import { downloadFile, fetchBlobUrl, request } from '../lib/apiClient'
import { toDate } from '../lib/format'

/**
 * Job requisitions — backend/job/app.py `GET /jobs/fetch`.
 *
 * Distinct from api/jobPosts.js on purpose: that serves the Matching and CV-import
 * PICKERS off /job/fetch (job_board.view). This is the requisition list behind
 * jobs.view, and carries department / vacancies / requisition_status, which the
 * picker payload does not.
 */
export function list({ search, department, requisitionStatus, employmentType,
                       hiringManagerId, top, skip, activeOnly } = {}) {
  return request('/jobs/fetch', {
    params: {
      search,
      department,
      requisition_status: requisitionStatus,
      employment_type: employmentType,
      hiring_manager_id: hiringManagerId,
      top,
      skip,
      active_only: activeOnly,
    },
  })
}

/* requisition_status is the HIRING lifecycle. The row's separate `status` field is
   the Buffer publishing lifecycle — never map the two onto one badge. Fallback
   matches GET /jobs/requisition-statuses/fetch so the dropdown still works if
   that call 403s. */
export const REQUISITION_STATUSES = [
  { value: 'open', label: 'Open' },
  { value: 'on_hold', label: 'On Hold' },
  { value: 'closed', label: 'Closed' },
  { value: 'completed', label: 'Completed' },
]
export const REQ_STATUS_LABEL = Object.fromEntries(REQUISITION_STATUSES.map((s) => [s.value, s.label]))
const LABEL_TO_STATUS = Object.fromEntries(REQUISITION_STATUSES.map((s) => [s.label, s.value]))
export const JOB_STATUSES = REQUISITION_STATUSES.map((s) => s.label)

export function listRequisitionStatuses() {
  return request('/jobs/requisition-statuses/fetch')
}

/**
 * Distinct departments across all requisitions (closed included — a past
 * hiring department is a legitimate lens on a past window). The shared option
 * list for the Dashboard and Analytics department filters: both screens cache
 * it under qk.jobs.list({ scope: 'departments' }), and React Query caches on
 * the key alone, so every consumer of that key must use THIS fetcher — two
 * queryFns returning different shapes on one key overwrite each other (the
 * React error #31 failure documented in api/inbox.js).
 */
export async function fetchDepartmentOptions() {
  const res = await list({ top: 500, activeOnly: false })
  const rows = Array.isArray(res?.data) ? res.data : []
  return [...new Set(rows.map((r) => r.department).filter(Boolean))].sort()
}

function experienceLabel(min, max) {
  if (min == null && max == null) return null
  if (min != null && max != null) return `${min}–${max} years`
  return `${min ?? max}+ years`
}

function recruiterIdsFrom(row) {
  const ids = Array.isArray(row?.current_recruiter_ids)
    ? row.current_recruiter_ids.filter(Boolean).map(String)
    : []
  if (ids.length) return ids
  return row?.current_recruiter_id ? [String(row.current_recruiter_id)] : []
}

function recruiterNamesFrom(row) {
  if (Array.isArray(row?.recruiter_names) && row.recruiter_names.length) {
    return row.recruiter_names.filter(Boolean)
  }
  if (Array.isArray(row?.recruiters) && row.recruiters.length) {
    return row.recruiters.map((r) => r?.name).filter(Boolean)
  }
  return row?.recruiter_name ? [row.recruiter_name] : []
}

/** API row -> what the Jobs table and detail modal render. */
export function toJobView(row) {
  const recruiterIds = recruiterIdsFrom(row)
  const recruiterNames = recruiterNamesFrom(row)
  return {
    id: row.id,
    title: row.title,
    department: row.department,
    location: row.location,
    type: row.employment_type,
    vacancies: row.vacancies,
    platform: row.platform || null,
    status: REQ_STATUS_LABEL[row.requisition_status] ?? row.requisition_status,
    publishStatus: row.status,
    recruiter: recruiterNames.join(', ') || null,
    recruiterId: recruiterIds[0] || null,
    recruiterIds,
    recruiterNames,
    hiringManager: row.hiring_manager_name,
    hiringManagerId: row.hiring_manager_id,
    createdByName: row.created_by_name,
    applicantCount: row.applicant_count ?? 0,
    // A real Date, so the existing `sortValue: j => j.created.getTime()` keeps working.
    created: toDate(row.created_at),
    closedAt: toDate(row.closed_at),
    requisitionStatus: row.requisition_status,
    experienceMin: row.experience_min,
    experienceMax: row.experience_max,
    experience: experienceLabel(row.experience_min, row.experience_max),
    skills: row.requirements ?? [],
    optionalSkills: row.optional_skills ?? [],
    description: row.description,
    requisitionId: row.requisition_id || null,
    requisitionTitle: row.requisition_title || '',
    requisitionDepartment: row.requisition_department || '',
    requisitionLabel: row.requisition_id
      ? `${(row.requisition_title || 'Untitled').trim() || 'Untitled'} - ${(row.requisition_department || '—').trim() || '—'}`
      : null,
  }
}

/**
 * Styled .xlsx download of the requisition list — GET /jobs/export
 * (jobs.export). Same filters as list(); `status` takes the UI label.
 * downloadFile triggers the browser save from the Content-Disposition name.
 */
export function exportXlsx({ search, department, status, employmentType } = {}) {
  return downloadFile('/jobs/export', {
    params: {
      search: search || undefined,
      department: department || undefined,
      requisition_status: status ? (LABEL_TO_STATUS[status] ?? status) : undefined,
      employment_type: employmentType || undefined,
    },
  })
}

export function update(jobPostId, body) {
  return request('/jobs/update', {
    method: 'PATCH',
    params: { job_post_id: jobPostId },
    body,
  })
}

export function remove(jobPostId) {
  return request('/jobs/delete', {
    method: 'DELETE',
    params: { job_post_id: jobPostId },
  })
}

/** Attach or replace a job post's cover image — POST /job/image/upload (multipart). */
export function uploadImage(jobPostId, file) {
  const fd = new FormData()
  fd.append('job_post_id', jobPostId)
  fd.append('file', file)
  return request('/job/image/upload', { method: 'POST', body: fd })
}

/** Object URL of the cover image, or null when the post has none. Caller revokes. */
export function fetchImageUrl(jobPostId) {
  return fetchBlobUrl('/job/image/fetch', { params: { job_post_id: jobPostId } })
}

/** `status` is the Jobs UI label (Open / Closed / On Hold) or a raw requisition_status. */
export function setStatus(jobPostId, status) {
  const requisition_status = LABEL_TO_STATUS[status] ?? status
  return request('/jobs/status', {
    method: 'PATCH',
    params: { job_post_id: jobPostId },
    body: { requisition_status },
  })
}

/** Status-change audit for one requisition — GET /jobs/status-history/fetch. */
export function listStatusHistory(jobPostId) {
  return request('/jobs/status-history/fetch', { params: { job_post_id: jobPostId } })
}