import Link from 'next/link';

import {
  GraduationCap,
  Users,
  Calendar,
  Euro,
  User,
  Clock,
  Pencil,
} from 'lucide-react';
import { getTranslations } from 'next-intl/server';

import { createCourseManagementApi } from '@kit/course-management/api';
import { formatDate, formatCurrencyAmount } from '@kit/shared/dates';
import { getSupabaseServerClient } from '@kit/supabase/server-client';
import { Badge } from '@kit/ui/badge';
import { Button } from '@kit/ui/button';
import { Card, CardContent, CardHeader, CardTitle } from '@kit/ui/card';

import { AccountNotFound } from '~/components/account-not-found';
import { CmsPageShell } from '~/components/cms-page-shell';
import {
  COURSE_STATUS_VARIANT,
  COURSE_STATUS_LABEL_KEYS,
} from '~/lib/status-badges';

import { CreateSessionDialog } from './create-session-dialog';
import { DeleteCourseButton } from './delete-course-button';

interface PageProps {
  params: Promise<{ account: string; courseId: string }>;
}

export default async function CourseDetailPage({ params }: PageProps) {
  const { account, courseId } = await params;
  const client = getSupabaseServerClient();
  const api = createCourseManagementApi(client);
  const t = await getTranslations('courses');

  const [course, participants, sessions] = await Promise.all([
    api.courses.getById(courseId),
    api.enrollment.listParticipants(courseId),
    api.sessions.list(courseId),
  ]);

  if (!course) return <AccountNotFound />;

  const courseData = course as Record<string, unknown>;

  return (
    <CmsPageShell account={account} title={String(courseData.name)}>
      <div className="flex w-full flex-col gap-6">
        {/* Action Buttons */}
        <div className="flex justify-end gap-2">
          <Button asChild variant="outline" size="sm">
            <Link href={`/home/${account}/courses/${courseId}/edit`}>
              <Pencil className="mr-2 h-4 w-4" />
              {t('detail.edit')}
            </Link>
          </Button>
          <DeleteCourseButton courseId={courseId} accountSlug={account} />
        </div>

        {/* Summary Cards */}
        <div className="grid grid-cols-1 gap-4 sm:grid-cols-2 lg:grid-cols-3">
          <Card>
            <CardContent className="flex items-center gap-3 p-4">
              <GraduationCap className="text-primary h-5 w-5" />
              <div>
                <p className="text-muted-foreground text-xs">
                  {t('detail.name')}
                </p>
                <p className="font-semibold">{String(courseData.name)}</p>
              </div>
            </CardContent>
          </Card>
          <Card>
            <CardContent className="flex items-center gap-3 p-4">
              <Clock className="text-primary h-5 w-5" />
              <div>
                <p className="text-muted-foreground text-xs">
                  {t('common.status')}
                </p>
                <Badge
                  variant={
                    COURSE_STATUS_VARIANT[String(courseData.status)] ??
                    'secondary'
                  }
                >
                  {t(
                    COURSE_STATUS_LABEL_KEYS[String(courseData.status)] ??
                      String(courseData.status),
                  )}
                </Badge>
              </div>
            </CardContent>
          </Card>
          <Card>
            <CardContent className="flex items-center gap-3 p-4">
              <User className="text-primary h-5 w-5" />
              <div>
                <p className="text-muted-foreground text-xs">
                  {t('detail.instructor')}
                </p>
                <p className="font-semibold">
                  {String(courseData.instructor_id ?? '—')}
                </p>
              </div>
            </CardContent>
          </Card>
          <Card>
            <CardContent className="flex items-center gap-3 p-4">
              <Calendar className="text-primary h-5 w-5" />
              <div>
                <p className="text-muted-foreground text-xs">
                  {t('detail.dateRange')}
                </p>
                <p className="font-semibold">
                  {formatDate(courseData.start_date as string)}
                  {' – '}
                  {formatDate(courseData.end_date as string)}
                </p>
              </div>
            </CardContent>
          </Card>
          <Card>
            <CardContent className="flex items-center gap-3 p-4">
              <Euro className="text-primary h-5 w-5" />
              <div>
                <p className="text-muted-foreground text-xs">{t('list.fee')}</p>
                <p className="font-semibold">
                  {courseData.fee != null
                    ? formatCurrencyAmount(courseData.fee as number)
                    : '—'}
                </p>
              </div>
            </CardContent>
          </Card>
          <Card>
            <CardContent className="flex items-center gap-3 p-4">
              <Users className="text-primary h-5 w-5" />
              <div>
                <p className="text-muted-foreground text-xs">
                  {t('detail.participants')}
                </p>
                <p className="font-semibold">
                  {participants.length} / {String(courseData.capacity ?? '∞')}
                </p>
              </div>
            </CardContent>
          </Card>
        </div>

        {/* Participants Section */}
        <Card>
          <CardHeader className="flex flex-row items-center justify-between">
            <CardTitle>{t('detail.participants')}</CardTitle>
            <Button variant="outline" size="sm" asChild>
              <Link href={`/home/${account}/courses/${courseId}/participants`}>
                {t('detail.viewAll')}
              </Link>
            </Button>
          </CardHeader>
          <CardContent>
            <div className="overflow-x-auto rounded-md border">
              <table className="w-full min-w-[640px] text-sm">
                <thead>
                  <tr className="bg-muted/50 border-b">
                    <th scope="col" className="p-3 text-left font-medium">
                      {t('detail.name')}
                    </th>
                    <th scope="col" className="p-3 text-left font-medium">
                      {t('detail.email')}
                    </th>
                    <th scope="col" className="p-3 text-left font-medium">
                      {t('common.status')}
                    </th>
                    <th scope="col" className="p-3 text-left font-medium">
                      {t('detail.date')}
                    </th>
                  </tr>
                </thead>
                <tbody>
                  {participants.length === 0 ? (
                    <tr>
                      <td
                        colSpan={4}
                        className="text-muted-foreground p-6 text-center"
                      >
                        {t('detail.noParticipants')}
                      </td>
                    </tr>
                  ) : (
                    participants.map((p: Record<string, unknown>) => (
                      <tr
                        key={String(p.id)}
                        className="hover:bg-muted/30 border-b"
                      >
                        <td className="p-3 font-medium">
                          {String(p.last_name ?? '')},{' '}
                          {String(p.first_name ?? '')}
                        </td>
                        <td className="p-3">{String(p.email ?? '—')}</td>
                        <td className="p-3">
                          <Badge variant="outline">
                            {String(p.status ?? '—')}
                          </Badge>
                        </td>
                        <td className="p-3">
                          {formatDate(p.enrolled_at as string)}
                        </td>
                      </tr>
                    ))
                  )}
                </tbody>
              </table>
            </div>
          </CardContent>
        </Card>

        {/* Sessions Section */}
        <Card>
          <CardHeader className="flex flex-row items-center justify-between">
            <CardTitle>{t('detail.sessions')}</CardTitle>
            <div className="flex gap-2">
              <CreateSessionDialog courseId={courseId} />
              <Button variant="outline" size="sm" asChild>
                <Link href={`/home/${account}/courses/${courseId}/attendance`}>
                  {t('detail.attendance')}
                </Link>
              </Button>
            </div>
          </CardHeader>
          <CardContent>
            <div className="overflow-x-auto rounded-md border">
              <table className="w-full min-w-[640px] text-sm">
                <thead>
                  <tr className="bg-muted/50 border-b">
                    <th scope="col" className="p-3 text-left font-medium">
                      {t('detail.date')}
                    </th>
                    <th scope="col" className="p-3 text-left font-medium">
                      {t('list.startDate')}
                    </th>
                    <th scope="col" className="p-3 text-left font-medium">
                      {t('list.endDate')}
                    </th>
                    <th scope="col" className="p-3 text-left font-medium">
                      {t('detail.cancelled')}
                    </th>
                  </tr>
                </thead>
                <tbody>
                  {sessions.length === 0 ? (
                    <tr>
                      <td
                        colSpan={4}
                        className="text-muted-foreground p-6 text-center"
                      >
                        {t('detail.noSessions')}
                      </td>
                    </tr>
                  ) : (
                    sessions.map((s: Record<string, unknown>) => (
                      <tr
                        key={String(s.id)}
                        className="hover:bg-muted/30 border-b"
                      >
                        <td className="p-3">
                          {formatDate(s.session_date as string)}
                        </td>
                        <td className="p-3">{String(s.start_time ?? '—')}</td>
                        <td className="p-3">{String(s.end_time ?? '—')}</td>
                        <td className="p-3">
                          {s.cancelled ? (
                            <Badge variant="destructive">
                              {t('common.yes')}
                            </Badge>
                          ) : (
                            '—'
                          )}
                        </td>
                      </tr>
                    ))
                  )}
                </tbody>
              </table>
            </div>
          </CardContent>
        </Card>
      </div>
    </CmsPageShell>
  );
}