/**
 * Converts an absolute filesystem path to the session directory name format
 * used by pi: strips the leading `/`, replaces all remaining `/` with `-`,
 * and wraps the result in `--`.
 *
 * Example: `/home/alice/Code/my-project` → `--home-alice-Code-my-project--`
 */
export declare function cwdToSessionDirName(cwd: string): string;
/**
 * Reverses `cwdToSessionDirName`: strips the leading and trailing `--`,
 * prepends a `/`, and replaces `-` back with `/`.
 *
 * Note: this is a best-effort reversal. Since both `/` and `-` in the
 * original path both become `-` in the encoded form, the decoded path is
 * ambiguous when the original path contains literal `-` segments. In
 * practice vmpi only needs to decode the VM-side name (`--workspace--`),
 * which is unambiguous.
 *
 * Example: `--home-alice-Code-my-project--` → `/home/alice/Code/my-project`
 */
export declare function sessionDirNameToCwd(dirName: string): string;
/**
 * Copies the host's session directory for `hostCwd` into the `--workspace--`
 * slot inside `piConfigDir` (which is a temp snapshot of the host's ~/.pi).
 * This lets pi running at `/workspace` inside the VM find prior sessions.
 *
 * We copy rather than symlink because the host's `--workspace--` symlink may
 * point to an absolute host path that has no meaning inside the guest.
 *
 * If no matching session directory exists on the host, this is a no-op.
 * If `hostCwd` is already `/workspace`, the slot is already in the right place.
 */
export declare function prepareSessionsForVm(hostCwd: string, piConfigDir: string): void;
/**
 * Merges sessions written to the `--workspace--` slot back into the host
 * CWD session directory, then removes the `--workspace--` copy.
 *
 * Pi appends to session files in-place when continuing a session, so the VM
 * copy of an existing file may be larger than the host's original. Files are
 * moved when new (not on host) or replaced when the VM copy is larger (new
 * content was appended). Same-size copies -- unchanged files that were only
 * mirrored for context -- are left on the host as-is.
 *
 * `snapshotDir` is the temporary pi config snapshot that the VM wrote to
 * (i.e. where `--workspace--` lives). `hostPiConfigDir` is the real host
 * pi config dir (i.e. `~/.pi`) where sessions should be written back.
 * When omitted, `hostPiConfigDir` defaults to `snapshotDir` (used in tests).
 *
 * This is a no-op when `hostCwd` is `/workspace` or if no `--workspace--`
 * directory exists.
 */
export declare function collectSessionsFromVm(hostCwd: string, snapshotDir: string, hostPiConfigDir?: string): void;