// The step SHAPE lives in contracts/ so the public API vocabulary can be stated in terms of it

// without depending on core/; re-exported here for this module's existing consumers.

import type { DaemonBatchStep } from '@agent-device/contracts/command';

import {

type DaemonRequest,

type DaemonResponse,

type ResponseLevel,

isNonDefaultResponseLevel,

} from '@agent-device/kernel/contracts';

import { AppError, asAppError, type DaemonError } from '@agent-device/kernel/errors';

import { isRecord } from '@agent-device/kernel/record';

import {

DEFAULT_BATCH_MAX_STEPS,

assertBatchStepCount,

isValidBatchMaxSteps,

parseBatchStepRuntime,

} from '@agent-device/contracts/command';

import {

BATCH_DAEMON_STEP_KEYS,

INHERITED_PARENT_FLAG_KEYS,

assertBatchRuntimeCommandAllowed,

normalizeBatchCommandName,

} from './batch-policy.ts';

import { resolveCommandRecordingEffect } from './registry.ts';

const batchAllowedStepKeys = new Set<string>(BATCH_DAEMON_STEP_KEYS);

export type BatchFlags = Record<string, unknown> & {

batchOnError?: 'stop';

batchMaxSteps?: number;

batchSteps?: DaemonBatchStep[];

};

export type BatchRequest = Omit<DaemonRequest, 'flags'> & {

flags?: BatchFlags | Record<string, unknown>;

};

/**

* What the batch runner knows about a step's place in its plan. The daemon uses the remaining

* commands to derive platform readiness policy; it never reaches the wire.

*/

export type BatchStepContext = Readonly<{

stepNumber: number;

totalSteps: number;

/** The steps still ahead, in the shape their handlers will read. */

remainingSteps: readonly Readonly<{

command: string;

positionals: readonly string[];

flags: Readonly<Record<string, unknown>>;

input?: Readonly<Record<string, unknown>>;

}>[];

}>;

export type BatchInvoke = (req: BatchRequest, context: BatchStepContext) => Promise<DaemonResponse>;

export type NormalizedBatchStep = {

command: string;

positionals: string[];

input?: Record<string, unknown>;

flags: Record<string, unknown>;

runtime?: DaemonRequest['runtime'];

};

export type BatchStepResult = {

step: number;

command: string;

ok: true;

data: Record<string, unknown>;

durationMs: number;

};

export type BatchRunResult = Record<string, unknown> & {

total: number;

executed: number;

totalDurationMs: number;

results: BatchStepResult[];

};

export type BatchRunResponse =

| {

ok: true;

data: BatchRunResult;

}

| Extract<DaemonResponse, { ok: false }>;

export async function runBatch(

req: BatchRequest,

sessionName: string,

invoke: BatchInvoke,

): Promise<BatchRunResponse> {

const flags = readBatchFlags(req.flags);

const batchOnError = flags?.batchOnError ?? 'stop';

if (batchOnError !== 'stop') {

return batchErrorResponse('INVALID_ARGS', `Unsupported batch on-error mode: ${batchOnError}.`);

}

const batchMaxSteps = flags?.batchMaxSteps ?? DEFAULT_BATCH_MAX_STEPS;

if (!isValidBatchMaxSteps(batchMaxSteps)) {

return batchErrorResponse(

'INVALID_ARGS',

`Invalid batch max-steps: ${String(flags?.batchMaxSteps)}`,

);

}

try {

const steps = validateAndNormalizeBatchSteps(flags?.batchSteps, batchMaxSteps);

const startedAt = Date.now();

const partialResults: BatchStepResult[] = [];

for (const [index, step] of steps.entries()) {

const stepResponse = await runBatchStep(req, sessionName, step, invoke, {

stepNumber: index + 1,

totalSteps: steps.length,

remainingSteps: steps.slice(index + 1).map((remaining) => ({

command: remaining.command,

positionals: remaining.positionals,

flags: remaining.flags,

...(remaining.input === undefined ? {} : { input: remaining.input }),

})),

});

if (!stepResponse.ok) {

return batchStepFailure(stepResponse, step, {

executedSteps: steps.slice(0, index),

total: steps.length,

partialResults,

});

}

partialResults.push(stepResponse.result);

}

const data: BatchRunResult = {

total: steps.length,

executed: steps.length,

totalDurationMs: Date.now() - startedAt,

results: partialResults,

};

return {

ok: true,

data,

};

} catch (error) {

const appErr = asAppError(error);

return batchErrorResponse(appErr.code, appErr.message, appErr.details);

}

}

type BatchStepFailure = Extract<Awaited<ReturnType<typeof runBatchStep>>, { ok: false }>;

function batchStepFailure(

stepResponse: BatchStepFailure,

step: NormalizedBatchStep,

progress: {

executedSteps: readonly NormalizedBatchStep[];

total: number;

partialResults: BatchStepResult[];

},

): Extract<BatchRunResponse, { ok: false }> {

const { error } = stepResponse;

return {

ok: false,

error: {

code: error.code,

message: `Batch failed at step ${stepResponse.step} (${step.command}): ${error.message}`,

hint: error.hint,

diagnosticId: error.diagnosticId,

logPath: error.logPath,

...(error.retriable === undefined ? {} : { retriable: error.retriable }),

...(error.supportedOn === undefined ? {} : { supportedOn: error.supportedOn }),

details: {

...(error.details ?? {}),

...(progress.executedSteps.some(stepMutatesApp) ? { dispatched: 'unknown' } : {}),

step: stepResponse.step,

command: step.command,

positionals: step.positionals,

executed: progress.executedSteps.length,

total: progress.total,

partialResults: progress.partialResults,

},

},

};

}

/** A batch that executed a mutating step cannot promise that a resend repeats nothing. */

function stepMutatesApp(step: NormalizedBatchStep): boolean {

return resolveCommandRecordingEffect(step) === 'mutates-app';

}

export function validateAndNormalizeBatchSteps(

steps: unknown,

maxSteps: number,

): NormalizedBatchStep[] {

if (!Array.isArray(steps) || steps.length === 0) {

throw new AppError('INVALID_ARGS', 'batch requires a non-empty batchSteps array.');

}

assertBatchStepCount(steps.length, maxSteps);

const normalized: NormalizedBatchStep[] = [];

for (let index = 0; index < steps.length; index += 1) {

const step = steps[index];

if (!isRecord(step)) {

throw new AppError('INVALID_ARGS', `Invalid batch step at index ${index}.`);

}

const unknownKeys = Object.keys(step).filter((key) => !batchAllowedStepKeys.has(key));

if (unknownKeys.length > 0) {

const fields = unknownKeys.map((key) => `"${key}"`).join(', ');

throw new AppError(

'INVALID_ARGS',

`Batch step ${index + 1} has unknown field(s): ${fields}. Allowed fields: command, positionals, input, flags, runtime.`,

);

}

const command = normalizeBatchCommandName(step.command);

if (!command) {

throw new AppError('INVALID_ARGS', `Batch step ${index + 1} requires command.`);

}

assertBatchRuntimeCommandAllowed(command, index + 1);

if (step.positionals !== undefined && !Array.isArray(step.positionals)) {

throw new AppError('INVALID_ARGS', `Batch step ${index + 1} positionals must be an array.`);

}

const positionals = (step.positionals ?? []) as unknown[];

if (positionals.some((value) => typeof value !== 'string')) {

throw new AppError(

'INVALID_ARGS',

`Batch step ${index + 1} positionals must contain only strings.`,

);

}

if (step.flags !== undefined && !isRecord(step.flags)) {

throw new AppError('INVALID_ARGS', `Batch step ${index + 1} flags must be an object.`);

}

if (step.input !== undefined && !isRecord(step.input)) {

throw new AppError('INVALID_ARGS', `Batch step ${index + 1} input must be an object.`);

}

normalized.push({

command,

positionals: positionals as string[],

input: step.input as Record<string, unknown> | undefined,

flags: (step.flags ?? {}) as Record<string, unknown>,

runtime: parseBatchStepRuntime(step.runtime, index + 1),

});

}

return normalized;

}

function buildBatchStepFlags(

parentFlags: BatchFlags | Record<string, unknown> | undefined,

stepFlags: DaemonBatchStep['flags'] | Record<string, unknown> | undefined,

): BatchFlags {

const {

batchSteps: _batchSteps,

batchOnError: _batchOnError,

batchMaxSteps: _batchMaxSteps,

...merged

} = stepFlags ?? {};

return mergeParentFlags(readBatchFlags(parentFlags), merged as BatchFlags);

}

export function mergeParentFlags<TFlags extends Record<string, unknown>>(

parentFlags: BatchFlags | Record<string, unknown> | undefined,

childFlags: TFlags,

): TFlags {

const parentRecord = readBatchFlags(parentFlags) ?? {};

const childRecord = childFlags as Record<string, unknown>;

for (const key of INHERITED_PARENT_FLAG_KEYS) {

if (childRecord[key] === undefined && parentRecord[key] !== undefined) {

childRecord[key] = parentRecord[key];

}

}

return childFlags;

}

// Phase 4 (agent-cost) batch-step elision. When a non-default response level is

// requested for the whole batch, INTERMEDIATE steps are forced to `digest` so a

// multi-step run collapses tokens, while the FINAL step keeps the requested

// level. With no responseLevel (or `default`) this is a no-op, so the per-step

// meta is passed through unchanged — byte-identical to today (Maestro `.ad`

// recompare safe).

function batchStepResponseLevel(

requested: ResponseLevel | undefined,

isFinalStep: boolean,

): ResponseLevel | undefined {

if (!isNonDefaultResponseLevel(requested)) return requested;

return isFinalStep ? requested : 'digest';

}

function batchStepMeta(meta: BatchRequest['meta'], isFinalStep: boolean): BatchRequest['meta'] {

const requested = meta?.responseLevel;

const stepLevel = batchStepResponseLevel(requested, isFinalStep);

if (stepLevel === requested) return meta;

return { ...meta, responseLevel: stepLevel };

}

async function runBatchStep(

req: BatchRequest,

sessionName: string,

step: NormalizedBatchStep,

invoke: BatchInvoke,

context: BatchStepContext,

): Promise<

| { ok: true; step: number; result: BatchStepResult }

| {

ok: false;

step: number;

error: DaemonError;

}

> {

const { stepNumber, totalSteps } = context;

const isFinalStep = stepNumber === totalSteps;

const stepStartedAt = Date.now();

const stepFlags = buildBatchStepFlags(req.flags, step.flags);

if (stepFlags.session === undefined) {

stepFlags.session = sessionName;

}

const response = await invoke(

{

token: req.token,

session: sessionName,

command: step.command,

positionals: step.positionals,

input: step.input,

flags: stepFlags,

runtime: step.runtime === undefined ? req.runtime : step.runtime,

meta: batchStepMeta(req.meta, isFinalStep),

},

context,

);

const durationMs = Date.now() - stepStartedAt;

if (!response.ok) {

return { ok: false, step: stepNumber, error: response.error };

}

return {

ok: true,

step: stepNumber,

result: {

step: stepNumber,

command: step.command,

ok: true,

data: response.data ?? {},

durationMs,

},

};

}

function readBatchFlags(

flags: BatchFlags | Record<string, unknown> | undefined,

): BatchFlags | undefined {

return flags as BatchFlags | undefined;

}

function batchErrorResponse(

code: string,

message: string,

details?: Record<string, unknown>,

): Extract<DaemonResponse, { ok: false }> {

return {

ok: false,

error: { code, message, ...(details ? { details } : {}) },

};

}