/**
 * @fileoverview `codeman agent …` — session-to-session verbs for the agent running
 * inside a Codeman session, in every CLI mode.
 *
 * A thin HTTP client over endpoints that already exist (`quick-start`, `input`,
 * `wait`, `wait-output`, `last-response`, `terminal`, `DELETE sessions/:id`). It
 * invents no route and no transport: everything goes through `CODEMAN_API_URL`, so
 * auth, ownership and the per-session waiter cap apply unchanged. The behaviour is
 * the packaged agent skill's (`skills/codeman`), ported from shell prose into code
 * with tests, so a `codex`/`opencode`/`pi` agent — which never gets the claude-only
 * preamble — has the same verbs from one line in its AGENTS.md.
 *
 * Invariants (each asserted in `test/cli-agent.test.ts`):
 * 1. Refuses outside a Codeman session (`CODEMAN_MUX=1` + `CODEMAN_API_URL`); it
 *    never guesses a URL — a server you are not part of is not yours to drive.
 * 2. `send` transmits printable text plus `\r` only. ESC exists solely as
 *    `interrupt`, which never appends `\r`. A stray control byte is a dead session
 *    in the fullscreen TUIs (opencode's `Ctrl+C` is `app_exit`).
 * 3. `rm` fails closed: empty id, a short self id, or a prefix match in EITHER
 *    direction refuses. Ids appear in full and 8-char form, so equality alone
 *    misses a real combination — and the miss deletes the caller.
 * 4. An id shorter than 8 characters refuses (exit 4) before any request, on every
 *    verb. `9` would resolve to whichever session is alone with that first
 *    character, the user's own interactive tab included.
 *
 * Commands live here as functions returning an exit code, not calling
 * `process.exit`, so the whole surface is unit-testable against a fake server.
 *
 * @module cli-agent
 */
import http from 'node:http';
import https from 'node:https';
import type { Command } from 'commander';
import {
  basicAuthHeader,
  credentialsFrom,
  readCodemanEnvFile,
  type CodemanCredentials,
} from './codeman-credentials.js';
import { getCli } from './config/cli-registry/registry.js';
import { GLYPH, palette, table } from './cli-style.js';
import { getErrorMessage } from './types.js';
import { stripAnsi as stripAnsiSequences } from './utils/regex-patterns.js';

// ─────────────────────────────────────────────────────────────────────────────
// Context and guard
// ─────────────────────────────────────────────────────────────────────────────

export interface AgentContext {
  /** Base URL of the Codeman server, from `CODEMAN_API_URL`. */
  apiUrl: string;
  /** This session's id, from `CODEMAN_SESSION_ID`. */
  selfId: string;
  /** Basic-auth credentials, when the server has a password. */
  auth?: CodemanCredentials;
}

/** Thrown when the process is not inside a Codeman-managed session. */
export class AgentGuardError extends Error {}

/** Exit codes shared by every verb; a shell agent can branch on them. */
export const EXIT = {
  ok: 0,
  error: 1,
  timeout: 2,
  dead: 3,
  refused: 4,
} as const;

/**
 * Resolve the context from the environment, or throw `AgentGuardError`.
 *
 * Credentials in the order every client of the API uses (`credentialsFrom`, shared
 * with `codeman attach` and the TUI): each field from the environment (a session
 * inherits the server's), then the data dir's `.env`. No password means the server
 * is open (single-user) — or it is not, and the 401 says so.
 */
export function resolveAgentContext(
  env: NodeJS.ProcessEnv = process.env,
  envFile: () => Record<string, string> = readCodemanEnvFile
): AgentContext {
  if (env.CODEMAN_MUX !== '1') {
    throw new AgentGuardError('Not inside a Codeman-managed session (CODEMAN_MUX is not 1); refusing to act.');
  }
  const apiUrl = env.CODEMAN_API_URL?.trim();
  if (!apiUrl) {
    throw new AgentGuardError('CODEMAN_API_URL is not set; refusing to guess a server.');
  }
  const selfId = env.CODEMAN_SESSION_ID?.trim();
  if (!selfId) {
    throw new AgentGuardError('CODEMAN_SESSION_ID is not set; cannot tell which session is me.');
  }
  const credentials = credentialsFrom(env, envFile());
  return { apiUrl, selfId, auth: credentials.password ? credentials : undefined };
}

// ─────────────────────────────────────────────────────────────────────────────
// Pure helpers (the invariants)
// ─────────────────────────────────────────────────────────────────────────────

/**
 * Is `id` this session? Prefix in BOTH directions, because ids appear in full and
 * in 8-char form (mux names, UI surfaces, Docker's truncated `$SELF`). A self id
 * shorter than 8 characters cannot prove anything and is treated as "maybe me".
 */
export function isSelfSession(selfId: string, id: string): boolean {
  if (!id || selfId.length < 8) return true;
  return id.startsWith(selfId) || selfId.startsWith(id);
}

/** Why `rm` refuses, or `undefined` when the delete may go ahead. */
export function deleteRefusal(selfId: string, id: string): string | undefined {
  if (!id) return 'refusing: empty session id';
  if (selfId.length < 8) return 'refusing: own session id unset or too short to prove this is not me';
  if (isSelfSession(selfId, id)) return `refusing: ${id} is me`;
  return undefined;
}

/**
 * The prompt `send` was given, which must be ONE argument. Joining several with spaces
 * would turn an unquoted `$(cat notes.txt)`, which the shell splits on every newline,
 * back into a single line, so the multi-line refusal below would never see it.
 */
export function sendPromptFromArgs(words: readonly string[]): { text: string } | { error: string } {
  if (words.length === 1) return { text: words[0] };
  return {
    error: `refusing: the prompt must be ONE argument, got ${words.length} — quote it (\`send <id> "…"\`; a prompt that starts with "-" goes after --: \`send <id> -- "- fix the bug"\`)`,
  };
}

/**
 * Why `send` refuses this text, or `undefined` when it is printable. The composer
 * takes one line; the server strips `\r`/`\n` but everything else below 0x20 (and
 * DEL) reaches the pane as a keypress. None of that is a prompt.
 */
export function inputRefusal(text: string): string | undefined {
  if (text.length === 0) return 'refusing: empty input (use `interrupt` for ESC, `send <id> ""` is never a prompt)';
  // The composer is one line: the server strips newlines, which silently joins the
  // lines into one prompt, and a tab reaches the pane as a keypress (claude: mode toggle).
  if (/[\n\r\t]/.test(text)) {
    return 'refusing: input must be a single line (the composer strips newlines and would join your lines) — join them yourself, or write a file into the workspace and send its path';
  }
  // C0, DEL and C1 (U+0080–U+009F: an 8-bit CSI is still a CSI to a terminal).
  // eslint-disable-next-line no-control-regex
  const control = text.match(/[\x00-\x1f\x7f-\x9f]/);
  if (control) {
    const code = control[0].charCodeAt(0).toString(16).padStart(2, '0');
    return `refusing: input contains control byte 0x${code}; send transmits printable text only (ESC is \`interrupt\`)`;
  }
  return undefined;
}

/**
 * Body for `POST /sessions/:id/input` on the send path: text plus `\r` unless the
 * caller asked to type without submitting. Never anything else.
 */
export function buildSendBody(
  text: string,
  options: { enter: boolean; clientId: string; seq: number; wait?: string | true; waitTimeout?: number }
): Record<string, unknown> {
  const body: Record<string, unknown> = {
    input: options.enter ? `${text}\r` : text,
    useMux: true,
    clientId: options.clientId,
    seq: options.seq,
  };
  if (options.wait !== undefined) body.wait = options.wait;
  if (options.waitTimeout !== undefined) body.waitTimeout = options.waitTimeout;
  return body;
}

/** Body for the interrupt path: a bare ESC, and nothing appended — ever. */
export function buildInterruptBody(clientId: string, seq: number): Record<string, unknown> {
  return { input: '\u001b', useMux: true, clientId, seq };
}

/** `clientId` for this caller: fixed per sending session, so `seq` stays monotonic. */
export function defaultClientId(selfId: string, suffix = ''): string {
  return `codeman-agent-cli-${selfId.slice(0, 8)}${suffix ? `-${suffix}` : ''}`;
}

/**
 * Strip a terminal buffer for humans: the shared ANSI strip (CSI, OSC such as window
 * titles, keypad modes) plus the charset designators (`ESC ( B`) it leaves in.
 */
export function stripAnsi(text: string): string {
  // eslint-disable-next-line no-control-regex
  return stripAnsiSequences(text).replace(/\x1b[()][AB0]/g, '');
}

/** Parse a positive-integer option (`--timeout` ms, `--tail` bytes); the server rejects anything else. */
export function parsePositiveInt(raw: string | undefined, fallback: number, flag = '--timeout'): number {
  if (raw === undefined) return fallback;
  const n = Number(raw);
  if (!Number.isInteger(n) || n <= 0) {
    throw new Error(`${flag} must be a positive integer, got "${raw}"`);
  }
  return n;
}

/**
 * Exit code for a wait result: matched or a signal → ok, `exit` or `ended` → dead,
 * timeout → timeout. `ended` is checked BEFORE the happy paths: a worker that dies
 * during `--until stop` comes back as `ended:true, signal:null` (the registry only
 * satisfies waiters that listed `exit`, then cancels the rest), and a `--match` on
 * a dead worker as `ended:true, matched:false` — both are "dead", never "done".
 */
export function waitExitCode(wait: WaitResult | undefined): number {
  if (!wait) return EXIT.error;
  if (wait.signal === 'exit' || wait.ended) return EXIT.dead;
  if (wait.timedOut) return EXIT.timeout;
  if (wait.matched === false) return EXIT.timeout;
  return EXIT.ok;
}

// ─────────────────────────────────────────────────────────────────────────────
// HTTP
// ─────────────────────────────────────────────────────────────────────────────

export interface ApiEnvelope<T = unknown> {
  success: boolean;
  data?: T;
  error?: string;
  errorCode?: string;
}

export interface ApiResponse<T = unknown> {
  status: number;
  /** Parsed envelope, or `undefined` when the body was not JSON (auth guards answer in plain text). */
  json?: ApiEnvelope<T>;
  text: string;
}

export interface WaitResult {
  /** The signal that fired, or null when the wait ended without one. */
  signal?: string | null;
  timedOut?: boolean;
  /** The session went away (deleted / torn down / the write failed) before the wait resolved. */
  ended?: boolean;
  timeoutMs?: number;
  until?: string[];
  matched?: boolean;
  match?: string;
  snippet?: string;
  immediate?: boolean;
}

export interface RequestOptions {
  method: 'GET' | 'POST' | 'DELETE';
  path: string;
  query?: Record<string, string | number | boolean | undefined>;
  body?: Record<string, unknown>;
  headers?: Record<string, string>;
  /** Socket timeout; long-polls pass their own timeout plus headroom. */
  timeoutMs?: number;
  /** Aborts the request (an MCP client cancelling a long wait); the promise rejects. */
  signal?: AbortSignal;
}

export type ApiRequest = (ctx: AgentContext, options: RequestOptions) => Promise<ApiResponse>;

/** Every request carries these; they are ignored on endpoints that do not read them. */
export function baseHeaders(ctx: AgentContext): Record<string, string> {
  const headers: Record<string, string> = { Accept: 'application/json' };
  // Tags sessions this caller spawns as its children (lineage in the web UI).
  // Cosmetic, never fails a call. NOT X-Codeman-Agent-Origin: that one marks a case
  // directory as deletable agent scratch, so it rides only the spawn request that
  // may create one (see agentSpawn), never anything else. Absent for a caller outside
  // any session (`codeman mcp` launched by a desktop MCP client), which has no self.
  if (ctx.selfId) headers['X-Codeman-Parent-Session'] = ctx.selfId;
  const authorization = ctx.auth ? basicAuthHeader(ctx.auth) : undefined;
  if (authorization) headers.Authorization = authorization;
  return headers;
}

/** The real transport. `rejectUnauthorized:false` because the HTTPS install uses a self-signed cert. */
export const httpRequest: ApiRequest = (ctx, options) => {
  const url = new URL(options.path, ctx.apiUrl);
  for (const [key, value] of Object.entries(options.query ?? {})) {
    if (value !== undefined) url.searchParams.set(key, String(value));
  }
  const bodyText = options.body === undefined ? undefined : JSON.stringify(options.body);
  const headers: Record<string, string | number> = { ...baseHeaders(ctx), ...(options.headers ?? {}) };
  if (bodyText !== undefined) {
    headers['Content-Type'] = 'application/json';
    headers['Content-Length'] = Buffer.byteLength(bodyText);
  }
  const transport = url.protocol === 'https:' ? https : http;
  return new Promise((resolve, reject) => {
    const req = transport.request(
      {
        protocol: url.protocol,
        hostname: url.hostname,
        port: url.port,
        method: options.method,
        path: `${url.pathname}${url.search}`,
        rejectUnauthorized: false,
        headers,
        timeout: options.timeoutMs ?? 30_000,
        signal: options.signal,
      },
      (res) => {
        const chunks: Buffer[] = [];
        res.on('data', (chunk: Buffer) => chunks.push(chunk));
        // A connection dropped mid-body emits 'error' and never 'end'; without this the
        // promise never settles (and a long-lived `codeman mcp` never answers the call).
        res.on('error', reject);
        res.on('end', () => {
          const text = Buffer.concat(chunks).toString('utf-8');
          let json: ApiEnvelope | undefined;
          try {
            json = JSON.parse(text) as ApiEnvelope;
          } catch {
            json = undefined;
          }
          resolve({ status: res.statusCode ?? 0, json, text });
        });
      }
    );
    req.on('timeout', () => req.destroy(new Error(`request timed out after ${options.timeoutMs ?? 30_000} ms`)));
    req.on('error', reject);
    if (bodyText !== undefined) req.write(bodyText);
    req.end();
  });
};

/** One line describing a failed response, for humans. Plain-text guards (401/403/429) have no envelope. */
export function describeFailure(res: ApiResponse): string {
  if (res.json && !res.json.success) {
    return `${res.json.errorCode ?? 'ERROR'}: ${res.json.error ?? 'request failed'} (HTTP ${res.status})`;
  }
  const text = res.text.trim().split('\n')[0] ?? '';
  if (res.status === 401)
    return `HTTP 401 ${text}: the server wants a password (CODEMAN_PASSWORD, or the data dir's .env)`;
  return `HTTP ${res.status}${text ? ` ${text}` : ''}`;
}

// ─────────────────────────────────────────────────────────────────────────────
// Commands
// ─────────────────────────────────────────────────────────────────────────────

export interface AgentIo {
  out: (line: string) => void;
  err: (line: string) => void;
}

export interface AgentDeps {
  ctx: AgentContext;
  request: ApiRequest;
  io: AgentIo;
  json: boolean;
  /** Clock for `seq`; injectable so tests are deterministic. */
  now?: () => number;
}

/** Print `data` as JSON (the `--json` path) — always the envelope's `data`, never a reshaped copy. */
function emitJson(deps: AgentDeps, data: unknown): void {
  deps.io.out(JSON.stringify(data, null, 2));
}

function fail(deps: AgentDeps, message: string, code: number = EXIT.error): number {
  if (deps.json) {
    deps.io.out(JSON.stringify({ success: false, error: message }));
  } else {
    deps.io.err(palette.err(`${GLYPH.fail} ${message}`));
  }
  return code;
}

interface SessionRow {
  id: string;
  name?: string;
  mode?: string;
  status?: string;
  workingDir?: string;
  pid?: number | null;
  parentSessionId?: string | null;
}

/** A full session id (the only form the routes accept); `ls` prints the 8-char prefix. */
const FULL_ID_LENGTH = 36;

/**
 * Shortest prefix that may name a session: the 8-char form `ls` prints, and the floor
 * the server's own resolver uses (`PARENT_SESSION_ID_MIN_PREFIX`, route-helpers.ts).
 */
export const MIN_ID_PREFIX_LENGTH = 8;

/**
 * Turn the id a human typed into the one the routes accept. `ls` prints 8-char
 * prefixes and the routes answer 404 to those (measured live), so anything shorter
 * than a full id resolves through the session list; an ambiguous prefix refuses
 * rather than picking one. Below 8 characters it refuses before the list: "unique"
 * means nothing for `9` — it names whatever session happens to be alone with that
 * first character, and `rm`/`send` would act on it.
 */
export async function resolveSessionId(
  deps: AgentDeps,
  id: string
): Promise<{ id: string } | { error: string; code: number }> {
  if (!id) return { error: 'refusing: empty session id', code: EXIT.refused };
  if (id.length < MIN_ID_PREFIX_LENGTH) {
    return {
      error: `refusing: "${id}" is shorter than ${MIN_ID_PREFIX_LENGTH} characters — use the 8-character id \`agent ls\` prints, or the full id`,
      code: EXIT.refused,
    };
  }
  if (id.length >= FULL_ID_LENGTH) return { id };
  const res = await deps.request(deps.ctx, { method: 'GET', path: '/api/v1/sessions' });
  if (!res.json?.success) return { error: describeFailure(res), code: EXIT.error };
  const matches = ((res.json.data as SessionRow[] | undefined) ?? []).filter((s) => s.id.startsWith(id));
  if (matches.length === 1) return { id: matches[0].id };
  if (matches.length === 0) return { error: `no session starts with "${id}" (see \`agent ls\`)`, code: EXIT.error };
  return { error: `"${id}" is ambiguous: ${matches.map((s) => s.id.slice(0, 13)).join(', ')}`, code: EXIT.error };
}

/** `agent ls` — every session the caller can see, self marked. */
export async function agentLs(deps: AgentDeps): Promise<number> {
  const res = await deps.request(deps.ctx, { method: 'GET', path: '/api/v1/sessions' });
  if (!res.json?.success) return fail(deps, describeFailure(res));
  const sessions = (res.json.data as SessionRow[] | undefined) ?? [];
  if (deps.json) {
    emitJson(
      deps,
      sessions.map((s) => ({ ...s, self: isSelfSession(deps.ctx.selfId, s.id) }))
    );
    return EXIT.ok;
  }
  if (sessions.length === 0) {
    deps.io.out(palette.muted('(no sessions)'));
    return EXIT.ok;
  }
  const rows = sessions.map((s) => [
    isSelfSession(deps.ctx.selfId, s.id) ? '*' : ' ',
    s.id.slice(0, 8),
    s.mode ?? '?',
    s.status ?? '?',
    s.name || s.workingDir || '',
  ]);
  deps.io.out(table([[' ', 'ID', 'MODE', 'STATUS', 'NAME'], ...rows], { gap: 2 }));
  deps.io.out(
    palette.muted(`* = this session (${deps.ctx.selfId.slice(0, 8)}). status is a UI hint, never a sync signal.`)
  );
  return EXIT.ok;
}

export interface SpawnOptions {
  caseName: string;
  mode: string;
  name?: string;
  /** Wait for the composer before returning, where the registry gives the mode a ready mark. */
  ready: boolean;
  timeoutMs: number;
}

/**
 * Agent-scratch label for a case directory a spawn CREATES (the server applies it only
 * when quick-start makes the directory). The Add Case UI offers a recursive delete for
 * such directories, so this header must never ride any other request: mislabelling a
 * real repo there is the one failure in this area that costs actual work.
 */
export const AGENT_ORIGIN_HEADER = { 'X-Codeman-Agent-Origin': 'codeman-agent-cli' } as const;

/**
 * What the mode's TUI draws once its composer can take a prompt, from the CLI registry
 * (`capabilities.composerReadyMark`); undefined means the mode has no readiness wait.
 */
export function composerReadyMark(mode: string): string | undefined {
  return getCli(mode)?.capabilities.composerReadyMark;
}
/** `agent spawn` — quick-start with lineage, then the readiness ladder where the mode has one. */
export async function agentSpawn(deps: AgentDeps, options: SpawnOptions): Promise<number> {
  const body: Record<string, unknown> = {
    caseName: options.caseName,
    mode: options.mode,
    parentSessionId: deps.ctx.selfId,
  };
  if (options.name) body.sessionName = options.name;
  const res = await deps.request(deps.ctx, {
    method: 'POST',
    path: '/api/v1/quick-start',
    body,
    headers: { ...AGENT_ORIGIN_HEADER },
  });
  const data = res.json?.data as { sessionId?: string; caseName?: string; casePath?: string } | undefined;
  if (!res.json?.success || !data?.sessionId) return fail(deps, describeFailure(res));
  const sid = data.sessionId;

  let ready: boolean | undefined;
  let readinessError: string | undefined;
  let dead = false;
  const mark = composerReadyMark(options.mode);
  if (options.ready && mark) {
    const wait = await deps.request(deps.ctx, {
      method: 'GET',
      path: `/api/v1/sessions/${encodeURIComponent(sid)}/wait-output`,
      query: { match: mark, from: 'buffer', timeout: options.timeoutMs },
      timeoutMs: options.timeoutMs + 10_000,
    });
    // A failed readiness call (waiter cap, 400, network) is its own error, not "the
    // composer never showed up": report the real reason instead of the trust-dialog hint.
    if (!wait.json?.success) readinessError = describeFailure(wait);
    else {
      const result = (wait.json.data as { wait?: WaitResult } | undefined)?.wait;
      // A worker that died while we waited is exit 3 like every other wait, not a
      // "composer not seen" timeout that sends the caller looking for a dialog.
      dead = waitExitCode(result) === EXIT.dead;
      ready = !dead && Boolean(result?.matched);
    }
  }

  if (deps.json) {
    emitJson(deps, { ...data, ready, readinessError });
  } else {
    // Human lines go to stderr so `SID=$(codeman agent spawn …)` captures the id alone.
    const say = (line: string) => deps.io.err(line);
    say(palette.ok(`${GLYPH.ok} spawned ${sid} (${options.mode}, case ${data.caseName ?? options.caseName})`));
    if (ready === true) say(palette.muted('  composer up: the worker can take a prompt'));
    if (dead) say(palette.err(`${GLYPH.fail} the worker exited during the readiness wait`));
    if (ready === false && !dead) {
      say(
        palette.warn(
          `${GLYPH.warn} composer not seen within ${options.timeoutMs} ms — read \`agent read ${sid.slice(0, 8)} --tail 2000\` before sending (a startup dialog?)`
        )
      );
    }
    if (readinessError) say(palette.err(`${GLYPH.fail} readiness check failed: ${readinessError}`));
    if (ready === undefined && !readinessError && options.ready) {
      say(
        palette.muted(
          `  ${options.mode} has no readiness mark; give it a moment, then use --match markers to synchronize`
        )
      );
    }
    deps.io.out(sid);
  }
  if (readinessError) return EXIT.error;
  if (dead) return EXIT.dead;
  return ready === false ? EXIT.timeout : EXIT.ok;
}

export interface SendOptions {
  id: string;
  text: string;
  enter: boolean;
  /** `undefined` = fire-and-forget; `true` = default signal set; string = comma list. */
  wait?: string | true;
  timeoutMs?: number;
  clientId?: string;
  seq?: number;
}

/** `agent send` — printable text plus `\r`, exactly-once, optionally blocking on end of turn. */
export async function agentSend(deps: AgentDeps, options: SendOptions): Promise<number> {
  if (isSelfSession(deps.ctx.selfId, options.id)) {
    return fail(deps, `refusing: ${options.id} is me — typing into my own composer is not a message`, EXIT.refused);
  }
  const refusal = inputRefusal(options.text);
  if (refusal) return fail(deps, refusal, EXIT.refused);
  const target = await resolveSessionId(deps, options.id);
  if ('error' in target) return fail(deps, target.error, target.code);
  const body = buildSendBody(options.text, {
    enter: options.enter,
    clientId: options.clientId ?? defaultClientId(deps.ctx.selfId),
    seq: options.seq ?? (deps.now ?? Date.now)(),
    wait: options.wait,
    waitTimeout: options.wait !== undefined ? options.timeoutMs : undefined,
  });
  const res = await deps.request(deps.ctx, {
    method: 'POST',
    path: `/api/v1/sessions/${encodeURIComponent(target.id)}/input`,
    body,
    timeoutMs: (options.timeoutMs ?? 60_000) + 10_000,
  });
  if (!res.json?.success) return fail(deps, describeFailure(res));
  const data = res.json.data as
    | { delivered?: boolean; duplicate?: boolean; buffered?: boolean; dropped?: boolean; wait?: WaitResult }
    | undefined;
  if (deps.json) emitJson(deps, data ?? {});
  // Fire-and-forget to a remote session whose host is asleep (wake-on-LAN): the server
  // holds the chunk and types it once the pane is back (`buffered`), or the chunk was
  // over the wake buffer's cap and is gone (`dropped`). The seq is spent either way,
  // so a retry needs a new one (the default, the clock, gives it that).
  if (data?.dropped) {
    if (!deps.json) {
      deps.io.err(
        palette.err(
          `${GLYPH.fail} dropped: ${target.id}'s host is waking and its input buffer is full — nothing will be typed; send again once it is back`
        )
      );
    }
    return EXIT.error;
  }
  // `delivered:false` without `duplicate` is the route's "the bytes went nowhere":
  // the PTY exited or send-keys hit a dead pane. The field exists so a client does not
  // say "wait longer" when the truth is "restart the worker" — so it is a failure here.
  if (data?.delivered === false && !data.duplicate) {
    if (!deps.json) {
      deps.io.err(
        palette.err(`${GLYPH.fail} not delivered: ${target.id} has no live worker (pane exited) — restart it`)
      );
    }
    return EXIT.dead;
  }
  if (!deps.json) {
    const noEnter = options.enter ? '' : ' (no Enter)';
    if (data?.duplicate) {
      deps.io.out(palette.warn(`${GLYPH.warn} duplicate (clientId/seq already applied): nothing typed`));
    } else if (data?.buffered) {
      deps.io.out(
        palette.ok(
          `${GLYPH.ok} buffered for ${target.id}${noEnter}: its host is asleep; Codeman is waking it and types this once the pane is back`
        )
      );
    } else if (data?.delivered === true) {
      deps.io.out(palette.ok(`${GLYPH.ok} delivered to ${target.id}${noEnter}`));
    } else {
      // Fire-and-forget answers before the write, so there is no delivery report here.
      deps.io.out(palette.ok(`${GLYPH.ok} accepted for ${target.id}${noEnter} (no delivery report without --wait)`));
    }
    if (data?.wait) deps.io.out(describeWait(data.wait));
  }
  if (options.wait === undefined) return EXIT.ok;
  return waitExitCode(data?.wait);
}

function describeWait(wait: WaitResult): string {
  if (wait.signal === 'exit') return palette.err(`${GLYPH.fail} the session exited`);
  if (wait.ended) {
    return palette.err(
      `${GLYPH.fail} the wait ended without an answer: the session went away (dead worker, deleted, or nothing was written)`
    );
  }
  // A timeout is a 200 with `timedOut`, an answer rather than a failure: exit 2 says it,
  // so the line stays neutral instead of looking like an error to whoever reads the log.
  if (wait.timedOut) return palette.muted(`timed out after ${wait.timeoutMs ?? '?'} ms (exit 2)`);
  if (wait.matched !== undefined) {
    return wait.matched
      ? palette.ok(`${GLYPH.ok} matched "${wait.match}"${wait.snippet ? `: ${wait.snippet}` : ''}`)
      : palette.muted('not matched (exit 2)');
  }
  return palette.ok(
    `${GLYPH.ok} signal: ${wait.signal}${wait.immediate ? ' (immediate: current state, not a transition)' : ''}`
  );
}

export interface WaitOptions {
  id: string;
  until?: string;
  match?: string;
  from?: 'buffer' | 'now';
  fresh?: boolean;
  nocase?: boolean;
  timeoutMs: number;
}

/** `agent wait` — a signal (`--until`) or a literal output marker (`--match`). */
export async function agentWait(deps: AgentDeps, options: WaitOptions): Promise<number> {
  if (options.until && options.match)
    return fail(deps, 'use either --until <signals> or --match <marker>, not both', EXIT.refused);
  const target = await resolveSessionId(deps, options.id);
  if ('error' in target) return fail(deps, target.error, target.code);
  const sid = encodeURIComponent(target.id);
  const res = options.match
    ? await deps.request(deps.ctx, {
        method: 'GET',
        path: `/api/v1/sessions/${sid}/wait-output`,
        query: {
          match: options.match,
          from: options.from ?? 'buffer',
          nocase: options.nocase ? 1 : undefined,
          timeout: options.timeoutMs,
        },
        timeoutMs: options.timeoutMs + 10_000,
      })
    : await deps.request(deps.ctx, {
        method: 'GET',
        path: `/api/v1/sessions/${sid}/wait`,
        query: { until: options.until, fresh: options.fresh ? 1 : undefined, timeout: options.timeoutMs },
        timeoutMs: options.timeoutMs + 10_000,
      });
  // A 400 here is the server saying "this mode has no such signal" (until=stop on an
  // external CLI). Passed through, never papered over: the marker path is the answer.
  if (!res.json?.success) return fail(deps, describeFailure(res));
  const data = res.json.data as { wait?: WaitResult; status?: string; limitPaused?: boolean } | undefined;
  if (deps.json) {
    emitJson(deps, data ?? {});
  } else if (data?.wait) {
    deps.io.out(describeWait(data.wait));
    if (data.limitPaused)
      deps.io.out(palette.warn(`${GLYPH.warn} session is paused on a usage limit; a timeout is expected`));
  }
  return waitExitCode(data?.wait);
}

export interface ReadOptions {
  id: string;
  /** Bytes of raw terminal to fetch; ANSI is stripped for humans. */
  tail?: number;
  /** Whole conversation (`context=full`) instead of the last assistant message. */
  full?: boolean;
}

/** `agent read` — the last answer (the route picks the transcript reader or the pane segmenter) or a terminal tail. */
export async function agentRead(deps: AgentDeps, options: ReadOptions): Promise<number> {
  const target = await resolveSessionId(deps, options.id);
  if ('error' in target) return fail(deps, target.error, target.code);
  const sid = encodeURIComponent(target.id);
  if (options.tail !== undefined) {
    const res = await deps.request(deps.ctx, {
      method: 'GET',
      path: `/api/v1/sessions/${sid}/terminal`,
      query: { tail: options.tail },
    });
    if (!res.json?.success) return fail(deps, describeFailure(res));
    const buffer = (res.json.data as { terminalBuffer?: string } | undefined)?.terminalBuffer ?? '';
    if (deps.json) emitJson(deps, res.json.data);
    else deps.io.out(stripAnsi(buffer));
    return EXIT.ok;
  }
  const res = await deps.request(deps.ctx, {
    method: 'GET',
    path: `/api/v1/sessions/${sid}/last-response`,
    query: { context: options.full ? 'full' : undefined },
  });
  if (!res.json?.success) return fail(deps, describeFailure(res));
  const data = res.json.data as
    | { text?: string; timestamp?: string; messages?: Array<{ role: string; text: string }> }
    | undefined;
  if (deps.json) {
    emitJson(deps, data ?? {});
    return EXIT.ok;
  }
  if (options.full && data?.messages) {
    for (const m of data.messages) deps.io.out(`${palette.emph(m.role)}: ${m.text}`);
    return EXIT.ok;
  }
  const text = data?.text ?? '';
  if (!text) {
    deps.io.err(
      palette.muted('(empty: nothing answered yet, or nothing the server could segment as an answer; try --tail 3000)')
    );
    return EXIT.ok;
  }
  deps.io.out(text);
  return EXIT.ok;
}

/** `agent interrupt` — a bare ESC keypress, no Enter, conversation intact. */
export async function agentInterrupt(deps: AgentDeps, options: { id: string }): Promise<number> {
  if (isSelfSession(deps.ctx.selfId, options.id)) return fail(deps, `refusing: ${options.id} is me`, EXIT.refused);
  const target = await resolveSessionId(deps, options.id);
  if ('error' in target) return fail(deps, target.error, target.code);
  const body = buildInterruptBody(defaultClientId(deps.ctx.selfId, 'interrupt'), (deps.now ?? Date.now)());
  const res = await deps.request(deps.ctx, {
    method: 'POST',
    path: `/api/v1/sessions/${encodeURIComponent(target.id)}/input`,
    body,
  });
  if (!res.json?.success) return fail(deps, describeFailure(res));
  if (deps.json) emitJson(deps, res.json.data ?? {});
  else
    deps.io.out(
      palette.ok(
        `${GLYPH.ok} ESC sent to ${target.id} — one Esc does not always land; read the tail before the next prompt`
      )
    );
  return EXIT.ok;
}

/** `agent rm` — delete a session that is provably not this one. */
export async function agentRm(deps: AgentDeps, options: { id: string }): Promise<number> {
  const refusal = deleteRefusal(deps.ctx.selfId, options.id);
  if (refusal) return fail(deps, refusal, EXIT.refused);
  const target = await resolveSessionId(deps, options.id);
  if ('error' in target) return fail(deps, target.error, target.code);
  // The guard again on the RESOLVED id: a prefix that is not me can still resolve
  // to me only if the list is lying, but a delete is the one call worth the paranoia.
  const resolvedRefusal = deleteRefusal(deps.ctx.selfId, target.id);
  if (resolvedRefusal) return fail(deps, resolvedRefusal, EXIT.refused);
  const res = await deps.request(deps.ctx, {
    method: 'DELETE',
    path: `/api/v1/sessions/${encodeURIComponent(target.id)}`,
  });
  if (!res.json?.success) return fail(deps, describeFailure(res));
  if (deps.json) emitJson(deps, res.json.data ?? {});
  else deps.io.out(palette.ok(`${GLYPH.ok} deleted ${target.id} (its case directory stays on disk)`));
  return EXIT.ok;
}

// ─────────────────────────────────────────────────────────────────────────────
// Commander wiring
// ─────────────────────────────────────────────────────────────────────────────

const DEFAULT_WAIT_MS = 60_000;

/** Build deps from the live environment; the guard's message is the only thing a non-session caller sees. */
function liveDeps(json: boolean): AgentDeps | undefined {
  try {
    return {
      ctx: resolveAgentContext(),
      request: httpRequest,
      json,
      io: { out: (line) => console.log(line), err: (line) => console.error(line) },
    };
  } catch (err) {
    if (err instanceof AgentGuardError) {
      console.error(palette.err(`${GLYPH.fail} ${err.message}`));
      return undefined;
    }
    throw err;
  }
}

/** Run a verb with the live transport and turn its exit code into the process exit. */
async function run(json: boolean, verb: (deps: AgentDeps) => Promise<number>): Promise<void> {
  const deps = liveDeps(json);
  if (!deps) {
    process.exitCode = EXIT.refused;
    return;
  }
  try {
    process.exitCode = await verb(deps);
  } catch (err) {
    console.error(palette.err(`${GLYPH.fail} ${getErrorMessage(err)}`));
    process.exitCode = EXIT.error;
  }
}

/** Register `codeman agent …` on the program. */
export function registerAgentCommands(program: Command): Command {
  const agent = program
    .command('agent')
    .description('Talk to other sessions from inside one (any CLI mode): list, spawn, send, wait, read, interrupt, rm');

  agent
    .command('ls')
    .alias('list')
    .description('List sessions; * marks this one')
    .option('--json', 'Machine-readable output')
    .action((options: { json?: boolean }) => run(Boolean(options.json), agentLs));

  agent
    .command('spawn <case>')
    .description(
      'Start a worker session in a case (created if missing) and wait for its composer where the mode draws one'
    )
    .option('-m, --mode <mode>', 'Run mode id, as the Run menu names it', 'claude')
    .option('-n, --name <name>', 'Session name shown in the UI')
    .option('--no-ready', 'Return as soon as the session exists, without the readiness wait')
    .option('-t, --timeout <ms>', 'Readiness budget in ms', String(DEFAULT_WAIT_MS))
    .option('--json', 'Machine-readable output')
    .action(
      (caseName: string, options: { mode: string; name?: string; ready: boolean; timeout?: string; json?: boolean }) =>
        run(Boolean(options.json), (deps) =>
          agentSpawn(deps, {
            caseName,
            mode: options.mode,
            name: options.name,
            ready: options.ready,
            timeoutMs: parsePositiveInt(options.timeout, DEFAULT_WAIT_MS),
          })
        )
    );

  agent
    .command('send <id> <text...>')
    .description(
      'Type a prompt into another session and press Enter (ONE quoted argument, printable text only; a prompt that starts with "-" goes after --: send <id> -- "- fix the bug")'
    )
    .option('-w, --wait', 'Block until end of turn (the default signal set; see --until)')
    .option('-u, --until <signals>', 'Signals to wait for, comma list such as stop,exit (implies --wait)')
    .option('-t, --timeout <ms>', 'Wait budget in ms (with --wait)', String(DEFAULT_WAIT_MS))
    .option('--no-enter', 'Type the text without submitting it')
    .option('--client-id <id>', 'Exactly-once tag (default: one per calling session)')
    .option(
      '--seq <n>',
      'Sequence number for the tag (default: the current epoch ms). Must stay monotonic per client id: a reused or lower value is a silent duplicate, nothing is typed'
    )
    .option('--json', 'Machine-readable output')
    .action(
      (
        id: string,
        words: string[],
        options: {
          wait?: boolean;
          until?: string;
          timeout?: string;
          enter: boolean;
          clientId?: string;
          seq?: string;
          json?: boolean;
        }
      ) =>
        run(Boolean(options.json), (deps) => {
          const prompt = sendPromptFromArgs(words);
          if ('error' in prompt) return Promise.resolve(fail(deps, prompt.error, EXIT.refused));
          return agentSend(deps, {
            id,
            text: prompt.text,
            enter: options.enter,
            wait: options.until ?? (options.wait ? true : undefined),
            timeoutMs: parsePositiveInt(options.timeout, DEFAULT_WAIT_MS),
            clientId: options.clientId,
            seq: options.seq === undefined ? undefined : parsePositiveInt(options.seq, 1, '--seq'),
          });
        })
    );

  agent
    .command('wait <id>')
    .description(
      'Block until a signal (--until) or an output marker (--match) — timeout exits 2, a dead worker exits 3'
    )
    .option(
      '-u, --until <signals>',
      'Comma list: stop,idle,exit,working,blocked (stop needs hook signals for the session, blocked hooks or a dialog Codeman reads off the screen, as for codex; where there are none the server answers 400, passed through)'
    )
    .option(
      '-m, --match <marker>',
      'Literal substring to wait for in the output (ANSI-stripped, no regex). The echo of your own prompt is output too, so never put the marker verbatim in the prompt: ask for it in halves ("print WORKDONE followed by _4711") and wait on the joined form (WORKDONE_4711)'
    )
    .option('--from <where>', 'buffer (scan existing output first, the default) or now', 'buffer')
    .option('--nocase', 'Case-insensitive --match')
    .option('--fresh', 'Require an actual transition (--until only)')
    .option('-t, --timeout <ms>', 'Budget in ms', String(DEFAULT_WAIT_MS))
    .option('--json', 'Machine-readable output')
    .action(
      (
        id: string,
        options: {
          until?: string;
          match?: string;
          from: string;
          nocase?: boolean;
          fresh?: boolean;
          timeout?: string;
          json?: boolean;
        }
      ) =>
        run(Boolean(options.json), (deps) =>
          agentWait(deps, {
            id,
            until: options.until,
            match: options.match,
            from: options.from === 'now' ? 'now' : 'buffer',
            nocase: options.nocase,
            fresh: options.fresh,
            timeoutMs: parsePositiveInt(options.timeout, DEFAULT_WAIT_MS),
          })
        )
    );

  agent
    .command('read <id>')
    .description("Print a session's last answer (as the server reads it for that mode) or, with --tail, its terminal")
    .option('--tail <bytes>', 'Raw terminal tail in bytes, ANSI stripped (works in every mode)')
    .option('--full', 'The whole conversation instead of the last assistant message')
    .option('--json', 'Machine-readable output')
    .action((id: string, options: { tail?: string; full?: boolean; json?: boolean }) =>
      run(Boolean(options.json), (deps) =>
        agentRead(deps, {
          id,
          tail: options.tail === undefined ? undefined : parsePositiveInt(options.tail, 3000, '--tail'),
          full: options.full,
        })
      )
    );

  agent
    .command('interrupt <id>')
    .description('Send a bare ESC to stop the current turn (the conversation survives; deleting would not)')
    .option('--json', 'Machine-readable output')
    .action((id: string, options: { json?: boolean }) =>
      run(Boolean(options.json), (deps) => agentInterrupt(deps, { id }))
    );

  agent
    .command('rm <id>')
    .description('Delete any session except this one (refuses your own id)')
    .option('--json', 'Machine-readable output')
    .action((id: string, options: { json?: boolean }) => run(Boolean(options.json), (deps) => agentRm(deps, { id })));

  return agent;
}