import { resolve, join, isAbsolute, sep } from "path";

/**
 * Resolve a user-supplied file path and confine it to projectRoot.
 *
 * Absolute paths are honored only if they land inside the root; relative paths
 * are joined to the root. Throws if the path escapes the root (absolute path
 * outside it, or `..` traversal) or if no root is configured. This is what keeps
 * write_file / apply_patch from writing anywhere on disk.
 */
export function resolveWithinRoot(projectRoot: string, filePath: string): string {
  if (!projectRoot || !projectRoot.trim()) {
    throw new Error(
      "No project root configured. Set projectRoot in plugin settings or pass the root parameter.",
    );
  }
  const root = resolve(projectRoot);
  const abs = resolve(isAbsolute(filePath) ? filePath : join(root, filePath));
  // Containment check: equal to root, or under root + separator. The trailing
  // separator prevents a sibling-prefix bypass (e.g. /proj vs /proj-evil).
  if (abs !== root && !abs.startsWith(root + sep)) {
    throw new Error(
      `Path escapes the project root: ${filePath}. Paths must stay within ${root}.`,
    );
  }
  return abs;
}

import { resolve, join, isAbsolute, sep } from "path";

/**
 * Resolve a user-supplied file path and confine it to projectRoot.
 *
 * Absolute paths are honored only if they land inside the root; relative paths
 * are joined to the root. Throws if the path escapes the root (absolute path
 * outside it, or `..` traversal) or if no root is configured. This is what keeps
 * write_file / apply_patch from writing anywhere on disk.
 */
export function resolveWithinRoot(projectRoot: string, filePath: string): string {
  if (!projectRoot || !projectRoot.trim()) {
    throw new Error(
      "No project root configured. Set projectRoot in plugin settings or pass the root parameter.",
    );
  }
  const root = resolve(projectRoot);
  const abs = resolve(isAbsolute(filePath) ? filePath : join(root, filePath));
  // Containment check: equal to root, or under root + separator. The trailing
  // separator prevents a sibling-prefix bypass (e.g. /proj vs /proj-evil).
  if (abs !== root && !abs.startsWith(root + sep)) {
    throw new Error(
      `Path escapes the project root: ${filePath}. Paths must stay within ${root}.`,
    );
  }
  return abs;
}