import type { CheckpointOwnerRegistry } from "./checkpoint-owners.js";
import type { FileCheckpointUnavailableReason, GitCheckpoint, GitRepository, GitRunner, PendingGitCheckpoint, SnapshotIndexLease } from "./types.js";
/** Single spelling of the retained-history ref namespace. Takes an
 *  already-hashed session (`checkpointNamespace(sessionId)`), never a raw id. */
export declare const HISTORY_REF_ROOT = "refs/omp-undo-redo/history/";
export declare function historyRefPrefix(sessionHash: string): string;
export declare function releaseAllPersistentSnapshotIndices(): Promise<void>;
export declare function checkpointNamespace(sessionId: string): string;
export type RepositoryResolution = {
    repository: GitRepository;
} | {
    reason: "git_unavailable" | "not_repository" | "repository_unresolvable";
};
export declare function resolveRepository(git: GitRunner): Promise<RepositoryResolution>;
type SnapshotResult = {
    hash: string;
    snapshotIndexLease?: SnapshotIndexLease;
} | {
    reason: "invalid_head" | "snapshot_failed";
};
export declare function createSnapshotCommit(git: GitRunner, message: string, retainIndex?: boolean): Promise<SnapshotResult>;
interface RefRelease {
    repository: GitRepository;
    ref: string;
    expectedHash: string;
}
export declare function releaseRefs(gitForRepository: (repository: GitRepository) => GitRunner, refs: readonly RefRelease[]): Promise<boolean>;
export declare function releaseCheckpoints(gitForRepository: (repository: GitRepository) => GitRunner, checkpoints: readonly GitCheckpoint[]): Promise<boolean>;
export declare function releaseCheckpoint(git: GitRunner, checkpoint: GitCheckpoint): Promise<boolean>;
export declare function releasePendingCheckpoint(git: GitRunner, pending: Pick<PendingGitCheckpoint, "repository" | "beforeHash" | "beforeRef" | "snapshotIndexLease">): Promise<boolean>;
export type PrepareBeforeTurnResult = {
    status: "git";
    checkpoint: PendingGitCheckpoint;
} | {
    status: "session_only";
    reason: FileCheckpointUnavailableReason;
};
export type FinishAfterTurnResult = {
    status: "git";
    checkpoint: GitCheckpoint;
} | {
    status: "session_only";
    reason: FileCheckpointUnavailableReason;
};
export declare function prepareBeforeTurn(git: GitRunner, sessionId: string, ownerRegistry?: CheckpointOwnerRegistry): Promise<PrepareBeforeTurnResult>;
export declare function finishAfterTurn(git: GitRunner, before: Pick<PendingGitCheckpoint, "repository" | "beforeHash" | "beforeRef" | "snapshotIndexLease">, parentLeafId: string | null, leafId: string | null): Promise<FinishAfterTurnResult>;
export declare function retainCheckpointForResume(git: GitRunner, sessionId: string, checkpoint: GitCheckpoint): Promise<GitCheckpoint>;
export type CheckpointApplyResult = "applied" | "conflict" | "failed";
/** Restores `targetHash`'s content over a worktree that currently matches
 *  `sourceHash`, via a patch instead of a checkout so the index is untouched.
 *
 *  Every flag pins the plumbing contract against the user's own
 *  configuration, each of which otherwise kills restoration outright on that
 *  machine: `diff.noprefix`/`diff.srcPrefix`/`diff.dstPrefix` produce a patch
 *  `git apply -p1` cannot resolve; `color.diff=always` prefixes it with ANSI
 *  escapes ("No valid patches in input"); `diff.external` and textconv
 *  filters replace it with another program's output; `diff.submodule=log`
 *  replaces a gitlink hunk with a commit listing, which invalidates the whole
 *  patch; `diff.context=0` yields hunks `git apply` refuses without
 *  `--unidiff-zero`; `apply.whitespace=error` rejects content git itself
 *  snapshotted. */
export declare function applyCheckpoint(git: GitRunner, sourceHash: string, targetHash: string): Promise<CheckpointApplyResult>;
export {};