#!/usr/bin/env node

/**
 * Config-Audit Self-Audit
 * Runs the plugin's own scanners on its own configuration.
 * CLI: node self-audit.mjs [--json] [--fix]
 * Exit codes: 0=PASS (no critical/high), 1=WARN (high findings), 2=FAIL (critical findings)
 * Zero external dependencies.
 */

import { resolve, dirname, join } from 'node:path';
import { fileURLToPath } from 'node:url';
import { readdir, readFile, stat } from 'node:fs/promises';
import { execFile } from 'node:child_process';
import { promisify } from 'node:util';
import { runAllScanners } from './scan-orchestrator.mjs';
import { scan as scanPluginHealth } from './plugin-health-scanner.mjs';
import { scoreByArea } from './lib/scoring.mjs';
import { gradeFromPassRate } from './lib/severity.mjs';
import { loadSuppressions, applySuppressions } from './lib/suppression.mjs';
import { parseJson } from './lib/yaml-parser.mjs';
import { humanizeEnvelope, humanizeFindings } from './lib/humanizer.mjs';

const execFileAsync = promisify(execFile);

const __dirname = dirname(fileURLToPath(import.meta.url));
const PLUGIN_ROOT = resolve(__dirname, '..');

// Scanner-shape detection: files in scanners/ that export `scan` and are not
// support modules. Matches the detection rule from v5 plan Step 16.
//
// `plugin-health-scanner.mjs` is excluded from the main scanner count: it has
// `export async function scan` but it runs standalone (not via scan-orchestrator)
// and is documented under "Standalone Scanner" in README/CLAUDE.md. The badge
// `scanners-12` reflects the orchestrated scanners that contribute to posture
// scoring.
const SCANNER_EXCLUDES = new Set([
  'scan-orchestrator.mjs',
  'self-audit.mjs',
  'whats-active.mjs',
  'plugin-health-scanner.mjs',
]);

function isScannerShape(name, content) {
  if (!name.endsWith('.mjs')) return false;
  if (SCANNER_EXCLUDES.has(name)) return false;
  if (/-cli\.mjs$/.test(name)) return false;
  if (/-engine\.mjs$/.test(name)) return false;
  return /export\s+async\s+function\s+scan\b/.test(content);
}

async function safeListDir(path) {
  try { return await readdir(path, { withFileTypes: true }); } catch { return []; }
}

async function countScannerShape(scannersDir) {
  let count = 0;
  for (const e of await safeListDir(scannersDir)) {
    if (!e.isFile()) continue;
    if (!e.name.endsWith('.mjs')) continue;
    let content = '';
    try { content = await readFile(join(scannersDir, e.name), 'utf-8'); } catch { continue; }
    if (isScannerShape(e.name, content)) count++;
  }
  return count;
}

async function countMdFiles(dir) {
  let count = 0;
  for (const e of await safeListDir(dir)) {
    if (e.isFile() && e.name.endsWith('.md')) count++;
  }
  return count;
}

async function countTestFiles(testsRoot) {
  let count = 0;
  async function walk(dir) {
    for (const e of await safeListDir(dir)) {
      const full = join(dir, e.name);
      if (e.isDirectory()) await walk(full);
      else if (e.isFile() && e.name.endsWith('.test.mjs')) count++;
    }
  }
  await walk(testsRoot);
  return count;
}

// Run the test suite in a subprocess and parse the `ℹ tests N` line emitted
// by node:test. Used for badge accuracy under --check-readme. Slow (~15s on
// the full plugin) but produces the canonical case count rather than an
// approximation. Returns null on failure so the caller can fall back to
// file count without crashing the audit.
async function countTestCases(pluginRoot) {
  try {
    const { stdout } = await execFileAsync(
      process.execPath,
      ['--test', 'tests/**/*.test.mjs'],
      { cwd: pluginRoot, timeout: 60000, maxBuffer: 10 * 1024 * 1024 },
    );
    const match = stdout.match(/^[^\n]*tests\s+(\d+)\s*$/m);
    return match ? Number(match[1]) : null;
  } catch (err) {
    // node --test exits non-zero when tests fail; the count line is still
    // present on stdout. Re-parse it from the captured output.
    const stdout = err?.stdout || '';
    const match = stdout.match(/^[^\n]*tests\s+(\d+)\s*$/m);
    return match ? Number(match[1]) : null;
  }
}

async function countHookEntries(hooksJsonPath) {
  let content;
  try { content = await readFile(hooksJsonPath, 'utf-8'); } catch { return 0; }
  const parsed = parseJson(content);
  const hooks = parsed?.hooks || parsed;
  if (!hooks || typeof hooks !== 'object' || Array.isArray(hooks)) return 0;
  let n = 0;
  for (const handlers of Object.values(hooks)) {
    if (!Array.isArray(handlers)) continue;
    for (const group of handlers) {
      if (!Array.isArray(group?.hooks)) continue;
      n += group.hooks.length;
    }
  }
  return n;
}

/**
 * Parse a numeric badge value from a README badge URL via line-anchored
 * substring detection. Returns null if no badge for `kind` is found.
 * Pattern: `badge/<kind>-<NUMBER>(+)?-<color>` — case-insensitive.
 */
function parseBadgeNumber(readme, kind) {
  const lines = readme.split('\n');
  const rx = new RegExp(`badge\\/${kind}-([0-9]+)\\+?-`, 'i');
  for (const line of lines) {
    const m = line.match(rx);
    if (m) return Number(m[1]);
  }
  return null;
}

/**
 * Compare README badge counts against filesystem-measured counts (v5 F6).
 * Filesystem counts are the source of truth.
 *
 * @param {string} pluginDir
 * @returns {Promise<{passed: boolean, mismatches: Array<{kind:string, expected:number, foundInReadme:number}>, counts: object, badges: object}>}
 */
export async function checkReadmeBadges(pluginDir) {
  const testCases = await countTestCases(pluginDir);
  const counts = {
    scanners: await countScannerShape(join(pluginDir, 'scanners')),
    commands: await countMdFiles(join(pluginDir, 'commands')),
    agents:   await countMdFiles(join(pluginDir, 'agents')),
    hooks:    await countHookEntries(join(pluginDir, 'hooks', 'hooks.json')),
    tests:    testCases ?? await countTestFiles(join(pluginDir, 'tests')),
    knowledge: await countMdFiles(join(pluginDir, 'knowledge')),
  };
  let readme = '';
  try { readme = await readFile(join(pluginDir, 'README.md'), 'utf-8'); } catch { /* missing */ }
  const badges = {
    scanners:  parseBadgeNumber(readme, 'scanners'),
    commands:  parseBadgeNumber(readme, 'commands'),
    agents:    parseBadgeNumber(readme, 'agents'),
    hooks:     parseBadgeNumber(readme, 'hooks'),
    tests:     parseBadgeNumber(readme, 'tests'),
    knowledge: parseBadgeNumber(readme, 'knowledge'),
  };
  const mismatches = [];
  for (const kind of Object.keys(counts)) {
    if (badges[kind] === null) continue; // no badge for this kind — silent
    if (counts[kind] !== badges[kind]) {
      mismatches.push({ kind, expected: counts[kind], foundInReadme: badges[kind] });
    }
  }
  return { passed: mismatches.length === 0, mismatches, counts, badges };
}

/**
 * Run self-audit on this plugin.
 * @param {object} [opts]
 * @param {boolean} [opts.fix=false] - Run fix-engine on auto-fixable findings
 * @param {boolean} [opts.checkReadme=false] - Verify README badge counts (v5 F6)
 * @returns {Promise<object>} Combined result
 */
export async function runSelfAudit(opts = {}) {
  const pluginDir = PLUGIN_ROOT;

  // 1. Run all config scanners on plugin root
  // Fixture filtering is handled automatically by runAllScanners (filterFixtures defaults to true)
  const configEnvelope = await runAllScanners(pluginDir);

  // 2. Run plugin health scanner + apply suppressions
  const pluginHealthResult = await scanPluginHealth(pluginDir);
  const { suppressions } = await loadSuppressions(pluginDir);
  if (suppressions.length > 0) {
    const { active, suppressed } = applySuppressions(pluginHealthResult.findings, suppressions);
    pluginHealthResult.findings = active;
    pluginHealthResult.suppressedFindings = suppressed;
  }

  // 3. Score config quality
  const areaScores = scoreByArea(configEnvelope.scanners);
  const avgScore = areaScores.areas.length > 0
    ? Math.round(areaScores.areas.reduce((s, a) => s + a.score, 0) / areaScores.areas.length)
    : 0;
  const configGrade = gradeFromPassRate(avgScore);

  // 4. Score plugin health
  const pluginIssueCount = pluginHealthResult.findings.length;
  const pluginScore = Math.max(0, 100 - pluginIssueCount * 10);
  const pluginGrade = gradeFromPassRate(pluginScore);

  // 5. Determine overall result
  const allFindings = [
    ...configEnvelope.scanners.flatMap(s => s.findings),
    ...pluginHealthResult.findings,
  ];

  const hasCritical = allFindings.some(f => f.severity === 'critical');
  const hasHigh = allFindings.some(f => f.severity === 'high');
  let exitCode = 0;
  let verdict = 'PASS';
  if (hasCritical) { exitCode = 2; verdict = 'FAIL'; }
  else if (hasHigh) { exitCode = 1; verdict = 'WARN'; }

  // 6. Optionally fix
  let fixResult = null;
  if (opts.fix && allFindings.some(f => f.autoFixable)) {
    try {
      const { planFixes, applyFixes } = await import('./fix-engine.mjs');
      const plan = planFixes(configEnvelope);
      if (plan.length > 0) {
        fixResult = await applyFixes(plan);
      }
    } catch {
      // Fix engine unavailable or failed — non-fatal
    }
  }

  // 7. Optional README badge check (v5 F6)
  let readmeCheck;
  if (opts.checkReadme) {
    readmeCheck = await checkReadmeBadges(pluginDir);
  }

  const out = {
    pluginDir,
    configGrade,
    configScore: avgScore,
    pluginGrade,
    pluginScore,
    configEnvelope,
    pluginHealthResult,
    allFindings,
    exitCode,
    verdict,
    fixResult,
  };
  if (readmeCheck) out.readmeCheck = readmeCheck;
  return out;
}

/**
 * Format self-audit result for terminal display.
 * @param {object} result - From runSelfAudit()
 * @returns {string}
 */
export function formatSelfAudit(result) {
  // Humanize findings for terminal-output path only. JSON path (--json) is
  // unaffected \u2014 it serializes the original `result` object directly.
  const humanizedConfigEnv = humanizeEnvelope(result.configEnvelope);
  const humanizedAllFindings = [
    ...humanizedConfigEnv.scanners.flatMap(s => s.findings),
    ...humanizeFindings(result.pluginHealthResult.findings),
  ];

  const lines = [];
  lines.push('\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501');
  lines.push(' Config-Audit Self-Audit');
  lines.push('\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501');
  lines.push('');
  lines.push(` Plugin health: ${result.pluginGrade} (${result.pluginScore})`);
  lines.push(` Config quality: ${result.configGrade} (${result.configScore})`);
  lines.push('');

  // Issues summary
  const nonInfo = humanizedAllFindings.filter(f => f.severity !== 'info');
  if (nonInfo.length > 0) {
    lines.push(` Issues (${nonInfo.length}):`);
    for (const f of nonInfo.slice(0, 10)) {
      lines.push(`  - [${f.severity}] ${f.title}`);
    }
    if (nonInfo.length > 10) {
      lines.push(`  ...and ${nonInfo.length - 10} more`);
    }
  } else {
    lines.push(' Issues (0)');
  }

  lines.push('');

  // Fix results
  if (result.fixResult) {
    const applied = result.fixResult.filter(r => r.status === 'applied').length;
    lines.push(` Auto-fix: ${applied} fix(es) applied`);
    lines.push('');
  }

  // Verdict
  if (result.verdict === 'PASS') {
    lines.push(' Self-audit: PASS');
    lines.push(' (No critical or high findings)');
  } else if (result.verdict === 'WARN') {
    lines.push(' Self-audit: WARN');
    lines.push(' (High-severity findings detected)');
  } else {
    lines.push(' Self-audit: FAIL');
    lines.push(' (Critical findings detected)');
  }

  lines.push('');
  lines.push('\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501');

  return lines.join('\n');
}

// --- CLI entry point ---
async function main() {
  const args = process.argv.slice(2);
  const jsonMode = args.includes('--json');
  const fixMode = args.includes('--fix');
  const checkReadmeMode = args.includes('--check-readme');

  const result = await runSelfAudit({ fix: fixMode, checkReadme: checkReadmeMode });

  if (jsonMode) {
    const json = JSON.stringify(result, null, 2) + '\n';
    await new Promise(resolve => process.stdout.write(json, resolve));
  } else {
    process.stderr.write('\n' + formatSelfAudit(result) + '\n');
  }

  process.exitCode = result.exitCode;
}

const isDirectRun = process.argv[1] && resolve(process.argv[1]) === resolve(fileURLToPath(import.meta.url));
if (isDirectRun) {
  main().catch(err => {
    process.stderr.write(`Fatal: ${err.message}\n`);
    process.exit(3);
  });
}