/**
 * The Apso co-author git trailer. Appended to commits that include
 * Apso-generated work so Apso is credited as a co-author.
 */
export declare const APSO_COAUTHOR_TRAILER = "Co-authored-by: Apso <bot@apso.ai>";
/**
 * Relative path (from the repo top-level) where the managed hook is installed.
 * Modern git resolves a relative `core.hooksPath` from the repository root.
 */
export declare const APSO_HOOKS_DIR = ".apso/hooks";
/**
 * Builds the `prepare-commit-msg` bash script that appends the Apso co-author
 * trailer to commits that touch Apso-generated paths.
 *
 * Pure function (no side effects) so it can be unit-tested directly.
 *
 * Behaviour of the generated script:
 * - Skips merge/squash commits (`$2` is `merge` or `squash`).
 * - Honors the `APSO_NO_COAUTHOR=1` opt-out.
 * - Only acts when the staged changes include an Apso-generated path
 *   (a path segment named `autogen/`).
 * - Adds the trailer idempotently via `git interpret-trailers`, which handles
 *   trailer-block formatting + dedupe and coexists with other `Co-authored-by`
 *   trailers (e.g. Claude).
 */
export declare function buildCoAuthorHookScript(): string;
export interface InstallCoAuthorHookOptions {
    /** When true, skip installation (e.g. `.apsorc` set `coAuthor: false`). */
    disabled?: boolean;
}
export interface InstallCoAuthorHookResult {
    installed: boolean;
    reason?: "disabled" | "not-a-git-repo" | "custom-hookspath" | "error";
}
/**
 * Installs the Apso co-author `prepare-commit-msg` hook into a project.
 *
 * Best-effort: never throws. Callers can log the result.
 *
 * - Respects the `disabled` option and the `APSO_NO_COAUTHOR=1` env opt-out.
 * - No-ops (returns `not-a-git-repo`) outside a git work tree.
 * - Writes `<projectRoot>/.apso/hooks/prepare-commit-msg` (mode 0755).
 * - Sets the repo-local `core.hooksPath` to `.apso/hooks` when unset; leaves it
 *   alone (and reports success) when it's already `.apso/hooks`; refuses to
 *   clobber a custom `core.hooksPath` (husky etc.) and reports
 *   `custom-hookspath` so the caller can guide the user.
 */
export declare function installCoAuthorHook(projectRoot: string, opts?: InstallCoAuthorHookOptions): InstallCoAuthorHookResult;