'use client';
import { useState } from 'react';
import { useLocale, useTranslations } from 'next-intl';
import { useRouter } from 'next/navigation';
import { useSnackbar } from 'notistack';
import {
  Box,
  Dialog,
  DialogActions,
  DialogContent,
  DialogTitle,
  FormControlLabel,
  Skeleton,
  Stack,
  Switch,
  TextField,
  Typography,
} from '@mui/material';
import { AppButton, StatusChip } from '@/components';
import type { StatusKind } from '@/components';
import {
  AdminDataTable,
  AdminEmptyState,
  AdminErrorState,
  AdminPageHeader,
  AdminPager,
  type AdminTableColumn,
} from '@/components/admin';
import { useAdminCapabilities } from '@/hooks';
import { adminPartnerCenterPath } from '@/constants';
import { PARTNER_PAGE_SIZE } from '@/services/partnerCenter/constants';
import type { CenterOnboardingState, PartnerCenter, PartnerCenterInput } from '@/services/partnerCenter/types';
import { usePartnerCenters, useCreatePartnerCenter, useUpdatePartnerCenter } from '@/services/partnerCenter';

/** State → semantic chip color. verified = green, pending = amber, suspended = red, draft = neutral. */
export const CENTER_STATE_KIND: Record<CenterOnboardingState, StatusKind> = {
  verified: 'verified',
  pending_verification: 'pending',
  suspended: 'rejected',
  draft: 'neutral',
};

/**
 * Partner-center admin list (f15) — the licensed sponsoring centers (پروانه تأسیس + مسئول فنی + نماد
 * اعتماد الکترونیکی) that may be the merchant-of-record. Each row shows whether it issues invoices, its
 * sponsored-nurse count, and its onboarding state; a row opens the center detail. Admins with
 * `canManagePartners` may create a new center (inactive until verified). The full IBAN is write-then-masked —
 * it is only ever entered here, never displayed (the list carries no IBAN at all).
 */
export default function AdminPartnersPage() {
  const t = useTranslations('admin');
  const locale = useLocale();
  const router = useRouter();
  const caps = useAdminCapabilities();
  const [page, setPage] = useState(1);
  const [creating, setCreating] = useState(false);

  const centers = usePartnerCenters({}, page);
  const items = centers.data?.items ?? [];
  const pageCount = Math.max(1, Math.ceil((centers.data?.total ?? 0) / PARTNER_PAGE_SIZE));

  const columns: AdminTableColumn<PartnerCenter>[] = [
    { key: 'name', header: t('partner_col_name'), render: (c) => c.name },
    { key: 'mor', header: t('partner_col_mor'), render: (c) => t(c.isMerchantOfRecord ? 'yes' : 'no') },
    { key: 'nurses', header: t('partner_col_nurses'), render: (c) => c.sponsoredNurseCount },
    {
      key: 'state',
      header: t('partner_col_state'),
      render: (c) => <StatusChip status={CENTER_STATE_KIND[c.onboardingState]} label={t(`center_state_${c.onboardingState}`)} />,
    },
  ];

  return (
    <Box sx={{ display: 'flex', flexDirection: 'column', gap: 3 }}>
      <AdminPageHeader
        title={t('partner_title')}
        subtitle={t('partner_subtitle')}
        actions={
          caps.canManagePartners ? (
            <AppButton variant="contained" color="primary" startIcon="add" onClick={() => setCreating(true)} sx={{ m: 0 }}>
              {t('partner_create')}
            </AppButton>
          ) : undefined
        }
      />

      {centers.isLoading ? (
        <Skeleton variant="rounded" height={220} />
      ) : centers.isError ? (
        <AdminErrorState message={t('error_generic')} retryLabel={t('retry')} onRetry={() => centers.refetch()} />
      ) : items.length === 0 ? (
        <AdminEmptyState icon="partners" title={t('partner_empty')} />
      ) : (
        <AdminDataTable
          columns={columns}
          rows={items}
          getRowKey={(c) => c.id}
          ariaLabel={t('partner_title')}
          onRowClick={(c) => router.push(`/${locale}${adminPartnerCenterPath(c.id)}`)}
        />
      )}

      <AdminPager
        page={page}
        pageCount={pageCount}
        onPrev={() => setPage((p) => Math.max(1, p - 1))}
        onNext={() => setPage((p) => Math.min(pageCount, p + 1))}
        prevLabel={t('prev_page')}
        nextLabel={t('next_page')}
        indicator={t('page_indicator', { page })}
      />

      {creating ? <PartnerCenterFormDialog center={null} onClose={() => setCreating(false)} /> : null}
    </Box>
  );
}

/** The editable slice of `PartnerCenterInput`, kept as strings for controlled text/number inputs. */
interface CenterFormState {
  name: string;
  legalEntityType: string;
  mohEstablishmentPermitNo: string;
  technicalDirectorLicenseNo: string;
  enamadCode: string;
  settlementIban: string;
  isMerchantOfRecord: boolean;
  commissionRate: string;
  adminUserId: string;
}

function initialForm(center: PartnerCenter | null): CenterFormState {
  return {
    name: center?.name ?? '',
    legalEntityType: center?.legalEntityType ?? '',
    mohEstablishmentPermitNo: center?.mohEstablishmentPermitNo ?? '',
    technicalDirectorLicenseNo: center?.technicalDirectorLicenseNo ?? '',
    enamadCode: center?.enamadCode ?? '',
    // Write-then-masked: always blank on open. On edit, a blank IBAN keeps the existing masked value.
    settlementIban: '',
    isMerchantOfRecord: center?.isMerchantOfRecord ?? false,
    commissionRate: center != null ? String(center.commissionRate) : '',
    adminUserId: center?.adminUserId != null ? String(center.adminUserId) : '',
  };
}

/**
 * The create/edit dialog for a partner center — shared by the list (create, `center=null`) and the detail
 * (edit, `center` prefilled). `settlementIban` is write-then-masked: the field is always blank on open and a
 * blank submit on edit keeps the stored masked value. Validates name + permit non-empty, `commissionRate ∈
 * [0, 1)`, and (create only) an IBAN when the center is merchant-of-record.
 */
export function PartnerCenterFormDialog({ center, onClose }: { center: PartnerCenter | null; onClose: () => void }) {
  const t = useTranslations('admin');
  const { enqueueSnackbar } = useSnackbar();
  const isEdit = center != null;
  const create = useCreatePartnerCenter();
  const update = useUpdatePartnerCenter(center?.id ?? 0);
  const mutation = isEdit ? update : create;
  const [form, setForm] = useState<CenterFormState>(() => initialForm(center));

  const set = <K extends keyof CenterFormState>(key: K, value: CenterFormState[K]) =>
    setForm((f) => ({ ...f, [key]: value }));

  const commission = Number(form.commissionRate);
  const commissionValid = form.commissionRate.trim() !== '' && Number.isFinite(commission) && commission >= 0 && commission < 1;
  // On edit a blank IBAN is allowed (it keeps the stored value); on create an MoR center must supply one.
  const ibanValid = !form.isMerchantOfRecord || isEdit || form.settlementIban.trim() !== '';
  const valid =
    form.name.trim() !== '' && form.mohEstablishmentPermitNo.trim() !== '' && commissionValid && ibanValid;

  const onSave = () => {
    if (!valid) return;
    const input: PartnerCenterInput = {
      name: form.name.trim(),
      legalEntityType: form.legalEntityType.trim(),
      mohEstablishmentPermitNo: form.mohEstablishmentPermitNo.trim(),
      technicalDirectorLicenseNo: form.technicalDirectorLicenseNo.trim() || null,
      enamadCode: form.enamadCode.trim() || null,
      settlementIban: form.settlementIban.trim() || null,
      isMerchantOfRecord: form.isMerchantOfRecord,
      commissionRate: commission,
      adminUserId: form.adminUserId.trim() === '' ? null : Number(form.adminUserId),
    };
    mutation.mutate(input, {
      onSuccess: () => {
        enqueueSnackbar(t('partner_saved'), { variant: 'success' });
        onClose();
      },
    });
  };

  return (
    <Dialog open onClose={mutation.isPending ? undefined : onClose} fullWidth maxWidth="sm">
      <DialogTitle sx={{ fontWeight: 800 }}>{isEdit ? t('partner_edit') : t('partner_create')}</DialogTitle>
      <DialogContent>
        <Stack sx={{ gap: 2, mt: 1 }}>
          <TextField label={t('partner_name')} value={form.name} onChange={(e) => set('name', e.target.value)} />
          <TextField
            label={t('partner_legal_type')}
            value={form.legalEntityType}
            onChange={(e) => set('legalEntityType', e.target.value)}
          />
          <TextField
            label={t('partner_permit')}
            value={form.mohEstablishmentPermitNo}
            onChange={(e) => set('mohEstablishmentPermitNo', e.target.value)}
          />
          <TextField
            label={t('partner_tech_director_license')}
            value={form.technicalDirectorLicenseNo}
            onChange={(e) => set('technicalDirectorLicenseNo', e.target.value)}
          />
          <TextField label={t('partner_enamad')} value={form.enamadCode} onChange={(e) => set('enamadCode', e.target.value)} />
          <TextField
            label={t('partner_iban')}
            value={form.settlementIban}
            onChange={(e) => set('settlementIban', e.target.value)}
            helperText={t('partner_iban_write_hint')}
            placeholder={center?.settlementIbanMasked ?? undefined}
            slotProps={{ htmlInput: { dir: 'ltr' } }}
          />
          <Box>
            <FormControlLabel
              control={<Switch checked={form.isMerchantOfRecord} onChange={(e) => set('isMerchantOfRecord', e.target.checked)} />}
              label={t('partner_is_mor')}
            />
            <Typography variant="caption" sx={{ display: 'block', color: 'text.secondary' }}>
              {t('partner_is_mor_hint')}
            </Typography>
          </Box>
          <TextField
            type="number"
            label={t('partner_commission')}
            value={form.commissionRate}
            onChange={(e) => set('commissionRate', e.target.value)}
            slotProps={{ htmlInput: { min: 0, max: 0.999, step: 0.01 } }}
          />
          <TextField
            type="number"
            label={t('partner_admin_user')}
            value={form.adminUserId}
            onChange={(e) => set('adminUserId', e.target.value)}
            slotProps={{ htmlInput: { min: 1, step: 1 } }}
          />
        </Stack>
      </DialogContent>
      <DialogActions sx={{ px: 3, pb: 2 }}>
        <AppButton variant="text" color="inherit" onClick={onClose} disabled={mutation.isPending} sx={{ m: 0 }}>
          {t('cancel')}
        </AppButton>
        <AppButton variant="contained" color="primary" onClick={onSave} disabled={!valid || mutation.isPending} sx={{ m: 0 }}>
          {mutation.isPending ? t('saving') : t('save')}
        </AppButton>
      </DialogActions>
    </Dialog>
  );
}