Long> bookingCountMap = loadBookingCountMap(userIds);
        return result.convert(user -> toListVo(user, bookingCountMap));
    }

    public void exportExcel(
            HttpServletResponse response,
            String userName,
            String mobile,
            String companyName,
            LocalDate registerStartDate,
            LocalDate registerEndDate,
            Integer status)
            throws IOException {
        prepareExcelResponse(response, "visitor-users.xlsx");
        long pageNo = 1L;
        long pageSize = 500L;
        boolean wroteAnyPage = false;
        try (ExcelWriter writer =
                EasyExcel.write(response.getOutputStream(), VisitorUserExportRow.class).build()) {
            WriteSheet sheet = EasyExcel.writerSheet("访客信息").build();
            while (true) {
                IPage<MpUser> page =
                        mpUserMapper.selectPage(
                                new Page<>(pageNo, pageSize),
                                buildVisitorQuery(
                                        userName,
                                        mobile,
                                        companyName,
                                        registerStartDate,
                                        registerEndDate,
                                        status));
                List<MpUser> users = page.getRecords();
                if (users == null || users.isEmpty()) {
                    break;
                }
                List<Long> userIds = users.stream().map(MpUser::getId).filter(Objects::nonNull).toList();
                Map<Long, Long> bookingCountMap = loadBookingCountMap(userIds);
                List<VisitorUserExportRow> rows =
                        users.stream().map(user -> toExportRow(user, bookingCountMap)).toList();
                writer.write(rows, sheet);
                wroteAnyPage = true;
                if (pageNo * pageSize >= page.getTotal()) {
                    break;
                }
                pageNo++;
            }
            if (!wroteAnyPage) {
                writer.write(List.of(), sheet);
            }
        }
    }

    private void prepareExcelResponse(HttpServletResponse response, String filename) {
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        response.setCharacterEncoding("UTF-8");
        response.setHeader("Content-Disposition", "attachment; filename=\"" + filename + "\"");
    }

    public VisitorUserDetailVo detail(Long id, String uuid) {
        MpUser user = loadVisitorUserWithUuid(id, uuid);
        VisitorUserDetailVo vo = new VisitorUserDetailVo();
        vo.setId(user.getId());
        vo.setUuid(user.getUuid());
        vo.setUserName(firstNonBlank(user.getNickName(), "—"));
        vo.setMobile(user.getMobile());
        vo.setGender(trimToNull(user.getGender()));
        vo.setCompanyName(trimToNull(user.getCompanyName()));
        vo.setStatus(user.getStatus() == null ? 1 : user.getStatus());
        return vo;
    }

    @Transactional(rollbackFor = Exception.class)
    public void update(Long id, VisitorUserUpdateRequest request) {
        MpUser user = loadVisitorUserWithUuid(id, request.getUuid());
        String userName = trimRequired(request.getUserName(), "用户名称不能为空");
        if (userName.length() > 30) {
            throw new BizException(BizErrorCode.AUTH_INVALID_CREDENTIALS, "用户名称不能超过30个字");
        }
        String mobile = trimRequired(request.getMobile(), "用户电话不能为空");
        if (!mobile.matches("^\\d{11}$")) {
            throw new BizException(BizErrorCode.AUTH_INVALID_CREDENTIALS, "用户电话须为11位数字");
        }
        assertMobileUnique(mobile, user.getId());
        String gender = trimToNull(request.getGender());
        if (StringUtils.hasText(gender) && !"男".equals(gender) && !"女".equals(gender)) {
            throw new BizException(BizErrorCode.AUTH_INVALID_CREDENTIALS, "性别仅支持男/女");
        }
        String companyName = trimToNull(request.getCompanyName());

        user.setNickName(userName);
        user.setMobile(mobile);
        user.setGender(gender);
        user.setCompanyName(companyName);
        mpUserMapper.updateById(user);
    }

    @Transactional(rollbackFor = Exception.class)
    public void patchStatus(Long id, VisitorUserStatusPatchRequest request) {
        MpUser user = loadVisitorUserWithUuid(id, request.getUuid());
        Integer status = request.getStatus();
        if (status == null || (status != 0 && status != 1)) {
            throw new BizException(BizErrorCode.AUTH_INVALID_CREDENTIALS, "状态无效");
        }
        user.setStatus(status);
        mpUserMapper.updateById(user);
        if (status == 0) {
            kickMiniUserOffline(user.getId());
        }
    }

    @Transactional(rollbackFor = Exception.class)
    public void delete(Long id, String uuid) {
        MpUser user = loadVisitorUserWithUuid(id, uuid);
        int affected = mpUserMapper.deleteById(user.getId());
        if (affected <= 0) {
            throw new BizException(BizErrorCode.RESOURCE_VERIFY_FAILED, "删除失败，请刷新后重试");
        }
        kickMiniUserOffline(user.getId());
    }

    private Map<Long, Long> loadBookingCountMap(List<Long> userIds) {
        Map<Long, Long> result = new HashMap<>();
        if (userIds == null || userIds.isEmpty()) {
            return result;
        }
        List<AppointmentOrder> rows =
                appointmentOrderMapper.selectList(
                        new LambdaQueryWrapper<AppointmentOrder>()
                                .eq(AppointmentOrder::getDelFlag, 0)
                                .in(AppointmentOrder::getSubmitterId, userIds));
        for (AppointmentOrder row : rows) {
            if (row.getSubmitterId() != null) {
                result.merge(row.getSubmitterId(), 1L, Long::sum);
            }
        }
        return result;
    }

    private VisitorUserListVo toListVo(MpUser user, Map<Long, Long> bookingCountMap) {
        VisitorUserListVo vo = new VisitorUserListVo();
        vo.setId(user.getId());
        vo.setUuid(user.getUuid());
        vo.setUserName(firstNonBlank(user.getNickName(), "—"));
        vo.setGender(defaultText(trimToNull(user.getGender())));
        vo.setMobileMasked(MobileMaskUtil.mask(user.getMobile()));
        vo.setCompanyName(defaultText(trimToNull(user.getCompanyName())));
        vo.setBookingCount(bookingCountMap.getOrDefault(user.getId(), 0L));
        vo.setStatus(user.getStatus() == null ? 1 : user.getStatus());
        vo.setCreateTime(user.getCreateTime());
        return vo;
    }

    private VisitorUserExportRow toExportRow(MpUser user, Map<Long, Long> bookingCountMap) {
        VisitorUserExportRow row = new VisitorUserExportRow();
        row.setUserName(firstNonBlank(user.getNickName(), "—"));
        row.setGender(defaultText(trimToNull(user.getGender())));
        row.setMobile(defaultText(trimToNull(user.getMobile())));
        row.setCompanyName(defaultText(trimToNull(user.getCompanyName())));
        row.setBookingCount(bookingCountMap.getOrDefault(user.getId(), 0L));
        row.setStatusText(user.getStatus() != null && user.getStatus() == 0 ? "禁用" : "启用");
        row.setCreateTime(formatDateTime(user.getCreateTime()));
        return row;
    }

    private LambdaQueryWrapper<MpUser> buildVisitorQuery(
            String userName,
            String mobile,
            String companyName,
            LocalDate registerStartDate,
            LocalDate registerEndDate,
            Integer status) {
        LambdaQueryWrapper<MpUser> query = new LambdaQueryWrapper<>();
        query.eq(MpUser::getDelFlag, 0).eq(MpUser::getUserType, MiniUserType.VISITOR);
        query.like(StringUtils.hasText(userName), MpUser::getNickName, trim(userName));
        query.like(StringUtils.hasText(mobile), MpUser::getMobile, trim(mobile));
        query.like(StringUtils.hasText(companyName), MpUser::getCompanyName, trim(companyName));
        query.eq(status != null, MpUser::getStatus, status);
        query.ge(registerStartDate != null, MpUser::getCreateTime, atStart(registerStartDate));
        query.lt(registerEndDate != null, MpUser::getCreateTime, atNextDay(registerEndDate));
        query.orderByDesc(MpUser::getCreateTime).orderByDesc(MpUser::getId);
        return query;
    }

    private void assertMobileUnique(String mobileRaw, Long excludeUserId) {
        String normalized = PhoneNormalize.mainland(mobileRaw);
        List<MpUser> rows =
                mpUserMapper.selectList(
                        new LambdaQueryWrapper<MpUser>()
                                .eq(MpUser::getDelFlag, 0)
                                .isNotNull(MpUser::getMobile));
        for (MpUser row : rows) {
            if (excludeUserId != null && excludeUserId.equals(row.getId())) {
                continue;
            }
            if (normalized.equals(PhoneNormalize.mainland(row.getMobile()))) {
                throw new BizException(BizErrorCode.MP_STAFF_MOBILE_EXISTS, "手机号已存在");
            }
        }
    }

    private MpUser loadVisitorUserWithUuid(Long id, String uuid) {
        MpUser user = mpUserMapper.selectById(id);
        if (user == null || (user.getDelFlag() != null && user.getDelFlag() == 1)) {
            throw new BizException(BizErrorCode.RESOURCE_VERIFY_FAILED, "资源不存在或无权访问");
        }
        if (!MiniUserType.VISITOR.equals(user.getUserType())) {
            throw new BizException(BizErrorCode.RESOURCE_VERIFY_FAILED, "资源不存在或无权访问");
        }
        UuidAssert.match(user, uuid);
        return user;
    }

    private static void kickMiniUserOffline(Long mpUserId) {
        try {
            MiniStpUtil.kickout(mpUserId);
        } catch (Exception ignored) {
        }
    }

    private static LocalDateTime atStart(LocalDate date) {
        return date == null ? null : date.atStartOfDay();
    }

    private static LocalDateTime atNextDay(LocalDate date) {
        return date == null ? null : date.plusDays(1).atStartOfDay();
    }

    private static String trim(String value) {
        return value == null ? null : value.trim();
    }

    private static String trimToNull(String value) {
        String trimmed = trim(value);
        return StringUtils.hasText(trimmed) ? trimmed : null;
    }

    private static String trimRequired(String value, String message) {
        String trimmed = trimToNull(value);
        if (!StringUtils.hasText(trimmed)) {
            throw new BizException(BizErrorCode.AUTH_INVALID_CREDENTIALS, message);
        }
        return trimmed;
    }

    private static String defaultText(String value) {
        return StringUtils.hasText(value) ? value : "—";
    }

    private static String formatDateTime(LocalDateTime value) {
        return value == null ? "—" : EXPORT_TIME_FORMATTER.format(value);
    }

    @SafeVarargs
    private static String firstNonBlank(String... values) {
        if (values == null) {
            return null;
        }
        for (String value : values) {
            if (StringUtils.hasText(value)) {
                return value.trim();
            }
        }
        return null;
    }
}