/**
 * M5 support — durable block-ledger encoding inside `compaction/summary`.
 *
 * The frozen released-v0 reader (`@deepseek-ai/dsh-session-format-v0-to-v1`)
 * validates every `compaction/summary` payload against an EXACT member
 * allow-list and rejects the first member outside it (issue #141). The six ACP
 * tier/lineage fields used to be written as top-level members, which bricked
 * every pre-upgrade v0 session log the moment the host switched to that
 * reader.
 *
 * The fix moves those fields OUT of the top-level members and INTO the already
 * admitted optional `rawOutput` member, as one text content block carrying a
 * namespaced JSON object. The frozen reader sees only admitted members; the
 * namespaced payload survives losslessly and round-trips back through
 * {@link decodeAcpBlockLedger}. `compaction/*` events are log-only, so this
 * block is inert to the model and to surface derivation — pure durable storage.
 *
 * Decode is strict on the marker/version but lenient per-field, and it NEVER
 * throws: an unknown/absent marker or a future version yields "no ledger data"
 * (the caller falls back to tier-1 reconstruction). Old files and future format
 * generations must degrade, not brick.
 * @module billion-context-dsh/block-ledger
 */
import type { ContentBlock } from '@deepseek-ai/dsh-llm';
/** Marker key identifying an ACP block-ledger payload inside a `compaction/summary` rawOutput text block. */
export declare const ACP_BLOCK_LEDGER_MARKER = "$dshAcpBlockLedger";
/** Current block-ledger payload version. Bump (and add a legacy reader) when the shape changes. */
export declare const ACP_BLOCK_LEDGER_VERSION = 1;
/**
 * The ACP tier/lineage fields carried durably per compressed block so a
 * restarted engine rehydrates the SAME kernel blocks (tier, lineage, coverage)
 * instead of collapsing everything to tier 1, plus B3's verified readings.
 */
export interface AcpBlockLedgerPayload {
    /** Compression tier: 1 (message range), 2 (distills tier-1), 3 (distills tier-2). */
    readonly tier?: 1 | 2 | 3;
    /** The acp-kernel block id (`bN`) created for this transaction. */
    readonly kernelBlockId?: string;
    /** Short block label (kernel `CompressionBlock.topic`). */
    readonly topic?: string;
    /** Durable compaction ids of the blocks distilled into this one. */
    readonly parentBlockIds?: readonly string[];
    /** The kernel block's direct message ids at creation (raw CoreMessage ids). */
    readonly directMessageIds?: readonly string[];
    /** The kernel block's effective message ids at creation (raw CoreMessage ids). */
    readonly effectiveMessageIds?: readonly string[];
    /** B3: acceptance readings already green before compression (e.g. "t0-fastpath 8/8"). */
    readonly verifiedReadings?: readonly string[];
}
/**
 * Encode the block-ledger fields as a single text content block whose text is a
 * namespaced JSON object. The marker + version are always present so decode can
 * recognise the payload; empty/absent fields are omitted to keep it minimal.
 * The offline recovery normalizer reuses this exact encoder so rescued files
 * match what a live engine writes (no shape drift).
 */
export declare function encodeAcpBlockLedger(payload: AcpBlockLedgerPayload): ContentBlock[];
/**
 * Decode + validate the block-ledger payload out of a `compaction/summary`
 * `rawOutput` value read back from the log. Scans the content blocks for the
 * namespaced JSON object, checks the marker/version strictly, accepts each field
 * only if well-typed, and returns `{}` (no ledger data) on ANY problem — it
 * never throws, because old files and future format generations must degrade to
 * the tier-1 fallback rather than brick the session.
 */
export declare function decodeAcpBlockLedger(rawOutput: unknown): AcpBlockLedgerPayload;