/**
 * Shared host CLI flags for seeder/booter standalones and package entrypoints.
 */
import path from 'path'

/**
 * @param {string[]} argv
 * @returns {{ datadir: string|null, rest: string[] }}
 */
export function parseHostFlags(argv) {
  let datadir = null
  const rest = []
  for (let i = 0; i < argv.length; i++) {
    const a = argv[i]
    if (a === '--datadir' || a === '--data-dir') {
      const v = argv[++i]
      if (v != null && v !== '') datadir = v
    } else if (a.startsWith('--datadir=')) {
      datadir = a.slice('--datadir='.length)
    } else if (a.startsWith('--data-dir=')) {
      datadir = a.slice('--data-dir='.length)
    } else {
      rest.push(a)
    }
  }
  const trimmed = datadir != null ? String(datadir).trim() : ''
  return { datadir: trimmed || null, rest }
}

/**
 * Apply `--datadir` to `BARE_OS_HOST_DATA` before Corestore paths are resolved.
 * @param {string|null|undefined} datadir
 * @returns {string|null}
 */
export function applyHostDataDir(datadir) {
  if (!datadir) return null
  const resolved = path.resolve(String(datadir))
  if (typeof globalThis.process === 'undefined') {
    globalThis.process = { env: {} }
  }
  if (!globalThis.process.env) globalThis.process.env = {}
  globalThis.process.env.BARE_OS_HOST_DATA = resolved
  return resolved
}

/**
 * Parse argv and set BARE_OS_HOST_DATA when `--datadir` is present.
 * @param {string[]} argv
 * @returns {{ datadir: string|null, rest: string[] }}
 */
export function applyHostFlagsFromArgv(argv) {
  const parsed = parseHostFlags(argv)
  if (parsed.datadir) applyHostDataDir(parsed.datadir)
  return parsed
}