#!/usr/bin/env node
/**
 * run-shellcheck.mjs — shell script quality wrapper (M1, S-105)
 *
 * Discovers *.sh files under scripts/ and skills/ (excluding node_modules
 * and generated agent-variant directories), then runs shellcheck on each.
 *
 * shellcheck is a REQUIRED prerequisite.  The script fails immediately when
 * shellcheck is not found on PATH.  Install it with:
 *   macOS:  brew install shellcheck
 *   Debian: apt-get install shellcheck
 *
 * Exit codes:
 *   0  — all files passed shellcheck
 *   1  — one or more files have shellcheck findings
 *   2  — shellcheck is missing from PATH
 */

import { spawnSync } from "node:child_process";
import { readdirSync } from "node:fs";
import path from "node:path";
import { fileURLToPath } from "node:url";

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const REPO_ROOT = path.resolve(__dirname, "../..");

// ── Prerequisites check ────────────────────────────────────────────────────

function checkShellcheck() {
  const result = spawnSync("shellcheck", ["--version"], { encoding: "utf8" });
  if (result.error || result.status === null || result.status > 1) {
    console.error(
      [
        "ERROR: shellcheck is not available on PATH.",
        "",
        "shellcheck is a required prerequisite for this repository.",
        "Install it before running lint:",
        "",
        "  macOS:  brew install shellcheck",
        "  Debian/Ubuntu: sudo apt-get install shellcheck",
        "  Other:  https://github.com/koalaman/shellcheck#installing",
      ].join("\n")
    );
    process.exit(2);
  }
}

// ── File discovery ─────────────────────────────────────────────────────────

/**
 * Directories to scan for *.sh files.
 * Relative paths from REPO_ROOT.
 */
const SCAN_DIRS = ["scripts", "skills"];

/**
 * Path segments that indicate a directory should be skipped entirely.
 * Matches generated agent-variant bundles and npm/pnpm install artifacts.
 */
const SKIP_SEGMENTS = new Set([
  "node_modules",
  // Generated agent-variant directories (excluded per M1 workspace policy)
  // skills/<skill>/codex — except web-automation/codex which is canonical
  // We skip all codex variants to be safe; shellcheck only cares about .sh files
  // and all variants share the same scripts anyway.
]);

/**
 * Exact relative paths (from REPO_ROOT) to skip, matched after normalisation.
 * These are the generated variants that duplicate canonical source.
 */
const SKIP_PATHS = new Set([
  "skills/atlassian/codex",
  "skills/atlassian/claude-code",
  "skills/atlassian/cursor",
  "skills/atlassian/opencode",
  "skills/atlassian/pi",
  "skills/web-automation/claude-code",
  "skills/web-automation/cursor",
  "skills/web-automation/opencode",
  "skills/web-automation/pi",
  "pi-package",
]);

function shouldSkip(absPath) {
  const rel = path.relative(REPO_ROOT, absPath);
  // Check exact-prefix matches (directory and its children)
  for (const skip of SKIP_PATHS) {
    if (rel === skip || rel.startsWith(skip + path.sep)) return true;
  }
  // Check path-segment matches (e.g. node_modules anywhere in path)
  for (const seg of rel.split(path.sep)) {
    if (SKIP_SEGMENTS.has(seg)) return true;
  }
  return false;
}

function collectShellFiles(dir) {
  const found = [];
  let entries;
  try {
    entries = readdirSync(dir, { withFileTypes: true });
  } catch {
    return found; // directory does not exist — skip silently
  }
  for (const entry of entries) {
    const full = path.join(dir, entry.name);
    if (shouldSkip(full)) continue;
    if (entry.isDirectory()) {
      found.push(...collectShellFiles(full));
    } else if (entry.isFile() && entry.name.endsWith(".sh")) {
      found.push(full);
    }
  }
  return found;
}

// ── Main ───────────────────────────────────────────────────────────────────

checkShellcheck();

const files = SCAN_DIRS.flatMap((d) =>
  collectShellFiles(path.join(REPO_ROOT, d))
);

if (files.length === 0) {
  console.log("shellcheck: no .sh files found — nothing to check.");
  process.exit(0);
}

console.log(`shellcheck: scanning ${files.length} file(s)…`);

let failures = 0;
for (const file of files.sort()) {
  const result = spawnSync("shellcheck", ["-x", "--source-path=SCRIPTDIR", file], {
    encoding: "utf8",
    stdio: ["ignore", "pipe", "pipe"],
  });
  const output = (result.stdout + result.stderr).trim();
  const rel = path.relative(REPO_ROOT, file);
  if (result.status !== 0) {
    failures += 1;
    // Print findings prefixed with the relative path so output is reproducible
    // regardless of cwd.
    console.error(`\n--- ${rel} ---`);
    if (output) console.error(output);
  } else {
    // Quiet on success — only show problems
  }
}

if (failures > 0) {
  console.error(
    `\nshellcheck: ${failures} file(s) have findings. ` +
      `See docs/CLEANUP-BASELINE.md for the as-is baseline.`
  );
  process.exit(1);
} else {
  console.log("shellcheck: all files passed.");
  process.exit(0);
}