#!/usr/bin/env node
/**
 * tools/graphify-safe-update.mjs
 *
 * Safe post-commit graphify update wrapper.
 *
 * Per ADR-017 § "Стратегия обновлений" — direct `graphify update .` from
 * широкого scope разнесло граф 6305 → 41586 узлов (38 МБ bloat). Этот
 * wrapper:
 *
 *   1. Reads last commit changed files via `git diff HEAD~1 --name-only`.
 *   2. Filters to ONLY allowed scopes: docs/, .claude/, app/ — НЕ tools/,
 *      vendor/, node_modules/, bin/, .git/, etc.
 *   3. For CODE files in app/ (PHP/Vue/TS/JS) → invokes graphify AST extract
 *      on EXPLICIT file list (bypasses detect_incremental + manifest-prune
 *      risk) + build_merge into existing graph.json.
 *   4. For DOC/MD files (docs/ + .claude/ md) → writes `needs_update` flag,
 *      NO automatic LLM extraction (subagent dispatch too expensive for hook).
 *   5. Skips silently if graphify-out/ missing (e.g., worktree без graph).
 *
 * Non-blocking by design — always exits 0 to не ломать commit. Log goes to
 * stdout (lefthook собирает).
 *
 * Security Guidance #40: pure deterministic — git read + Python exec, без LLM.
 *
 * @author graphify-formalization 2026-05-27
 * @see docs/adr/ADR-017-knowledge-graph-tooling.md § "Стратегия обновлений"
 */

import { execFileSync } from 'node:child_process';
import { existsSync, writeFileSync, readFileSync } from 'node:fs';
import { join, resolve, extname } from 'node:path';

const ALLOWED_SCOPES = ['docs/', '.claude/', 'app/'];
const CODE_EXTS = new Set(['.php', '.ts', '.js', '.vue', '.mjs', '.cjs', '.py', '.go']);
const SCAN_EXCLUDE_DIRS = ['node_modules/', 'vendor/', '__pycache__/', '.git/'];

/**
 * Pure: filter a list of git-diff file paths down to those within allowed
 * scopes AND not inside excluded directories.
 *
 * @param {string[]} paths   git-diff output lines (relative repo paths)
 * @param {string[]} allowed prefixes that the path must start with
 * @param {string[]} excluded substrings that disqualify a path even if it matches a scope
 * @returns {string[]}
 */
export function filterInScope(paths, allowed, excluded) {
  return paths.filter((p) => {
    if (!allowed.some((s) => p.startsWith(s))) return false;
    if (excluded.some((ex) => p.includes(ex))) return false;
    return true;
  });
}

/**
 * Pure: partition file list by extension into code-files vs everything-else.
 * Case-insensitive on extension.
 *
 * @param {string[]} paths
 * @param {Set<string>} codeExts lowercase extensions including the dot (e.g. '.php')
 * @returns {{ codeFiles: string[], docFiles: string[] }}
 */
export function partitionByExtension(paths, codeExts) {
  const codeFiles = [];
  const docFiles = [];
  for (const p of paths) {
    const ext = extname(p).toLowerCase();
    if (codeExts.has(ext)) codeFiles.push(p);
    else docFiles.push(p);
  }
  return { codeFiles, docFiles };
}

// ────────────────────────── CLI entry ──────────────────────────
// Skip side-effects when imported as a module (tests). Works on Windows
// (file:///C:/…) and POSIX (file:///home/…) by comparing the file URL
// pathname to the resolved argv[1].
import { fileURLToPath } from 'node:url';
const isMain = process.argv[1] && fileURLToPath(import.meta.url) === resolve(process.argv[1]);

if (isMain) {
  await runCli();
}

async function runCli() {
  const REPO_ROOT = resolve(process.cwd());
  const GRAPH_DIR = join(REPO_ROOT, 'graphify-out');

  const logInfo = (msg) => process.stdout.write(`[graphify-safe-update] ${msg}\n`);
  const silentExit = (reason) => {
    if (process.env.GRAPHIFY_SAFE_DEBUG) logInfo(`silent exit: ${reason}`);
    process.exit(0);
  };

  // 1. Graph must exist
  if (!existsSync(join(GRAPH_DIR, 'graph.json'))) {
    silentExit('graphify-out/graph.json missing');
  }

  // 2. Get files changed in the LAST commit only (HEAD vs HEAD~1) — NOT
  //    `git diff HEAD~1` (1-arg) which diffs prev-commit-vs-working-tree and
  //    pollutes scope with unstaged WIP from parallel sessions. Use
  //    diff-tree of HEAD to get exactly the files touched by HEAD.
  let changedRaw;
  try {
    changedRaw = execFileSync('git', ['diff-tree', '--no-commit-id', '--name-only', '-r', 'HEAD'], {
      encoding: 'utf-8',
      stdio: ['ignore', 'pipe', 'pipe'],
    });
  } catch (e) {
    silentExit(`git diff-tree failed: ${e.message?.slice(0, 80)}`);
  }

  const allChanged = changedRaw.split('\n').map((s) => s.trim()).filter(Boolean);
  if (allChanged.length === 0) silentExit('no changed files');

  // 3. Filter to allowed scopes + exclude system dirs
  const inScope = filterInScope(allChanged, ALLOWED_SCOPES, SCAN_EXCLUDE_DIRS);
  if (inScope.length === 0) {
    silentExit(`${allChanged.length} files changed, 0 in allowed scope (docs/.claude/app)`);
  }

  // 4. Partition by code vs doc/md
  const { codeFiles, docFiles } = partitionByExtension(inScope, CODE_EXTS);

  // 5. Doc/MD files → just write needs_update flag, no LLM
  if (docFiles.length > 0) {
    const flagPath = join(GRAPH_DIR, 'needs_update');
    const logPath = join(GRAPH_DIR, 'needs_update.log');
    try {
      const ts = new Date().toISOString();
      const entry = `${ts}  ${docFiles.length} doc files changed:\n${docFiles.map((f) => `  ${f}`).join('\n')}\n\n`;
      writeFileSync(flagPath, `Run /graphify --update to refresh semantic graph (${docFiles.length} doc files changed).\nLast: ${ts}\n`);
      let existingLog = '';
      if (existsSync(logPath)) existingLog = readFileSync(logPath, 'utf-8');
      writeFileSync(logPath, entry + existingLog);
      logInfo(`${docFiles.length} doc/md changed → wrote needs_update flag (manual /graphify --update needed)`);
    } catch (e) {
      logInfo(`needs_update flag write failed: ${e.message?.slice(0, 80)} (non-blocking)`);
    }
  }

  // 6. Code files → AST extract on explicit list + merge into graph
  if (codeFiles.length === 0) silentExit('no code files (only docs)');

  const liveCodeFiles = codeFiles.filter((f) => existsSync(join(REPO_ROOT, f)));
  if (liveCodeFiles.length === 0) silentExit('all code files deleted (no AST to extract)');

  // 7. Locate graphify Python interpreter
  const pyPathFile = join(GRAPH_DIR, '.graphify_python');
  let pyPath;
  if (existsSync(pyPathFile)) {
    pyPath = readFileSync(pyPathFile, 'utf-8').replace(/^/, '').trim();
  }
  if (!pyPath || !existsSync(pyPath)) {
    try {
      pyPath = execFileSync('uv', ['tool', 'run', '--from', 'graphifyy', 'python', '-c', 'import sys; print(sys.executable)'], {
        encoding: 'utf-8',
        stdio: ['ignore', 'pipe', 'pipe'],
      }).trim();
    } catch (e) {
      logInfo(`graphify python not resolvable: ${e.message?.slice(0, 80)} — manual /graphify --update needed`);
      process.exit(0);
    }
  }

  // 8. Run AST extract + merge via Python one-liner
  const liveListJson = JSON.stringify(liveCodeFiles);
  const pyCode = `
import sys, json
from pathlib import Path
from graphify.extract import extract
from graphify.build import build_merge
from graphify.export import to_json

repo_root = Path(${JSON.stringify(REPO_ROOT)})
files = [repo_root / f for f in json.loads('''${liveListJson}''')]
ast = extract(files, cache_root=repo_root)
ast_nodes = len(ast.get('nodes', []))
ast_edges = len(ast.get('edges', []))
print(f'[graphify-safe-update] AST: {ast_nodes} nodes, {ast_edges} edges from {len(files)} code files')

# dedup=False для incremental: дефолтный dedup=True агрессивно фьюз-дедупит весь
# merged граф (483 exact + 447 fuzzy на 6305-node графе → 5356), to_json потом
# refuses overwrite смаленьшим графом. dedup=False → чистый union по ID.
graph_path = repo_root / 'graphify-out' / 'graph.json'
G = build_merge([ast], graph_path=str(graph_path), dedup=False)
to_json(G, dict(), str(graph_path))
print(f'[graphify-safe-update] merged: {G.number_of_nodes()} nodes, {G.number_of_edges()} edges in graph.json')
`;

  try {
    const out = execFileSync(pyPath, ['-c', pyCode], {
      encoding: 'utf-8',
      stdio: ['ignore', 'pipe', 'pipe'],
      cwd: REPO_ROOT,
    });
    process.stdout.write(out);
  } catch (e) {
    logInfo(`AST extract/merge failed (non-blocking): ${e.message?.slice(0, 200)}`);
    if (e.stderr) process.stderr.write(e.stderr.toString());
  }

  process.exit(0);
}