// ── The public demo's module-side locks (DEMO_MODE.md §3.4, §3.5) ──────────
//
// Core locks this module's two rig-link routes and the player's Steam unlink by
// `demoLocks` in module.json. What a route list cannot express lives here, behind
// `ctx.demoMode` (MODULE_API 1.18.0), and every handler that enforces one of these
// asks this file:
//
//   the staff Steam unlink on Admin → Users (step-5 walk, W4): it serves under
//     core's users mount, which a module's demoLocks may not name, so its handler
//     refuses instead. The demo player's seeded link stays put either way;
//   the console-command deny list (§3.4, DM11): the commands that would break
//     the rig for every visitor until the next wipe. Asked at save, through
//     core's `demoRefuses` hook (1.19.0, DM18), and again at run;
//   the bridge's own config (§3.5, DM14): neither readable nor writable, because
//     it holds the bridge's link to the sidecar and its credentials;
//   secrets in every other config: redacted on the way out, read-only on the
//     way in, and no raw-JSON saves.
//
// Off the demo nothing here refuses anything. The server is the lock (DM10):
// the UI may explain a refusal, but no screen is relied on to make one.

const core = require('./core')

const CODE = 'DEMO_LOCKED'
const MESSAGE = 'This is turned off on the demo site.'

/** Whether this is the public demo. */
function isDemo() {
  return core.demoMode
}

/** The demo's refusal, in core's shape, so core's one toast shows it. */
function refuse(res, message = MESSAGE, extra = {}) {
  return res.status(403).json({ message, code: CODE, ...extra })
}

// ── The console-command deny list (§3.4, DM11) ─────────────────────────────

/** Denied by first word, exactly. */
const DENIED = new Set(['quit', 'restart', 'oxide.unload', 'oxide.reload', 'fps.limit', 'server.tickrate'])

/** Denied by prefix: every RCON command. */
const DENIED_PREFIXES = ['rcon.']

/**
 * The command a line runs, as the deny list compares it: the first word,
 * lower-cased, with a leading `global.` stripped (Rust accepts `global.quit`)
 * and the `o.` short form spelled `oxide.` (`o.unload`). Only the first word,
 * so arguments cannot hide a denied command; `;` does not split a Rust console
 * line (the §16 spike), so there is no second command to look for.
 */
function commandWord(line) {
  let word = String(line === undefined || line === null ? '' : line).trim().split(/\s+/)[0].toLowerCase()
  if (word.startsWith('global.')) word = word.slice('global.'.length)
  if (word.startsWith('o.')) word = `oxide.${word.slice('o.'.length)}`
  return word
}

/** Whether one console line is denied on the demo, by its first word. */
function isDeniedCommand(line) {
  const word = commandWord(line)
  if (!word) return false
  return DENIED.has(word) || DENIED_PREFIXES.some((prefix) => word.startsWith(prefix))
}

/**
 * The refusal sentence for a list of console lines, or null when none is
 * denied — or when this is not the demo. Names the line as the author typed it.
 */
function deniedCommand(lines) {
  if (!isDemo()) return null
  const items = Array.isArray(lines) ? lines : lines === undefined || lines === null ? [] : [lines]
  const hit = items.find((line) => isDeniedCommand(line))
  return hit === undefined ? null : `"${String(hit).trim()}" is turned off on the demo site.`
}

// ── The bridge's own config (§3.5, DM14) ───────────────────────────────────

/**
 * The bridge plugin's name. The catalogue's `self` is the plugin's own word for
 * it and is used when it is there; this is the floor, so a catalogue that could
 * not be read never unlocks the file (the lock fails closed).
 */
const BRIDGE = 'RunicGateway'

/**
 * A config path in the form the host will resolve it to, for the bridge test
 * only: `.` segments dropped, each segment trimmed of the spaces and trailing
 * dots Windows ignores, and lower-cased. `./RunicGateway.json` and
 * `RunicGateway /x.json` are the bridge's files on some host, so they are the
 * bridge's files here.
 */
function canonicalSegments(path) {
  return String(path || '')
    .split(/[\\/]+/)
    // A `.` segment trims to nothing and is dropped with the empty ones.
    .map((segment) => segment.trim().replace(/[. ]+$/, ''))
    .filter(Boolean)
    .map((segment) => segment.toLowerCase())
}

/**
 * Whether a config path belongs to the bridge plugin: its first segment, or its
 * file name at the root, is the bridge's name. `self` is the catalogue's.
 */
function isBridgePath(path, self) {
  const names = new Set([BRIDGE.toLowerCase()])
  if (self) names.add(String(self).toLowerCase())
  const parts = canonicalSegments(path)
  if (!parts.length) return false
  const first = parts.length > 1 ? parts[0] : parts[0].replace(/\.json$/, '')
  return names.has(first)
}

/** Whether a plugin name (a catalogue group, an audit row's plugin) is the bridge. */
function isBridgePlugin(plugin, self) {
  const name = String(plugin || '').toLowerCase()
  return name === BRIDGE.toLowerCase() || (self ? name === String(self).toLowerCase() : false)
}

// ── Secrets in every other config (§3.5) ───────────────────────────────────

/** What a redacted value reads as, in the text and in the form. */
const REDACTED = '(hidden on the demo site)'

module.exports = {
  CODE,
  MESSAGE,
  BRIDGE,
  REDACTED,
  isDemo,
  refuse,
  commandWord,
  isDeniedCommand,
  deniedCommand,
  canonicalSegments,
  isBridgePath,
  isBridgePlugin,
}