import {DataContainerInterface} from './data-container-interface';

/**
 * Setting for shared row optimization.
 * - False/undefined indicates that unique row objects should be used (default).
 * - True indicates that a single temporary row object should be created and used without extra allocations.
 * - A DataRow object indicates that the row should be used as a temporary shared row.
 * When used, the content of the shared row isn't preserved between calls.
 */
export type SharedRowOptions = DataRow | boolean | undefined;

/**
 * Return type for createSharedRow:
 * - DataRow object that should be used as shared row.
 * - Falsy values indicate that shared row object shouldn't be used.
 */
export type SharedRowOptionsResult = DataRow | false | undefined;

export class DataRow {
  /**
   * Creates new DataRow.
   * @param dataContainer Data container where data is stored. Can be initialized with null for shared rows.
   * @param rowIndex Index of a row in the data container.
   */
  constructor(dataContainer: DataContainerInterface | null, rowIndex: number);

  /**
 * Conditionally creates a DataRow object.
 * @param sharedRowDesc Accepts forllowing options:
 * - true indicates that new DataRow should be created.
 * - falsy value or a DataRow object is passed through without any change.
 * @returns A new DataRow object or unchanged input argument.
 */
  static createSharedRow(sharedRowDesc: SharedRowOptions): SharedRowOptionsResult;

  /**
   * Returns the value stored at the specified index in the row.
   * @param index Index of the requested field in the row.
   * @returns Value at the index.
   */
  valueAt(index: number): any;

  /**
   * Returns the row represented as an array.
   * @returns The row represented as an array.
   */
  values(): any[];

  /**
   * Setup a row object. The method is used by shared rows to prevent excessive allocations.
   * @param dataContainer Data container.
   * @param rowIndex Index of a row in the data container.
   */
  setSource(dataContainer: DataContainerInterface, rowIndex: number): void;

  /**
   * Creates a new array populated with the results of calling the provided function
   * on every element of the row.
   * @param func The callback is called with the following arguments:
   * - elem: The current element being processed in the row.
   * - index: The index of the current element being processed in the row.
   * @returns A new array with each element being the result of the func callback.
   */
  map(func: (elem: any, index: number) => any): any[];
}