import { useEffect, useMemo, useState } from 'react'
import { createPortal } from 'react-dom'
import { Plus, Trash2, X, Clock, Check, XCircle } from 'lucide-react'
import { useLocale } from '@meshkee/dashboard-ui'
import { ApiError } from '../lib/api'
import { formatCellForDisplay } from '../lib/cellNumber'
import {
  addWorkshopRegistration,
  formatWorkshopDate,
  formatWorkshopRegistrationName,
  listWorkshopRegistrations,
  removeWorkshopRegistration,
  updateWorkshopRegistrationStatus,
  type WorkshopRegistration,
  type WorkshopRegistrationStatus,
} from '../services/workshopService'
import type { BusinessCustomer } from '../services/customerService'
import { useToast } from '../context/ToastContext'
import { useT } from '../i18n/useT'
import { AddWorkshopRegistrationModal } from './AddWorkshopRegistrationModal'
import { Tooltip } from './Tooltip'
import modalStyles from './VariationsModal.module.css'
import styles from './WorkshopRegistrationsModal.module.css'

interface WorkshopRegistrationsModalProps {
  open: boolean
  workshopId: string
  workshopTitle: string
  onClose: () => void
  onRegistrationAdded?: () => void
  onRegistrationRemoved?: () => void
}

const ANIMATION_MS = 220

const STATUS_CONTROLS: {
  status: WorkshopRegistrationStatus
  icon: typeof Clock
  labelKey: 'workshop.registrations.status.pending' | 'workshop.registrations.status.approved' | 'workshop.registrations.status.rejected'
  className: 'statusBtnPending' | 'statusBtnApprove' | 'statusBtnReject'
}[] = [
  {
    status: 'pending',
    icon: Clock,
    labelKey: 'workshop.registrations.status.pending',
    className: 'statusBtnPending',
  },
  {
    status: 'approved',
    icon: Check,
    labelKey: 'workshop.registrations.status.approved',
    className: 'statusBtnApprove',
  },
  {
    status: 'rejected',
    icon: XCircle,
    labelKey: 'workshop.registrations.status.rejected',
    className: 'statusBtnReject',
  },
]

export function WorkshopRegistrationsModal({
  open,
  workshopId,
  workshopTitle,
  onClose,
  onRegistrationAdded,
  onRegistrationRemoved,
}: WorkshopRegistrationsModalProps) {
  const t = useT()
  const { showToast } = useToast()
  const { locale } = useLocale()
  const dateLocale = locale === 'fa' ? 'fa' : 'en'
  const [mounted, setMounted] = useState(open)
  const [closing, setClosing] = useState(false)
  const [registrations, setRegistrations] = useState<WorkshopRegistration[]>([])
  const [isLoading, setIsLoading] = useState(false)
  const [error, setError] = useState('')
  const [addError, setAddError] = useState('')
  const [addOpen, setAddOpen] = useState(false)
  const [isAdding, setIsAdding] = useState(false)
  const [updatingId, setUpdatingId] = useState<string | null>(null)
  const [removingId, setRemovingId] = useState<string | null>(null)

  const registeredUserIds = useMemo(
    () => registrations.map((registration) => registration.userId),
    [registrations],
  )

  useEffect(() => {
    if (open) {
      setMounted(true)
      setClosing(false)
    } else if (mounted) {
      setClosing(true)
      const timer = setTimeout(() => {
        setMounted(false)
        setClosing(false)
        setAddOpen(false)
        setAddError('')
      }, ANIMATION_MS)
      return () => clearTimeout(timer)
    }
  }, [open, mounted])

  useEffect(() => {
    if (!open || !workshopId) return

    const controller = new AbortController()
    void loadRegistrations(controller.signal)
    return () => controller.abort()
  }, [open, workshopId])

  async function loadRegistrations(signal?: AbortSignal) {
    setIsLoading(true)
    setError('')

    try {
      const data = await listWorkshopRegistrations(workshopId, signal)
      setRegistrations(data.items)
    } catch (err) {
      if (err instanceof DOMException && err.name === 'AbortError') return
      if (err instanceof ApiError) {
        setError(err.message)
      } else {
        setError(t('workshop.registrations.errorLoad'))
      }
    } finally {
      setIsLoading(false)
    }
  }

  async function handleAddCustomer(customer: BusinessCustomer) {
    setIsAdding(true)
    setAddError('')

    try {
      const result = await addWorkshopRegistration(workshopId, customer.id)
      setRegistrations((current) => [result.registration, ...current])
      setAddOpen(false)
      showToast(t('workshop.registrations.toast.added'), 'success')
      onRegistrationAdded?.()
    } catch (err) {
      if (err instanceof ApiError) {
        setAddError(err.message)
      } else {
        setAddError(t('workshop.registrations.errorAdd'))
      }
    } finally {
      setIsAdding(false)
    }
  }

  function openAddModal() {
    setAddError('')
    setAddOpen(true)
  }

  function closeAddModal() {
    if (isAdding) return
    setAddOpen(false)
    setAddError('')
  }

  async function handleStatusChange(
    registrationId: string,
    status: WorkshopRegistrationStatus,
  ) {
    setUpdatingId(registrationId)
    setError('')

    try {
      const result = await updateWorkshopRegistrationStatus(
        workshopId,
        registrationId,
        status,
      )
      setRegistrations((current) =>
        current.map((item) =>
          item.id === registrationId ? result.registration : item,
        ),
      )
      showToast(t('workshop.registrations.toast.statusUpdated'), 'success')
    } catch (err) {
      if (err instanceof ApiError) {
        setError(err.message)
      } else {
        setError(t('workshop.registrations.errorStatus'))
      }
    } finally {
      setUpdatingId(null)
    }
  }

  async function handleRemove(registrationId: string) {
    setRemovingId(registrationId)
    setError('')

    try {
      await removeWorkshopRegistration(workshopId, registrationId)
      setRegistrations((current) => current.filter((item) => item.id !== registrationId))
      showToast(t('workshop.registrations.toast.removed'), 'success')
      onRegistrationRemoved?.()
    } catch (err) {
      if (err instanceof ApiError) {
        setError(err.message)
      } else {
        setError(t('workshop.registrations.errorRemove'))
      }
    } finally {
      setRemovingId(null)
    }
  }

  useEffect(() => {
    if (!mounted || closing) return
    const onKey = (e: KeyboardEvent) => {
      if (e.key === 'Escape' && !addOpen) onClose()
    }
    document.addEventListener('keydown', onKey)
    return () => document.removeEventListener('keydown', onKey)
  }, [mounted, closing, addOpen, onClose])

  if (!mounted) return null

  return createPortal(
    <>
      <div
        className={`${modalStyles.overlay} ${closing ? modalStyles.overlayOut : modalStyles.overlayIn}`}
        onClick={onClose}
      >
      <div
        className={`${modalStyles.modal} ${styles.modal} ${closing ? modalStyles.modalOut : modalStyles.modalIn}`}
        onClick={(e) => e.stopPropagation()}
        role="dialog"
        aria-modal="true"
        aria-labelledby="workshop-registrations-title"
        lang={locale === 'fa' ? 'fa' : undefined}
        dir={locale === 'fa' ? 'rtl' : undefined}
      >
        <div className={modalStyles.header}>
          <div>
            <h2 id="workshop-registrations-title" className={modalStyles.title}>
              {t('workshop.registrations.title')}
            </h2>
            <p className={modalStyles.subtitle}>{workshopTitle}</p>
          </div>
          <button
            type="button"
            className={modalStyles.closeBtn}
            onClick={onClose}
            aria-label={t('common.close')}
          >
            <X size={20} />
          </button>
        </div>

        <div className={styles.content}>
          <div className={styles.body}>
            {error && (
              <p className={styles.error} role="alert">
                {error}
              </p>
            )}

            {isLoading ? (
              <p className={styles.loading}>{t('workshop.registrations.loading')}</p>
            ) : registrations.length === 0 ? (
              <p className={styles.empty}>{t('workshop.registrations.empty')}</p>
            ) : (
              <div className={styles.tableWrap}>
                <table className={styles.table}>
                  <thead>
                    <tr>
                      <th>{t('workshop.registrations.col.name')}</th>
                      <th className={styles.cellCol}>{t('workshop.registrations.col.cell')}</th>
                      <th>{t('workshop.registrations.col.date')}</th>
                      <th className={styles.statusCol}>{t('workshop.registrations.col.status')}</th>
                      <th className={styles.actionsCol} />
                    </tr>
                  </thead>
                  <tbody>
                    {registrations.map((registration) => (
                      <tr key={registration.id}>
                        <td>
                          {formatWorkshopRegistrationName(registration.user, dateLocale)}
                        </td>
                        <td className={styles.cellCol} dir="ltr">
                          {registration.user.cellNumber
                            ? formatCellForDisplay(registration.user.cellNumber)
                            : '—'}
                        </td>
                        <td>{formatWorkshopDate(registration.createdAt, dateLocale)}</td>
                        <td className={styles.statusCell}>
                          <div className={styles.statusControls}>
                            {STATUS_CONTROLS.map(({ status, icon: Icon, labelKey, className }) => {
                              const isActive = registration.status === status
                              const isBusy =
                                updatingId === registration.id || removingId === registration.id
                              return (
                                <Tooltip key={status} label={t(labelKey)}>
                                  <button
                                    type="button"
                                    className={[
                                      styles.statusBtn,
                                      styles[className],
                                      isActive ? styles.statusBtnActive : '',
                                    ]
                                      .filter(Boolean)
                                      .join(' ')}
                                    disabled={isBusy || isActive}
                                    onClick={() => handleStatusChange(registration.id, status)}
                                    aria-label={t(labelKey)}
                                    aria-pressed={isActive}
                                  >
                                    <Icon size={16} />
                                  </button>
                                </Tooltip>
                              )
                            })}
                          </div>
                        </td>
                        <td className={styles.actionsCell}>
                          <Tooltip label={t('workshop.registrations.remove')}>
                            <button
                              type="button"
                              className={modalStyles.removeRowBtn}
                              onClick={() => handleRemove(registration.id)}
                              disabled={
                                removingId === registration.id || updatingId === registration.id
                              }
                              aria-label={t('workshop.registrations.remove')}
                            >
                              <Trash2 size={16} />
                            </button>
                          </Tooltip>
                        </td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            )}
          </div>

          <div className={styles.fabDock}>
            <Tooltip label={t('workshop.registrations.add')}>
              <button
                type="button"
                className={[styles.addFab, addOpen ? styles.addFabActive : '']
                  .filter(Boolean)
                  .join(' ')}
                onClick={openAddModal}
                disabled={isAdding}
                aria-label={t('workshop.registrations.add')}
                aria-haspopup="dialog"
                aria-expanded={addOpen}
              >
                <Plus size={22} />
              </button>
            </Tooltip>
          </div>
        </div>
      </div>
      </div>

      <AddWorkshopRegistrationModal
        open={addOpen}
        excludeIds={registeredUserIds}
        isAdding={isAdding}
        error={addError}
        onClose={closeAddModal}
        onPick={handleAddCustomer}
      />
    </>,
    document.body,
  )
}