/**
 * Handles map with keys and values are of the same type.
 * @extends {BaseTypeHandler}
 * @class
 */
export class MapHandler extends BaseTypeHandler {
	/**
	 * Constructor for MapHandler.
	 * @param {BaseTypeHandler} key_handler - The handler for keys of the map.
	 * @param {BaseTypeHandler} value_handler - The handler for values of the map.
	 */
	constructor(key_handler, value_handler) {
		super();
		this.key_handler = getHandlerObject(key_handler);
		this.value_handler = getHandlerObject(value_handler);
	}

	/**
	 * Gets the size of the serialized map in bytes.
	 * @param {Map} value - The map to calculate the size for.
	 * @returns {number} - The size of the serialized map in bytes.
	 */
	sizeof(value) {
		let res = 4;
		for (const [k, v] of value) {
			res += this.key_handler.sizeof(k);
			res += this.value_handler.sizeof(v);
		}
		return res;
	}

	/**
	 * Serializes the map and writes it to the DataView at the specified offset.
	 * @param {DataView} view - The DataView to write to.
	 * @param {number} offset - The offset to start writing at.
	 * @param {Map} value - The map to be serialized.
	 * @returns {number} - The new offset after serialization.
	 */
	serialize(view, offset, value) {
		view.setUint32(offset, value.size, true);
		offset += 4;
		for (const [k, v] of value) {
			offset = this.key_handler.serialize(view, offset, k);
			offset = this.value_handler.serialize(view, offset, v);
		}
		return offset;
	}

	/**
	 * Deserializes the map from the DataView at the specified offset.
	 * @param {DataView} view - The DataView to read from.
	 * @param {number} offset - The offset to start reading from.
	 * @returns {DeserializedResult} - The deserialized result containing the map and a new offset.
	 */
	deserialize(view, offset) {
		const size = view.getUint32(offset, true);
		offset += 4;
		const res = new Map();
		for (let i = 0; i < size; i += 1) {
			const resk = this.key_handler.deserialize(view, offset);
			const resv = this.value_handler.deserialize(view, resk.offset);
			offset = resv.offset;
			res.set(resk.value, resv.value);
		}
		return new DeserializedResult(res, offset);
	}
}