import { Effect, Option } from "effect";
import { Chat, Prompt } from "effect/unstable/ai";
import { SessionStore } from "../context/session.js";
import type { Event as ModelTelemetryEvent } from "../model/model-telemetry.js";
import { AgentError, ResumeMismatch } from "./agent-event.js";
import { type SuspensionCheckpoint } from "./agent-suspension.js";
/**
 * @experimental Session owns model-facing history; a Chat is its live view.
 *
 * The system message is derived from current instructions on every run, so it is never a Session
 * entry. These helpers are the single boundary between the two representations: entries hold
 * conversation only, and a Chat regains the derived system message whenever one is rebuilt.
 */
/** @experimental Drop the derived system message before conversation becomes durable state. */
export declare const conversationOnly: (prompt: Prompt.Prompt) => Prompt.Prompt;
/** @experimental Restore a Session projection into a Chat by prepending the derived system message. */
export declare const withDerivedSystem: (input: {
    readonly system: string | undefined;
    readonly supplemental?: string | undefined;
    readonly projection: Prompt.Prompt;
}) => Prompt.Prompt;
/**
 * @experimental Seed a new Chat from the active Session path.
 *
 * A run continues its Session instead of starting empty, which is what makes a second turn carry the
 * first. Returns undefined when no Session is active or the caller supplied explicit history.
 */
export declare const seedFromSession: (input: {
    readonly activeSession: Option.Option<typeof SessionStore.Service>;
    readonly suppliedHistory: Prompt.RawInput | undefined;
}) => Effect.Effect<Option.Option<Prompt.Prompt>, import("../context/session.js").SessionStoreError>;
/** @experimental Build the Chat a run starts from, preferring an active Session over supplied history. */
export declare const initialChat: (input: {
    readonly sessionHistory: Option.Option<Prompt.Prompt>;
    readonly suppliedHistory: Prompt.RawInput | undefined;
    readonly system: string | undefined;
    readonly supplemental?: string | undefined;
}) => Effect.Effect<Chat.Service>;
/** @internal Validate one resume request against the authoritative Session projection. */
declare const validateResume: (history: Prompt.Prompt, received: import("./agent-event.js").AgentSuspended) => Effect.Effect<SuspensionCheckpoint, ResumeMismatch>;
/** @internal Helpers shared by Session-backed setup without widening the public package facade. */
export declare const SessionHistoryInternal: {
    validateResume: typeof validateResume;
};
export declare const replayModelMessages: (input: {
    readonly activeSession: Option.Option<typeof SessionStore.Service>;
    readonly sessionParentId: string;
    readonly system: string | undefined;
    readonly turn: number;
    readonly sessionError: (turn: number, error: import("../context/session.js").SessionStoreError) => AgentError;
}) => Effect.Effect<ReadonlyArray<Prompt.Message>, AgentError>;
/** @internal Rebuild a resume Chat from Session when no persisted Chat owns the live view. */
export declare const resumeChat: (input: {
    readonly persisted: Chat.Persisted | undefined;
    readonly activeSession: Option.Option<typeof SessionStore.Service>;
    readonly suppliedHistory: Prompt.RawInput | undefined;
}) => Effect.Effect<Chat.Service, import("../context/session.js").SessionStoreError>;
/** @internal Refresh a resumed Session Chat with the system message derived for this Run. */
export declare const refreshResumeSystem: (input: {
    readonly chat: Chat.Service | undefined;
    readonly activeSession: Option.Option<typeof SessionStore.Service>;
    readonly system: string | undefined;
    readonly supplemental?: string | undefined;
}) => Effect.Effect<void, import("../context/session.js").SessionStoreError>;
/**
 * @experimental Reopen the delivery outbox for a recovered checkpoint.
 *
 * Checkpoint telemetry was already observed live and recorded by the host. Restoring it lets an
 * unacknowledged batch be retried, but re-emitting it would replay events the run log already holds
 * and read as a conflicting model call.
 */
export declare const restoreCheckpointTelemetry: (input: {
    readonly session: typeof SessionStore.Service;
    readonly undelivered: Array<ModelTelemetryEvent>;
}) => Effect.Effect<void, import("../context/session.js").SessionStoreError>;
export {};