// Node-page Discord picker (server-26#213 item 3, #109 item 13).
// Shapes returned by c2-core app/routers/discord_web.py. No token strings —
// the server never sends them to the browser.

export type StreamState =
  | "pending"
  | "connecting"
  | "connected"
  | "error"
  | "stopping"
  | "stopped"
  | "node_offline"
  | "paused_locally";

export interface DiscordStreamView {
  stream_id: string;
  guild_id: string;
  channel_id: string;
  guild_name: string | null;
  channel_name: string | null;
  system_id?: string | null;
  system_name: string | null;
  /** The radio bot carrying it — tells apart several streams in one voice channel. */
  token_name?: string | null;
  mode: "persistent" | "adhoc" | null;
  node_id: string | null;
  node_name: string | null;
  actual: { state: StreamState; error: string | null; code?: string | null; since?: string; at?: string } | null;
  updated_at: string | null;
}

export interface DiscordInvite {
  name: string;
  invite_url: string;
}

export interface DiscordVoiceChannel {
  channel_id: string;
  name: string;
  category: string | null;
  /** This node's system's stream in the channel, if any — what a pick restarts or moves. */
  stream: DiscordStreamView | null;
  /** Every live stream in the channel (several systems can share it, each its own bot). */
  streams?: DiscordStreamView[];
}

export interface DiscordGuildOption {
  guild_id: string;
  name: string | null;
  linked: boolean;
  synced: boolean;
  synced_at: string | null;
  voice_channels: DiscordVoiceChannel[];
  streams_on: number;
  bot: { ok: boolean; code: string | null; message: string | null; invite: DiscordInvite[] };
}

export interface DiscordJoinOptions {
  node_id: string;
  node_name: string | null;
  node_online: boolean;
  system_id: string | null;
  system_name: string | null;
  can_control: boolean;
  /** Permanent removal: platform admin or the org owner only (operators can stop, not remove). */
  can_remove?: boolean;
  limits: { node_max: number; node_used: number; guild_max: number };
  guilds: DiscordGuildOption[];
  streams: DiscordStreamView[];
}

/** GET /tokens/org/preferred — the org's own systems and its own (bring-your-own) radio bots. */
export interface OrgPreferredBots {
  org_id: string;
  systems: {
    system_id: string;
    name: string;
    preferred_token_id: string | null;
    /** A platform admin pinned a DRB pool bot for this system. */
    preferred_is_platform_bot: boolean;
    preferred_name: string | null;
  }[];
  bots: {
    token_id: string;
    name: string;
    valid: boolean | null;
    server_count: number | null;
    preferred_for_system_id: string | null;
    invite_url: string | null;
  }[];
}

export interface DiscordStartResult {
  ok: boolean;
  stream_id: string;
  token_id: string | null;
  delivered: boolean | null;
  reused: boolean | null;
}

export interface ParsedC2Error {
  message: string;
  invite: DiscordInvite[];
  /** start_stream's code: missing_permissions, preferred_busy, preferred_other_node, bad_channel, … */
  code: string | null;
  status: number | null;
}

function asStrings(v: unknown): string[] {
  return Array.isArray(v) ? v.filter((x): x is string => typeof x === "string") : [];
}

/** A bot's trace sentence: ``reason`` as a string, else the ``reasons`` map
 *  (label → sentence, discord_perms.check_voice) joined. */
function reasonOf(b: Record<string, unknown>): string | null {
  if (typeof b.reason === "string" && b.reason) return b.reason;
  const r = b.reasons;
  if (r && typeof r === "object") {
    const parts = Object.entries(r as Record<string, unknown>)
      .filter(([, v]) => typeof v === "string" && v)
      .map(([k, v]) => `${k}: ${v as string}`);
    if (parts.length) return parts.join("; ");
  }
  return null;
}

/** c2api's request() throws `C2 API error <status>: <body>`. Pull the
 *  detail, code and invite links back out of a JSON body. */
export function parseC2Error(err: unknown): ParsedC2Error {
  const raw = err instanceof Error ? err.message : String(err);
  const m = raw.match(/^C2 API error (\d+): ([\s\S]*)$/);
  const status = m ? Number(m[1]) : null;
  const idx = raw.indexOf(": ");
  if (idx >= 0) {
    try {
      const body = JSON.parse(raw.slice(idx + 2));
      const detail = typeof body?.detail === "string" ? body.detail : null;
      const invite = Array.isArray(body?.invite)
        ? (body.invite as DiscordInvite[]).filter((i) => i && typeof i.invite_url === "string")
        : [];
      // missing_permissions: detail already names each bot, the permission,
      // what removed it and the fix (discord_streams._missing_permissions_error).
      if (detail) return { message: detail, invite, code: typeof body?.code === "string" ? body.code : null, status };
    } catch {
      /* not JSON — fall through */
    }
  }
  return { message: raw, invite: [], code: null, status };
}

// ---------------------------------------------------------------------------
// Voice-channel permission check (server-26#225 S3/S4) — the JSON contract of
// c2-core routers/discord_checks.py:
//   GET /discord/nodes/{node}/guilds/{guild}/voice-check  (node picker, org-scoped)
//   GET /discord/guilds/{guild}/voice-check?channel_id=   (admin Add form; rows carry token_id)
// Bot names only for non-admins — never token strings.
// ---------------------------------------------------------------------------

/** Per bot: ok | denied | unknown | not_member | invalid | bad_channel | unchecked. */
export type BotAccess = "ok" | "denied" | "unknown" | "not_member" | "invalid" | "bad_channel" | "unchecked";

/** Per channel, as c2-core sums it up over the bots that are free. */
export type ChannelState = "ready" | "needs_fix" | "unknown" | "busy" | "no_bot" | "bad_channel" | "unchecked";

export interface VoiceCheckBot {
  /** Admin route only. */
  token_id?: string | null;
  name: string;
  status: BotAccess;
  /** true = can stream there, false = DEFINITE deny, null = anything else (unknown fails open). */
  ok: boolean | null;
  missing: string[];
  /** What removed the first missing permission, e.g. "denied by #dispatch's override for @Muted". */
  reason: string | null;
  /** What to change in Discord (server-written). */
  fix: string | null;
  /** false = this bot can't take a new stream here right now. */
  available: boolean | null;
  unavailable_reason: "busy_here" | "other_node" | string | null;
}

export interface VoiceCheckChannel {
  channel_id: string;
  name: string | null;
  state: ChannelState | null;
  /** Advisory: REST can't see who is connected (0 = no limit). */
  user_limit: number;
  any_ok: boolean | null;
  bots: VoiceCheckBot[];
}

export interface VoiceCheck {
  guild_id: string | null;
  checked_at: string | null;
  /** false when DISCORD_PERM_CHECK_ENABLED is off server-side — no badges then. */
  enabled: boolean;
  /** false when a Re-check was asked for but rate limited (cached answer served). */
  refreshed: boolean | null;
  channels: Record<string, VoiceCheckChannel>;
  /** Radio bots that could be invited to this server. */
  invite: DiscordInvite[];
}

const BOT_ACCESS: readonly string[] = ["ok", "denied", "unknown", "not_member", "invalid", "bad_channel", "unchecked"];
const CHANNEL_STATES: readonly string[] = ["ready", "needs_fix", "unknown", "busy", "no_bot", "bad_channel", "unchecked"];

function normBot(b: Record<string, unknown>): VoiceCheckBot {
  const status = (typeof b.status === "string" && BOT_ACCESS.includes(b.status)
    ? b.status
    : b.ok === true ? "ok" : "unknown") as BotAccess;
  return {
    token_id: typeof b.token_id === "string" ? b.token_id : null,
    name: typeof b.name === "string" && b.name ? b.name : "Radio bot",
    status,
    ok: status === "ok" ? true : status === "denied" ? false : null,
    missing: asStrings(b.missing),
    reason: reasonOf(b),
    fix: typeof b.fix === "string" && b.fix ? b.fix : null,
    available: b.available === true ? true : b.available === false ? false : null,
    unavailable_reason: typeof b.unavailable_reason === "string" ? b.unavailable_reason : null,
  };
}

function normChannel(c: Record<string, unknown>, fallbackId: string): VoiceCheckChannel {
  return {
    channel_id: String(c.channel_id ?? fallbackId),
    name: typeof c.name === "string" ? c.name : null,
    state: typeof c.state === "string" && CHANNEL_STATES.includes(c.state) ? (c.state as ChannelState) : null,
    user_limit: Number(c.user_limit) || 0,
    any_ok: c.any_ok === true ? true : c.any_ok === false ? false : null,
    bots: Array.isArray(c.bots) ? (c.bots as Record<string, unknown>[]).filter(Boolean).map(normBot) : [],
  };
}

export function normalizeVoiceCheck(raw: unknown): VoiceCheck {
  const r = (raw && typeof raw === "object" ? raw : {}) as Record<string, unknown>;
  const channels: Record<string, VoiceCheckChannel> = {};
  if (Array.isArray(r.channels)) {
    for (const c of r.channels as Record<string, unknown>[]) {
      if (c && c.channel_id != null) channels[String(c.channel_id)] = normChannel(c, String(c.channel_id));
    }
  }
  return {
    guild_id: r.guild_id != null ? String(r.guild_id) : null,
    checked_at: typeof r.checked_at === "string" ? r.checked_at : null,
    enabled: r.enabled !== false,
    refreshed: r.refreshed === true ? true : r.refreshed === false ? false : null,
    channels,
    invite: Array.isArray(r.invite)
      ? (r.invite as DiscordInvite[]).filter((i) => i && typeof i.invite_url === "string")
      : [],
  };
}

export type ChannelVerdict =
  /** A free radio bot can stream there. */
  | { kind: "ready"; limit: number }
  /** A bot could stream there, but every such bot is busy. */
  | { kind: "busy"; limit: number }
  /** Every free bot is DEFINITELY denied — Start is disabled. */
  | { kind: "fix"; limit: number; bot: VoiceCheckBot }
  /** Discord didn't answer for some bot — Start stays enabled (fail-open). */
  | { kind: "unknown"; limit: number }
  /** No radio bot is in this server. */
  | { kind: "no_bot"; limit: number }
  /** The channel exists but is not a voice channel — Start is disabled. */
  | { kind: "not_voice"; limit: number };

/** Derive the badge. c2-core's ``state`` wins; the bot rows are the fallback.
 *  null = no badge (check off, or no data for that channel). */
export function channelVerdict(c: VoiceCheckChannel | null | undefined): ChannelVerdict | null {
  if (!c) return null;
  const limit = c.user_limit;
  const free = c.bots.filter((b) => b.available !== false);
  const denied = free.filter((b) => b.ok === false);
  const firstDenied = denied[0] ?? c.bots.find((b) => b.ok === false);
  switch (c.state) {
    case "ready": return { kind: "ready", limit };
    case "busy": return { kind: "busy", limit };
    case "unknown": return { kind: "unknown", limit };
    case "no_bot": return { kind: "no_bot", limit };
    case "bad_channel": return { kind: "not_voice", limit };
    case "unchecked": return null;
    case "needs_fix": return firstDenied ? { kind: "fix", limit, bot: firstDenied } : { kind: "unknown", limit };
  }
  // No state (older server): same rules as discord_checks._channel_state.
  if (!c.bots.length) return { kind: "no_bot", limit };
  if (free.some((b) => b.ok === true)) return { kind: "ready", limit };
  if (free.some((b) => b.ok === null)) return { kind: "unknown", limit };
  if (denied.length) return { kind: "fix", limit, bot: denied[0] };
  if (c.bots.some((b) => b.ok === true)) return { kind: "busy", limit };
  return { kind: "unknown", limit };
}

/** A definite refusal: Start would only get a 409. Everything else fails open. */
export function blocksStart(v: ChannelVerdict | null | undefined): boolean {
  return v?.kind === "fix" || v?.kind === "not_voice";
}

/** "#dispatch" for a channel name, else "this channel". */
export function channelRef(name: string | null | undefined): string {
  return name ? `#${name.replace(/^#/, "")}` : "this channel";
}

function joinLabels(labels: string[]): string {
  if (labels.length <= 1) return labels.join("");
  return `${labels.slice(0, -1).join(", ")} or ${labels[labels.length - 1]}`;
}

/** "Radio bot X can't Speak in #dispatch: denied by #dispatch's override for @Muted." */
export function deniedSentence(bot: { name: string; missing: string[]; reason: string | null }, channelName?: string | null): string {
  const what = bot.missing.length ? joinLabels(bot.missing) : "join";
  const why = bot.reason ? `: ${bot.reason}` : "";
  return `${bot.name} can't ${what} in ${channelRef(channelName)}${why}.`;
}

/** Where in Discord to fix it — c2-core's own sentence when it sent one. */
export function fixSentence(bot: { name: string; missing: string[]; reason: string | null; fix?: string | null }): string {
  if (bot.fix) return bot.fix;
  if (bot.reason && /timed out/i.test(bot.reason)) return `In Discord: remove ${bot.name}'s timeout, then Re-check.`;
  const perms = bot.missing.length ? bot.missing.join(" and ") : "View Channel, Connect and Speak";
  return `In Discord: Edit Channel → Permissions → add ${bot.name} → allow ${perms}, then Re-check.`;
}

/** "40s ago" / "3 min ago" for the Re-check footer. */
export function agoText(iso: string | null | undefined, now = Date.now()): string | null {
  if (!iso) return null;
  const t = Date.parse(iso);
  if (Number.isNaN(t)) return null;
  const s = Math.max(0, Math.round((now - t) / 1000));
  if (s < 60) return `${s}s ago`;
  const m = Math.round(s / 60);
  return m < 60 ? `${m} min ago` : `${Math.round(m / 60)} h ago`;
}

/** One line per bot for the expandable details. */
export function botLine(b: VoiceCheckBot, channelName?: string | null): { tone: "ok" | "bad" | "warn" | "muted"; text: string } {
  const busy =
    b.unavailable_reason === "busy_here"
      ? "already in another voice channel in this server (one per server)"
      : b.unavailable_reason === "other_node"
        ? "carrying radio on another node"
        : "busy";
  switch (b.status) {
    case "ok":
      return b.available === false
        ? { tone: "warn", text: `${b.name}: can stream here, but is ${busy}` }
        : { tone: "ok", text: `${b.name}: ready` };
    case "denied":
      return { tone: "bad", text: deniedSentence(b, channelName) + (b.available === false ? ` (also ${busy})` : "") };
    case "not_member":
      return { tone: "warn", text: `${b.name}: Discord says it is not in this server — invite it again` };
    case "invalid":
      return { tone: "bad", text: `${b.name}: its token was rejected by Discord — a platform admin has to replace it` };
    case "bad_channel":
      return { tone: "bad", text: `${b.name}: ${channelRef(channelName)} is not a voice channel` };
    case "unchecked":
      return { tone: "muted", text: `${b.name}: not checked (permission check is off)` };
    default:
      return { tone: "muted", text: `${b.name}: couldn't check${b.reason ? ` (${b.reason})` : ""} — DRB will still try it` };
  }
}