/**
 * Public facade and fallback coordinator for embedded-agent compaction.
 */
import { AsyncLocalStorage } from "node:async_hooks";
import { resolveAgentModelFallbackValues } from "../../config/model-input.js";
import { loadSessionEntryReadOnly } from "../../config/sessions/session-accessor.js";
import { projectPublicSessionEntry } from "../../config/sessions/session-entry-projection.js";
import { isAbortError } from "../../infra/abort-signal.js";
import { formatErrorMessage } from "../../infra/errors.js";
import { withPluginRuntimeGenerationScope } from "../../plugins/runtime/generation-scope.js";
import { resolveSessionPinnedHarnessId } from "../../sessions/agent-harness-session-key.js";
import {
  AsyncWorkScope,
  captureAsyncWorkTracker,
  getAsyncWorkSignal,
} from "../../shared/async-work-scope.js";
import { createDeferredCore } from "../../shared/deferred.js";
import { resolveUserPath } from "../../utils.js";
import { prepareSystemAgentRunAdmission } from "../admitted-run-context.js";
import { normalizeOptionalAgentRuntimeId } from "../agent-runtime-id.js";
import {
  resolveAgentDir,
  resolveAgentWorkspaceDir,
  resolveRunModelFallbacksOverride,
  resolveSessionAgentIds,
} from "../agent-scope.js";
import { resolveCliBackendConfig } from "../cli-backends.js";
import { DEFAULT_MODEL, DEFAULT_PROVIDER } from "../defaults.js";
import { coerceToFailoverError } from "../failover-error.js";
import { ensureSelectedAgentHarnessPlugin } from "../harness/runtime-plugin.js";
import { isFallbackSummaryError } from "../model-fallback-attempt.js";
import { resolveModelCandidateChain } from "../model-fallback-candidates.js";
import { runWithModelFallback } from "../model-fallback-runner.js";
import { acquireAgentRunPreparedModelRuntime } from "../prepared-model-runtime.js";
import { resolveProjectKey } from "../project-memory-scope.js";
import { resolveProviderIdForAuth } from "../provider-auth-aliases.js";
import {
  applyAgentRunSessionTargetIdentity,
  resolveAgentRunSessionTarget,
} from "../run-session-target.js";
import { resolveSystemPromptRepoRoot } from "../system-prompt-params.js";
import type {
  CompactEmbeddedAgentSessionParams,
  CompactEmbeddedAgentSessionRuntimeParams,
} from "./compact.types.js";
import { containsRealConversationMessages } from "./compaction-diagnostics.js";
import {
  buildBeforeCompactionHookMetrics,
  estimateTokensAfterCompaction,
  runAfterCompactionHooks,
  runBeforeCompactionHooks,
  runPostCompactionSideEffects,
} from "./compaction-hooks.js";
import { resolveEmbeddedCompactionTarget } from "./compaction-runtime-context.js";
import {
  projectCodexHostTranscriptBytePreflightConfig,
  resolveCompactionRuntimeSelection,
} from "./compaction-runtime-preparation.js";
import { resolveCompactionTimeoutMs } from "./compaction-safety-timeout.js";
import { prepareCompactionSessionAgent } from "./compaction-session-agent.js";
import type { PreparedCompactEmbeddedAgentSessionParams } from "./direct-compaction-preparation.js";
import { compactEmbeddedAgentSessionDirectOnce } from "./direct-compaction.js";
import { readCompactionAccountingRecorder } from "./run/compaction-accounting-bridge.js";
import { prepareEmbeddedSessionActiveProjectKeys } from "./session-prompt-state.js";
import { consumeTranscriptBytePreflightClaim } from "./transcript-byte-preflight-authority.js";
import type { EmbeddedAgentCompactResult } from "./types.js";

export type { CompactEmbeddedAgentSessionParams } from "./compact.types.js";

type CompactEmbeddedAgentSessionParamsWithSessionFile = CompactEmbeddedAgentSessionRuntimeParams & {
  sessionFile: string;
};

function lockedHarnessCompactionFailure(runtime: string): EmbeddedAgentCompactResult {
  return {
    ok: false,
    compacted: false,
    reason: `Model selection is locked to native agent harness "${runtime}"; generic compaction is unavailable.`,
    failure: { reason: "model_selection_locked" },
  };
}

export async function compactNativeCliSession(params: {
  runtime: string | undefined;
  compactParams: CompactEmbeddedAgentSessionParamsWithSessionFile;
  runControlOperation?: (run: () => Promise<void>) => Promise<void>;
}): Promise<EmbeddedAgentCompactResult | undefined> {
  const runtime = normalizeOptionalAgentRuntimeId(params.runtime);
  if (!runtime || params.compactParams.trigger !== "manual") {
    return undefined;
  }
  const backend = resolveCliBackendConfig(runtime, params.compactParams.config, {
    agentId: params.compactParams.agentId,
  });
  if (!backend?.ownsNativeCompaction) {
    return undefined;
  }
  const manualCompaction = backend.manualCompaction;
  if (!manualCompaction) {
    return {
      ok: false,
      compacted: false,
      reason: `CLI backend "${runtime}" owns compaction but does not support manual compaction.`,
    };
  }
  const cliSessionBinding = params.compactParams.cliSessionBinding;
  const cliSessionId = (cliSessionBinding?.sessionId ?? params.compactParams.cliSessionId)?.trim();
  if (!cliSessionId) {
    return {
      ok: false,
      compacted: false,
      reason: `CLI backend "${runtime}" cannot manually compact without a resumable native session.`,
    };
  }
  const { runCliAgent } = await import("../cli-runner.js");
  const runId = `${params.compactParams.runId ?? params.compactParams.sessionId}:native-compact`;
  const sessionAgentId = resolveSessionAgentIds({
    sessionKey: params.compactParams.sessionKey,
    config: params.compactParams.config,
    agentId: params.compactParams.agentId,
  }).sessionAgentId;
  const preparedRunAdmission = prepareSystemAgentRunAdmission(
    params.compactParams.config ?? {},
    runId,
    sessionAgentId,
    "agents.native-compaction",
  );
  try {
    const runControlOperation = async () => {
      await runCliAgent({
        preparedRunAdmission,
        sessionId: params.compactParams.sessionId,
        sessionKey: params.compactParams.sessionKey,
        sessionFile: params.compactParams.sessionFile,
        agentId: params.compactParams.agentId,
        workspaceDir: params.compactParams.workspaceDir,
        cwd: params.compactParams.cwd,
        agentDir: params.compactParams.agentDir,
        config: params.compactParams.config,
        prompt: manualCompaction.buildPrompt(params.compactParams.customInstructions),
        provider: runtime,
        modelProvider: params.compactParams.provider,
        model: params.compactParams.model,
        thinkLevel: params.compactParams.thinkLevel,
        timeoutMs: resolveCompactionTimeoutMs(params.compactParams.config),
        runId,
        cliSessionId,
        ...(cliSessionBinding ? { cliSessionBinding } : {}),
        ...(cliSessionBinding?.authProfileId
          ? { authProfileId: cliSessionBinding.authProfileId }
          : params.compactParams.authProfileId
            ? { authProfileId: params.compactParams.authProfileId }
            : {}),
        ...(params.compactParams.sessionEntry
          ? { sessionEntry: params.compactParams.sessionEntry }
          : {}),
        contextWindow: params.compactParams.sessionEntry?.contextWindow,
        trigger: "manual",
        controlOperation: "compact",
        disableCliLiveSession: true,
        // Compaction rewrites the persisted session behind any idle SDK query. Retire that query
        // after the control turn so the next user turn reloads the compacted conversation.
        cleanupCliLiveSessionOnRunEnd: true,
        allowEmptyAssistantReplyAsSilent: true,
        abortSignal: params.compactParams.abortSignal,
      });
    };
    if (params.runControlOperation) {
      await params.runControlOperation(runControlOperation);
    } else {
      await runControlOperation();
    }
  } catch (err) {
    const signal = params.compactParams.abortSignal;
    if (signal?.aborted && (isAbortError(err) || err === signal.reason)) {
      throw err;
    }
    return {
      ok: false,
      compacted: false,
      reason: `CLI backend "${runtime}" failed to compact its native session: ${formatErrorMessage(err)}`,
    };
  } finally {
    preparedRunAdmission.close();
  }
  return {
    ok: true,
    compacted: true,
    reason: `CLI backend "${runtime}" compacted its native session.`,
  };
}

function hasExplicitCompactionModel(params: CompactEmbeddedAgentSessionParams): boolean {
  return Boolean(params.config?.agents?.defaults?.compaction?.model?.trim());
}

function resolveCompactionFallbacksOverride(
  params: CompactEmbeddedAgentSessionParams,
): string[] | undefined {
  if (params.modelSelectionLocked) {
    return [];
  }
  return (
    params.modelFallbacksOverride ??
    resolveRunModelFallbacksOverride({
      cfg: params.config,
      sessionKey: params.sessionKey,
    })
  );
}

function hasCompactionModelFallbackCandidates(params: CompactEmbeddedAgentSessionParams): boolean {
  const fallbacksOverride = resolveCompactionFallbacksOverride(params);
  const defaultFallbacks = resolveAgentModelFallbackValues(params.config?.agents?.defaults?.model);
  return (fallbacksOverride ?? defaultFallbacks).length > 0;
}

function classifyCompactionFallbackResult(
  result: EmbeddedAgentCompactResult,
  provider: string,
  model: string,
) {
  if (result.ok) {
    return null;
  }
  const reason = result.reason?.trim();
  if (!reason) {
    return null;
  }
  const failureError = Object.assign(new Error(result.failure?.rawError ?? reason), {
    status: result.failure?.status,
    code: result.failure?.code,
  });
  const failoverError = coerceToFailoverError(failureError, { provider, model });
  return failoverError ? { error: failoverError } : null;
}

function fallbackFailureToCompactionResult(err: unknown): EmbeddedAgentCompactResult {
  const reason = isFallbackSummaryError(err) ? err.message : formatErrorMessage(err);
  return {
    ok: false,
    compacted: false,
    reason,
  };
}

/**
 * Core compaction logic without lane queueing.
 * Use this when already inside a session/global lane to avoid deadlocks.
 */
export async function compactEmbeddedAgentSessionDirect(
  paramsInput: CompactEmbeddedAgentSessionRuntimeParams,
): Promise<EmbeddedAgentCompactResult> {
  const paramsBase = applyAgentRunSessionTargetIdentity(paramsInput);
  const memoryTranscript = readCompactionAccountingRecorder(
    paramsBase.contextEngineRuntimeContext,
  )?.memoryTranscript;
  memoryTranscript?.assertActive();
  const runSessionTarget =
    memoryTranscript?.sessionTarget ??
    (await resolveAgentRunSessionTarget({
      ...paramsBase,
      missingSessionKey: "resolve-existing",
    }));
  const entry = loadSessionEntryReadOnly({ ...runSessionTarget, readConsistency: "latest" });
  const lockedHarnessRuntime = resolveSessionPinnedHarnessId(entry);
  const transcriptBytePreflightClaim = consumeTranscriptBytePreflightClaim(
    paramsBase,
    runSessionTarget,
    lockedHarnessRuntime,
  );
  const transcriptBytePreflightAuthority = transcriptBytePreflightClaim?.authority;
  const requestedParams: CompactEmbeddedAgentSessionParamsWithSessionFile = {
    ...paramsBase,
    config: projectCodexHostTranscriptBytePreflightConfig(
      paramsBase.config,
      Boolean(transcriptBytePreflightAuthority),
    ),
    sessionEntry: entry ? projectPublicSessionEntry(entry) : undefined,
    agentHarnessId: lockedHarnessRuntime ?? paramsBase.agentHarnessId,
    modelSelectionLocked: entry?.modelSelectionLocked ?? paramsBase.modelSelectionLocked,
    agentId: runSessionTarget.agentId,
    sessionId: runSessionTarget.sessionId,
    sessionKey: runSessionTarget.sessionKey,
    // SQLite resolves storage identity; the request still owns thread routing.
    sessionTarget: {
      agentId: runSessionTarget.agentId,
      sessionId: runSessionTarget.sessionId,
      sessionKey: runSessionTarget.sessionKey,
      storePath: runSessionTarget.storePath,
      ...(paramsBase.sessionTarget?.threadId !== undefined
        ? { threadId: paramsBase.sessionTarget.threadId }
        : {}),
    },
    sessionFile: runSessionTarget.sessionKey,
  };
  const requestedAgentIds = resolveSessionAgentIds({
    sessionKey: requestedParams.sessionKey,
    config: requestedParams.config,
    agentId: requestedParams.agentId,
  });
  const requestedAgentDir =
    requestedParams.agentDir ??
    resolveAgentDir(requestedParams.config ?? {}, requestedAgentIds.sessionAgentId);
  const requestedWorkspaceDir = resolveUserPath(requestedParams.workspaceDir);
  const canonicalWorkspaceDir = resolveUserPath(
    resolveAgentWorkspaceDir(requestedParams.config ?? {}, requestedAgentIds.sessionAgentId),
  );
  const runtimeSelection = resolveCompactionRuntimeSelection({
    ...requestedParams,
    modelId: requestedParams.model,
    boundHarnessRuntime: requestedParams.agentHarnessId,
    preparedRuntimePlan: requestedParams.runtimePlan,
  });
  // Native control operations reuse the backend's existing authenticated session.
  // Run them before generic model preparation so subscription-only CLI sessions do
  // not incorrectly require an OpenClaw model API credential.
  const nativeCliResult = await compactNativeCliSession({
    runtime: runtimeSelection.selectedHarnessRuntime,
    compactParams: {
      ...requestedParams,
      agentDir: requestedAgentDir,
      workspaceDir: requestedWorkspaceDir,
    },
  });
  if (nativeCliResult) {
    return nativeCliResult;
  }
  if (
    lockedHarnessRuntime &&
    lockedHarnessRuntime !== "openclaw" &&
    !transcriptBytePreflightAuthority
  ) {
    return lockedHarnessCompactionFailure(lockedHarnessRuntime);
  }
  const callerResult = createDeferredCore<EmbeddedAgentCompactResult>();
  const trackOwner = captureAsyncWorkTracker();
  const parentSignal = getAsyncWorkSignal();
  const cancellationSignal =
    requestedParams.abortSignal && parentSignal
      ? AbortSignal.any([requestedParams.abortSignal, parentSignal])
      : (requestedParams.abortSignal ?? parentSignal);
  const work = new AsyncWorkScope();
  let context = work.run(() => AsyncLocalStorage.snapshot());
  let releasePreparedRuntime: (() => Promise<void>) | undefined;
  const runPreparedCompaction = async () => {
    const preparedModelRuntimeLease = await acquireAgentRunPreparedModelRuntime(
      {
        config: requestedParams.config ?? {},
        agentId: requestedAgentIds.sessionAgentId,
        agentDir: requestedAgentDir,
        workspaceDir: requestedWorkspaceDir,
        preserveWorkspaceDirOnRefresh: requestedWorkspaceDir !== canonicalWorkspaceDir,
        ...(requestedParams.allowGatewaySubagentBinding
          ? { allowGatewaySubagentBinding: true }
          : {}),
      },
      {
        abortSignal: requestedParams.abortSignal,
        deriveRuntimePluginSelections: ({ config: admittedConfig, metadataSnapshot }) => {
          const config = projectCodexHostTranscriptBytePreflightConfig(
            admittedConfig,
            Boolean(transcriptBytePreflightAuthority),
          );
          const selected = resolveCompactionRuntimeSelection({
            ...requestedParams,
            config,
            modelId: requestedParams.model,
            boundHarnessRuntime: requestedParams.agentHarnessId,
            preparedRuntimePlan: requestedParams.runtimePlan,
            manifestPlugins: metadataSnapshot,
            allowPluginNormalization: false,
          });
          const pluginPlanCandidates = resolveModelCandidateChain({
            cfg: config,
            agentId: requestedAgentIds.sessionAgentId,
            manifestPlugins: metadataSnapshot,
            allowPluginNormalization: false,
            provider: selected.provider,
            model: selected.modelId,
            requestedRouteResolution: "resolved",
            fallbacksOverride: transcriptBytePreflightAuthority
              ? []
              : resolveCompactionFallbacksOverride({ ...requestedParams, config }),
          });
          return [
            {
              provider: selected.provider,
              modelId: selected.modelId,
              ...(selected.selectedHarnessRuntime
                ? { runtime: selected.selectedHarnessRuntime }
                : {}),
              agentId: requestedAgentIds.sessionAgentId,
            },
            ...pluginPlanCandidates
              .filter(
                (candidate) =>
                  candidate.provider !== selected.provider || candidate.model !== selected.modelId,
              )
              .map((candidate) => ({
                provider: candidate.provider,
                modelId: candidate.model,
                runtime: selected.boundHarnessRuntime,
                agentId: requestedAgentIds.sessionAgentId,
              })),
          ];
        },
      },
    );
    releasePreparedRuntime = () => preparedModelRuntimeLease[Symbol.asyncDispose]();
    try {
      const preparedModelRuntimeOwnerSnapshot = preparedModelRuntimeLease.snapshot;
      const preparedConfig =
        projectCodexHostTranscriptBytePreflightConfig(
          preparedModelRuntimeOwnerSnapshot.config,
          Boolean(transcriptBytePreflightAuthority),
        ) ?? preparedModelRuntimeOwnerSnapshot.config;
      const preparedWorkspaceDir =
        preparedModelRuntimeOwnerSnapshot.workspaceDir ?? requestedWorkspaceDir;
      const repoRoot =
        resolveSystemPromptRepoRoot({
          config: preparedConfig,
          workspaceDir: preparedWorkspaceDir,
          cwd: requestedParams.cwd,
        }) ?? null;
      const projectKey = repoRoot ? await resolveProjectKey(repoRoot) : null;
      const activeProjectKeys = prepareEmbeddedSessionActiveProjectKeys(
        requestedParams.sessionId,
        projectKey,
      );
      const preparedModelRuntime = Object.freeze({
        ...preparedModelRuntimeOwnerSnapshot,
        config: preparedConfig,
        repoRoot,
        projectKey,
        activeProjectKeys,
      });
      // Fallback policy and every attempt consume the same generation as model/auth discovery.
      // A reload may have committed while session targeting was resolved above.
      const params: PreparedCompactEmbeddedAgentSessionParams = {
        ...requestedParams,
        config: preparedConfig,
        agentId: preparedModelRuntime.agentId ?? requestedAgentIds.sessionAgentId,
        agentDir: preparedModelRuntime.agentDir,
        workspaceDir: preparedWorkspaceDir,
        preparedModelRuntime,
        ...(transcriptBytePreflightClaim
          ? {
              transcriptBytePreflightAuthority: true as const,
              ...(transcriptBytePreflightClaim.withCompactionPersistence
                ? {
                    transcriptByteCompactionPersistence:
                      transcriptBytePreflightClaim.withCompactionPersistence,
                  }
                : {}),
            }
          : {}),
      };
      const compactPrepared = async () => {
        if (
          transcriptBytePreflightAuthority ||
          hasExplicitCompactionModel(params) ||
          !hasCompactionModelFallbackCandidates(params)
        ) {
          return await compactEmbeddedAgentSessionDirectOnce(params);
        }
        const resolvedCompactionTarget = resolveEmbeddedCompactionTarget({
          config: params.config,
          provider: params.provider,
          modelId: params.model,
          authProfileId: params.authProfileId,
          modelSelectionLocked: params.modelSelectionLocked,
          defaultProvider: DEFAULT_PROVIDER,
          defaultModel: DEFAULT_MODEL,
        });
        const primaryProvider = resolvedCompactionTarget.provider ?? DEFAULT_PROVIDER;
        const primaryModel = resolvedCompactionTarget.model ?? DEFAULT_MODEL;
        const requestedPrimaryProvider = params.provider?.trim() || DEFAULT_PROVIDER;
        const resolveAuthProvider = (provider: string) =>
          resolveProviderIdForAuth(provider, {
            config: params.config,
            metadataSnapshot: preparedModelRuntime.metadataSnapshot,
          });
        const primaryAuthProviders = new Set(
          [primaryProvider, requestedPrimaryProvider].map(resolveAuthProvider),
        );
        const fallbacksOverride = resolveCompactionFallbacksOverride(params);
        const fallbackAgentId = resolveSessionAgentIds({
          sessionKey: params.sandboxSessionKey ?? params.sessionKey,
          config: params.config,
          agentId: params.sandboxAgentId ?? params.agentId,
        }).sessionAgentId;
        const resolvedPrimaryCandidate = resolveModelCandidateChain({
          cfg: params.config,
          agentId: fallbackAgentId,
          manifestPlugins: preparedModelRuntime.metadataSnapshot,
          provider: primaryProvider,
          model: primaryModel,
          requestedRouteResolution: "resolved",
          fallbacksOverride,
        })[0];
        const fallbackSessionKey =
          params.sandboxSessionKey ?? params.sessionKey ?? params.sessionId;
        const fallbackResult = await runWithModelFallback<EmbeddedAgentCompactResult>({
          cfg: params.config,
          manifestPlugins: preparedModelRuntime.metadataSnapshot,
          provider: primaryProvider,
          model: primaryModel,
          requestedRouteResolution: "resolved",
          runId: params.runId ?? params.sessionId,
          agentDir: params.agentDir,
          agentId: fallbackAgentId,
          sessionId: params.sessionId,
          sessionKey: fallbackSessionKey,
          userLockedAuthProfileId:
            params.authProfileIdSource === "user" ? params.authProfileId : undefined,
          abortSignal: params.abortSignal,
          prepareAgentHarnessRuntime: async ({ provider, model, agentHarnessRuntimeOverride }) => {
            await ensureSelectedAgentHarnessPlugin({
              config: params.config,
              provider,
              modelId: model,
              agentId: fallbackAgentId,
              sessionKey: fallbackSessionKey,
              agentHarnessRuntimeOverride,
              workspaceDir: params.workspaceDir,
              pluginRegistry: preparedModelRuntime.pluginRegistry!,
            });
          },
          fallbacksOverride,
          classifyResult: ({ result, provider, model }) =>
            classifyCompactionFallbackResult(result, provider, model),
          run: async (provider, model) => {
            const isPrimaryCandidate =
              provider === resolvedPrimaryCandidate?.provider &&
              model === resolvedPrimaryCandidate.model;
            const preservesPrimaryAuth =
              isPrimaryCandidate || primaryAuthProviders.has(resolveAuthProvider(provider));
            const authProfileId = preservesPrimaryAuth ? params.authProfileId : undefined;
            return await compactEmbeddedAgentSessionDirectOnce({
              ...params,
              provider,
              model,
              requestedRouteResolution: isPrimaryCandidate ? undefined : "resolved",
              authProfileId,
              authProfileIdSource: preservesPrimaryAuth ? params.authProfileIdSource : undefined,
              // The primary attempt retains its already prepared atomic plan. An
              // actual fallback may change route/auth class and must rebuild it.
              runtimeAuthPlan: isPrimaryCandidate ? params.runtimeAuthPlan : undefined,
              runtimePlan: isPrimaryCandidate ? params.runtimePlan : undefined,
            });
          },
        });
        return fallbackResult.result;
      };
      return await withPluginRuntimeGenerationScope(preparedModelRuntime, () => {
        context = AsyncLocalStorage.snapshot();
        return compactPrepared();
      });
    } catch (err) {
      return fallbackFailureToCompactionResult(err);
    }
  };
  // Logical completion reports promptly; actual attempt work retains this generation.
  void trackOwner(async () => {
    const closeWork = () => context(() => work.beginClose(cancellationSignal?.reason));
    cancellationSignal?.addEventListener("abort", closeWork, { once: true });
    if (cancellationSignal?.aborted) {
      closeWork();
    }
    try {
      callerResult.resolve(await work.track(runPreparedCompaction));
    } catch (error) {
      callerResult.reject(error);
    } finally {
      try {
        await AsyncWorkScope.runWhenAllIdle(
          () => [work],
          () => context(() => work.drain()),
        );
      } finally {
        try {
          await releasePreparedRuntime?.();
        } finally {
          cancellationSignal?.removeEventListener("abort", closeWork);
        }
      }
    }
  }).catch(callerResult.reject);
  return await callerResult.promise;
}

export const testing = {
  compactNativeCliSession,
  containsRealConversationMessages,
  estimateTokensAfterCompaction,
  buildBeforeCompactionHookMetrics,
  prepareCompactionSessionAgent,
  runBeforeCompactionHooks,
  runAfterCompactionHooks,
  runPostCompactionSideEffects,
} as const;