import React, { useState } from 'react';
import { useNavigate } from 'react-router-dom';
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
import {
  PlusIcon, PencilIcon, WrenchScrewdriverIcon, BanknotesIcon,
  ShieldCheckIcon, MagnifyingGlassIcon, EyeIcon, EyeSlashIcon,
  EllipsisHorizontalIcon, CheckCircleIcon, XCircleIcon, ChevronRightIcon,
  XMarkIcon, UsersIcon, ClockIcon,
} 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 { ServiceSection, ServiceItem } from '../types';
import { formatRial, formatNumber } from '../lib/utils';
import { usePermissions } from '../hooks/usePermissions';
import PageHeader from '../components/ui/PageHeader';
import Modal from '../components/ui/Modal';
import ConfirmDialog from '../components/ui/ConfirmDialog';
import ServiceTariffModal from '../components/ServiceTariffModal';
import ServiceInsuranceModal from '../components/ServiceInsuranceModal';
import ServiceItemFormModal from '../components/ServiceItemFormModal';
import FeatureGate from '../components/ui/FeatureGate';

const sectionSchema = z.object({ name: z.string().min(1, 'نام بخش الزامی است') });
type SectionForm = z.infer<typeof sectionSchema>;

const EMPTY_SECTIONS: ServiceSection[] = [];
const EMPTY_ITEMS: ServiceItem[] = [];

function Avatar({ name }: { name: string }) {
  return (
    <div style={{
      width: 26, height: 26, borderRadius: '50%',
      background: 'linear-gradient(145deg, oklch(0.62 0.15 162), oklch(0.48 0.16 162))',
      display: 'flex', alignItems: 'center', justifyContent: 'center',
      fontSize: 11, fontWeight: 700, color: 'var(--on-primary)', flexShrink: 0,
    }}>
      {name.charAt(0)}
    </div>
  );
}

function ClinicServicesPageInner() {
  const qc = useQueryClient();
  // مجوزهای منشی؛ برای owner/پزشک همیشه true (usePermissions بدون context آزاد است).
  const { can } = usePermissions();
  const canCreate = can('services', 'create');
  const canUpdate = can('services', 'update');
  const navigate = useNavigate();

  const [selectedSection, setSelectedSection] = useState<ServiceSection | null>(null);
  const [sectionModal, setSectionModal] = useState<'create' | ServiceSection | null>(null);
  const [itemModal, setItemModal] = useState<'create' | ServiceItem | null>(null);
  const [toggleItem, setToggleItem] = useState<ServiceItem | null>(null);
  const [tariffItem, setTariffItem] = useState<ServiceItem | null>(null);
  const [insuranceItem, setInsuranceItem] = useState<ServiceItem | null>(null);
  const [search, setSearch] = useState('');
  const [showInactive, setShowInactive] = useState(true);
  const [menuOpen, setMenuOpen] = useState<string | null>(null);

  const { data: sectionsData, isLoading: sectionsLoading } = useQuery<ApiResponse<ServiceSection[]>>({
    queryKey: ['service-sections'],
    queryFn: () => api.get('/api/v1/service-sections'),
  });

  const { data: itemsData, isLoading: itemsLoading } = useQuery<ApiResponse<ServiceItem[]>>({
    queryKey: ['service-items', selectedSection?.uuid],
    queryFn: () => api.get(`/api/v1/service-items/${selectedSection!.uuid}`),
    enabled: !!selectedSection,
  });

  const sections = sectionsData?.data ?? EMPTY_SECTIONS;
  const allItems = itemsData?.data ?? EMPTY_ITEMS;

  const sectionForm = useForm<SectionForm>({ resolver: zodResolver(sectionSchema) });

  const items = allItems.filter((it) => {
    if (!showInactive && !it.active) return false;
    if (search.trim() && !it.name.includes(search.trim())) return false;
    return true;
  });
  const activeCount = allItems.filter((i) => i.active).length;

  const createSection = useMutation({
    mutationFn: (body: SectionForm) => api.post('/api/v1/service-section', body),
    onSuccess: () => { qc.invalidateQueries({ queryKey: ['service-sections'] }); setSectionModal(null); sectionForm.reset(); toast.success('بخش ایجاد شد'); },
    onError: (e: any) => toast.error(e.message),
  });

  const editSection = useMutation({
    mutationFn: ({ uuid, body }: { uuid: string; body: SectionForm }) =>
      api.patch(`/api/v1/service-section/${uuid}`, body),
    onSuccess: () => { qc.invalidateQueries({ queryKey: ['service-sections'] }); setSectionModal(null); toast.success('بخش ویرایش شد'); },
    onError: (e: any) => toast.error(e.message),
  });

  const toggleSection = useMutation({
    mutationFn: ({ uuid, active }: { uuid: string; active: boolean }) =>
      api.patch(`/api/v1/service-section/${uuid}`, { active }),
    onSuccess: (_d, v) => {
      qc.invalidateQueries({ queryKey: ['service-sections'] });
      toast.success(v.active ? 'بخش فعال شد' : 'بخش غیرفعال شد');
    },
    onError: (e: any) => toast.error(e.message),
  });

  const toggleActive = useMutation({
    mutationFn: ({ uuid, active }: { uuid: string; active: boolean }) =>
      api.patch(`/api/v1/service-item/${uuid}`, { active }),
    onSuccess: (_d, v) => {
      qc.invalidateQueries({ queryKey: ['service-items', selectedSection?.uuid] });
      setToggleItem(null);
      toast.success(v.active ? 'سرویس فعال شد' : 'سرویس غیرفعال شد');
    },
    onError: (e: any) => { toast.error(e.message); setToggleItem(null); },
  });

  const openEditSection = (s: ServiceSection) => {
    sectionForm.reset({ name: s.name });
    setSectionModal(s);
  };

  const openCreateItem = () => setItemModal('create');

  return (
    <>
      {!selectedSection ? (
        /* ═════════ نمای بخش‌ها ═════════ */
        <>
          {/* تیتر دست‌ساز جای `PageHeader` بود: بدون آن این صفحه تنها فهرستِ پنل است
              که نه دکمهٔ بازگشت دارد و نه می‌گوید چیست. */}
          <PageHeader
            title="سرویس‌ها"
            description="بخش‌ها و سرویس‌های قابل رزرو. مدت و قیمت هر سرویس از همین‌جا می‌آید."
            backTo="/admin/settings-menu"
            action={
              canCreate ? (
                <button className="cp-btn-primary" onClick={() => { sectionForm.reset({ name: '' }); setSectionModal('create'); }}>
                  <PlusIcon style={{ width: 16 }} /> بخش جدید
                </button>
              ) : undefined
            }
          />

          {sectionsLoading ? (
            <div style={{ color: 'var(--text-3)', fontSize: 13, padding: 16 }}>در حال بارگذاری...</div>
          ) : sections.length === 0 ? (
            <div className="card" style={{ padding: '60px 0', textAlign: 'center', color: 'var(--text-3)' }}>
              <WrenchScrewdriverIcon style={{ width: 56, margin: '0 auto 16px', display: 'block', opacity: 0.3 }} />
              <div style={{ fontSize: 14, color: 'var(--text-2)' }}>برای اضافه کردن بخش روی دکمه بخش جدید کلیک نمایید.</div>
            </div>
          ) : (
            <div style={{ display: 'grid', gridTemplateColumns: 'repeat(auto-fill, minmax(240px, 1fr))', gap: 14 }}>
              {sections.map((s) => (
                <div
                  key={s.uuid}
                  onClick={() => setSelectedSection(s)}
                  style={{
                    cursor: 'pointer', background: 'var(--surface)', borderRadius: 'var(--r)',
                    boxShadow: '0 1px 24.8px rgba(204,204,204,0.18)',
                    border: '1px solid var(--border)', padding: '16px 16px 12px',
                    opacity: s.active ? 1 : 0.62,
                  }}
                >
                  <div style={{ fontWeight: 700, fontSize: 15, color: 'var(--text)', marginBottom: 12 }}>{s.name}</div>

                  <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', padding: '4px 0' }}>
                    <span style={{ fontSize: 12.5, color: 'var(--text-3)' }}>تعداد:</span>
                    <span style={{ fontSize: 13, color: 'var(--text-2)' }}>{formatNumber(s.items_count ?? 0)} سرویس</span>
                  </div>
                  <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', padding: '4px 0' }} onClick={(e) => e.stopPropagation()}>
                    <span style={{ fontSize: 12.5, color: 'var(--text-3)' }}>وضعیت:</span>
                    <span style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
                      <label className="switch" title={s.active ? 'فعال' : 'غیرفعال'}>
                        <input type="checkbox" checked={s.active} onChange={() => toggleSection.mutate({ uuid: s.uuid, active: !s.active })} />
                        <span className="switch-track"><span className="switch-thumb" /></span>
                      </label>
                      <span style={{ fontSize: 12.5, color: s.active ? 'var(--success)' : 'var(--text-3)' }}>{s.active ? 'فعال' : 'غیرفعال'}</span>
                    </span>
                  </div>

                  {canUpdate && (
                    <div style={{ display: 'flex', gap: 6, borderTop: '1px solid var(--border)', paddingTop: 10, marginTop: 8 }} onClick={(e) => e.stopPropagation()}>
                      <button className="btn sm ghost" aria-label="ویرایش" style={{ display: 'flex', alignItems: 'center', gap: 4, color: 'var(--text-2)' }} onClick={() => openEditSection(s)}>
                        <PencilIcon style={{ width: 15 }} />
                      </button>
                    </div>
                  )}
                </div>
              ))}
            </div>
          )}
        </>
      ) : (
        /* ═════════ نمای سرویس‌های یک بخش ═════════ */
        <>
          <div style={{ display: 'flex', alignItems: 'center', justifyContent: 'space-between', marginBottom: 16, flexWrap: 'wrap', gap: 12 }}>
            <div style={{ display: 'flex', alignItems: 'center', gap: 10, flexWrap: 'wrap' }}>
              <button className="cp-btn-secondary" style={{ height: 36 }} onClick={() => setSelectedSection(null)}>
                <ChevronRightIcon style={{ width: 16 }} /> بازگشت
              </button>
              <div style={{ display: 'flex', alignItems: 'center', gap: 6, fontSize: 14, color: 'var(--text-3)' }}>
                <span style={{ cursor: 'pointer' }} onClick={() => setSelectedSection(null)}>بخش‌ها</span>
                <span>‹</span>
                <b style={{ color: 'var(--text)' }}>{selectedSection.name}</b>
              </div>
            </div>
            <div style={{ display: 'flex', alignItems: 'center', gap: 8, flexWrap: 'wrap' }}>
              <div style={{ position: 'relative' }}>
                <MagnifyingGlassIcon style={{ width: 15, position: 'absolute', insetInlineStart: 9, top: '50%', transform: 'translateY(-50%)', color: 'var(--text-3)', pointerEvents: 'none' }} />
                <input className="cp-input" placeholder="جستجوی سرویس" value={search} onChange={(e) => setSearch(e.target.value)} style={{ width: 170, paddingInlineStart: 30, height: 36 }} />
              </div>
              <button className="btn sm ghost" onClick={() => setShowInactive((v) => !v)} title={showInactive ? 'پنهان‌کردن غیرفعال‌ها' : 'نمایش غیرفعال‌ها'}>
                {showInactive ? <EyeIcon style={{ width: 16 }} /> : <EyeSlashIcon style={{ width: 16 }} />}
              </button>
              {canCreate && (
                <button className="cp-btn-primary" onClick={openCreateItem}>
                  <PlusIcon style={{ width: 16 }} /> سرویس جدید
                </button>
              )}
            </div>
          </div>

          {itemsLoading ? (
            <div style={{ color: 'var(--text-3)', fontSize: 13, padding: 16 }}>در حال بارگذاری...</div>
          ) : items.length === 0 ? (
            <div className="card" style={{ padding: '52px 0', textAlign: 'center', color: 'var(--text-3)' }}>
              <PlusIcon style={{ width: 32, margin: '0 auto 12px', display: 'block', opacity: 0.35 }} />
              <div style={{ fontWeight: 600, color: 'var(--text-2)', marginBottom: 4 }}>
                {allItems.length === 0 ? 'سرویسی در این بخش وجود ندارد' : 'سرویسی با این فیلتر یافت نشد'}
              </div>
              {allItems.length === 0 && canCreate && (
                <button className="cp-btn-primary" style={{ marginTop: 12 }} onClick={openCreateItem}>افزودن سرویس</button>
              )}
            </div>
          ) : (
            <div style={{ display: 'grid', gridTemplateColumns: 'repeat(auto-fill, minmax(300px, 1fr))', gap: 16 }}>
              {items.map((item) => {
                const menuItemStyle: React.CSSProperties = {
                  display: 'flex', alignItems: 'center', gap: 8, width: '100%',
                  padding: '8px 10px', borderRadius: 8, border: 'none', cursor: 'pointer',
                  background: 'transparent', color: 'var(--text-2)', fontSize: 13,
                  fontFamily: 'inherit', textAlign: 'start', whiteSpace: 'nowrap',
                };
                const chipStyle: React.CSSProperties = {
                  fontSize: 12, color: 'var(--text-2)', background: 'var(--surface-2)',
                  border: '1px solid var(--border)', borderRadius: 999, padding: '3px 10px', whiteSpace: 'nowrap',
                };
                return (
                  <div
                    key={item.uuid}
                    role="link"
                    tabIndex={0}
                    onClick={() => navigate(`/admin/clinic-services/${item.uuid}`)}
                    onKeyDown={(e) => { if (e.key === 'Enter') navigate(`/admin/clinic-services/${item.uuid}`); }}
                    style={{
                      position: 'relative', background: 'var(--surface)', borderRadius: 8,
                      boxShadow: '0 1px 24.8px rgba(204,204,204,0.18)',
                      border: '1px solid var(--border)', padding: 14, cursor: 'pointer',
                      opacity: item.active ? 1 : 0.7,
                    }}
                  >
                    {/* نوار بالا: ⋮ (چپ) + وضعیت و نام (راست) */}
                    <div style={{ display: 'flex', alignItems: 'flex-start', justifyContent: 'space-between', gap: 8, marginBottom: 14 }}>
                      {canUpdate ? (
                        <button className="btn sm ghost" style={{ padding: 4 }} onClick={(e) => { e.stopPropagation(); setMenuOpen(menuOpen === item.uuid ? null : item.uuid); }} title="عملیات">
                          <EllipsisHorizontalIcon style={{ width: 20 }} />
                        </button>
                      ) : <span />}
                      <div style={{ display: 'flex', alignItems: 'center', gap: 8, minWidth: 0 }}>
                        <span className={`badge ${item.active ? 'green' : 'gray'}`} style={{ fontSize: 11 }}>
                          <span className="bdot" />{item.active ? 'فعال' : 'غیرفعال'}
                        </span>
                        <span style={{ fontWeight: 700, fontSize: 14, color: 'var(--text)', whiteSpace: 'nowrap', overflow: 'hidden', textOverflow: 'ellipsis' }}>{item.name}</span>
                      </div>
                    </div>
                    {menuOpen === item.uuid && (
                      <>
                        <div style={{ position: 'fixed', inset: 0, zIndex: 40 }} onClick={(e) => { e.stopPropagation(); setMenuOpen(null); }} />
                        <div onClick={(e) => e.stopPropagation()} style={{ position: 'absolute', top: 40, insetInlineStart: 8, zIndex: 41, background: 'var(--surface)', border: '1px solid var(--border)', borderRadius: 'var(--r-sm)', boxShadow: 'var(--shadow)', padding: 6, minWidth: 176, display: 'flex', flexDirection: 'column', gap: 2 }}>
                          <button style={menuItemStyle} onClick={() => { setMenuOpen(null); setItemModal(item); }}><PencilIcon style={{ width: 15 }} /> ویرایش</button>
                          <button style={menuItemStyle} onClick={() => { setMenuOpen(null); setTariffItem(item); }}><BanknotesIcon style={{ width: 15 }} /> تعرفه‌های سالانه</button>
                          <button style={menuItemStyle} onClick={() => { setMenuOpen(null); setInsuranceItem(item); }}><ShieldCheckIcon style={{ width: 15 }} /> پوشش بیمه</button>
                          <button style={menuItemStyle} onClick={() => { setMenuOpen(null); setToggleItem(item); }}>{item.active ? <EyeSlashIcon style={{ width: 15 }} /> : <EyeIcon style={{ width: 15 }} />}{item.active ? ' غیرفعال‌کردن' : ' فعال‌کردن'}</button>
                        </div>
                      </>
                    )}

                    <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'baseline', gap: 8, padding: '3px 0' }}>
                      <span style={{ fontSize: 12, color: 'var(--text-3)', display: 'inline-flex', alignItems: 'center', gap: 5 }}>
                        <BanknotesIcon style={{ width: 14, color: 'var(--text-3)' }} /> قیمت پایه:
                      </span>
                      <span style={{ fontSize: 14, fontWeight: 800, color: 'var(--primary)' }}>{formatRial(item.price_rials)}</span>
                    </div>

                    <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', gap: 8, padding: '3px 0' }}>
                      <span style={{ fontSize: 12, color: 'var(--text-3)', display: 'inline-flex', alignItems: 'center', gap: 5 }}>
                        <ClockIcon style={{ width: 14, color: 'var(--text-3)' }} /> زمان متوسط:
                      </span>
                      <span style={{ display: 'inline-flex', alignItems: 'center', gap: 6 }}>
                        {item.bookable && <span className="badge green" style={{ fontSize: 11 }}>در نوبت‌دهی</span>}
                        {item.duration_minutes
                          ? <span className="badge blue" style={{ fontSize: 11 }}>{formatNumber(Number(item.duration_minutes))} دقیقه</span>
                          : <span style={{ fontSize: 12, color: 'var(--text-3)' }}>—</span>}
                      </span>
                    </div>

                    <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', gap: 8, padding: '3px 0' }}>
                      <span style={{ fontSize: 12, color: 'var(--text-3)', display: 'inline-flex', alignItems: 'center', gap: 5 }}>
                        <ShieldCheckIcon style={{ width: 14, color: 'var(--text-3)' }} /> بیمه:
                      </span>
                      {item.insurance_covered
                        ? <span className="badge green" style={{ fontSize: 11 }}>تحت پوشش</span>
                        : <span style={{ fontSize: 12, color: 'var(--text-3)' }}>—</span>}
                    </div>

                    <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'flex-start', gap: 8, padding: '3px 0' }}>
                      <span style={{ fontSize: 12, color: 'var(--text-3)', flexShrink: 0, display: 'inline-flex', alignItems: 'center', gap: 5 }}>
                        <UsersIcon style={{ width: 14, color: 'var(--text-3)' }} /> پرسنل:
                      </span>
                      <div style={{ display: 'flex', gap: 4, flexWrap: 'wrap', justifyContent: 'flex-end' }}>
                        {(item.staff_members && item.staff_members.length > 0)
                          ? item.staff_members.map((m) => <span key={m.uuid} style={chipStyle}>{m.full_name}</span>)
                          : item.staff
                            ? <span style={chipStyle}>{item.staff.full_name}</span>
                            : <span style={{ fontSize: 12, color: 'var(--text-3)' }}>—</span>}
                      </div>
                    </div>
                  </div>
                );
              })}
            </div>
          )}
        </>
      )}

      {/* ───────── Modal بخش ───────── */}
      <Modal
        open={sectionModal !== null}
        onClose={() => setSectionModal(null)}
        title={sectionModal === 'create' ? 'بخش جدید' : 'ویرایش بخش'}
      >
        <form onSubmit={sectionForm.handleSubmit((d) => {
          if (sectionModal === 'create') createSection.mutate(d);
          else if (sectionModal !== null && typeof sectionModal === 'object') editSection.mutate({ uuid: sectionModal.uuid, body: d });
        })}>
          <div className="field">
            <label>نام بخش *</label>
            <input {...sectionForm.register('name')} placeholder="مثلاً: تزریقات" autoFocus />
            {sectionForm.formState.errors.name && (
              <span className="field-error">{sectionForm.formState.errors.name.message}</span>
            )}
          </div>
          <div style={{ display: 'flex', gap: 8, marginTop: 18 }}>
            <button type="submit" className="btn primary" disabled={createSection.isPending || editSection.isPending}>ذخیره</button>
            <button type="button" className="btn" onClick={() => setSectionModal(null)}>انصراف</button>
          </div>
        </form>
      </Modal>

      {/* ───────── Modal سرویس ───────── */}
      <ServiceItemFormModal
        item={itemModal}
        sectionUuid={selectedSection?.uuid ?? null}
        onClose={() => setItemModal(null)}
        onManageInsurance={setInsuranceItem}
      />
      <ServiceTariffModal item={tariffItem} onClose={() => setTariffItem(null)} />

      <ServiceInsuranceModal item={insuranceItem} onClose={() => setInsuranceItem(null)} />

      {/* Confirm فعال/غیرفعال سرویس */}
      <ConfirmDialog
        open={!!toggleItem}
        title={toggleItem?.active ? 'غیرفعال‌کردن سرویس' : 'فعال‌کردن سرویس'}
        message={
          toggleItem?.active
            ? `سرویس «${toggleItem?.name}» غیرفعال می‌شود و در پذیرش جدید نمایش داده نمی‌شود. سوابق قبلی حفظ می‌مانند.`
            : `سرویس «${toggleItem?.name}» دوباره فعال و قابل انتخاب می‌شود.`
        }
        confirmLabel={toggleItem?.active ? 'غیرفعال کن' : 'فعال کن'}
        onConfirm={() => toggleItem && toggleActive.mutate({ uuid: toggleItem.uuid, active: !toggleItem.active })}
        onCancel={() => setToggleItem(null)}
        loading={toggleActive.isPending}
      />
    </>
  );
}

export default function ClinicServicesPage() {
  return (
    <FeatureGate feature="services">
      <ClinicServicesPageInner />
    </FeatureGate>
  );
}
