/**
 * Open Artifact Audit — Cross-type unresolved state scanner
 *
 * Scans all .planning/ artifact categories for items with open/unresolved state.
 * Returns structured JSON for workflow consumption.
 * Called by: gsd-tools.cjs audit-open
 * Used by: /gsd:complete-milestone pre-close gate
 *
 * ADR-457 build-at-publish: the hand-written bin/lib/audit.cjs collapsed
 * to a TypeScript source of truth. Behaviour is preserved byte-for-behaviour
 * from the prior hand-written .cjs; only strict types are added.
 */

import fs from 'node:fs';
import path from 'node:path';
import { platformReadSync } from './shell-command-projection.cjs';
import { collectSection } from './markdown-sectionizer.cjs';
// eslint-disable-next-line @typescript-eslint/no-require-imports
import planningWorkspace = require('./planning-workspace.cjs');
const { planningDir } = planningWorkspace;
// eslint-disable-next-line @typescript-eslint/no-require-imports
import frontmatter = require('./frontmatter.cjs');
const { extractFrontmatter } = frontmatter;
// eslint-disable-next-line @typescript-eslint/no-require-imports
import phaseIdMod = require('./phase-id.cjs');
const { PHASE_NUMBER_TOKEN_SOURCE } = phaseIdMod;
import { requireSafePath, sanitizeForDisplay } from './security.cjs';

// ─── Types ────────────────────────────────────────────────────────────────────

interface DebugSessionItem {
  slug: string;
  status: string;
  updated: string;
  hypothesis: string;
  scan_error?: boolean;
}

interface QuickTaskItem {
  slug: string;
  date: string;
  status: string;
  description: string;
  scan_error?: boolean;
}

interface ThreadItem {
  slug: string;
  status: string;
  updated: string;
  title: string;
  scan_error?: boolean;
}

interface TodoItem {
  filename: string;
  priority: string;
  area: string;
  summary: string;
  scan_error?: boolean;
  _remainder_count?: number;
}

interface SeedItem {
  seed_id: string;
  slug: string;
  status: string;
  title: string;
  scan_error?: boolean;
}

interface UatGapItem {
  phase: string;
  file: string;
  status: string;
  open_scenario_count: number;
  scan_error?: boolean;
}

interface VerificationGapItem {
  phase: string;
  file: string;
  status: string;
  scan_error?: boolean;
}

interface ContextQuestionItem {
  phase: string;
  file: string;
  question_count: number;
  questions: string[];
  scan_error?: boolean;
}

interface DeferredItem {
  phase: string;
  file: string;
  text: string;
  scan_error?: boolean;
}

/**
 * Minimal structural view of `uat.cjs` — only the export `scanDeferredItems`
 * lazily requires. Mirrors the local-interface convention in
 * `audit-command-router.cts`, which types its lazy requires the same way.
 */
interface UatDeferredModule {
  parseDeferredItems(content: string): Array<{ name: string }>;
}

interface AuditCounts {
  debug_sessions: number;
  quick_tasks: number;
  threads: number;
  todos: number;
  seeds: number;
  uat_gaps: number;
  verification_gaps: number;
  context_questions: number;
  deferred_items: number;
  total: number;
}

interface AuditResult {
  scanned_at: string;
  has_open_items: boolean;
  counts: AuditCounts;
  items: {
    debug_sessions: DebugSessionItem[];
    quick_tasks: QuickTaskItem[];
    threads: ThreadItem[];
    todos: TodoItem[];
    seeds: SeedItem[];
    uat_gaps: UatGapItem[];
    verification_gaps: VerificationGapItem[];
    context_questions: ContextQuestionItem[];
    deferred_items: DeferredItem[];
  };
}

// The SCOPE BOUNDARY convention's filename (`agents/gsd-executor.md`), shared
// verbatim with the #2287 phase-boundary reader in `uat.cts`.
const DEFERRED_ITEMS_FILENAME = 'deferred-items.md';

// Terminal UAT states: `complete` (legacy) and `resolved` (post-gap-closure
// per workflows/execute-phase.md). Hoisted outside scanUatGaps so the Set is
// not recreated on each loop iteration.
const TERMINAL_UAT_STATUSES = new Set(['complete', 'resolved']);

// ─── scanDebugSessions ────────────────────────────────────────────────────────

/**
 * Scan .planning/debug/ for open sessions.
 * Open = status NOT in ['resolved', 'complete'].
 * Ignores the resolved/ subdirectory.
 */
function scanDebugSessions(planDir: string): DebugSessionItem[] {
  const debugDir = path.join(planDir, 'debug');
  if (!fs.existsSync(debugDir)) return [];

  const results: DebugSessionItem[] = [];
  let files: fs.Dirent[];
  try {
    files = fs.readdirSync(debugDir, { withFileTypes: true });
  } catch {
    return [{ scan_error: true, slug: '', status: '', updated: '', hypothesis: '' }];
  }

  for (const entry of files) {
    if (!entry.isFile()) continue;
    if (!entry.name.endsWith('.md')) continue;

    const filePath = path.join(debugDir, entry.name);

    let safeFilePath: string;
    try {
      safeFilePath = requireSafePath(filePath, planDir, 'debug session file', { allowAbsolute: true });
    } catch {
      continue;
    }

    const content = platformReadSync(safeFilePath);
    if (content === null) continue;

    const fm = extractFrontmatter(content, safeFilePath);
    const status = ((fm.status as string) || 'unknown').toLowerCase();
    if (status === 'resolved' || status === 'complete') continue;

    // Extract hypothesis from "Current Focus" block if parseable
    let hypothesis = '';
    const focusSection = collectSection(content, (h) => h.level === 2 && h.text.trim().toLowerCase().startsWith('current focus'), { levelBounded: true });
    if (focusSection) {
      const focusText = focusSection.body.trim().split('\n')[0].trim();
      hypothesis = sanitizeForDisplay(focusText.slice(0, 100));
    }

    const slug = path.basename(entry.name, '.md');
    results.push({
      slug: sanitizeForDisplay(slug),
      status: sanitizeForDisplay(status),
      updated: sanitizeForDisplay(fm.updated || fm.date || ''),
      hypothesis,
    });
  }

  return results;
}

// ─── scanQuickTasks ───────────────────────────────────────────────────────────

/**
 * Scan .planning/quick/ for incomplete tasks.
 * Incomplete if SUMMARY.md missing or status !== 'complete'.
 */
function scanQuickTasks(planDir: string): QuickTaskItem[] {
  const quickDir = path.join(planDir, 'quick');
  if (!fs.existsSync(quickDir)) return [];

  let entries: fs.Dirent[];
  try {
    entries = fs.readdirSync(quickDir, { withFileTypes: true });
  } catch {
    return [{ scan_error: true, slug: '', date: '', status: '', description: '' }];
  }

  const results: QuickTaskItem[] = [];
  for (const entry of entries) {
    if (!entry.isDirectory()) continue;

    const dirName = entry.name;
    const taskDir = path.join(quickDir, dirName);

    let safeTaskDir: string;
    try {
      safeTaskDir = requireSafePath(taskDir, planDir, 'quick task dir', { allowAbsolute: true });
    } catch {
      continue;
    }

    // workflows/quick.md mandates `${quick_id}-SUMMARY.md`; older flows used
    // bare `SUMMARY.md`. Accept either to avoid false-positive "missing".
    //
    // #3183 (ADR-3180 Decision 4(a) — bucket B, out of scope for the
    // scanPhasePlans migration): this scans a quick task's OWN directory
    // (`.planning/quick/<task>/`) for THAT task's single completion record —
    // "does this one quick task have a SUMMARY.md" — not a phase directory's
    // live-plan/summary counting question. scanPhasePlans is the wrong tool
    // here; there is no plan/summary PAIRING to derive, only a single
    // filename presence check local to a non-phase directory.
    let summaryPath: string | null = null;
    try {
      const summaryFiles = fs.readdirSync(safeTaskDir, { withFileTypes: true })
        .filter(e => e.isFile() && (e.name === 'SUMMARY.md' || e.name.endsWith('-SUMMARY.md')));
      if (summaryFiles.length > 0) {
        // Prefer the per-task `${quick_id}-SUMMARY.md` form when present.
        const preferred = summaryFiles.find(e => e.name === `${dirName}-SUMMARY.md`)
          || summaryFiles.find(e => e.name.endsWith('-SUMMARY.md'))
          || summaryFiles[0];
        summaryPath = path.join(safeTaskDir, preferred.name);
      }
    } catch {
      // fall through with summaryPath = null → status: missing
    }

    let status = 'missing';
    const description = '';

    if (summaryPath && fs.existsSync(summaryPath)) {
      let safeSum: string;
      try {
        safeSum = requireSafePath(summaryPath, planDir, 'quick task summary', { allowAbsolute: true });
      } catch {
        continue;
      }
      const content = platformReadSync(safeSum);
      if (content === null) {
        status = 'unreadable';
      } else {
        const fm = extractFrontmatter(content, safeSum);
        status = ((fm.status as string) || 'unknown').toLowerCase();
      }
    }

    if (status === 'complete') continue;

    // Parse date and slug from directory name: YYYYMMDD-slug or YYYY-MM-DD-slug
    let date = '';
    let slug = sanitizeForDisplay(dirName);
    const dateMatch = dirName.match(/^(\d{4}-?\d{2}-?\d{2})-(.+)$/);
    if (dateMatch) {
      date = dateMatch[1];
      slug = sanitizeForDisplay(dateMatch[2]);
    }

    results.push({
      slug,
      date,
      status: sanitizeForDisplay(status),
      description,
    });
  }

  return results;
}

// ─── scanThreads ──────────────────────────────────────────────────────────────

/**
 * Scan .planning/threads/ for open threads.
 * Open if status in ['open', 'in_progress', 'in progress'] (case-insensitive).
 */
function scanThreads(planDir: string): ThreadItem[] {
  const threadsDir = path.join(planDir, 'threads');
  if (!fs.existsSync(threadsDir)) return [];

  let files: fs.Dirent[];
  try {
    files = fs.readdirSync(threadsDir, { withFileTypes: true });
  } catch {
    return [{ scan_error: true, slug: '', status: '', updated: '', title: '' }];
  }

  const openStatuses = new Set(['open', 'in_progress', 'in progress']);
  const results: ThreadItem[] = [];

  for (const entry of files) {
    if (!entry.isFile()) continue;
    if (!entry.name.endsWith('.md')) continue;

    const filePath = path.join(threadsDir, entry.name);

    let safeFilePath: string;
    try {
      safeFilePath = requireSafePath(filePath, planDir, 'thread file', { allowAbsolute: true });
    } catch {
      continue;
    }

    const content = platformReadSync(safeFilePath);
    if (content === null) continue;

    const fm = extractFrontmatter(content, safeFilePath);
    let status = ((fm.status as string) || '').toLowerCase().trim();

    // Fall back to scanning body for ## Status: OPEN / IN PROGRESS
    if (!status) {
      const bodyStatusMatch = content.match(/##\s*Status:\s*(OPEN|IN PROGRESS|IN_PROGRESS)/i);
      if (bodyStatusMatch) {
        status = bodyStatusMatch[1].toLowerCase().replace(/ /g, '_');
      }
    }

    if (!openStatuses.has(status)) continue;

    // Extract title from # Thread: heading or frontmatter title
    let title = sanitizeForDisplay(fm.title || '');
    if (!title) {
      const headingMatch = content.match(/^#\s*Thread:\s*(.+)$/m);
      if (headingMatch) {
        title = sanitizeForDisplay(headingMatch[1].trim().slice(0, 100));
      }
    }

    const slug = path.basename(entry.name, '.md');
    results.push({
      slug: sanitizeForDisplay(slug),
      status: sanitizeForDisplay(status),
      updated: sanitizeForDisplay(fm.updated || fm.date || ''),
      title,
    });
  }

  return results;
}

// ─── scanTodos ────────────────────────────────────────────────────────────────

/**
 * Scan .planning/todos/pending/ for pending todos.
 * Returns array of { filename, priority, area, summary }.
 * Display limited to first 5 + count of remainder.
 */
function scanTodos(planDir: string): TodoItem[] {
  const pendingDir = path.join(planDir, 'todos', 'pending');
  if (!fs.existsSync(pendingDir)) return [];

  let files: fs.Dirent[];
  try {
    files = fs.readdirSync(pendingDir, { withFileTypes: true });
  } catch {
    return [{ scan_error: true, filename: '', priority: '', area: '', summary: '' }];
  }

  const mdFiles = files.filter(e => e.isFile() && e.name.endsWith('.md'));
  const results: TodoItem[] = [];

  const displayFiles = mdFiles.slice(0, 5);
  for (const entry of displayFiles) {
    const filePath = path.join(pendingDir, entry.name);

    let safeFilePath: string;
    try {
      safeFilePath = requireSafePath(filePath, planDir, 'todo file', { allowAbsolute: true });
    } catch {
      continue;
    }

    const content = platformReadSync(safeFilePath);
    if (content === null) continue;

    const fm = extractFrontmatter(content, safeFilePath);

    // Extract first line of body after frontmatter
    const bodyMatch = content.replace(/^---[\s\S]*?---\n?/, '');
    const firstLine = bodyMatch.trim().split('\n')[0] || '';
    const summary = sanitizeForDisplay(firstLine.slice(0, 100));

    results.push({
      filename: sanitizeForDisplay(entry.name),
      priority: sanitizeForDisplay(fm.priority || ''),
      area: sanitizeForDisplay(fm.area || ''),
      summary,
    });
  }

  if (mdFiles.length > 5) {
    results.push({ _remainder_count: mdFiles.length - 5, filename: '', priority: '', area: '', summary: '' });
  }

  return results;
}

// ─── scanSeeds ────────────────────────────────────────────────────────────────

/**
 * Scan .planning/seeds/SEED-*.md for unimplemented seeds.
 * Unimplemented if status in ['dormant', 'active', 'triggered'].
 */
function scanSeeds(planDir: string): SeedItem[] {
  const seedsDir = path.join(planDir, 'seeds');
  if (!fs.existsSync(seedsDir)) return [];

  let files: fs.Dirent[];
  try {
    files = fs.readdirSync(seedsDir, { withFileTypes: true });
  } catch {
    return [{ scan_error: true, seed_id: '', slug: '', status: '', title: '' }];
  }

  const unimplementedStatuses = new Set(['dormant', 'active', 'triggered']);
  const results: SeedItem[] = [];

  for (const entry of files) {
    if (!entry.isFile()) continue;
    if (!entry.name.startsWith('SEED-') || !entry.name.endsWith('.md')) continue;

    const filePath = path.join(seedsDir, entry.name);

    let safeFilePath: string;
    try {
      safeFilePath = requireSafePath(filePath, planDir, 'seed file', { allowAbsolute: true });
    } catch {
      continue;
    }

    const content = platformReadSync(safeFilePath);
    if (content === null) continue;

    const fm = extractFrontmatter(content, safeFilePath);
    const status = ((fm.status as string) || 'dormant').toLowerCase();

    if (!unimplementedStatuses.has(status)) continue;

    // Extract seed_id from filename or frontmatter
    const seedIdMatch = entry.name.match(/^(SEED-[\w-]+)\.md$/);
    const seed_id = seedIdMatch ? seedIdMatch[1] : path.basename(entry.name, '.md');
    const slug = sanitizeForDisplay(seed_id.replace(/^SEED-/, ''));

    let title = sanitizeForDisplay(fm.title || '');
    if (!title) {
      const headingMatch = content.match(/^#\s*(.+)$/m);
      if (headingMatch) title = sanitizeForDisplay(headingMatch[1].trim().slice(0, 100));
    }

    results.push({
      seed_id: sanitizeForDisplay(seed_id),
      slug,
      status: sanitizeForDisplay(status),
      title,
    });
  }

  return results;
}

// ─── scanUatGaps ──────────────────────────────────────────────────────────────

/**
 * Scan .planning/phases for UAT gaps (UAT files with status != 'complete').
 */
function scanUatGaps(planDir: string): UatGapItem[] {
  const phasesDir = path.join(planDir, 'phases');
  if (!fs.existsSync(phasesDir)) return [];

  let dirs: string[];
  try {
    dirs = fs.readdirSync(phasesDir, { withFileTypes: true })
      .filter(e => e.isDirectory())
      .map(e => e.name)
      .sort();
  } catch {
    return [{ scan_error: true, phase: '', file: '', status: '', open_scenario_count: 0 }];
  }

  const results: UatGapItem[] = [];

  for (const dir of dirs) {
    const phaseDir = path.join(phasesDir, dir);
    const phaseMatch = dir.match(new RegExp(`^(${PHASE_NUMBER_TOKEN_SOURCE})`, 'i'));
    const phaseNum = phaseMatch ? phaseMatch[1] : dir;

    let files: string[];
    try {
      files = fs.readdirSync(phaseDir);
    } catch {
      continue;
    }

    for (const file of files.filter(f => f.includes('-UAT') && f.endsWith('.md'))) {
      const filePath = path.join(phaseDir, file);

      let safeFilePath: string;
      try {
        safeFilePath = requireSafePath(filePath, planDir, 'UAT file', { allowAbsolute: true });
      } catch {
        continue;
      }

      const content = platformReadSync(safeFilePath);
      if (content === null) continue;

      const fm = extractFrontmatter(content, safeFilePath);
      const status = ((fm.status as string) || 'unknown').toLowerCase();
      const result = ((fm.result as string) || '').toLowerCase();

      // Also accept `result: all_pass` as a fallback when status is absent
      // — covers UATs that omit `status:`.
      if (TERMINAL_UAT_STATUSES.has(status)) continue;
      if (status === 'unknown' && result === 'all_pass') continue;

      // Count open scenarios
      const pendingMatches = (content.match(/result:\s*(?:pending|\[pending\])/gi) || []).length;

      results.push({
        phase: sanitizeForDisplay(phaseNum),
        file: sanitizeForDisplay(file),
        status: sanitizeForDisplay(status),
        open_scenario_count: pendingMatches,
      });
    }
  }

  return results;
}

// ─── scanVerificationGaps ─────────────────────────────────────────────────────

/**
 * Scan .planning/phases for VERIFICATION gaps.
 */
function scanVerificationGaps(planDir: string): VerificationGapItem[] {
  const phasesDir = path.join(planDir, 'phases');
  if (!fs.existsSync(phasesDir)) return [];

  let dirs: string[];
  try {
    dirs = fs.readdirSync(phasesDir, { withFileTypes: true })
      .filter(e => e.isDirectory())
      .map(e => e.name)
      .sort();
  } catch {
    return [{ scan_error: true, phase: '', file: '', status: '' }];
  }

  const results: VerificationGapItem[] = [];

  for (const dir of dirs) {
    const phaseDir = path.join(phasesDir, dir);
    const phaseMatch = dir.match(new RegExp(`^(${PHASE_NUMBER_TOKEN_SOURCE})`, 'i'));
    const phaseNum = phaseMatch ? phaseMatch[1] : dir;

    let files: string[];
    try {
      files = fs.readdirSync(phaseDir);
    } catch {
      continue;
    }

    for (const file of files.filter(f => f.includes('-VERIFICATION') && f.endsWith('.md'))) {
      const filePath = path.join(phaseDir, file);

      let safeFilePath: string;
      try {
        safeFilePath = requireSafePath(filePath, planDir, 'VERIFICATION file', { allowAbsolute: true });
      } catch {
        continue;
      }

      const content = platformReadSync(safeFilePath);
      if (content === null) continue;

      const fm = extractFrontmatter(content, safeFilePath);
      const status = ((fm.status as string) || 'unknown').toLowerCase();

      if (status !== 'gaps_found' && status !== 'human_needed') continue;

      results.push({
        phase: sanitizeForDisplay(phaseNum),
        file: sanitizeForDisplay(file),
        status: sanitizeForDisplay(status),
      });
    }
  }

  return results;
}

// ─── scanContextQuestions ─────────────────────────────────────────────────────

/**
 * Scan .planning/phases for CONTEXT files with open_questions.
 */
function scanContextQuestions(planDir: string): ContextQuestionItem[] {
  const phasesDir = path.join(planDir, 'phases');
  if (!fs.existsSync(phasesDir)) return [];

  let dirs: string[];
  try {
    dirs = fs.readdirSync(phasesDir, { withFileTypes: true })
      .filter(e => e.isDirectory())
      .map(e => e.name)
      .sort();
  } catch {
    return [{ scan_error: true, phase: '', file: '', question_count: 0, questions: [] }];
  }

  const results: ContextQuestionItem[] = [];

  for (const dir of dirs) {
    const phaseDir = path.join(phasesDir, dir);
    const phaseMatch = dir.match(new RegExp(`^(${PHASE_NUMBER_TOKEN_SOURCE})`, 'i'));
    const phaseNum = phaseMatch ? phaseMatch[1] : dir;

    let files: string[];
    try {
      files = fs.readdirSync(phaseDir);
    } catch {
      continue;
    }

    for (const file of files.filter(f => f.includes('-CONTEXT') && f.endsWith('.md'))) {
      const filePath = path.join(phaseDir, file);

      let safeFilePath: string;
      try {
        safeFilePath = requireSafePath(filePath, planDir, 'CONTEXT file', { allowAbsolute: true });
      } catch {
        continue;
      }

      const content = platformReadSync(safeFilePath);
      if (content === null) continue;

      const fm = extractFrontmatter(content, safeFilePath);

      // Check frontmatter open_questions field
      let questions: string[] = [];
      if (fm.open_questions) {
        if (Array.isArray(fm.open_questions) && fm.open_questions.length > 0) {
          questions = (fm.open_questions as unknown[]).map(q => sanitizeForDisplay(String(q).slice(0, 200)));
        }
      }

      // Also check for ## Open Questions section in body
      if (questions.length === 0) {
        const oqSection = collectSection(content, (h) => h.level === 2 && h.text.trim().toLowerCase().startsWith('open questions'), { levelBounded: true });
        if (oqSection) {
          const oqBody = oqSection.body.trim();
          if (oqBody && oqBody.length > 0 && !/^\s*none\s*$/i.test(oqBody)) {
            const items = oqBody.split('\n')
              .map((l: string) => l.trim())
              .filter((l: string) => l && l !== '-' && l !== '*')
              .filter((l: string) => /^[-*\d]/.test(l) || l.includes('?'));
            questions = items.slice(0, 3).map((q: string) => sanitizeForDisplay(q.slice(0, 200)));
          }
        }
      }

      if (questions.length === 0) continue;

      results.push({
        phase: sanitizeForDisplay(phaseNum),
        file: sanitizeForDisplay(file),
        question_count: questions.length,
        questions: questions.slice(0, 3),
      });
    }
  }

  return results;
}

// ─── scanDeferredItems ────────────────────────────────────────────────────────

/**
 * Scan phase directories for UNRESOLVED entries in `deferred-items.md` (#2646).
 *
 * The SCOPE BOUNDARY convention (`agents/gsd-executor.md`) has a phase agent
 * log an out-of-scope discovery here rather than fix it. #2287 made that file
 * readable at the PHASE boundary (`/gsd-progress` check 7, `audit-uat`); this
 * scanner closes the remaining reader gap one boundary up, so an entry still
 * unresolved at MILESTONE close surfaces in the pre-close audit alongside the
 * other eight categories and the existing `[R]/[A]/[C]` prompt applies to it.
 * Without this, phase directories archive to `milestones/vX.Y-phases/` (#1871)
 * and the entry leaves the live tree having never been triaged.
 *
 * The resolved/unresolved predicate is NOT reimplemented here: `uat.cjs`
 * already exports `parseDeferredItems`, which owns the parsing rule (entries
 * under a `## Deferred Items` level-2 heading, else the whole file fail-safe;
 * RESOLVED only on an explicit case-insensitive `status: resolved` field).
 * Duplicating that inequality is how two readers of the same file drift into
 * disagreeing about what "open" means. The require is deliberately LAZY,
 * inside the scan, to preserve `audit-command-router.cts`'s property that a
 * route never loads the module it does not need.
 */
function scanDeferredItems(planDir: string): DeferredItem[] {
  const phasesDir = path.join(planDir, 'phases');
  if (!fs.existsSync(phasesDir)) return [];

  let dirs: string[];
  try {
    dirs = fs.readdirSync(phasesDir, { withFileTypes: true })
      .filter(e => e.isDirectory())
      .map(e => e.name)
      .sort();
  } catch {
    return [{ scan_error: true, phase: '', file: '', text: '' }];
  }

  // eslint-disable-next-line @typescript-eslint/no-require-imports, @typescript-eslint/no-unsafe-assignment
  const uat: UatDeferredModule = require('./uat.cjs');

  const results: DeferredItem[] = [];

  for (const dir of dirs) {
    const phaseDir = path.join(phasesDir, dir);
    const phaseMatch = dir.match(new RegExp(`^(${PHASE_NUMBER_TOKEN_SOURCE})`, 'i'));
    const phaseNum = phaseMatch ? phaseMatch[1] : dir;

    const filePath = path.join(phaseDir, DEFERRED_ITEMS_FILENAME);
    if (!fs.existsSync(filePath)) continue;

    let safeFilePath: string;
    try {
      safeFilePath = requireSafePath(filePath, planDir, 'deferred items file', { allowAbsolute: true });
    } catch {
      continue;
    }

    const content = platformReadSync(safeFilePath);
    if (content === null) continue;

    for (const item of uat.parseDeferredItems(content)) {
      results.push({
        phase: sanitizeForDisplay(phaseNum),
        file: DEFERRED_ITEMS_FILENAME,
        text: sanitizeForDisplay(item.name),
      });
    }
  }

  return results;
}

// ─── auditOpenArtifacts ───────────────────────────────────────────────────────

/**
 * Main audit function. Scans all .planning/ artifact categories.
 *
 * @param cwd - Project root directory
 * @returns Structured audit result
 */
function auditOpenArtifacts(cwd: string): AuditResult {
  const planDir = planningDir(cwd);

  const debugSessions = (() => {
    try { return scanDebugSessions(planDir); } catch { return [{ scan_error: true, slug: '', status: '', updated: '', hypothesis: '' }]; }
  })();

  const quickTasks = (() => {
    try { return scanQuickTasks(planDir); } catch { return [{ scan_error: true, slug: '', date: '', status: '', description: '' }]; }
  })();

  const threads = (() => {
    try { return scanThreads(planDir); } catch { return [{ scan_error: true, slug: '', status: '', updated: '', title: '' }]; }
  })();

  const todos = (() => {
    try { return scanTodos(planDir); } catch { return [{ scan_error: true, filename: '', priority: '', area: '', summary: '' }]; }
  })();

  const seeds = (() => {
    try { return scanSeeds(planDir); } catch { return [{ scan_error: true, seed_id: '', slug: '', status: '', title: '' }]; }
  })();

  const uatGaps = (() => {
    try { return scanUatGaps(planDir); } catch { return [{ scan_error: true, phase: '', file: '', status: '', open_scenario_count: 0 }]; }
  })();

  const verificationGaps = (() => {
    try { return scanVerificationGaps(planDir); } catch { return [{ scan_error: true, phase: '', file: '', status: '' }]; }
  })();

  const contextQuestions = (() => {
    try { return scanContextQuestions(planDir); } catch { return [{ scan_error: true, phase: '', file: '', question_count: 0, questions: [] }]; }
  })();

  const deferredItems = (() => {
    try { return scanDeferredItems(planDir); } catch { return [{ scan_error: true, phase: '', file: '', text: '' }]; }
  })();

  // Count real items (not scan_error sentinels)
  const countReal = (arr: Array<{ scan_error?: boolean; _remainder_count?: number }>) =>
    arr.filter(i => !i.scan_error && !i._remainder_count).length;

  const counts: AuditCounts = {
    debug_sessions: countReal(debugSessions),
    quick_tasks: countReal(quickTasks),
    threads: countReal(threads),
    todos: countReal(todos),
    seeds: countReal(seeds),
    uat_gaps: countReal(uatGaps),
    verification_gaps: countReal(verificationGaps),
    context_questions: countReal(contextQuestions),
    deferred_items: countReal(deferredItems),
    total: 0,
  };
  counts.total = counts.debug_sessions + counts.quick_tasks + counts.threads + counts.todos + counts.seeds + counts.uat_gaps + counts.verification_gaps + counts.context_questions + counts.deferred_items;

  return {
    scanned_at: new Date().toISOString(),
    has_open_items: counts.total > 0,
    counts,
    items: {
      debug_sessions: debugSessions,
      quick_tasks: quickTasks,
      threads,
      todos,
      seeds,
      uat_gaps: uatGaps,
      verification_gaps: verificationGaps,
      context_questions: contextQuestions,
      deferred_items: deferredItems,
    },
  };
}

// ─── formatAuditReport ────────────────────────────────────────────────────────

/**
 * Format the audit result as a human-readable report.
 *
 * @param auditResult - Result from auditOpenArtifacts()
 * @returns Formatted report
 */
function formatAuditReport(auditResult: AuditResult): string {
  const { counts, items, has_open_items } = auditResult;
  const lines: string[] = [];
  const hr = '━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━';

  lines.push(hr);
  lines.push('  Milestone Close: Open Artifact Audit');
  lines.push(hr);

  if (!has_open_items) {
    lines.push('');
    lines.push('  All artifact types clear. Safe to proceed.');
    lines.push('');
    lines.push(hr);
    return lines.join('\n');
  }

  // Debug sessions (blocking quality — red)
  if (counts.debug_sessions > 0) {
    lines.push('');
    lines.push(`🔴 Debug Sessions (${counts.debug_sessions} open)`);
    for (const item of items.debug_sessions.filter(i => !i.scan_error)) {
      const hyp = item.hypothesis ? ` — ${item.hypothesis}` : '';
      lines.push(`   • ${item.slug} [${item.status}]${hyp}`);
    }
  }

  // UAT gaps (blocking quality — red)
  if (counts.uat_gaps > 0) {
    lines.push('');
    lines.push(`🔴 UAT Gaps (${counts.uat_gaps} phases with incomplete UAT)`);
    for (const item of items.uat_gaps.filter(i => !i.scan_error)) {
      lines.push(`   • Phase ${item.phase}: ${item.file} [${item.status}] — ${item.open_scenario_count} pending scenarios`);
    }
  }

  // Verification gaps (blocking quality — red)
  if (counts.verification_gaps > 0) {
    lines.push('');
    lines.push(`🔴 Verification Gaps (${counts.verification_gaps} unresolved)`);
    for (const item of items.verification_gaps.filter(i => !i.scan_error)) {
      lines.push(`   • Phase ${item.phase}: ${item.file} [${item.status}]`);
    }
  }

  // Quick tasks (incomplete work — yellow)
  if (counts.quick_tasks > 0) {
    lines.push('');
    lines.push(`🟡 Quick Tasks (${counts.quick_tasks} incomplete)`);
    for (const item of items.quick_tasks.filter(i => !i.scan_error)) {
      const d = item.date ? ` (${item.date})` : '';
      lines.push(`   • ${item.slug}${d} [${item.status}]`);
    }
  }

  // Todos (incomplete work — yellow)
  if (counts.todos > 0) {
    const realTodos = items.todos.filter(i => !i.scan_error && !i._remainder_count);
    const remainder = items.todos.find(i => i._remainder_count);
    lines.push('');
    lines.push(`🟡 Pending Todos (${counts.todos} pending)`);
    for (const item of realTodos) {
      const area = item.area ? ` [${item.area}]` : '';
      const pri = item.priority ? ` (${item.priority})` : '';
      lines.push(`   • ${item.filename}${area}${pri}`);
      if (item.summary) lines.push(`     ${item.summary}`);
    }
    if (remainder) {
      lines.push(`   ... and ${remainder._remainder_count} more`);
    }
  }

  // Threads (deferred decisions — blue)
  if (counts.threads > 0) {
    lines.push('');
    lines.push(`🔵 Open Threads (${counts.threads} active)`);
    for (const item of items.threads.filter(i => !i.scan_error)) {
      const title = item.title ? ` — ${item.title}` : '';
      lines.push(`   • ${item.slug} [${item.status}]${title}`);
    }
  }

  // Seeds (deferred decisions — blue)
  if (counts.seeds > 0) {
    lines.push('');
    lines.push(`🔵 Unimplemented Seeds (${counts.seeds} pending)`);
    for (const item of items.seeds.filter(i => !i.scan_error)) {
      const title = item.title ? ` — ${item.title}` : '';
      lines.push(`   • ${item.seed_id} [${item.status}]${title}`);
    }
  }

  // Context questions (deferred decisions — blue)
  if (counts.context_questions > 0) {
    lines.push('');
    lines.push(`🔵 CONTEXT Open Questions (${counts.context_questions} phases with open questions)`);
    for (const item of items.context_questions.filter(i => !i.scan_error)) {
      lines.push(`   • Phase ${item.phase}: ${item.file} (${item.question_count} question${item.question_count !== 1 ? 's' : ''})`);
      for (const q of item.questions) {
        lines.push(`     - ${q}`);
      }
    }
  }

  // Deferred items (deferred decisions — blue). Out-of-scope discoveries a
  // phase agent recorded rather than fixed, still unresolved at close (#2646).
  if (counts.deferred_items > 0) {
    lines.push('');
    lines.push(`🔵 Deferred Items (${counts.deferred_items} unresolved)`);
    for (const item of items.deferred_items.filter(i => !i.scan_error)) {
      lines.push(`   • Phase ${item.phase}: ${item.text}`);
    }
  }

  lines.push('');
  lines.push(hr);
  lines.push(`  ${counts.total} item${counts.total !== 1 ? 's' : ''} require decisions before close.`);
  lines.push(hr);

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

export = { auditOpenArtifacts, formatAuditReport };