/**
 * Represents the possible configuration values that can be provided when creating the progress bar text.
 */
interface IProgressBarConfiguration {
  /**
   * Current progress, taken as a decimal (i.e. '0.6' to represent '60%')
   */
  progress?: number;

  /**
   * Total number of ticks in progress bar. Preferably a factor of 100.
   */
  totalTicks?: number;
}

/**
 * Represents concrete configuration values when creating the progress bar text.
 */
interface IProgressBarConfigurationMaterialized extends IProgressBarConfiguration {
  progress: number;
  totalTicks: number;
}

/**
 * Creates a graphical "progress bar"
 * e.g.:  [||||---------------]
 * @param params The configuration parameters for the progress bar
 */
export function createProgressBarText(params: IProgressBarConfiguration): string {
  // Default values
  const defaultParams: IProgressBarConfigurationMaterialized = {
    progress: 0,
    totalTicks: 20,
  };

  // tslint:disable-next-line:prefer-object-spread
  const derived: IProgressBarConfigurationMaterialized = Object.assign({}, defaultParams, params);
  // Ensure it is 0..1
  derived.progress = Math.max(Math.min(derived.progress, 1), 0);

  // This way there is always at least one bar filled in...
  const bars: number = Math.max(Math.floor(derived.progress / (1 / derived.totalTicks)), 1);
  const dashes: number = Math.max(derived.totalTicks - bars, 0);

  // String.prototype.repeat isn't completley supported, but good enough for our purposes
  return `[${"|".repeat(bars)}${"-".repeat(dashes)}]`;
}