import React, { useState } from 'react';
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
import { PencilIcon, EyeIcon, EyeSlashIcon, PlusIcon, UserGroupIcon } from '@heroicons/react/24/outline';
import { useForm } from 'react-hook-form';
import { zodResolver } from '@hookform/resolvers/zod';
import { z } from 'zod';
import { toast } from 'sonner';
import { api } from '../lib/api';
import type { ApiResponse } from '../lib/api';
import type { ClinicStaff } from '../types';
import { formatDate } from '../lib/utils';
import DataTable, { type Column } from '../components/ui/DataTable';
import Modal from '../components/ui/Modal';
import ConfirmDialog from '../components/ui/ConfirmDialog';
import PageHeader from '../components/ui/PageHeader';
import SettingsLayout from '../components/layout/SettingsLayout';
import { ActiveBadge } from '../components/ui/StatusBadge';
import { numericField } from '../lib/forms';

const schema = z.object({
  full_name: z.string().min(2, 'نام حداقل ۲ کاراکتر باید باشد'),
  phone: z.string().optional(),
  job_title: z.string().optional(),
  address: z.string().optional(),
  national_code: z.string().optional(),
});
type StaffFormData = z.infer<typeof schema>;

const EMPTY: ClinicStaff[] = [];

export default function StaffPage() {
  const qc = useQueryClient();
  const [createOpen, setCreateOpen] = useState(false);
  const [editTarget, setEditTarget] = useState<ClinicStaff | null>(null);
  const [toggleTarget, setToggleTarget] = useState<ClinicStaff | null>(null);

  const { data, isLoading } = useQuery<ApiResponse<ClinicStaff[]>>({
    queryKey: ['staff'],
    queryFn: () => api.get('/api/v1/staff'),
  });

  const staff = data?.data ?? EMPTY;
  const total    = staff.length;
  const active   = staff.filter((s) => s.active).length;
  const inactive = total - active;

  const createForm = useForm<StaffFormData>({ resolver: zodResolver(schema) });
  const editForm   = useForm<StaffFormData>({ resolver: zodResolver(schema) });

  const createMutation = useMutation({
    mutationFn: (body: StaffFormData) => api.post('/api/v1/staff', body),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: ['staff'] });
      setCreateOpen(false);
      createForm.reset();
      toast.success('پرسنل ایجاد شد');
    },
    onError: (err: any) => toast.error(err.message),
  });

  const editMutation = useMutation({
    mutationFn: ({ uuid, body }: { uuid: string; body: StaffFormData }) =>
      api.patch(`/api/v1/staff/${uuid}`, body),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: ['staff'] });
      setEditTarget(null);
      toast.success('اطلاعات پرسنل ویرایش شد');
    },
    onError: (err: any) => toast.error(err.message),
  });

  const toggleMutation = useMutation({
    mutationFn: (uuid: string) => api.patch(`/api/v1/staff/${uuid}/toggle`, {}),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: ['staff'] });
      setToggleTarget(null);
      toast.success('وضعیت پرسنل تغییر کرد');
    },
    onError: (err: any) => toast.error(err.message),
  });

  const openEdit = (s: ClinicStaff) => {
    editForm.reset({
      full_name: s.full_name,
      phone: s.phone ?? '',
      job_title: s.job_title ?? '',
      address: s.address ?? '',
      national_code: s.national_code ?? '',
    });
    setEditTarget(s);
  };

  const columns: Column<ClinicStaff>[] = [
    {
      key: 'full_name',
      header: 'پرسنل',
      render: (s) => (
        <div>
          <div style={{ fontWeight: 600, fontSize: 14 }}>{s.full_name}</div>
          {s.job_title && (
            <div style={{ fontSize: 12, color: 'var(--text-3)', marginTop: 2 }}>{s.job_title}</div>
          )}
        </div>
      ),
    },
    {
      key: 'phone',
      header: 'تلفن',
      render: (s) => (
        <span style={{ fontSize: 13, direction: 'ltr', display: 'inline-block' }}>
          {s.phone ?? '—'}
        </span>
      ),
    },
    {
      key: 'national_code',
      header: 'کد ملی',
      render: (s) => (
        <span style={{ fontSize: 13, direction: 'ltr', display: 'inline-block' }}>
          {s.national_code ?? '—'}
        </span>
      ),
    },
    {
      key: 'active',
      header: 'وضعیت',
      render: (s) => <ActiveBadge active={s.active} />,
    },
    {
      key: 'created_at',
      header: 'تاریخ ثبت',
      render: (s) => (
        <span style={{ fontSize: 13, color: 'var(--text-3)' }}>{formatDate(s.created_at)}</span>
      ),
    },
    {
      key: 'uuid',
      header: 'عملیات',
      render: (s) => (
        <div style={{ display: 'flex', gap: 6 }}>
          <button className="btn sm" onClick={() => openEdit(s)} title="ویرایش">
            <PencilIcon style={{ width: 15 }} />
          </button>
          <button
            className="btn sm"
            onClick={() => setToggleTarget(s)}
            title={s.active ? 'غیرفعال‌سازی' : 'فعال‌سازی'}
          >
            {s.active
              ? <EyeSlashIcon style={{ width: 15 }} />
              : <EyeIcon style={{ width: 15 }} />
            }
          </button>
        </div>
      ),
    },
  ];

  return (
    <SettingsLayout active="staff">
      <PageHeader
        title="مدیریت پرسنل"
        description="لیست پرسنل کلینیک / مطب"
        action={
          <button className="btn primary sm" onClick={() => setCreateOpen(true)}>
            <PlusIcon style={{ width: 16 }} /> افزودن پرسنل
          </button>
        }
      />

      {/* KPI bar */}
      {!isLoading && (
        <div className="stat-grid" style={{ marginBottom: 16 }}>
          <div className="card card-pad" style={{ textAlign: 'center' }}>
            <div style={{ fontSize: 28, fontWeight: 800, color: 'var(--text-1)' }}>{total}</div>
            <div style={{ fontSize: 13, color: 'var(--text-3)', marginTop: 2 }}>کل پرسنل</div>
          </div>
          <div className="card card-pad" style={{ textAlign: 'center' }}>
            <div style={{ fontSize: 28, fontWeight: 800, color: 'oklch(0.55 0.16 162)' }}>{active}</div>
            <div style={{ fontSize: 13, color: 'var(--text-3)', marginTop: 2 }}>فعال</div>
          </div>
          <div className="card card-pad" style={{ textAlign: 'center' }}>
            <div style={{ fontSize: 28, fontWeight: 800, color: 'oklch(0.55 0.18 25)' }}>{inactive}</div>
            <div style={{ fontSize: 13, color: 'var(--text-3)', marginTop: 2 }}>غیرفعال</div>
          </div>
        </div>
      )}

      <div className="card">
        {staff.length === 0 && !isLoading ? (
          <div style={{ textAlign: 'center', padding: '60px 24px', color: 'var(--text-3)' }}>
            <UserGroupIcon style={{ width: 48, margin: '0 auto 16px', display: 'block', opacity: 0.4 }} />
            <div style={{ fontWeight: 600, fontSize: 15, marginBottom: 8, color: 'var(--text-2)' }}>هنوز پرسنلی ثبت نشده</div>
            <div style={{ fontSize: 13, marginBottom: 20 }}>اولین عضو تیم خود را اضافه کنید</div>
            <button className="btn primary sm" onClick={() => setCreateOpen(true)}>
              <PlusIcon style={{ width: 16 }} /> افزودن پرسنل
            </button>
          </div>
        ) : (
          <DataTable columns={columns} data={staff} loading={isLoading} />
        )}
      </div>

      {/* Modal ایجاد */}
      <Modal open={createOpen} onClose={() => setCreateOpen(false)} title="افزودن پرسنل جدید">
        <form onSubmit={createForm.handleSubmit((d) => createMutation.mutate(d))}>
          <StaffFormFields form={createForm} />
          <div style={{ display: 'flex', gap: 8, marginTop: 16 }}>
            <button type="submit" className="btn primary" disabled={createMutation.isPending}>
              {createMutation.isPending ? 'در حال ذخیره...' : 'ذخیره'}
            </button>
            <button type="button" className="btn" onClick={() => setCreateOpen(false)}>انصراف</button>
          </div>
        </form>
      </Modal>

      {/* Modal ویرایش */}
      <Modal open={!!editTarget} onClose={() => setEditTarget(null)} title="ویرایش پرسنل">
        <form
          onSubmit={editForm.handleSubmit((d) =>
            editTarget && editMutation.mutate({ uuid: editTarget.uuid, body: d })
          )}
        >
          <StaffFormFields form={editForm} />
          <div style={{ display: 'flex', gap: 8, marginTop: 16 }}>
            <button type="submit" className="btn primary" disabled={editMutation.isPending}>
              {editMutation.isPending ? 'در حال ذخیره...' : 'ذخیره'}
            </button>
            <button type="button" className="btn" onClick={() => setEditTarget(null)}>انصراف</button>
          </div>
        </form>
      </Modal>

      {/* Confirm toggle */}
      <ConfirmDialog
        open={!!toggleTarget}
        title={toggleTarget?.active ? 'غیرفعال‌سازی پرسنل' : 'فعال‌سازی پرسنل'}
        message={`آیا مطمئن هستید که می‌خواهید «${toggleTarget?.full_name}» را ${toggleTarget?.active ? 'غیرفعال' : 'فعال'} کنید؟`}
        confirmLabel={toggleTarget?.active ? 'غیرفعال کن' : 'فعال کن'}
        onConfirm={() => toggleTarget && toggleMutation.mutate(toggleTarget.uuid)}
        onCancel={() => setToggleTarget(null)}
        loading={toggleMutation.isPending}
      />
    </SettingsLayout>
  );
}

function StaffFormFields({ form }: { form: ReturnType<typeof useForm<StaffFormData>> }) {
  const { register, formState: { errors } } = form;
  return (
    <div style={{ display: 'flex', flexDirection: 'column', gap: 12 }}>
      <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: 12 }}>
        <div className="field">
          <label>نام و نام خانوادگی *</label>
          <input {...register('full_name')} placeholder="علی رضایی" />
          {errors.full_name && <span className="field-error">{errors.full_name.message}</span>}
        </div>
        <div className="field">
          <label>سمت</label>
          <input {...register('job_title')} placeholder="پرستار" />
        </div>
      </div>
      <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: 12 }}>
        <div className="field">
          <label>تلفن</label>
          <input {...numericField(register('phone'), 11)} placeholder="09121234567" />
        </div>
        <div className="field">
          <label>کد ملی</label>
          <input {...numericField(register('national_code'), 10)} placeholder="0012345678" />
        </div>
      </div>
      <div className="field">
        <label>آدرس</label>
        <input {...register('address')} placeholder="آدرس محل سکونت" />
      </div>
    </div>
  );
}