import { NextResponse } from "next/server";
import { prisma } from "@/lib/prisma";
import { canManageTournament } from "@/lib/permissions";

export async function POST(
  request: Request,
  { params }: { params: { id: string } }
) {
  try {
    const tournamentId = parseInt(params.id, 10);
    
    if (isNaN(tournamentId)) {
      return NextResponse.json(
        { error: "Invalid tournament ID" },
        { status: 400 }
      );
    }
    
    const body = await request.json();
    const { playerIds } = body;

    if (!playerIds || !Array.isArray(playerIds)) {
      return NextResponse.json(
        { error: "playerIds array is required" },
        { status: 400 }
      );
    }

    // Check permissions
    const permission = await canManageTournament(tournamentId);
    if (!permission.allowed) {
      return NextResponse.json(
        { error: permission.reason || 'Insufficient permissions' },
        { status: 403 }
      );
    }

    // Add participants to tournament
    const participants = await Promise.all(
      playerIds.map(async (playerId: number) => {
        try {
          // Check if participant already exists
          const existing = await prisma.eventParticipant.findFirst({
            where: {
              eventId: tournamentId,
              playerId: playerId,
            },
          });

          if (existing) {
            return existing;
          }

          // Create new participant
          return await prisma.eventParticipant.create({
            data: {
              eventId: tournamentId,
              playerId: playerId,
              status: "registered",
              registrationDate: new Date(),
            },
          });
        } catch (error) {
          console.error(`Failed to add participant ${playerId}:`, error);
          return null;
        }
      })
    );

    const successfulParticipants = participants.filter(p => p !== null);

    return NextResponse.json({
      success: true,
      added: successfulParticipants.length,
      participants: successfulParticipants,
    });
  } catch (error) {
    console.error("Failed to add participants:", error);
    return NextResponse.json(
      { error: "Failed to add participants" },
      { status: 500 }
    );
  }
}