export declare const SYSTEM_SOUNDS: readonly ["Tink", "Glass", "Pop", "Purr", "Ping", "Hero", "Submarine", "Blow", "Bottle", "Frog", "Funk", "Morse", "Sosumi", "Basso"];
export interface SoundConfig {
    /** "off" | "random" | a system sound name. Default: a soft Tink. */
    replyPing: string;
    /** afplay volume 0..1 — pings stay gentle by default. */
    volume: number;
    /** Spoken replies (speak mode) — PERSISTED so updates/respawns never
     *  silently mute the koi again. */
    speak: boolean;
}
export declare function soundConfig(): SoundConfig;
export declare function setSoundConfig(patch: Partial<SoundConfig>): SoundConfig;
/** Transpose a synth recipe by a frequency factor (0.5 = an octave down). */
export declare function transposeRecipe(notes: SynthNote[], factor: number): SynthNote[];
/** Fire-and-forget a named system sound (native on macOS, synthesized
 *  equivalents elsewhere). `pitch` shifts it (0.5 ≈ an octave down — the
 *  ack ping): playback rate on macOS, recipe transposition on synth.
 *  Returns false if unknown. */
export declare function playSystemSound(name: string, volume?: number, pitch?: number): boolean;
/** The soft chime when a reply lands. Honors config; "random" rotates gently. */
export declare function playReplyPing(): void;
/**
 * The "heard you" chime — the SAME configured ping, an octave-ish LOWER,
 * played the moment the koi starts responding. Low tone = working on it,
 * the normal higher tone (playReplyPing) = done.
 */
export declare function playAckPing(): void;
export interface SynthNote {
    /** Scientific pitch ("C4", "F#5", "Bb3") — or give freq directly. */
    note?: string;
    freq?: number;
    /** Duration in ms (20..3000). 0 freq or note "rest" = silence. */
    ms: number;
    wave?: "sine" | "square" | "triangle" | "saw" | "noise";
    /** 0..1, default 0.5. */
    gain?: number;
}
export declare function noteToFreq(note: string): number | null;
/** Render a note sequence to a 16-bit mono WAV buffer. Null = invalid spec. */
export declare function synthWav(notes: SynthNote[]): Buffer | null;
/** Synthesize and play a note sequence. Returns false on invalid spec. */
export declare function playSynth(notes: SynthNote[], volume?: number): boolean;