package com.example.controller;

import com.alibaba.excel.EasyExcel;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.example.common.PageResult;
import com.example.common.Result;
import com.example.entity.User;
import com.example.excel.UserImportExcel;
import com.example.security.UserContext;
import com.example.service.DepartmentService;
import com.example.service.UserService;
import com.example.utils.Md5Util;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;

@RestController
@RequestMapping("/api/user")
public class UserController {

    @Autowired
    private UserService userService;

    @Autowired
    private DepartmentService departmentService;

    @GetMapping("/page")
    public Result<PageResult<User>> page(
            @RequestParam(defaultValue = "1") Long current,
            @RequestParam(defaultValue = "10") Long size,
            @RequestParam(required = false) String username,
            @RequestParam(required = false) String realName,
            @RequestParam(required = false) String deptCode) {
        String currentDeptCode = UserContext.getCurrentDeptCode();
        List<String> deptCodes = departmentService.getChildDeptCodes(currentDeptCode);
        IPage<User> page = userService.getUserPage(current, size, username, realName, deptCode, deptCodes);
        for (User record : page.getRecords()) {
            record.setDeptName(departmentService.getByDeptCode(record.getDeptCode()).getDeptName());
        }
        return Result.success(new PageResult<>(page.getTotal(), current, size, page.getRecords()));
    }

    @GetMapping("/{id}")
    public Result<User> getById(@PathVariable Long id) {
        User user = userService.getUserWithDeptById(id);
        if (user == null) {
            return Result.error("用户不存在");
        }
        String currentDeptCode = UserContext.getCurrentDeptCode();
        List<String> deptCodes = departmentService.getChildDeptCodes(currentDeptCode);
        if (!deptCodes.contains(user.getDeptCode())) {
            return Result.error("无权限查看该用户");
        }
        return Result.success(user);
    }

    @PostMapping
    public Result<Boolean> save(@RequestBody User user) {
        String currentDeptCode = UserContext.getCurrentDeptCode();
        List<String> deptCodes = departmentService.getChildDeptCodes(currentDeptCode);
        if (!deptCodes.contains(user.getDeptCode())) {
            return Result.error("无权限在该部门创建用户");
        }
        if (userService.checkUsernameExists(user.getUsername())) {
            return Result.error("用户名已存在");
        }
        if (user.getPassword() != null && !user.getPassword().isEmpty()) {
            user.setPassword(Md5Util.encrypt(user.getPassword()));
        } else {
            user.setPassword(Md5Util.encrypt("123456"));
        }
        return Result.success(userService.save(user));
    }

    @PutMapping
    public Result<Boolean> update(@RequestBody User user) {
        User existUser = userService.getById(user.getId());
        if (existUser == null) {
            return Result.error("用户不存在");
        }
        String currentDeptCode = UserContext.getCurrentDeptCode();
        List<String> deptCodes = departmentService.getChildDeptCodes(currentDeptCode);
        if (!deptCodes.contains(existUser.getDeptCode())) {
            return Result.error("无权限修改该用户");
        }
        User checkUser = userService.lambdaQuery().eq(User::getUsername, user.getUsername()).one();
        if (checkUser != null && !checkUser.getId().equals(user.getId())) {
            return Result.error("用户名已存在");
        }
        if (user.getPassword() != null && !user.getPassword().isEmpty()) {
            user.setPassword(Md5Util.encrypt(user.getPassword()));
        } else {
            user.setPassword(null);
        }
        return Result.success(userService.updateById(user));
    }

    @DeleteMapping("/{id}")
    public Result<Boolean> delete(@PathVariable Long id) {
        User user = userService.getById(id);
        if (user == null) {
            return Result.error("用户不存在");
        }
        String currentDeptCode = UserContext.getCurrentDeptCode();
        List<String> deptCodes = departmentService.getChildDeptCodes(currentDeptCode);
        if (!deptCodes.contains(user.getDeptCode())) {
            return Result.error("无权限删除该用户");
        }
        return Result.success(userService.removeById(id));
    }

    @PostMapping("/import")
    public Result<String> importUsers(@RequestParam("file") MultipartFile file) {
        if (file.isEmpty()) {
            return Result.error("上传文件不能为空");
        }
        String currentDeptCode = UserContext.getCurrentDeptCode();
        List<String> deptCodes = departmentService.getChildDeptCodes(currentDeptCode);
        String result = userService.importUsers(file, deptCodes);
        if (result.startsWith("成功")) {
            return Result.success(result);
        } else {
            return Result.error(result);
        }
    }

    @GetMapping("/template")
    public void downloadTemplate(HttpServletResponse response) throws IOException {
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        response.setCharacterEncoding("utf-8");
        String fileName = URLEncoder.encode("用户导入模版", "UTF-8").replaceAll("\\+", "%20");
        response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");

        List<UserImportExcel> templateData = new ArrayList<>();
        UserImportExcel example = new UserImportExcel();
        example.setUsername("zhangsan");
        example.setRealName("张三");
        example.setEmail("zhangsan@example.com");
        example.setPhone("13800138001");
        example.setDeptCode("1001");
        templateData.add(example);

        EasyExcel.write(response.getOutputStream(), UserImportExcel.class)
                .sheet("用户导入模版")
                .doWrite(templateData);
    }

    @PostMapping("/change-password")
    public Result<Boolean> changePassword(@RequestBody ChangePasswordRequest request) {
        Long currentUserId = UserContext.getCurrentUserId();
        if (currentUserId == null) {
            return Result.error("用户未登录");
        }
        boolean success = userService.changePassword(currentUserId, request.getOldPassword(), request.getNewPassword());
        if (success) {
            return Result.success(true);
        } else {
            return Result.error("原密码错误");
        }
    }

    static class ChangePasswordRequest {
        private String oldPassword;
        private String newPassword;

        public String getOldPassword() {
            return oldPassword;
        }

        public void setOldPassword(String oldPassword) {
            this.oldPassword = oldPassword;
        }

        public String getNewPassword() {
            return newPassword;
        }

        public void setNewPassword(String newPassword) {
            this.newPassword = newPassword;
        }
    }
}