/**
 * Shared HTTP server utilities for route handlers.
 * Owner: T-1.5
 */

import type { IncomingMessage, ServerResponse } from "node:http";

/** Read the full request body as a string. */
export function readBody(req: IncomingMessage): Promise<string> {
  return new Promise((resolve, reject) => {
    const chunks: Buffer[] = [];
    req.on("data", (chunk: Buffer) => chunks.push(chunk));
    req.on("end", () => resolve(Buffer.concat(chunks).toString("utf8")));
    req.on("error", reject);
  });
}

/** Send a JSON response. */
export function sendJson(
  res: ServerResponse,
  status: number,
  body: unknown,
): void {
  const payload = JSON.stringify(body);
  res.writeHead(status, {
    "Content-Type": "application/json",
    "Content-Length": Buffer.byteLength(payload),
  });
  res.end(payload);
}

/** Extract a path segment by index (0-based, after splitting on '/'). */
export function pathSegment(url: string, index: number): string | undefined {
  return url.split("?")[0].split("/").filter(Boolean)[index];
}

/**
 * Parse bearer token from Authorization header or ?token= query param.
 * Returns the raw token string or null.
 */
export function extractBearer(req: IncomingMessage): string | null {
  const auth = req.headers["authorization"];
  if (auth?.startsWith("Bearer ")) return auth.slice(7).trim();
  if (auth?.startsWith("bearer ")) return auth.slice(7).trim();
  const url = new URL(req.url ?? "/", "http://localhost");
  return url.searchParams.get("token");
}