/**
 * Task Validator - Validation logic for task operations
 * @requirement REQ-V2-003 - Task validation
 *
 * Provides validation for:
 * - State transitions
 * - State history integrity
 * - Queue and file consistency
 */
import { type WorkflowState } from '@shadel/workflow-core';
import type { Task as QueueTask } from './task-queue.js';
import type { TaskFileData } from './task-file-sync.js';
/**
 * Validation result
 */
export interface ValidationResult {
    valid: boolean;
    error?: string;
    source?: 'queue' | 'file';
}
/**
 * Task Validator - Validation logic for task operations
 *
 * Responsibilities:
 * - Validate state transitions
 * - Validate state history integrity
 * - Validate queue and file consistency
 */
export declare class TaskValidator {
    /**
     * Valid state transitions map
     */
    private readonly validTransitions;
    /**
     * Validate state transition
     *
     * @param currentState - Current workflow state
     * @param newState - New workflow state
     * @throws Error if transition is invalid
     */
    validateStateTransition(currentState: WorkflowState, newState: WorkflowState): Promise<void>;
    /**
     * Validate state history integrity
     *
     * Checks for:
     * - State regression (going backwards)
     * - State skipping (unless explicitly allowed)
     * - Invalid states in history
     *
     * @param task - Task from queue or file
     * @returns Validation result
     */
    validateStateHistory(task: QueueTask | TaskFileData): Promise<ValidationResult>;
    /**
     * Validate both queue and file data
     *
     * Validates:
     * - Queue data integrity
     * - File data integrity
     * - Consistency between queue and file
     *
     * @param queueTask - Task from queue
     * @param fileData - Task from file
     * @returns Validation result
     */
    validateBoth(queueTask: QueueTask, fileData: TaskFileData): Promise<ValidationResult>;
    /**
     * Get valid transitions from a state
     *
     * @param state - Current state
     * @returns Array of valid next states
     */
    getValidTransitions(state: WorkflowState): WorkflowState[];
}