import { useState, useEffect, useCallback } from 'react';
import {
  Users,
  Plus,
  Edit2,
  Trash2,
  Save,
  X,
  Loader2,
  RefreshCw,
  Search,
  Shield,
  Check,
} from 'lucide-react';
import { comms } from '@/communication';
import { UserGroupItem, PermissionInfo } from '@/types';

const initialFormData: Partial<UserGroupItem> = {
  dept: '',
  path_kj: '',
  permission: 0,
  advpurchase: false,
  advkisul: false,
  managerinfo: '',
  devinfo: '',
  usemail: false,
};

// 비트 연산 헬퍼 함수
const getBit = (value: number, index: number): boolean => {
  return ((value >> index) & 1) === 1;
};

const setBit = (value: number, index: number, flag: boolean): number => {
  if (flag) {
    return value | (1 << index);
  } else {
    return value & ~(1 << index);
  }
};

export function UserGroupPage() {
  const [loading, setLoading] = useState(false);
  const [groups, setGroups] = useState<UserGroupItem[]>([]);
  const [searchKey, setSearchKey] = useState('');
  const [showModal, setShowModal] = useState(false);
  const [showPermissionModal, setShowPermissionModal] = useState(false);
  const [editingItem, setEditingItem] = useState<UserGroupItem | null>(null);
  const [formData, setFormData] = useState<Partial<UserGroupItem>>(initialFormData);
  const [permissionInfo, setPermissionInfo] = useState<PermissionInfo[]>([]);
  const [saving, setSaving] = useState(false);

  const loadData = useCallback(async () => {
    setLoading(true);
    try {
      const [groupsRes, permRes] = await Promise.all([
        comms.getUserGroupList(),
        comms.getPermissionInfo()
      ]);

      if (groupsRes.Success && groupsRes.Data) {
        setGroups(groupsRes.Data);
      }
      if (permRes.Success && permRes.Data) {
        setPermissionInfo(permRes.Data);
      }
    } catch (error) {
      console.error('데이터 로드 오류:', error);
      alert('데이터를 불러오는 중 오류가 발생했습니다.');
    } finally {
      setLoading(false);
    }
  }, []);

  useEffect(() => {
    loadData();
  }, [loadData]);

  const filteredItems = groups.filter(item =>
    !searchKey ||
    item.dept?.toLowerCase().includes(searchKey.toLowerCase()) ||
    item.managerinfo?.toLowerCase().includes(searchKey.toLowerCase())
  );

  const openAddModal = () => {
    setEditingItem(null);
    setFormData(initialFormData);
    setShowModal(true);
  };

  const openEditModal = (item: UserGroupItem) => {
    setEditingItem(item);
    setFormData({
      dept: item.dept || '',
      path_kj: item.path_kj || '',
      permission: item.permission || 0,
      advpurchase: item.advpurchase || false,
      advkisul: item.advkisul || false,
      managerinfo: item.managerinfo || '',
      devinfo: item.devinfo || '',
      usemail: item.usemail || false,
    });
    setShowModal(true);
  };

  const openPermissionModal = (item: UserGroupItem) => {
    setEditingItem(item);
    setFormData({
      ...formData,
      dept: item.dept,
      permission: item.permission || 0,
    });
    setShowPermissionModal(true);
  };

  const handlePermissionChange = (index: number, checked: boolean) => {
    const newPermission = setBit(formData.permission || 0, index, checked);
    setFormData({ ...formData, permission: newPermission });
  };

  const handleSavePermission = async () => {
    if (!editingItem) return;

    setSaving(true);
    try {
      const response = await comms.editUserGroup(
        editingItem.dept,
        editingItem.dept,
        editingItem.path_kj || '',
        formData.permission || 0,
        editingItem.advpurchase || false,
        editingItem.advkisul || false,
        editingItem.managerinfo || '',
        editingItem.devinfo || '',
        editingItem.usemail || false
      );

      if (response.Success) {
        setShowPermissionModal(false);
        loadData();
      } else {
        alert(response.Message || '저장에 실패했습니다.');
      }
    } catch (error) {
      console.error('저장 오류:', error);
      alert('저장 중 오류가 발생했습니다.');
    } finally {
      setSaving(false);
    }
  };

  const handleSave = async () => {
    if (!formData.dept?.trim()) {
      alert('부서명을 입력해주세요.');
      return;
    }

    setSaving(true);
    try {
      let response;
      if (editingItem) {
        response = await comms.editUserGroup(
          editingItem.dept,
          formData.dept || '',
          formData.path_kj || '',
          formData.permission || 0,
          formData.advpurchase || false,
          formData.advkisul || false,
          formData.managerinfo || '',
          formData.devinfo || '',
          formData.usemail || false
        );
      } else {
        response = await comms.addUserGroup(
          formData.dept || '',
          formData.path_kj || '',
          formData.permission || 0,
          formData.advpurchase || false,
          formData.advkisul || false,
          formData.managerinfo || '',
          formData.devinfo || '',
          formData.usemail || false
        );
      }

      if (response.Success) {
        setShowModal(false);
        loadData();
      } else {
        alert(response.Message || '저장에 실패했습니다.');
      }
    } catch (error) {
      console.error('저장 오류:', error);
      alert('저장 중 오류가 발생했습니다.');
    } finally {
      setSaving(false);
    }
  };

  const handleDelete = async (item: UserGroupItem) => {
    if (!confirm(`"${item.dept}" 그룹을 삭제하시겠습니까?`)) return;

    try {
      const response = await comms.deleteUserGroup(item.dept);
      if (response.Success) {
        loadData();
      } else {
        alert(response.Message || '삭제에 실패했습니다.');
      }
    } catch (error) {
      console.error('삭제 오류:', error);
      alert('삭제 중 오류가 발생했습니다.');
    }
  };

  // 권한 카운트 계산
  const getPermissionCount = (permission: number): number => {
    let count = 0;
    for (let i = 0; i < 11; i++) {
      if (getBit(permission, i)) count++;
    }
    return count;
  };

  return (
    <div className="space-y-6">
      {/* 헤더 */}
      <div className="glass-effect rounded-2xl p-6">
        <div className="flex flex-col md:flex-row md:items-center md:justify-between gap-4">
          <div className="flex items-center space-x-3">
            <div className="p-3 bg-primary-500/20 rounded-xl">
              <Users className="w-6 h-6 text-primary-400" />
            </div>
            <div>
              <h1 className="text-2xl font-bold text-white">그룹정보</h1>
              <p className="text-white/60 text-sm">부서/그룹 및 권한 관리</p>
            </div>
          </div>

          <div className="flex items-center space-x-3">
            {/* 검색 */}
            <div className="relative">
              <Search className="absolute left-3 top-1/2 transform -translate-y-1/2 w-4 h-4 text-white/40" />
              <input
                type="text"
                value={searchKey}
                onChange={(e) => setSearchKey(e.target.value)}
                placeholder="부서명 검색..."
                className="pl-10 pr-4 py-2 bg-white/10 border border-white/10 rounded-lg text-white text-sm focus:outline-none focus:border-primary-500 w-48"
              />
            </div>

            <button
              onClick={loadData}
              disabled={loading}
              className="flex items-center space-x-2 px-4 py-2 bg-white/10 hover:bg-white/20 rounded-lg text-white transition-colors disabled:opacity-50"
            >
              <RefreshCw className={`w-4 h-4 ${loading ? 'animate-spin' : ''}`} />
            </button>

            <button
              onClick={openAddModal}
              className="flex items-center space-x-2 px-4 py-2 bg-primary-500 hover:bg-primary-600 rounded-lg text-white transition-colors"
            >
              <Plus className="w-4 h-4" />
              <span>새 그룹</span>
            </button>
          </div>
        </div>
      </div>

      {/* 목록 */}
      <div className="glass-effect rounded-2xl overflow-hidden">
        {loading ? (
          <div className="flex items-center justify-center py-20">
            <Loader2 className="w-8 h-8 text-white animate-spin" />
          </div>
        ) : filteredItems.length === 0 ? (
          <div className="flex flex-col items-center justify-center py-20 text-white/50">
            <Users className="w-12 h-12 mb-4 opacity-50" />
            <p>등록된 그룹이 없습니다.</p>
          </div>
        ) : (
          <div className="overflow-x-auto">
            <table className="w-full">
              <thead className="bg-white/10">
                <tr>
                  <th className="px-4 py-3 text-left text-xs font-medium text-white/70 uppercase">부서명</th>
                  <th className="px-4 py-3 text-left text-xs font-medium text-white/70 uppercase">경로</th>
                  <th className="px-4 py-3 text-center text-xs font-medium text-white/70 uppercase w-24">권한</th>
                  <th className="px-4 py-3 text-center text-xs font-medium text-white/70 uppercase w-20">구매고급</th>
                  <th className="px-4 py-3 text-center text-xs font-medium text-white/70 uppercase w-20">기술고급</th>
                  <th className="px-4 py-3 text-center text-xs font-medium text-white/70 uppercase w-20">메일</th>
                  <th className="px-4 py-3 text-left text-xs font-medium text-white/70 uppercase">관리자정보</th>
                  <th className="px-4 py-3 text-center text-xs font-medium text-white/70 uppercase w-28">작업</th>
                </tr>
              </thead>
              <tbody className="divide-y divide-white/5">
                {filteredItems.map((item, index) => (
                  <tr key={`${item.dept}-${index}`} className="hover:bg-white/5 transition-colors">
                    <td className="px-4 py-3 text-white font-medium">{item.dept}</td>
                    <td className="px-4 py-3 text-white/70 text-sm">{item.path_kj || '-'}</td>
                    <td className="px-4 py-3 text-center">
                      <button
                        onClick={() => openPermissionModal(item)}
                        className="inline-flex items-center space-x-1 px-2 py-1 bg-primary-500/20 text-primary-400 rounded text-xs hover:bg-primary-500/30 transition-colors"
                      >
                        <Shield className="w-3 h-3" />
                        <span>{getPermissionCount(item.permission || 0)}</span>
                      </button>
                    </td>
                    <td className="px-4 py-3 text-center">
                      {item.advpurchase && <Check className="w-4 h-4 text-success-400 mx-auto" />}
                    </td>
                    <td className="px-4 py-3 text-center">
                      {item.advkisul && <Check className="w-4 h-4 text-success-400 mx-auto" />}
                    </td>
                    <td className="px-4 py-3 text-center">
                      {item.usemail && <Check className="w-4 h-4 text-success-400 mx-auto" />}
                    </td>
                    <td className="px-4 py-3 text-white/70 text-sm truncate max-w-48">{item.managerinfo || '-'}</td>
                    <td className="px-4 py-3">
                      <div className="flex items-center justify-center space-x-2">
                        <button
                          onClick={() => openEditModal(item)}
                          className="p-1.5 hover:bg-white/10 rounded text-white/70 hover:text-white transition-colors"
                          title="수정"
                        >
                          <Edit2 className="w-4 h-4" />
                        </button>
                        <button
                          onClick={() => handleDelete(item)}
                          className="p-1.5 hover:bg-danger-500/20 rounded text-white/70 hover:text-danger-400 transition-colors"
                          title="삭제"
                        >
                          <Trash2 className="w-4 h-4" />
                        </button>
                      </div>
                    </td>
                  </tr>
                ))}
              </tbody>
            </table>
          </div>
        )}
      </div>

      {/* 그룹 편집 모달 */}
      {showModal && (
        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50 p-4">
          <div className="bg-slate-800 rounded-2xl w-full max-w-2xl max-h-[90vh] overflow-hidden flex flex-col">
            {/* 모달 헤더 */}
            <div className="flex items-center justify-between px-6 py-4 border-b border-white/10">
              <h2 className="text-xl font-bold text-white">
                {editingItem ? '그룹 수정' : '새 그룹'}
              </h2>
              <button
                onClick={() => setShowModal(false)}
                className="p-2 hover:bg-white/10 rounded-lg text-white/70 hover:text-white transition-colors"
              >
                <X className="w-5 h-5" />
              </button>
            </div>

            {/* 모달 내용 */}
            <div className="flex-1 overflow-y-auto p-6 space-y-4">
              {/* 부서명 */}
              <div>
                <label className="block text-white/70 text-sm mb-1">부서명 *</label>
                <input
                  type="text"
                  value={formData.dept || ''}
                  onChange={(e) => setFormData({ ...formData, dept: e.target.value })}
                  className="w-full px-3 py-2 bg-white/10 border border-white/10 rounded-lg text-white focus:outline-none focus:border-primary-500"
                />
              </div>

              {/* 경로 */}
              <div>
                <label className="block text-white/70 text-sm mb-1">경로 (path_kj)</label>
                <input
                  type="text"
                  value={formData.path_kj || ''}
                  onChange={(e) => setFormData({ ...formData, path_kj: e.target.value })}
                  className="w-full px-3 py-2 bg-white/10 border border-white/10 rounded-lg text-white focus:outline-none focus:border-primary-500"
                />
              </div>

              {/* 체크박스들 */}
              <div className="grid grid-cols-3 gap-4">
                <label className="flex items-center space-x-2 text-white/70">
                  <input
                    type="checkbox"
                    checked={formData.advpurchase || false}
                    onChange={(e) => setFormData({ ...formData, advpurchase: e.target.checked })}
                    className="w-4 h-4 rounded"
                  />
                  <span>구매고급</span>
                </label>
                <label className="flex items-center space-x-2 text-white/70">
                  <input
                    type="checkbox"
                    checked={formData.advkisul || false}
                    onChange={(e) => setFormData({ ...formData, advkisul: e.target.checked })}
                    className="w-4 h-4 rounded"
                  />
                  <span>기술고급</span>
                </label>
                <label className="flex items-center space-x-2 text-white/70">
                  <input
                    type="checkbox"
                    checked={formData.usemail || false}
                    onChange={(e) => setFormData({ ...formData, usemail: e.target.checked })}
                    className="w-4 h-4 rounded"
                  />
                  <span>메일 사용</span>
                </label>
              </div>

              {/* 관리자 정보 */}
              <div>
                <label className="block text-white/70 text-sm mb-1">관리자 정보</label>
                <textarea
                  value={formData.managerinfo || ''}
                  onChange={(e) => setFormData({ ...formData, managerinfo: e.target.value })}
                  rows={2}
                  className="w-full px-3 py-2 bg-white/10 border border-white/10 rounded-lg text-white focus:outline-none focus:border-primary-500 resize-none"
                />
              </div>

              {/* 개발자 정보 */}
              <div>
                <label className="block text-white/70 text-sm mb-1">개발자 정보</label>
                <textarea
                  value={formData.devinfo || ''}
                  onChange={(e) => setFormData({ ...formData, devinfo: e.target.value })}
                  rows={2}
                  className="w-full px-3 py-2 bg-white/10 border border-white/10 rounded-lg text-white focus:outline-none focus:border-primary-500 resize-none"
                />
              </div>
            </div>

            {/* 모달 푸터 */}
            <div className="flex items-center justify-end space-x-3 px-6 py-4 border-t border-white/10">
              <button
                onClick={() => setShowModal(false)}
                className="px-4 py-2 bg-white/10 hover:bg-white/20 rounded-lg text-white transition-colors"
              >
                취소
              </button>
              <button
                onClick={handleSave}
                disabled={saving}
                className="flex items-center space-x-2 px-4 py-2 bg-primary-500 hover:bg-primary-600 rounded-lg text-white transition-colors disabled:opacity-50"
              >
                {saving ? (
                  <Loader2 className="w-4 h-4 animate-spin" />
                ) : (
                  <Save className="w-4 h-4" />
                )}
                <span>저장</span>
              </button>
            </div>
          </div>
        </div>
      )}

      {/* 권한 설정 모달 */}
      {showPermissionModal && editingItem && (
        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50 p-4">
          <div className="bg-slate-800 rounded-2xl w-full max-w-md max-h-[90vh] overflow-hidden flex flex-col">
            {/* 모달 헤더 */}
            <div className="flex items-center justify-between px-6 py-4 border-b border-white/10">
              <div>
                <h2 className="text-xl font-bold text-white">권한 설정</h2>
                <p className="text-white/60 text-sm">{editingItem.dept}</p>
              </div>
              <button
                onClick={() => setShowPermissionModal(false)}
                className="p-2 hover:bg-white/10 rounded-lg text-white/70 hover:text-white transition-colors"
              >
                <X className="w-5 h-5" />
              </button>
            </div>

            {/* 모달 내용 */}
            <div className="flex-1 overflow-y-auto p-6">
              <div className="grid grid-cols-2 gap-3">
                {permissionInfo.map((perm) => (
                  <label
                    key={perm.index}
                    className="flex items-center space-x-2 p-2 rounded-lg hover:bg-white/5 cursor-pointer"
                    title={perm.description}
                  >
                    <input
                      type="checkbox"
                      checked={getBit(formData.permission || 0, perm.index)}
                      onChange={(e) => handlePermissionChange(perm.index, e.target.checked)}
                      className="w-4 h-4 rounded"
                    />
                    <span className="text-white/80 text-sm">{perm.label}</span>
                  </label>
                ))}
              </div>
            </div>

            {/* 모달 푸터 */}
            <div className="flex items-center justify-end space-x-3 px-6 py-4 border-t border-white/10">
              <button
                onClick={() => setShowPermissionModal(false)}
                className="px-4 py-2 bg-white/10 hover:bg-white/20 rounded-lg text-white transition-colors"
              >
                취소
              </button>
              <button
                onClick={handleSavePermission}
                disabled={saving}
                className="flex items-center space-x-2 px-4 py-2 bg-primary-500 hover:bg-primary-600 rounded-lg text-white transition-colors disabled:opacity-50"
              >
                {saving ? (
                  <Loader2 className="w-4 h-4 animate-spin" />
                ) : (
                  <Save className="w-4 h-4" />
                )}
                <span>저장</span>
              </button>
            </div>
          </div>
        </div>
      )}
    </div>
  );
}