@phren/cli/dist/bridge/prompt-once.js

Knowledge layer for AI agents - CLI, MCP server, and data layer

import { createHash } from "node:crypto";
import { z } from "zod";
import { BridgeError } from "./protocol.js";
/** The phone's own name for one message it composed, kept on every attempt to
 * send it. Optional: a client that sends none gets the old, single-attempt behavior. */
export const deliveryIdSchema = z.string().regex(/^[A-Za-z0-9_-]{8,64}$/).optional();
const REMEMBER_MS = 600_000, MAX_ATTEMPTS = 512;
/** Types one phone message at most once per delivery id. A dropped
 * connection (the phone left the app, SSH closed before the reply) made the
 * phone offer Retry for a prompt the Hook had already typed, and the retry
 * typed it a second time. The same id again, for the same pane and text:
 *  - while the first attempt runs, waits for it and answers with its reply;
 *  - after it typed anything, answers with the first reply (or its error),
 *    marked `replayed`, and types nothing;
 *  - after it failed before typing (a stale target, a busy agent), runs again.
 * The same id for another pane or other text is refused. */
export class PromptOnce {
    now;
    attempts = new Map();
    constructor(now = Date.now) {
        this.now = now;
    }
    async run(id, scope, send) {
        if (!id)
            return send(() => { });
        this.prune();
        for (let prior = this.attempts.get(id); prior; prior = this.attempts.get(id)) {
            if (prior.scope !== scope)
                throw new BridgeError(409, "This message id was already used for a different message.");
            const outcome = await prior.done;
            // One that failed before typing was removed; look again (nothing, or a newer attempt).
            if ("error" in outcome && !prior.typed)
                continue;
            if ("error" in outcome)
                throw outcome.error;
            return { ...outcome.result, replayed: true };
        }
        let finish;
        const attempt = { scope, typed: false, done: new Promise(resolve => { finish = resolve; }), at: this.now() };
        this.attempts.set(id, attempt);
        try {
            const result = await send(() => { attempt.typed = true; });
            finish({ result });
            return result;
        }
        catch (error) {
            if (!attempt.typed && this.attempts.get(id) === attempt)
                this.attempts.delete(id);
            finish({ error });
            throw error;
        }
    }
    prune() {
        const cutoff = this.now() - REMEMBER_MS;
        for (const [id, attempt] of this.attempts)
            if (attempt.at < cutoff)
                this.attempts.delete(id);
        while (this.attempts.size >= MAX_ATTEMPTS)
            this.attempts.delete(this.attempts.keys().next().value);
    }
}
/** What a delivery id is bound to: the pane, its agent and the exact text.
 * Not the conversation: a first message that started one is retried against
 * the new conversation's target and must still find its first attempt.
 * Hashed so the table never holds the prompt. */
export function promptScope(target, text) {
    const { server, workspace, tab, pane, source } = target;
    return createHash("sha256").update(JSON.stringify([server, workspace, tab, pane, source, text])).digest("hex");
}