import { NextRequest, NextResponse } from "next/server";
import { getServerSession } from "next-auth/next";
import { authOptions } from "@/app/api/auth/options";
import { prisma } from "@/lib/prisma";

/**
 * Check if a user exists in the database
 */
async function userExists(userId: string): Promise<boolean> {
  try {
    const user = await prisma.user.findUnique({
      where: { id: userId },
      select: { id: true }
    });
    return !!user;
  } catch (error) {
    console.error(`Error checking if user exists:`, error);
    return false;
  }
}

// GET - Retrieve a specific announcement
export async function GET(
  req: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  try {
    const session = await getServerSession(authOptions);
    
    if (!session) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const { id } = await params;
    
    // Find announcement by ID
    const announcement = await prisma.announcement.findUnique({
      where: { id },
      include: {
        author: {
          select: {
            id: true,
            email: true
          }
        }
      }
    });
    
    if (!announcement) {
      return NextResponse.json({ error: "Announcement not found" }, { status: 404 });
    }
    
    // Check if user has access to this announcement
    const userRole = session.user.role || [];
    const roles = Array.isArray(userRole) ? userRole : [userRole];
    
    const hasAccess = 
      announcement.targetRoles.includes("all") || 
      announcement.targetRoles.some((role: string) => roles.includes(role));
    
    if (!hasAccess) {
      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
    }
    
    return NextResponse.json(announcement);
  } catch (error) {
    console.error("Error fetching announcement:", error);
    const errorMessage = error instanceof Error ? error.message : "Unknown error";
    return NextResponse.json({ 
      error: "Failed to fetch announcement",
      details: errorMessage
    }, { status: 500 });
  }
}

// DELETE - Remove an announcement
export async function DELETE(
  req: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  try {
    const session = await getServerSession(authOptions);
    
    if (!session) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }
    
    // Verify user exists in database
    const userExistsInDB = await userExists(session.user.id);
    
    if (!userExistsInDB) {
      console.error("User not found in database:", session.user.id);
      return NextResponse.json({ 
        error: "User not found",
        details: `The user ID from your session (${session.user.id}) doesn't exist in the database.` 
      }, { status: 400 });
    }
    
    // Check if user has admin, entrepreneurship, or communication role
    const userRole = session.user.role || [];
    const roles = Array.isArray(userRole) ? userRole : [userRole];
    const hasAdminAccess = roles.some(role => 
      ["admin", "entrepreneurship", "communication"].includes(role)
    );
    
    if (!hasAdminAccess) {
      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
    }
    
    const { id } = await params;
    
    // Check if announcement exists
    const announcement = await prisma.announcement.findUnique({
      where: { id }
    });
    
    if (!announcement) {
      return NextResponse.json({ error: "Announcement not found" }, { status: 404 });
    }
    
    // Delete the announcement
    await prisma.announcement.delete({
      where: { id }
    });
    
    return NextResponse.json({ message: "Announcement deleted successfully" });
  } catch (error) {
    console.error("Error deleting announcement:", error);
    const errorMessage = error instanceof Error ? error.message : "Unknown error";
    const errorCode = error.code || "UNKNOWN";
    
    return NextResponse.json({ 
      error: "Failed to delete announcement",
      details: errorMessage,
      code: errorCode
    }, { status: 500 });
  }
}