import type { PromptVersion } from '../types/prompts.js';
/** One line of a message diff: kept, added, or removed. */
export interface PromptLineChange {
    /** `=` kept, `+` added, `-` removed. */
    op: '=' | '+' | '-';
    /** The line. */
    text: string;
}
/** How one message, by position, changed. */
export interface PromptMessageDiff {
    /** Its position in the prompt. */
    index: number;
    /** What happened to it. */
    change: 'added' | 'removed' | 'changed' | 'unchanged';
    /** Role before and after, as `system` or `system → user`, or the placeholder it is. */
    role: string;
    /** The content, line by line. */
    lines: PromptLineChange[];
}
/** A field of partials, configuration, or defaults that differs. */
export interface PromptFieldChange {
    /** The field's name. */
    key: string;
    /** Its value before, absent when it was added. */
    before?: unknown;
    /** Its value after, absent when it was removed. */
    after?: unknown;
}
/** What changed between two versions of a prompt. */
export interface PromptDiff {
    /** The prompt. */
    name: string;
    /** The version compared from. */
    from: string;
    /** The version compared to. */
    to: string;
    /** False when the two versions are the same content. */
    changed: boolean;
    /** Every message, by position. */
    messages: PromptMessageDiff[];
    /** Partials added, removed, or changed. */
    partials: PromptFieldChange[];
    /** Configuration fields added, removed, or changed. */
    config: PromptFieldChange[];
    /** Defaults added, removed, or changed. */
    defaults: PromptFieldChange[];
}
/** Line diff by longest common subsequence. Prompts are short, so the quadratic table is cheap. */
export declare function diffLines(before: string, after: string): PromptLineChange[];
/** Compares two versions of a prompt. */
export declare function diffPrompts(from: PromptVersion, to: PromptVersion): PromptDiff;
/** A diff as text, for a terminal, a log, or a pull-request comment. */
export declare function formatPromptDiff(diff: PromptDiff): string;