import { dirname } from "node:path";

export function getCallerDirname(): string {
  const e = new Error();
  if (e.stack == null) {
    Error.captureStackTrace(e);
  }
  return dirname(extractCallerPath(e.stack as string));
}

// Comprehensive regex patterns for different stack frame formats
const patterns =
  process.platform === "win32"
    ? [
        // File URLs: "at functionName (file:///C:/path/file.js:1:1)"
        /\bat\s.+?\((?<path>file:\/\/\/.+?):\d+:\d+\)$/,
        // File URLs direct: "at file:///C:/path/file.js:1:1"
        /\bat\s(?<path>file:\/\/\/.+?):\d+:\d+$/,
        // Standard: "at functionName (C:\path\file.js:1:1)"
        /\bat\s.+?\((?<path>[A-Z]:\\.+):\d+:\d+\)$/,
        // direct: "at C:\path\file.js:1:1"
        /\bat\s(?<path>[A-Z]:\\.+):\d+:\d+$/,
        // UNC: "at functionName (\\server\share\path\file.js:1:1)"
        /\bat\s.+?\((?<path>\\\\.+):\d+:\d+\)$/,
        // direct: "at \\server\share\path\file.js:1:1"
        /\bat\s(?<path>\\\\.+):\d+:\d+$/,
      ]
    : [
        // Standard: "at functionName (/path/file.js:1:1)"
        /\bat\s.+?\((?<path>\/.+?):\d+:\d+\)$/,
        // Anonymous or direct: "at /path/file.js:1:1"
        // eslint-disable-next-line security/detect-unsafe-regex -- Pattern is safe: no nested quantifiers
        /\bat\s(?:[^\s()]+\s)?(?<path>\/[^:]+):\d+:\d+$/,
      ];

const MaybeUrlRE = /^[a-z]{2,5}:\/\//i;

// only exposed for tests:
export function extractCallerPath(stack: string): string {
  const frames = stack.split("\n").filter(Boolean);

  // First find getCallerDirname() in the stack:
  const callerFrame = frames.findIndex((frame) =>
    frame.includes("getCallerDirname"),
  );
  if (callerFrame === -1) {
    throw new Error("Invalid stack trace format: missing caller frame");
  }
  for (let i = callerFrame + 1; i < frames.length; i++) {
    // eslint-disable-next-line security/detect-object-injection -- Index is from controlled for-loop
    const frame = frames[i];
    for (const pattern of patterns) {
      const g = frame?.trim().match(pattern)?.groups;
      if (g != null && g["path"]) {
        const path = g["path"];
        // Windows requires us to check if it's a reasonable URL, as URL accepts
        // "C:\\path\\file.txt" as valid (!!)
        if (MaybeUrlRE.test(path)) {
          try {
            return new URL(path).pathname;
          } catch {
            // ignore
          }
        }
        return path;
      }
    }
  }
  throw new Error("Invalid stack trace format: no parsable frames");
}