import {
  type LoremUnit,
  type LoremFormat,
  FORMAT_PLAIN,
  UNIT_PARAGRAPHS,
  UNIT_SENTENCES,
  UNIT_WORDS,
} from './constants';
import { WORDS } from './constants/words';
import { type Prng } from './lib/generator';
import VeganIpsum from './lib/VeganIpsum';

/**
 * Parameters for generating vegan ipsum text.
 */
export interface VeganIpsumParams {
  /**
   * Number of units to generate (e.g., paragraphs, sentences, or words).
   *
   * @default 1
   */
  count?: number;

  /**
   * Format of the generated text (e.g., plain text or HTML).
   *
   * @default FORMAT_PLAIN
   */
  format?: LoremFormat;

  /**
   * Minimum number of sentences per paragraph.
   *
   * @default 3
   */
  paragraphLowerBound?: number;

  /**
   * Maximum number of sentences per paragraph.
   *
   * @default 7
   */
  paragraphUpperBound?: number;

  /**
   * Custom random number generator.
   */
  random?: Prng;

  /**
   * Minimum number of words per sentence.
   *
   * @default 5
   */
  sentenceLowerBound?: number;

  /**
   * Maximum number of words per sentence.
   *
   * @default 15
   */
  sentenceUpperBound?: number;

  /**
   * Unit type for the generated text (e.g., paragraphs, sentences, or words).
   *
   * @default UNIT_SENTENCES
   */
  units?: LoremUnit;

  /**
   * Custom word list to use for generating text.
   *
   * @default WORDS
   */
  words?: string[];

  /**
   * Suffix to append to the generated text.
   *
   * @default ""
   */
  suffix?: string;
}

/**
 * Generates vegan ipsum text based on the provided parameters.
 *
 * @param {VeganIpsumParams} params - Configuration options for generating vegan ipsum text.
 *
 * @returns {string} Generated vegan ipsum text as a string.
 */
const veganIpsum = ({
  count = 1,
  random,
  format = FORMAT_PLAIN,
  paragraphLowerBound = 3,
  paragraphUpperBound = 7,
  sentenceLowerBound = 5,
  sentenceUpperBound = 15,
  units = UNIT_SENTENCES,
  words = WORDS,
  suffix = '',
}: VeganIpsumParams = {}): string => {
  const options: {
    random?: Prng;
    sentencesPerParagraph: { max: number; min: number };
    words: string[];
    wordsPerSentence: { max: number; min: number };
  } = {
    random,
    sentencesPerParagraph: { max: paragraphUpperBound, min: paragraphLowerBound },
    words,
    wordsPerSentence: { max: sentenceUpperBound, min: sentenceLowerBound },
  };

  const lorem: VeganIpsum = new VeganIpsum(options, format, suffix);

  switch (units) {
    case UNIT_PARAGRAPHS:
      return lorem.generateParagraphs(count);
    case UNIT_SENTENCES:
      return lorem.generateSentences(count);
    case UNIT_WORDS:
      return lorem.generateWords(count);
    default:
      return '';
  }
};

export { veganIpsum, VeganIpsum };