#!/usr/bin/env bun
// Writes cli/data/flags.json: the --flags every command accepts, so the dispatcher (cli/index.ts) can reject an
// unknown flag (a typo like --dyr) with the usage before anything runs, also in the compiled sidecar (no sources).
// For each command in cli/commands.ts it follows the command module and every local module it imports (static and
// dynamic), and collects the literal flag reads: <x>.has('name'), .get, .str, .num, .list, .many, .required. Reads with a computed
// name are listed in DYNAMIC below (the scan fails on a new one until it is added there). `ws` forwards its flags to the
// command it runs, so it accepts every flag. GLOBAL flags work on every command. The usage lines of each module's
// header comment (`//   storebound <command> ...`) go along, for `storebound <command> --help`.
//   bun tools/gen-flags.ts            write cli/data/flags.json
//   bun tools/gen-flags.ts --check    exit 1 when the file is stale (tests/cli-help.test.ts runs it)
import { existsSync, readFileSync, writeFileSync } from 'node:fs';
import { dirname, join, relative, resolve } from 'node:path';

const ROOT = resolve(import.meta.dir, '..');
const CLI = join(ROOT, 'cli');
const OUT = join(CLI, 'data', 'flags.json');

/** Flags every command accepts (read by the dispatcher, lib/ctx, lib/lock, or harmless where unused). */
export const GLOBAL = ['account', 'config', 'dry', 'force-unlock', 'help', 'json', 'only', 'verbose', 'yes'];
/** Computed flag reads, per file (relative to cli/): the flags they can read. */
const DYNAMIC: Record<string, string[]> = {
  'prices.ts': ['out', 'csv'],
  'play/rollout.ts': ['halt', 'resume', 'complete'],
  'play/release.ts': ['internal', 'alpha', 'beta', 'production'],
  'ads/apple.ts': ['adgroup', 'campaign', 'keyword'],
  'lib/price-gate.ts': [], // withoutYes: a wrapper of ctx.args.has(n) (confirm without --yes)
  'lib/declarations.ts': [], // a.get(k) on a Map, not the args
  'lib/catalog.ts': [], // a.get(w.id) on a Map, not the args
};
/** Commands that pass their flags on to another command. */
const FORWARDS = new Set(['ws']);

// the receiver is captured so HTTP headers and URL search params (res.headers.get('content-type')) are not flags
const READ = /([\w$.)\]]*)\.(?:has|get|str|num|list|many|required)\(\s*(['"])([a-z][a-z0-9-]*)\2/g;
const NOT_ARGS = /(?:headers|searchParams|params|url|env)$/i;
const COMPUTED = /\b(?:args|a|ctx\.args)\.(?:has|get|str|num|list|many|required)\(\s*(?![\s'"])/g;
const IMPORT = /(?:\bfrom\s+|\bimport\s*\(\s*)'(\.{1,2}\/[^']+)'/g;

function file(spec: string, from: string): string | null {
  const base = resolve(dirname(from), spec);
  for (const f of [base, base + '.ts', join(base, 'index.ts')]) if (f.endsWith('.ts') && existsSync(f)) return f;
  return null;
}

function scan(entry: string, errors: string[]): Set<string> {
  const flags = new Set<string>(), seen = new Set<string>(), todo = [entry];
  while (todo.length) {
    const f = todo.pop()!;
    if (seen.has(f)) continue;
    seen.add(f);
    const rel = relative(CLI, f);
    // lib/embedded.ts holds file texts (templates, shots pages: their own scripts read URL params), not flag reads
    if (rel === 'index.ts' || rel === 'commands.ts' || rel === join('lib', 'embedded.ts')) continue;
    const src = readFileSync(f, 'utf8');
    for (const m of src.matchAll(READ)) if (!NOT_ARGS.test(m[1]!)) flags.add(m[3]!);
    for (const fl of DYNAMIC[rel] ?? []) flags.add(fl);
    if (!(rel in DYNAMIC)) for (const m of src.matchAll(COMPUTED)) {
      const line = src.slice(0, m.index).split('\n').length;
      errors.push(`cli/${rel}:${line}: flag read with a computed name; list the flags it can read in DYNAMIC (tools/gen-flags.ts)`);
    }
    for (const m of src.matchAll(IMPORT)) { const g = file(m[1]!, f); if (g && g.startsWith(CLI)) todo.push(g); }
  }
  return flags;
}

/** The usage lines of a module's header comment: `//   storebound <key> ...`. */
function usageLines(f: string, key: string): string[] {
  const out: string[] = [];
  for (const line of readFileSync(f, 'utf8').split('\n')) {
    if (!line.startsWith('//')) break;
    const m = /^\/\/\s+(storebound .*)$/.exec(line);
    if (m && (m[1]! + ' ').startsWith(`storebound ${key} `)) out.push(m[1]!.trimEnd());
  }
  return out;
}

export function build(): { table: Record<string, string[]>; usage: Record<string, string[]>; errors: string[] } {
  const src = readFileSync(join(CLI, 'commands.ts'), 'utf8');
  const errors: string[] = [];
  const per: Record<string, string[]> = {}, usage: Record<string, string[]> = {};
  for (const m of src.matchAll(/^ {2}'([a-z][a-z0-9 -]*)': \[.*?import\('(\.\/[^']+)'\)/gm)) {
    const f = file(m[2]!, join(CLI, 'commands.ts'));
    if (!f) { errors.push(`${m[1]}: module ${m[2]} not found`); continue; }
    per[m[1]!] = [...scan(f, errors)].filter(x => !GLOBAL.includes(x)).sort();
    const u = usageLines(f, m[1]!);
    if (u.length) usage[m[1]!] = u;
  }
  const all = [...new Set(Object.values(per).flat())].sort();
  for (const k of FORWARDS) if (per[k]) per[k] = all;
  const table = Object.fromEntries(Object.keys(per).sort().map(k => [k, per[k]!]));
  return { table, usage: Object.fromEntries(Object.keys(usage).sort().map(k => [k, usage[k]!])), errors: [...new Set(errors)] };
}

if (import.meta.main) {
  const { table, usage, errors } = build();
  if (errors.length) { console.error(errors.join('\n')); process.exit(1); }
  const text = JSON.stringify({ global: GLOBAL, commands: table, usage }, null, 1) + '\n';
  if (process.argv.includes('--check')) {
    const cur = existsSync(OUT) ? readFileSync(OUT, 'utf8') : '';
    if (cur !== text) { console.error('cli/data/flags.json is stale: run bun tools/gen-flags.ts'); process.exit(1); }
    console.log(`flags: ${Object.keys(table).length} commands, fresh`);
  } else {
    writeFileSync(OUT, text);
    console.log(`flags: ${Object.keys(table).length} commands -> ${relative(ROOT, OUT)}`);
  }
}