import { MoreHorizontal, Plus } from 'lucide-react';
import { useEffect, useMemo, useState } from 'react';
import { DataTableCard, type DataTableColumn, type DataTableFilter } from '../../components/data-table';
import { Button, Modal } from '../../components/ui';
import { useToast } from '../../components/toast';
import { PageTitle } from '../../layout/AppLayout';
import { cn } from '../../lib/utils';
import {
  createManagedUser,
  loadLicensePlans,
  loadOrganizations,
  loadUserSessionsPage,
  lockUser,
  terminateUserSession,
  unlockUser,
  type LicensePlan,
  type Organization,
  type UserSession
} from './operations-api';
import { formatDateTime, LoadingModal, StatusBadge, useMinimumLoading } from './operation-utils';

const emptyCreateForm = {
  email: '',
  name: '',
  password: '',
  organizationId: '',
  department: '',
  position: '',
  licenseCode: 'EDU' as 'FREE' | 'EDU' | 'PRO'
};

export function UserSessionsPage() {
  const { toast } = useToast();
  const [sessions, setSessions] = useState<UserSession[]>([]);
  const [page, setPage] = useState(1);
  const [total, setTotal] = useState(0);
  const [keyword, setKeyword] = useState('');
  const [filterValues, setFilterValues] = useState<Record<string, string>>({});
  const [organizations, setOrganizations] = useState<Organization[]>([]);
  const [licensePlans, setLicensePlans] = useState<LicensePlan[]>([]);
  const [loading, setLoading] = useState(true);
  const [failed, setFailed] = useState(false);
  const [createOpen, setCreateOpen] = useState(false);
  const [createForm, setCreateForm] = useState(emptyCreateForm);
  const [createSaving, setCreateSaving] = useState(false);
  const [menuSession, setMenuSession] = useState<{ id: string; x: number; y: number } | null>(null);
  const [detailSession, setDetailSession] = useState<UserSession | null>(null);
  const loadingVisible = useMinimumLoading(loading);

  const refresh = () => {
    setLoading(true);
    loadUserSessionsPage({ page, limit: 6, keyword, state: filterValues.state })
      .then((result) => {
        setSessions(result.items);
        setTotal(result.total);
        setFailed(false);
      })
      .catch(() => {
        setSessions([]);
        setFailed(true);
      })
      .finally(() => setLoading(false));
  };

  useEffect(() => {
    refresh();
    Promise.all([
      loadOrganizations().catch(() => []),
      loadLicensePlans().catch(() => [])
    ]).then(([nextOrganizations, nextLicensePlans]) => {
      setOrganizations(nextOrganizations);
      setLicensePlans(nextLicensePlans);
      setCreateForm((current) => ({
        ...current,
        organizationId: current.organizationId || '',
        licenseCode: (current.licenseCode || nextLicensePlans[0]?.code || 'EDU') as 'FREE' | 'EDU' | 'PRO'
      }));
    });
  }, [page, keyword, filterValues.state]);

  useEffect(() => {
    if (!menuSession) return;

    const close = () => setMenuSession(null);
    const closeOnEscape = (event: KeyboardEvent) => {
      if (event.key === 'Escape') setMenuSession(null);
    };

    window.addEventListener('click', close);
    window.addEventListener('keydown', closeOnEscape);
    return () => {
      window.removeEventListener('click', close);
      window.removeEventListener('keydown', closeOnEscape);
    };
  }, [menuSession]);

  const rows = sessions;

  const columns = useMemo<Array<DataTableColumn<UserSession>>>(
    () => [
      { key: 'no', header: 'No.', className: 'w-14 px-3 py-3 text-center font-medium', cell: (row) => <span className="block text-center font-semibold">{row.no}</span> },
      {
        key: 'user',
        header: '사용자',
        className: 'w-[280px] px-5 py-3 font-medium',
        cell: (row) => (
          <div className="flex min-w-0 items-center gap-3">
            <UserAvatar session={row} />
            <div className="min-w-0">
              <p className="truncate font-semibold">{row.user}</p>
              {row.email ? <p className="mt-1 truncate text-xs font-medium text-muted-foreground">{row.email}</p> : null}
            </div>
          </div>
        )
      },
      { key: 'session', header: '세션', className: 'w-28 px-5 py-3', cell: (row) => <span className="font-mono text-xs text-muted-foreground">{row.session}</span> },
      { key: 'expiresAt', header: '만료', className: 'w-40 px-5 py-3', cell: (row) => <span className="whitespace-nowrap text-muted-foreground">{formatDateTime(row.expiresAt)}</span> },
      { key: 'lastSeen', header: '최근 접속', className: 'w-40 px-5 py-3', cell: (row) => <span className="whitespace-nowrap text-muted-foreground">{formatDateTime(row.lastSeen)}</span> },
      { key: 'state', header: '상태', className: 'w-32 px-5 py-3', cell: (row) => <StatusBadge status={row.state} /> },
      {
        key: 'actions',
        header: '',
        className: 'w-20 px-5 py-3 text-right font-medium',
        cell: (row) => (
          <div className="relative flex justify-end">
            <Button
              variant="ghost"
              className="size-8 px-0"
              title="메뉴"
              aria-label="메뉴"
              onClick={(event) => {
                event.stopPropagation();
                const rect = event.currentTarget.getBoundingClientRect();
                setMenuSession((prev) => (prev?.id === row.id ? null : { id: row.id, x: rect.right, y: rect.bottom + 6 }));
              }}
            >
              <MoreHorizontal className="size-4" />
            </Button>
          </div>
        )
      }
    ],
    [menuSession?.id]
  );

  const filters = useMemo<Array<DataTableFilter<UserSession>>>(
    () => [
      { key: 'state', label: '상태', options: ['유효토큰', '세션 없음', '잠김', '만료', '종료'].map((state) => ({ label: state, value: state })), getValue: (row) => row.state }
    ],
    []
  );

  const openCreateModal = () => {
    setCreateForm({
      ...emptyCreateForm,
      organizationId: '',
      licenseCode: (licensePlans[0]?.code || 'EDU') as 'FREE' | 'EDU' | 'PRO'
    });
    setCreateOpen(true);
  };

  const submitCreateUser = () => {
    if (!createForm.email.trim() || !createForm.name.trim() || createForm.password.length < 8) return;

    setCreateSaving(true);
    createManagedUser({
      email: createForm.email.trim(),
      name: createForm.name.trim(),
      password: createForm.password,
      organizationId: createForm.organizationId || null,
      department: createForm.department.trim() || null,
      position: createForm.position.trim() || null,
      licenseCode: createForm.licenseCode
    })
      .then(() => {
        toast({ type: 'success', title: '사용자 등록', message: '사용자가 등록되었습니다.' });
        setCreateOpen(false);
        refresh();
      })
      .catch((error: Error) => {
        toast({ type: 'error', title: '사용자 등록 실패', message: error.message });
      })
      .finally(() => setCreateSaving(false));
  };

  return (
    <>
      <PageTitle
        eyebrow="운영"
        title="사용자/세션"
        description="사용자의 유효토큰, 만료, 종료 상태를 확인하고 필요한 제어 작업을 실행합니다."
        actions={
          <Button className="h-8 px-3 text-[13px]" onClick={openCreateModal}>
            <Plus className="size-4" />
            추가
          </Button>
        }
      />
      {failed ? (
        <div className="mb-4 rounded-md border border-rose-500/30 bg-rose-500/10 px-4 py-3 text-sm text-rose-200">
          사용자/세션 데이터를 불러오지 못했습니다.
        </div>
      ) : null}
      <DataTableCard
        title="목록"
        rows={rows}
        columns={columns}
        filters={filters}
        searchPlaceholder="사용자, 이메일, 세션 검색"
        getSearchText={(row) => `${row.user} ${row.email ?? ''} ${row.session} ${row.state}`}
        getRowKey={(row) => row.id}
        pageSize={6}
        minWidth={900}
        loading={loading}
        emptyMessage="표시할 사용자/세션 데이터가 없습니다."
        serverPagination={{
          page,
          total,
          onPageChange: setPage,
          onSearchChange: (value) => {
            setKeyword(value);
            setPage(1);
          },
          filterValues,
          onFilterChange: (key, value) => {
            setFilterValues((prev) => ({ ...prev, [key]: value }));
            setPage(1);
          }
        }}
      />
      {menuSession ? (() => {
        const row = rows.find((item) => item.id === menuSession.id);
        if (!row) return null;
        const locked = row.state === '잠김';
        return (
          <div onClick={(event) => event.stopPropagation()} className="fixed z-[70] min-w-32 overflow-hidden rounded-md border border-border bg-card py-1 text-left shadow-xl" style={{ left: menuSession.x, top: menuSession.y, transform: 'translateX(-100%)' }}>
            <button
              type="button"
              className="block w-full px-3 py-2 text-left text-xs text-foreground hover:bg-muted"
              onClick={() => {
                setMenuSession(null);
                setDetailSession(row);
              }}
            >
              상세보기
            </button>
            <button
              type="button"
              className="block w-full px-3 py-2 text-left text-xs text-foreground hover:bg-muted"
              onClick={() => {
                setMenuSession(null);
                const request = locked ? unlockUser(row.userId) : lockUser(row.userId);
                request.then(refresh).catch(() => setFailed(true));
              }}
            >
              {locked ? '잠금 해제' : '잠금'}
            </button>
            <button
              type="button"
              className="block w-full px-3 py-2 text-left text-xs text-foreground hover:bg-muted disabled:cursor-not-allowed disabled:text-muted-foreground disabled:hover:bg-transparent"
              disabled={!row.sessionId || row.state === '종료' || row.state === '만료'}
              onClick={() => {
                if (!row.sessionId) return;
                setMenuSession(null);
                terminateUserSession(row.sessionId).then(refresh).catch(() => setFailed(true));
              }}
            >
              유효토큰 종료
            </button>
          </div>
        );
      })() : null}
      <Modal
        open={Boolean(detailSession)}
        title="사용자 상세 정보"
        onClose={() => setDetailSession(null)}
        className="!max-w-2xl"
        footer={<Button variant="outline" onClick={() => setDetailSession(null)}>닫기</Button>}
      >
        {detailSession ? (
          <div className="space-y-5">
            <div className="flex min-w-0 items-start justify-between gap-4 rounded-md border border-border bg-muted/20 px-4 py-3">
              <div className="flex min-w-0 items-center gap-3">
                <UserAvatar session={detailSession} size="lg" />
                <div className="min-w-0">
                  <p className="truncate text-sm font-semibold text-foreground">{detailSession.user}</p>
                  <p className="mt-1 truncate text-xs text-muted-foreground">{detailSession.email ?? '-'}</p>
                </div>
              </div>
              <StatusBadge status={detailSession.state} />
            </div>
            <div className="grid gap-3 text-sm">
              <DetailItem label="사용자 ID" value={detailSession.userId} mono />
              <DetailItem label="조직" value={detailSession.primaryAffiliation?.organizationName ?? '-'} />
              <DetailItem label="조직 유형" value={organizationTypeLabel(detailSession.primaryAffiliation?.organizationType)} />
              <DetailItem label="부서" value={detailSession.primaryAffiliation?.department ?? '-'} />
              <DetailItem label="직책" value={detailSession.primaryAffiliation?.position ?? '-'} />
              <DetailItem label="세션 ID" value={detailSession.sessionId ?? '-'} mono />
              <DetailItem label="세션" value={detailSession.session} mono />
              <DetailItem label="상태" value={detailSession.state} />
              <DetailItem label="만료" value={formatDateTime(detailSession.expiresAt)} />
              <DetailItem label="최근 접속" value={formatDateTime(detailSession.lastSeen)} />
            </div>
          </div>
        ) : null}
      </Modal>
      <Modal
        open={createOpen}
        title="사용자 추가"
        onClose={() => {
          if (!createSaving) setCreateOpen(false);
        }}
        footer={
          <>
            <Button variant="outline" onClick={() => setCreateOpen(false)} disabled={createSaving}>취소</Button>
            <Button
              onClick={submitCreateUser}
              disabled={createSaving || !createForm.email.trim() || !createForm.name.trim() || createForm.password.length < 8}
            >
              {createSaving ? '등록 중' : '등록'}
            </Button>
          </>
        }
      >
        <div className="space-y-4">
          <label className="block">
            <span className="text-xs font-medium text-muted-foreground">이메일 <b className="text-foreground">*</b></span>
            <input
              className="mt-2 h-9 w-full rounded-md border border-input bg-background px-3 text-sm text-foreground outline-none focus:ring-2 focus:ring-ring"
              value={createForm.email}
              onChange={(event) => setCreateForm((current) => ({ ...current, email: event.target.value }))}
            />
          </label>
          <label className="block">
            <span className="text-xs font-medium text-muted-foreground">이름 <b className="text-foreground">*</b></span>
            <input
              className="mt-2 h-9 w-full rounded-md border border-input bg-background px-3 text-sm text-foreground outline-none focus:ring-2 focus:ring-ring"
              value={createForm.name}
              onChange={(event) => setCreateForm((current) => ({ ...current, name: event.target.value }))}
            />
          </label>
          <label className="block">
            <span className="text-xs font-medium text-muted-foreground">임시 비밀번호 <b className="text-foreground">*</b></span>
            <input
              type="password"
              className="mt-2 h-9 w-full rounded-md border border-input bg-background px-3 text-sm text-foreground outline-none focus:ring-2 focus:ring-ring"
              value={createForm.password}
              onChange={(event) => setCreateForm((current) => ({ ...current, password: event.target.value }))}
            />
          </label>
          <label className="block">
            <span className="text-xs font-medium text-muted-foreground">조직</span>
            <select
              className="mt-2 h-9 w-full rounded-md border border-input bg-background px-3 text-sm text-foreground outline-none focus:ring-2 focus:ring-ring"
              value={createForm.organizationId}
              onChange={(event) => setCreateForm((current) => ({ ...current, organizationId: event.target.value }))}
            >
              <option value="">없음</option>
              {organizations.map((organization) => (
                <option key={organization.id} value={organization.id}>{organization.name}</option>
              ))}
            </select>
          </label>
          <div className="grid gap-3 sm:grid-cols-2">
            <label className="block">
              <span className="text-xs font-medium text-muted-foreground">부서</span>
              <input
                className="mt-2 h-9 w-full rounded-md border border-input bg-background px-3 text-sm text-foreground outline-none focus:ring-2 focus:ring-ring"
                value={createForm.department}
                onChange={(event) => setCreateForm((current) => ({ ...current, department: event.target.value }))}
              />
            </label>
            <label className="block">
              <span className="text-xs font-medium text-muted-foreground">직책</span>
              <input
                className="mt-2 h-9 w-full rounded-md border border-input bg-background px-3 text-sm text-foreground outline-none focus:ring-2 focus:ring-ring"
                value={createForm.position}
                onChange={(event) => setCreateForm((current) => ({ ...current, position: event.target.value }))}
              />
            </label>
          </div>
          <label className="block">
            <span className="text-xs font-medium text-muted-foreground">라이센스 <b className="text-foreground">*</b></span>
            <select
              className="mt-2 h-9 w-full rounded-md border border-input bg-background px-3 text-sm text-foreground outline-none focus:ring-2 focus:ring-ring"
              value={createForm.licenseCode}
              onChange={(event) => setCreateForm((current) => ({ ...current, licenseCode: event.target.value as 'FREE' | 'EDU' | 'PRO' }))}
            >
              {licensePlans.map((plan) => (
                <option key={plan.code} value={plan.code}>{plan.name}</option>
              ))}
              {licensePlans.length === 0 ? <option value="EDU">EDU</option> : null}
            </select>
          </label>
        </div>
      </Modal>
      <LoadingModal open={loadingVisible} />
    </>
  );
}

function organizationTypeLabel(type?: string | null) {
  const labels: Record<string, string> = {
    COMPANY: '회사',
    SCHOOL: '학교',
    GOVERNMENT: '공공기관',
    LAB: '연구소',
    OTHER: '기타'
  };

  return type ? labels[type] ?? type : '-';
}

function UserAvatar({ session, size = 'sm' }: { session: UserSession; size?: 'sm' | 'lg' }) {
  const [failed, setFailed] = useState(false);
  const initial = (session.user || session.email || '?').trim().charAt(0).toUpperCase() || '?';
  const sizeClassName = size === 'lg' ? 'size-14 text-lg' : 'size-9 text-sm';

  if (session.avatarUrl && !failed) {
    return (
      <img
        src={session.avatarUrl}
        alt=""
        className={cn(sizeClassName, 'shrink-0 rounded-full border border-border bg-muted object-cover')}
        onError={() => setFailed(true)}
      />
    );
  }

  return (
    <span className={cn(sizeClassName, 'inline-flex shrink-0 items-center justify-center rounded-full border border-border bg-muted font-semibold text-muted-foreground')}>
      {initial}
    </span>
  );
}

function DetailItem({ label, value, mono = false }: { label: string; value: string; mono?: boolean }) {
  return (
    <label className="block min-w-0">
      <span className="text-xs font-medium text-muted-foreground">{label}</span>
      <div className={cn('mt-2 min-h-9 w-full rounded-md border border-input bg-background px-3 py-2 text-sm font-medium text-foreground', mono && 'break-all font-mono text-xs font-normal')}>
        {value || '-'}
      </div>
    </label>
  );
}