// app/api/videos/[id]/route.ts
import { NextResponse } from "next/server";
import { prisma } from "../../../../lib/prisma";
import { getServerSession } from "next-auth";
import { authOptions } from "../../../../lib/auth-options";
import { getVideoUrls } from "../../../../lib/video-urls";

export async function GET(req: Request, context: any) {
  try {
    // unwrap params
    let params = context?.params;
    if (typeof params?.then === "function") params = await params;

    const id = params?.id;
    if (!id) return NextResponse.json({ error: "Missing video id" }, { status: 400 });

    const session = await getServerSession(authOptions);
    if (!session?.user?.email) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const user = await prisma.user.findUnique({
      where: { email: session.user.email },
      include: {
        enrollments: true,
      },
    });
    if (!user) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const video = await prisma.video.findUnique({
      where: { id },
      include: {
        playlist: {
          include: {
            course: true,
            courses: true,
          },
        },
        uploader: {
          select: {
            id: true,
            name: true,
            image: true,
          },
        },
        videoCourses: true,
      },
    });
    if (!video) return NextResponse.json({ error: "Not found" }, { status: 404 });

    const userCourseIds = user.enrollments.map((enrollment) => enrollment.courseId);

    const playlistCourseIds = new Set<string>([video.playlist.courseId]);
    (video.playlist.courses || []).forEach((mapping) => {
      playlistCourseIds.add(mapping.courseId);
    });

    const hasPlaylistAccess = [...playlistCourseIds].some((courseId) =>
      userCourseIds.includes(courseId)
    );
    if (!hasPlaylistAccess) {
      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
    }

    const restrictedCourseIds = (video.videoCourses || [])
      .filter((assignment) => assignment.exclusive)
      .map((assignment) => assignment.courseId);
    if (
      restrictedCourseIds.length > 0 &&
      !restrictedCourseIds.some((courseId) => userCourseIds.includes(courseId))
    ) {
      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
    }

    // Find the next video (index = current.index + 1)
    const next = await prisma.video.findFirst({
      where: {
        playlistId: video.playlistId,
        index: video.index + 1,
      },
      include: {
        uploader: {
          select: {
            id: true,
            name: true,
            image: true,
          },
        },
      },
    });

    // Add video URLs with HLS support
    const videoUrls = getVideoUrls(video.id, video.url, video.transcodingStatus as any);
    const responseVideo = {
      ...video,
      videoUrls,
      transcodingStatus: video.transcodingStatus,
      restrictedCourseIds,
    };

    // Ensure we return the URL field explicitly (player expects `video.url`).
    return NextResponse.json({ video: responseVideo, next });
  } catch (err: any) {
    console.error("GET /api/videos/[id] error:", err);
    return NextResponse.json({ error: "Server error" }, { status: 500 });
  }
}