import { Injectable } from "@nestjs/common"
import { CreateDepartmentDto } from "./dto/create-department.dto"
import { UpdateDepartmentDto } from "./dto/update-department.dto"
import { DepartmentRepository } from "./repositories/department.repository"
import {
  errorMessage,
  isEmpty,
  successMessage,
  validationMessage,
} from "../../utils/helpers"
import {
  failureResponse,
  successResponse,
} from "../../common/response/response"
import { code } from "../../common/response/response.code"
import { messageKey } from "../../constants/message-keys"
import { Department } from "./entities/department.entity"
import { verifyJwtToken } from "src/utils/jwt"

@Injectable()
export class DepartmentsService {
  constructor(private readonly departmentRepository: DepartmentRepository) {}

  async create(createDepartmentDto: CreateDepartmentDto, token: string) {
    const decoded = verifyJwtToken(token)
    if (!decoded) {
      return failureResponse(
        code.VALIDATION,
        validationMessage(messageKey.invalid_token),
      )
    }

    // Check if department with same name exists for the company
    const existingDepartment = await this.departmentRepository.getByParams({
      where: {
        company_id: decoded.company_id,
        name: createDepartmentDto.name,
      },
      findOne: true,
    })

    if (existingDepartment) {
      return failureResponse(
        code.VALIDATION,
        validationMessage(messageKey.already_exist, {
          ":data": "Department",
          ":field": "name",
        }),
      )
    }

    let department: any = new Department()
    department = {
      ...createDepartmentDto,
      status: createDepartmentDto.status || 1,
      company_id: decoded.company_id,
      created_by: decoded.user_id,
    }

    await this.departmentRepository.save(department)

    return successResponse(
      code.SUCCESS,
      successMessage(messageKey.data_add, { ":data": "Department" }),
    )
  }

  async findAll(query: any = {}, token: string) {
    const decoded = verifyJwtToken(token)

    if (!decoded) {
      return failureResponse(
        code.VALIDATION,
        validationMessage(messageKey.invalid_token),
      )
    }
    const {
      page = 1,
      limit = 10,
      search,
      status,
      column_name,
      order = "DESC",
    } = query

    const skip = (page - 1) * limit
    const take = parseInt(limit)

    const orderDirection = isEmpty(order) ? "DESC" : order.toUpperCase()

    // Set up dynamic ordering
    let orderBy: any = { created_at: orderDirection }

    if (!isEmpty(column_name)) {
      switch (column_name) {
        case "name":
          orderBy = { name: orderDirection }
          break
        case "created_at":
        default:
          orderBy = { created_at: orderDirection }
          break
      }
    }

    const whereConditions: any = {}
    const searchConditions: any = {}

    // Add filters
    if (decoded.company_id) {
      whereConditions.company_id = decoded.company_id
    }

    if (status !== undefined && status !== null) {
      whereConditions.status = status
    }

    // Add search functionality
    if (search) {
      searchConditions.name = search
    }

    const departments: any = await this.departmentRepository.getByParams({
      where: whereConditions,
      search: !isEmpty(searchConditions) ? searchConditions : undefined,
      relations: ["company:id,name"],
      orderBy,
      take,
      skip,
    })

    return successResponse(
      code.SUCCESS,
      successMessage(messageKey.data_retrieve, { ":data": "Departments" }),
      departments,
    )
  }

  async findOne(id: number) {
    const department: any = await this.departmentRepository.getByParams({
      where: { id },
      whereNull: ["deleted_at"],
      relations: ["company:id,name"],
      findOne: true,
    })

    if (isEmpty(department)) {
      return failureResponse(
        code.VALIDATION,
        errorMessage(messageKey.data_not_found, { ":data": "Department" }),
      )
    }

    return successResponse(
      code.SUCCESS,
      successMessage(messageKey.data_retrieve, { ":data": "Department" }),
      department,
    )
  }

  async update(
    id: number,
    updateDepartmentDto: UpdateDepartmentDto,
    token: string,
  ) {
    const decoded = verifyJwtToken(token)

    if (!decoded) {
      return failureResponse(
        code.VALIDATION,
        validationMessage(messageKey.invalid_token),
      )
    }

    const department: any = await this.departmentRepository.getByParams({
      where: { id },
      findOne: true,
    })

    if (isEmpty(department)) {
      return failureResponse(
        code.VALIDATION,
        errorMessage(messageKey.data_not_found, { ":data": "Department" }),
      )
    }

    // Check if department with same name exists for the company (excluding current record)
    if (updateDepartmentDto.name) {
      const existingDepartment = await this.departmentRepository.getByParams({
        where: {
          company_id: decoded.company_id,
          name: updateDepartmentDto.name,
        },
        whereNull: ["deleted_at"],
        whereNotIn: { id: [id] },
        findOne: true,
      })

      if (existingDepartment) {
        return failureResponse(
          code.VALIDATION,
          validationMessage(messageKey.already_exist, {
            ":data": "Department",
            ":field": "name",
          }),
        )
      }
    }

    // Update the department
    Object.assign(department, updateDepartmentDto)
    department.updated_by = decoded.user_id
    await this.departmentRepository.save(department)

    return successResponse(
      code.SUCCESS,
      successMessage(messageKey.data_update, { ":data": "Department" }),
    )
  }

  async remove(id: number, token: string) {
    const decoded = verifyJwtToken(token)

    if (!decoded) {
      return failureResponse(
        code.VALIDATION,
        validationMessage(messageKey.invalid_token),
      )
    }

    const department: any = await this.departmentRepository.getByParams({
      where: { id },
      whereNull: ["deleted_at"],
      findOne: true,
    })

    if (isEmpty(department)) {
      return failureResponse(
        code.VALIDATION,
        errorMessage(messageKey.data_not_found, { ":data": "Department" }),
      )
    }

    await this.departmentRepository.remove({ id: department.id })

    await this.departmentRepository.save({
      id: department.id,
      deleted_by: decoded.user_id,
    })

    return successResponse(
      code.SUCCESS,
      successMessage(messageKey.data_removed, { ":data": "Department" }),
    )
  }

  async activeInactive(id: number, token: string) {
    const decoded = verifyJwtToken(token)

    if (!decoded) {
      return failureResponse(
        code.VALIDATION,
        validationMessage(messageKey.invalid_token),
      )
    }

    const department: any = await this.departmentRepository.getByParams({
      where: { id, company_id: decoded.company_id },
      findOne: true,
    })

    if (isEmpty(department)) {
      return failureResponse(
        code.VALIDATION,
        errorMessage(messageKey.data_not_found, { ":data": "Department" }),
      )
    }

    department.status = department.status === 1 ? 0 : 1
    department.updated_by = decoded.user_id

    await this.departmentRepository.save(department)

    return successResponse(
      code.SUCCESS,
      successMessage(messageKey.data_update, { ":data": "Department" }),
    )
  }

  async checkDepartmentExist(name: string, companyId: number) {
    const department = await this.departmentRepository.getByParams({
      where: {
        name: name,
        company_id: companyId,
      },
      findOne: true,
    })

    return !isEmpty(department)
  }
}