import type { Token, Tokens, TokensList } from 'marked';

import { lexer } from 'marked';
import wrap from 'word-wrap';

const SINGLE_LINE_CONTENT_WIDTH = 60;
const MULTILINE_DEFAULT_CONTENT_WIDTH = 65;

/**
 * Zapier-platform-schemas is thoroughly documented with Markdown
 * content. This function converts this content into TS/JS block
 * comments (i.e. /** style), preserving even tables and bulleted lists,
 * but adding sensible line wrapping for readability.
 */
export const commentToTsDocString = (comment: string): string => {
  const stripped = comment?.trim();
  if (!stripped) return '';

  const tokens = lexer(stripped);
  const lines = reflowLines(tokens);
  if (lines.length === 1 && lines[0]!.length < SINGLE_LINE_CONTENT_WIDTH) {
    return `/** ${stripped} */\n`;
  }
  const docsLines = lines.map((line) => ` * ${line}`).join('\n');
  return `/**\n${docsLines}\n */\n`;
};

// Exported only for testing purposes.
export const reflowLines = (
  tokens: TokensList,
  { width = MULTILINE_DEFAULT_CONTENT_WIDTH } = {},
): string[] => {
  return tokens.flatMap((t) => reflowToken(t, width));
};

const reflowToken = (token: Token, width: number): string[] => {
  if (isSolitaryLink(token)) {
    const link = token.tokens[0];
    const docLink = `[${link.text}](${link.href})`;
    return [docLink];
  }
  return wrap(token.raw, { width, indent: '', trim: true }).split(/\n/);
};

const isSolitaryLink = (
  token: Token,
): token is Tokens.Paragraph & { tokens: [Tokens.Link] } =>
  token.type === 'paragraph' &&
  token.tokens?.length === 1 &&
  token.tokens[0]?.type === 'link';

export function docStringLines(
  comment: string | undefined,
  trailingContent?: string,
): string[] | undefined {
  if (comment === undefined) {
    return undefined;
  }
  const tokens = lexer(comment);
  return [reflowLines(tokens).join('\n') + (trailingContent ?? '')];
}