/**
 * @file app/api/servers/[serverId]/route.ts
 * @description API route handler for updating and deleting servers.
 */

import { auth } from "@/auth";
import { db } from "@/db";
import { servers } from "@/db/schema";
import { eq } from "drizzle-orm";
import { revalidatePath } from "next/cache";
import { NextResponse } from "next/server";

/** Handles PATCH requests to update an existing server's name. */
export async function PATCH(
  req: Request,
  { params }: { params: Promise<{ serverId: string }> },
) {
  try {
    const { serverId } = await params;
    const session = await auth();

    if (!session?.user?.id) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const body = await req.json().catch(() => null);
    const name = body?.name;
    const color = body?.color;

    // Ensure name is present, valid string type, and not just whitespace
    if (!name || typeof name !== "string" || !name.trim()) {
      return NextResponse.json(
        { error: "Server name is required and cannot be empty." },
        { status: 400 },
      );
    }

    const trimmedName = name.trim();

    // Ensure server name stays within allowable character limits
    if (trimmedName.length > 32) {
      return NextResponse.json(
        { error: "Server name cannot exceed 32 characters." },
        { status: 400 },
      );
    }

    // Validate color if provided
    if (color !== undefined && (typeof color !== "string" || !color.trim())) {
      return NextResponse.json(
        { error: "Invalid color value provided." },
        { status: 400 },
      );
    }

    // Check if the server exists
    const [existingServer] = await db
      .select()
      .from(servers)
      .where(eq(servers.id, serverId))
      .limit(1);

    if (!existingServer) {
      return NextResponse.json({ error: "Server not found." }, { status: 404 });
    }

    // Check if the user is the owner of the server
    if (existingServer.ownerId !== session.user.id) {
      return NextResponse.json(
        { error: "You do not have permission to edit this server." },
        { status: 403 },
      );
    }

    // Prepare fields to update
    const updateData: { name: string; color?: string } = {
      name: trimmedName,
    };

    if (color && typeof color === "string") {
      updateData.color = color.trim();
    }

    // Update Server
    const [updatedServer] = await db
      .update(servers)
      .set(updateData)
      .where(eq(servers.id, serverId))
      .returning();

    revalidatePath("/", "layout");
    return NextResponse.json(updatedServer);
  } catch (error) {
    console.error("API Server PATCH error:", error);
    return NextResponse.json(
      { error: "An unexpected internal server error occurred." },
      { status: 500 },
    );
  }
}

/** Handles DELETE requests to remove an existing server. */
export async function DELETE(
  req: Request,
  { params }: { params: Promise<{ serverId: string }> },
) {
  try {
    const { serverId } = await params;
    const session = await auth();

    if (!session?.user?.id) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    // Check if the server exists
    const [existingServer] = await db
      .select()
      .from(servers)
      .where(eq(servers.id, serverId))
      .limit(1);

    if (!existingServer) {
      return NextResponse.json({ error: "Server not found." }, { status: 404 });
    }

    // Check if the user is the owner of the server
    if (existingServer.ownerId !== session.user.id) {
      return NextResponse.json(
        { error: "You do not have permission to delete this server." },
        { status: 403 },
      );
    }

    // Delete Server
    await db.delete(servers).where(eq(servers.id, serverId));
    return NextResponse.json({ success: true });
  } catch (error) {
    console.error("API Server DELETE error:", error);
    return NextResponse.json(
      { error: "An unexpected internal server error occurred." },
      { status: 500 },
    );
  }
}