import { EventEmitter } from "events";
import type { HalType, HalPinDir, HalParamDir, HalValue } from "@linuxcnc-node/types";
import type { HalComponent } from "./component";
/**
 * Base class for HAL pins and parameters.
 *
 * Extends EventEmitter to provide 'change' events when values are modified.
 *
 * @template D - The direction type (HalPinDir for pins, HalParamDir for params)
 *
 * @example
 * ```typescript
 * pin.on('change', (newValue, oldValue) => {
 *   console.log(`Value changed: ${oldValue} -> ${newValue}`);
 * });
 * ```
 */
interface HalItemEvents {
    change: [newValue: HalValue, oldValue: HalValue];
    newListener: [event: string | symbol, listener: (...args: any[]) => void];
    removeListener: [event: string | symbol, listener: (...args: any[]) => void];
}
export declare class HalItem<D extends HalPinDir | HalParamDir> extends EventEmitter<HalItemEvents> {
    private component;
    /**
     * The `nameSuffix` of the item (e.g., "in1", "output").
     */
    readonly name: string;
    /**
     * The HAL data type of the item.
     */
    readonly type: HalType;
    /**
     * The direction of the item (pin direction or parameter direction).
     */
    readonly direction: D;
    constructor(component: HalComponent, nameSuffix: string, type: HalType, direction: D);
    /**
     * Retrieves the current value of this item.
     *
     * @returns The item's value (number or boolean depending on type).
     */
    getValue(): HalValue;
    /**
     * Sets the value of this item.
     *
     * For pins, only applicable to `HAL_OUT` or `HAL_IO` pins.
     * For parameters, only applicable to `HAL_RW` parameters.
     *
     * @param value - The new value for the item.
     * @returns The value that was set.
     * @throws Error if trying to set an `HAL_IN` pin or `HAL_RO` parameter.
     */
    setValue(value: HalValue): HalValue;
}
/**
 * Represents a HAL pin. Instances are returned by `component.newPin()`.
 *
 * @example
 * ```typescript
 * const pin = comp.newPin("output", "float", "out");
 * pin.setValue(123.45);
 * pin.on('change', (newVal, oldVal) => console.log(newVal));
 * ```
 */
export declare class Pin extends HalItem<HalPinDir> {
}
/**
 * Represents a HAL parameter. Instances are returned by `component.newParam()`.
 *
 * @example
 * ```typescript
 * const param = comp.newParam("speed", "float", "rw");
 * param.setValue(100.0);
 * param.on('change', (newVal, oldVal) => console.log(newVal));
 * ```
 */
export declare class Param extends HalItem<HalParamDir> {
}
export {};