import { unwrapApiResponse, unwrapNullableApiResponse } from '@/utils/api-response'
import { mockFlags } from '@/utils/mock-flags'
import { request } from '@/utils/request'
import type { ApiResponse, PageResult } from '@/types/common'

import type {
  BackendCollection,
  CampusRecord,
  CreateCampusRequest,
  CreateDepartmentRequest,
  DepartmentRecord,
  OrganizationResponseDto,
  UpdateCampusRequest,
  UpdateDepartmentRequest,
} from './types'

const useMockData = mockFlags.organization

function getRecords(data: BackendCollection<OrganizationResponseDto>) {
  return Array.isArray(data) ? data : (data.records ?? data.items ?? data.content ?? [])
}

export async function getCampuses(): Promise<CampusRecord[]> {
  if (useMockData) {
    return []
  }

  const firstPage = await getCampusPage(1, 200)
  const pageCount = Math.ceil(firstPage.total / firstPage.pageSize)
  if (pageCount <= 1) return firstPage.records

  const remainingPages = await Promise.all(
    Array.from({ length: pageCount - 1 }, (_, index) =>
      getCampusPage(index + 2, firstPage.pageSize),
    ),
  )
  return [firstPage, ...remainingPages].flatMap((page) => page.records)
}

async function getCampusPage(page: number, pageSize: number) {
  const response = await request.get<ApiResponse<BackendCollection<OrganizationResponseDto>>>(
    '/v1/campuses',
    { params: { page, size: pageSize } },
  )
  const data = unwrapApiResponse(response)
  const records = getRecords(data).map(mapCampus)
  return {
    records,
    total: Array.isArray(data) ? records.length : (data.total ?? records.length),
    pageSize: Array.isArray(data) ? pageSize : (data.size ?? pageSize),
  }
}

export function getDepartments(campusId?: string): Promise<DepartmentRecord[]> {
  if (useMockData) {
    return Promise.resolve([])
  }

  return getDepartmentPage(campusId).then((page) => page.records)
}

async function getDepartmentPage(
  campusId: string | undefined,
  page = 1,
  pageSize = 200,
): Promise<PageResult<DepartmentRecord>> {
  if (useMockData) {
    return { records: [], total: 0, page, pageSize }
  }

  const params: Record<string, string | number> = { page, size: pageSize }

  if (campusId) {
    params.campusId = campusId
  }

  const response = await request.get<ApiResponse<BackendCollection<OrganizationResponseDto>>>(
    '/v1/departments',
    { params },
  )
  const data = unwrapApiResponse(response)
  const records = getRecords(data).map(mapDepartment)

  return {
    records,
    total: Array.isArray(data) ? records.length : (data.total ?? records.length),
    page: Array.isArray(data) ? page : (data.page ?? page),
    pageSize: Array.isArray(data) ? pageSize : (data.size ?? pageSize),
  }
}

export async function getAllDepartments(campusId?: string): Promise<DepartmentRecord[]> {
  const firstPage = await getDepartmentPage(campusId, 1, 200)
  const pageCount = Math.ceil(firstPage.total / firstPage.pageSize)

  if (pageCount <= 1) {
    return firstPage.records
  }

  const remainingPages = await Promise.all(
    Array.from({ length: pageCount - 1 }, (_, index) =>
      getDepartmentPage(campusId, index + 2, firstPage.pageSize),
    ),
  )

  return [firstPage, ...remainingPages].flatMap((page) => page.records)
}

function mapCampus(data: OrganizationResponseDto): CampusRecord {
  return {
    id: data.id,
    code: data.code ?? data.id,
    name: data.name ?? data.campusName ?? data.id,
    institutionName: data.institutionName?.trim() || '新华院区',
    address: data.address ?? undefined,
    status: data.status ?? 'ENABLED',
    sortNo: data.sortNo ?? 0,
  }
}

function mapDepartment(data: OrganizationResponseDto): DepartmentRecord {
  return {
    id: data.id,
    campusId: data.campusId ?? '',
    parentId: data.parentId,
    code: data.code ?? data.id,
    name: data.name ?? data.departmentName ?? data.id,
    status: data.status ?? 'ENABLED',
    sortNo: data.sortNo ?? 0,
  }
}

export async function createCampus(payload: CreateCampusRequest): Promise<CampusRecord> {
  if (useMockData) {
    throw new Error('Mock 模式不执行院区写操作')
  }

  const response = await request.post<ApiResponse<OrganizationResponseDto>>('/v1/campuses', payload)
  return mapCampus(unwrapApiResponse(response))
}

export async function updateCampus(
  id: string,
  payload: UpdateCampusRequest,
): Promise<CampusRecord> {
  if (useMockData) {
    throw new Error('Mock 模式不执行院区写操作')
  }

  const response = await request.put<ApiResponse<OrganizationResponseDto>>(
    `/v1/campuses/${encodeURIComponent(id)}`,
    payload,
  )
  return mapCampus(unwrapApiResponse(response))
}

export async function deleteCampus(id: string): Promise<void> {
  if (useMockData) {
    throw new Error('Mock 模式不执行院区写操作')
  }

  const response = await request.delete<ApiResponse<null>>(`/v1/campuses/${encodeURIComponent(id)}`)
  unwrapNullableApiResponse(response)
}

export async function createDepartment(
  payload: CreateDepartmentRequest,
): Promise<DepartmentRecord> {
  if (useMockData) {
    throw new Error('Mock 模式不执行科室写操作')
  }

  const response = await request.post<ApiResponse<OrganizationResponseDto>>(
    '/v1/departments',
    payload,
  )
  return mapDepartment(unwrapApiResponse(response))
}

export async function updateDepartment(
  id: string,
  payload: UpdateDepartmentRequest,
): Promise<DepartmentRecord> {
  if (useMockData) {
    throw new Error('Mock 模式不执行科室写操作')
  }

  const response = await request.put<ApiResponse<OrganizationResponseDto>>(
    `/v1/departments/${encodeURIComponent(id)}`,
    payload,
  )
  return mapDepartment(unwrapApiResponse(response))
}

export async function deleteDepartment(id: string): Promise<void> {
  if (useMockData) {
    throw new Error('Mock 模式不执行科室写操作')
  }

  const response = await request.delete<ApiResponse<null>>(
    `/v1/departments/${encodeURIComponent(id)}`,
  )
  unwrapNullableApiResponse(response)
}