import { lstat, readdir } from "node:fs/promises";
import { join } from "node:path";
import type { WorkspaceBoundary } from "./boundary";

export interface WalkOptions {
  maxDepth: number;
  maxEntries: number;
  includeHidden?: boolean;
  ignoreNames?: string[];
}

export interface WalkEntry {
  path: string;
  type: "file" | "directory" | "symlink" | "other";
  bytes?: number;
  depth: number;
}

const DEFAULT_IGNORES = new Set(["node_modules", ".git", ".agentic"]);

export async function walkWorkspace(
  boundary: WorkspaceBoundary,
  startPath: string,
  options: WalkOptions,
): Promise<{ entries: WalkEntry[]; truncated: boolean }> {
  const entries: WalkEntry[] = [];
  const ignores = new Set([...DEFAULT_IGNORES, ...(options.ignoreNames ?? [])]);
  let truncated = false;

  const inspect = async (relativePath: string) => {
    const absolute = await boundary.resolveRead(relativePath);
    return { absolute, info: await lstat(absolute) };
  };

  const visit = async (relativeDirectory: string, depth: number): Promise<void> => {
    if (depth > options.maxDepth || truncated) return;
    // Resolve on every recursion. A directory replaced with a symlink between
    // parent enumeration and traversal is rejected by the workspace boundary.
    const { absolute, info } = await inspect(relativeDirectory);
    if (!info.isDirectory() || info.isSymbolicLink()) return;
    const children = await readdir(absolute, { withFileTypes: true });
    children.sort((a, b) => a.name.localeCompare(b.name));
    for (const child of children) {
      if (entries.length >= options.maxEntries) {
        truncated = true;
        return;
      }
      if (!options.includeHidden && child.name.startsWith(".")) continue;
      if (ignores.has(child.name)) continue;
      const childAbsolute = join(absolute, child.name);
      const current = await lstat(childAbsolute);
      const rel = boundary.relativePath(childAbsolute);
      if (current.isSymbolicLink()) {
        entries.push({ path: rel, type: "symlink", depth });
      } else if (current.isDirectory()) {
        entries.push({ path: rel, type: "directory", depth });
        await visit(rel, depth + 1);
      } else if (current.isFile()) {
        entries.push({ path: rel, type: "file", bytes: current.size, depth });
      } else {
        entries.push({ path: rel, type: "other", depth });
      }
    }
  };

  const start = await inspect(startPath);
  const startRelative = boundary.relativePath(start.absolute);
  if (start.info.isSymbolicLink()) {
    entries.push({ path: startRelative, type: "symlink", depth: 0 });
  } else if (start.info.isDirectory()) {
    await visit(startRelative, 0);
  } else {
    entries.push({
      path: startRelative,
      type: start.info.isFile() ? "file" : "other",
      ...(start.info.isFile() ? { bytes: start.info.size } : {}),
      depth: 0,
    });
  }
  return { entries, truncated };
}

import { lstat, readdir } from "node:fs/promises";
import { join } from "node:path";
import type { WorkspaceBoundary } from "./boundary";

export interface WalkOptions {
  maxDepth: number;
  maxEntries: number;
  includeHidden?: boolean;
  ignoreNames?: string[];
}

export interface WalkEntry {
  path: string;
  type: "file" | "directory" | "symlink" | "other";
  bytes?: number;
  depth: number;
}

const DEFAULT_IGNORES = new Set(["node_modules", ".git", ".agentic"]);

export async function walkWorkspace(
  boundary: WorkspaceBoundary,
  startPath: string,
  options: WalkOptions,
): Promise<{ entries: WalkEntry[]; truncated: boolean }> {
  const entries: WalkEntry[] = [];
  const ignores = new Set([...DEFAULT_IGNORES, ...(options.ignoreNames ?? [])]);
  let truncated = false;

  const inspect = async (relativePath: string) => {
    const absolute = await boundary.resolveRead(relativePath);
    return { absolute, info: await lstat(absolute) };
  };

  const visit = async (relativeDirectory: string, depth: number): Promise<void> => {
    if (depth > options.maxDepth || truncated) return;
    // Resolve on every recursion. A directory replaced with a symlink between
    // parent enumeration and traversal is rejected by the workspace boundary.
    const { absolute, info } = await inspect(relativeDirectory);
    if (!info.isDirectory() || info.isSymbolicLink()) return;
    const children = await readdir(absolute, { withFileTypes: true });
    children.sort((a, b) => a.name.localeCompare(b.name));
    for (const child of children) {
      if (entries.length >= options.maxEntries) {
        truncated = true;
        return;
      }
      if (!options.includeHidden && child.name.startsWith(".")) continue;
      if (ignores.has(child.name)) continue;
      const childAbsolute = join(absolute, child.name);
      const current = await lstat(childAbsolute);
      const rel = boundary.relativePath(childAbsolute);
      if (current.isSymbolicLink()) {
        entries.push({ path: rel, type: "symlink", depth });
      } else if (current.isDirectory()) {
        entries.push({ path: rel, type: "directory", depth });
        await visit(rel, depth + 1);
      } else if (current.isFile()) {
        entries.push({ path: rel, type: "file", bytes: current.size, depth });
      } else {
        entries.push({ path: rel, type: "other", depth });
      }
    }
  };

  const start = await inspect(startPath);
  const startRelative = boundary.relativePath(start.absolute);
  if (start.info.isSymbolicLink()) {
    entries.push({ path: startRelative, type: "symlink", depth: 0 });
  } else if (start.info.isDirectory()) {
    await visit(startRelative, 0);
  } else {
    entries.push({
      path: startRelative,
      type: start.info.isFile() ? "file" : "other",
      ...(start.info.isFile() ? { bytes: start.info.size } : {}),
      depth: 0,
    });
  }
  return { entries, truncated };
}