import React, { useMemo, useState } from 'react';
import { useParams } from 'react-router-dom';
import { PlusIcon } from '@heroicons/react/24/outline';
import PageHeader from '../components/ui/PageHeader';
import DataTable, { type Column } from '../components/ui/DataTable';
import Modal from '../components/ui/Modal';
import ConfirmDialog from '../components/ui/ConfirmDialog';
import { ActiveBadge } from '../components/ui/StatusBadge';
import { useUrlState } from '../hooks/useUrlState';
import { usePermissions } from '../hooks/usePermissions';
import { useBranchRooms, useBranches } from '../hooks/useBranches';
import type { Room, RoomPayload } from '../types';
import SettingsLayout from '../components/layout/SettingsLayout';

/** اتاق‌های یک شعبه. ظرفیت = چند بیمار هم‌زمان، نه چند اتاق. */
export default function BranchRoomsPage() {
  const { branchUuid } = useParams<{ branchUuid: string }>();
  const { rooms, loading, create, update, remove } = useBranchRooms(branchUuid);
  const { branches } = useBranches();
  const { can } = usePermissions();
  const canUpdate = can('appointment_settings', 'update');

  const branch = branches.find((b) => b.uuid === branchUuid);

  const [urlState, setUrlState] = useUrlState({ search: '' });
  const [editing, setEditing] = useState<{ open: boolean; room: Room | null }>({ open: false, room: null });
  const [toDelete, setToDelete] = useState<Room | null>(null);

  const rows = useMemo(() => {
    const q = urlState.search.trim();
    return q === '' ? rooms : rooms.filter((r) => `${r.name} ${r.room_type ?? ''}`.includes(q));
  }, [rooms, urlState.search]);

  const columns: Column<Room>[] = [
    { key: 'name', header: 'نام اتاق', render: (r) => <span style={{ fontWeight: 600 }}>{r.name}</span> },
    { key: 'room_type', header: 'نوع', render: (r) => <span style={{ fontSize: 13 }}>{r.room_type || '—'}</span> },
    {
      key: 'capacity',
      header: 'ظرفیت هم‌زمان',
      render: (r) => <span style={{ fontSize: 13 }}>{r.capacity} نفر</span>,
    },
    { key: 'floor', header: 'طبقه', render: (r) => <span style={{ fontSize: 13 }}>{r.floor || '—'}</span> },
    { key: 'active', header: 'وضعیت', render: (r) => <ActiveBadge active={r.active} /> },
  ];

  const save = (payload: RoomPayload) => {
    const opts = { onSuccess: () => setEditing({ open: false, room: null }) };
    if (editing.room) update.mutate({ uuid: editing.room.uuid, d: payload }, opts);
    else create.mutate(payload, opts);
  };

  return (
    <SettingsLayout active="branches">
      <div className="fade-in">
        <PageHeader
          title={`اتاق‌های ${branch?.name ?? 'شعبه'}`}
          description="ظرفیت هر اتاق تعداد بیمارِ هم‌زمان است — اتاق تزریق سه‌تخته یک اتاق با ظرفیت ۳ است، نه سه اتاق."
          backTo="/admin/branches"
          breadcrumbs={[{ label: 'شعبه‌ها', to: '/admin/branches' }, { label: 'اتاق‌ها' }]}
          action={
            canUpdate ? (
              <button type="button" className="btn primary" onClick={() => setEditing({ open: true, room: null })}>
                <PlusIcon style={{ width: 16 }} /> افزودن اتاق
              </button>
            ) : undefined
          }
        />

        <DataTable
          columns={columns}
          data={rows}
          loading={loading}
          searchValue={urlState.search}
          onSearchChange={(v) => setUrlState({ search: v })}
          searchPlaceholder="جستجو در اتاق‌ها..."
          emptyMessage="هنوز اتاقی برای این شعبه ثبت نشده است"
          actions={
            canUpdate
              ? (r) => (
                  <div style={{ display: 'flex', gap: 6 }}>
                    <button type="button" className="btn secondary sm" onClick={() => setEditing({ open: true, room: r })}>
                      ویرایش
                    </button>
                    <button type="button" className="btn secondary sm" onClick={() => setToDelete(r)}>
                      حذف
                    </button>
                  </div>
                )
              : undefined
          }
        />

        <RoomModal
          open={editing.open}
          room={editing.room}
          saving={create.isPending || update.isPending}
          onClose={() => setEditing({ open: false, room: null })}
          onSave={save}
        />

        <ConfirmDialog
          open={!!toDelete}
          title="حذف اتاق"
          message={`آیا از حذف «${toDelete?.name}» مطمئن هستید؟`}
          confirmLabel="حذف"
          loading={remove.isPending}
          onConfirm={() => toDelete && remove.mutate(toDelete.uuid, { onSuccess: () => setToDelete(null) })}
          onCancel={() => setToDelete(null)}
        />
      </div>
    </SettingsLayout>
  );
}

function RoomModal({
  open, room, saving, onClose, onSave,
}: {
  open: boolean;
  room: Room | null;
  saving: boolean;
  onClose: () => void;
  onSave: (payload: RoomPayload) => void;
}) {
  const [name, setName] = useState('');
  const [roomType, setRoomType] = useState('');
  const [capacity, setCapacity] = useState('1');
  const [floor, setFloor] = useState('');
  const [active, setActive] = useState(true);

  // فرم با هر بازشدن از روی اتاقِ هدف بازنشانی می‌شود؛ key در والد باعث remount
  // نمی‌شود چون Modal همیشه mounted است.
  React.useEffect(() => {
    if (!open) return;
    setName(room?.name ?? '');
    setRoomType(room?.room_type ?? '');
    setCapacity(String(room?.capacity ?? 1));
    setFloor(room?.floor ?? '');
    setActive(room?.active ?? true);
  }, [open, room]);

  const parsedCapacity = Number(capacity);
  const invalid = name.trim() === '' || !Number.isFinite(parsedCapacity) || parsedCapacity < 1;

  return (
    <Modal open={open} onClose={onClose} title={room ? 'ویرایش اتاق' : 'افزودن اتاق'}>
      <div style={{ display: 'grid', gap: 14 }}>
        <Field label="نام اتاق">
          <input className="field" value={name} onChange={(e) => setName(e.target.value)} placeholder="اتاق تزریق" />
        </Field>
        <Field label="نوع اتاق (اختیاری)">
          <input className="field" value={roomType} onChange={(e) => setRoomType(e.target.value)} placeholder="تزریقات" />
        </Field>
        <Field label="ظرفیت هم‌زمان">
          <input
            className="field"
            type="number"
            min={1}
            value={capacity}
            onChange={(e) => setCapacity(e.target.value)}
          />
        </Field>
        <Field label="طبقه (اختیاری)">
          <input className="field" value={floor} onChange={(e) => setFloor(e.target.value)} placeholder="۲" />
        </Field>
        <label style={{ display: 'flex', alignItems: 'center', gap: 8, fontSize: 13 }}>
          <input type="checkbox" checked={active} onChange={(e) => setActive(e.target.checked)} />
          اتاق فعال است
        </label>

        <div style={{ display: 'flex', justifyContent: 'flex-end', gap: 8, marginTop: 4 }}>
          <button type="button" className="btn secondary" onClick={onClose}>انصراف</button>
          <button
            type="button"
            className="btn primary"
            disabled={saving || invalid}
            onClick={() => onSave({
              name: name.trim(),
              room_type: roomType.trim() === '' ? null : roomType.trim(),
              capacity: parsedCapacity,
              floor: floor.trim() === '' ? null : floor.trim(),
              active,
            })}
          >
            {saving ? 'در حال ذخیره...' : 'ذخیره'}
          </button>
        </div>
      </div>
    </Modal>
  );
}

function Field({ label, children }: { label: string; children: React.ReactNode }) {
  return (
    <div style={{ display: 'grid', gap: 6 }}>
      <label style={{ fontSize: 12, color: 'var(--text-2)' }}>{label}</label>
      {children}
    </div>
  );
}
