/**
 * Internal platform-profile builders for the local sandbox provider.
 *
 * @module @deepseek-ai/dsh-sandbox-local/profiles
 */

import { realpathSync } from 'node:fs'
import { tmpdir } from 'node:os'
import { grantArgs as landlockGrantArgs } from 'node-addon-landlock-run'
import type { SandboxPolicy } from '@deepseek-ai/dsh-sandbox'

/**
 * Build the bwrap profile arguments for one file-effect policy.
 * @param policy - file-effect policy to express as bwrap mounts.
 * @returns profile arguments before the trailing separator and command argv.
 */
export function bwrapProfileArgs(policy: SandboxPolicy): string[] {
  const args = ['--ro-bind', '/', '/', '--dev', '/dev', '--proc', '/proc', '--die-with-parent']
  if (policy.mode === 'workspace-write') {
    args.push('--tmpfs', '/tmp')
    args.push('--bind', policy.workspaceRoot, policy.workspaceRoot)
  }
  return args
}

/**
 * Build the Landlock launcher grants for one file-effect policy.
 * @param policy - file-effect policy to express as Landlock allow-list grants.
 * @returns launcher grant arguments before the trailing separator and command argv.
 */
export function landlockProfileArgs(policy: SandboxPolicy): string[] {
  const readWrite = ['/dev/null']
  if (policy.mode === 'workspace-write') {
    readWrite.push('/tmp', policy.workspaceRoot)
  }
  return landlockGrantArgs({ readOnly: ['/'], readWrite })
}

/** Resolve a granted root to the canonical path the Seatbelt kernel sees. */
function canonicalPath(path: string): string {
  try {
    return realpathSync(path)
  } catch {
    // Missing or unreadable roots stay as spelled; an unresolved root grants
    // nothing until it exists, which is the conservative outcome.
    return path
  }
}

/** Quote one path as an SBPL string literal. */
function sbplString(path: string): string {
  return `"${path.replaceAll('\\', String.raw`\\`).replaceAll('"', String.raw`\"`)}"`
}

/**
 * Build the sandbox-exec arguments and SBPL profile for one policy.
 * @param policy - file-effect policy to express as an SBPL profile.
 * @returns sandbox-exec arguments before the trailing separator and command argv.
 */
export function seatbeltProfileArgs(policy: SandboxPolicy): string[] {
  const forms = ['(version 1)', '(allow default)', '(deny file-write*)', `(allow file-write* (literal ${sbplString('/dev/null')}))`]
  if (policy.mode === 'workspace-write') {
    const roots = [...new Set([policy.workspaceRoot, '/tmp', tmpdir()].map(canonicalPath))]
    forms.push(`(allow file-write* ${roots.map(root => `(subpath ${sbplString(root)})`).join(' ')})`)
  }
  return ['-p', forms.join(' ')]
}