Course outline

import type {
  CourseLessonKind,
  CourseStatus,
} from "better-supabase/blocks/courses";
import type { LucideIcon } from "lucide-react";

import {
  AwardIcon,
  CircleCheckIcon,
  CircleIcon,
  FileTextIcon,
  ListChecksIcon,
  PlayCircleIcon,
  TriangleAlertIcon,
} from "lucide-react";
import { getExtracted } from "next-intl/server";
import { refresh } from "next/cache";

import {
  Alert,
  AlertAction,
  AlertDescription,
  AlertTitle,
} from "@/components/reui/alert";
import { Badge } from "@/components/reui/badge";
import { Button, buttonVariants } from "@/components/ui/button";
import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card";
import {
  Empty,
  EmptyContent,
  EmptyDescription,
  EmptyHeader,
  EmptyMedia,
  EmptyTitle,
} from "@/components/ui/empty";
import { Progress } from "@/components/ui/progress";
import { Skeleton } from "@/components/ui/skeleton";
import { Link } from "@/i18n/navigation";

import { getOutline } from "../courses-queries";
import { EnrollButton } from "./course-controls";

// oxlint-disable-next-line typescript/require-await -- a Server Action must be async, and refresh() returns nothing to await
async function retry() {
  "use server";
  refresh();
}

const statusVariants = {
  draft: "secondary",
  published: "success-light",
  archived: "outline",
} as const satisfies Record<CourseStatus, string>;

const kindIcons = {
  content: FileTextIcon,
  video: PlayCircleIcon,
  quiz: ListChecksIcon,
} as const satisfies Record<CourseLessonKind, LucideIcon>;

/**
 * Render inside `<Suspense>`: a course's modules, lessons and the caller's
 * progress.
 */
export async function CourseOutline({
  params,
}: {
  params: Promise<{ courseId: string }>;
}) {
  const { courseId } = await params;

  const [view, t] = await Promise.all([
    getOutline(courseId),
    getExtracted("courses"),
  ]);

  if (view.kind === "no-organization") {
    return null;
  }

  if (view.kind === "error") {
    return (
      <Alert variant="destructive" data-recipe="course-outline">
        <TriangleAlertIcon />
        <AlertTitle>{t("The course didn't load")}</AlertTitle>
        <AlertDescription>{t("Try again in a moment.")}</AlertDescription>
        <AlertAction>
          <form action={retry}>
            <Button size="sm" variant="outline" type="submit">
              {t("Retry")}
            </Button>
          </form>
        </AlertAction>
      </Alert>
    );
  }

  const course = view.data;
  const learner = course.learner;

  const statusLabels: Record<CourseStatus, string> = {
    draft: t("Draft"),
    published: t("Published"),
    archived: t("Archived"),
  };

  const kindLabels: Record<CourseLessonKind, string> = {
    content: t("Reading"),
    video: t("Video"),
    quiz: t("Quiz"),
  };

  const next = course.modules
    .flatMap((module) => module.lessons)
    .find((lesson) => !lesson.done);

  return (
    <div data-recipe="course-outline" className="flex flex-col gap-6">
      <div className="flex flex-wrap items-start justify-between gap-3">
        <div className="flex flex-col gap-1">
          <div className="flex items-center gap-2">
            <h2 className="text-lg font-semibold">{course.title}</h2>
            <Badge variant={statusVariants[course.status]}>
              {statusLabels[course.status]}
            </Badge>
          </div>
          {course.summary ? (
            <p className="text-sm text-muted-foreground">{course.summary}</p>
          ) : null}
        </div>
        {learner === null ? (
          course.status === "published" ? (
            <EnrollButton courseId={course.id} />
          ) : null
        ) : next === undefined ? null : (
          <Link
            href={`/courses/${course.id}/lessons/${next.id}`}
            className={buttonVariants()}
          >
            <PlayCircleIcon />
            {t("Continue")}
          </Link>
        )}
      </div>

      <div className="grid gap-6 lg:grid-cols-3">
        <div className="flex flex-col gap-4 lg:col-span-2">
          {course.modules.length === 0 ? (
            <Empty className="border">
              <EmptyHeader>
                <EmptyMedia variant="icon">
                  <ListChecksIcon />
                </EmptyMedia>
                <EmptyTitle>{t("No lessons yet")}</EmptyTitle>
                <EmptyDescription>
                  {t("Lessons show up here once a manager adds them.")}
                </EmptyDescription>
              </EmptyHeader>
              <EmptyContent>
                <Link
                  href="/courses"
                  className={buttonVariants({ variant: "outline" })}
                >
                  {t("All courses")}
                </Link>
              </EmptyContent>
            </Empty>
          ) : (
            course.modules.map((module) => (
              <Card key={module.id}>
                <CardHeader>
                  <CardTitle>{module.title}</CardTitle>
                  <CardDescription>
                    {t("{count, plural, one {# lesson} other {# lessons}}", {
                      count: module.lessons.length,
                    })}
                  </CardDescription>
                </CardHeader>
                <CardContent>
                  <ul className="divide-y">
                    {module.lessons.map((lesson) => {
                      const KindIcon = kindIcons[lesson.kind];

                      return (
                        <li
                          key={lesson.id}
                          className="flex items-center gap-3 py-2"
                        >
                          {lesson.done ? (
                            <CircleCheckIcon
                              className="size-4 text-success"
                              aria-label={t("Done")}
                            />
                          ) : (
                            <CircleIcon
                              className="size-4 text-muted-foreground"
                              aria-label={t("Not done")}
                            />
                          )}
                          {learner === null ? (
                            <span className="flex-1 text-sm">
                              {lesson.title}
                            </span>
                          ) : (
                            <Link
                              href={`/courses/${course.id}/lessons/${lesson.id}`}
                              className="flex-1 text-sm transition-colors hover:text-primary"
                            >
                              {lesson.title}
                            </Link>
                          )}
                          <span className="flex items-center gap-1 text-xs text-muted-foreground">
                            <KindIcon className="size-3.5" />
                            {kindLabels[lesson.kind]}
                          </span>
                          {lesson.minutes === null ? null : (
                            <span className="text-xs text-muted-foreground">
                              {t("{minutes, number} min", {
                                minutes: lesson.minutes,
                              })}
                            </span>
                          )}
                          {lesson.required ? null : (
                            <Badge variant="outline">{t("Optional")}</Badge>
                          )}
                        </li>
                      );
                    })}
                  </ul>
                </CardContent>
              </Card>
            ))
          )}
        </div>

        <Card>
          <CardHeader>
            <CardTitle>{t("Your progress")}</CardTitle>
            <CardDescription>
              {learner === null
                ? t("Enroll to track your progress.")
                : t("{done, number} of {total, number} lessons done", {
                    done: learner.completed,
                    total: learner.total,
                  })}
            </CardDescription>
          </CardHeader>
          {learner === null ? null : (
            <CardContent className="flex flex-col gap-4">
              <Progress
                value={
                  learner.total === 0
                    ? 0
                    : (learner.completed / learner.total) * 100
                }
                aria-label={t("Your progress")}
              />
              {learner.certificateCode === null ? null : (
                <div className="flex items-center gap-2 text-sm">
                  <AwardIcon className="size-4 text-success" />
                  <span>{t("Certificate")}</span>
                  <code className="text-xs text-muted-foreground">
                    {learner.certificateCode}
                  </code>
                </div>
              )}
            </CardContent>
          )}
        </Card>
      </div>
    </div>
  );
}

export function CourseOutlineSkeleton() {
  return (
    <div className="flex flex-col gap-6" aria-busy="true">
      <Skeleton className="h-8 w-64" />
      <div className="grid gap-6 lg:grid-cols-3">
        <Skeleton className="h-64 rounded-xl lg:col-span-2" />
        <Skeleton className="h-40 rounded-xl" />
      </div>
    </div>
  );
}