promptTemplate.ts

/**
 * Tagged template for conditional sections with headers.
 * Usage:
 * - section()`Template content here` (basic template)
 * - section({ header: 'Title', condition: true })`Template content here` (with header)
 */
export const prompt = (options: { header?: string; condition?: boolean } = {}) => {
  return (strings: TemplateStringsArray, ...values: (string | number | undefined | null)[]): string => {
    const { header, condition = true } = options;

    if (!condition) {
      return '';
    }

    // Build the content from template literal with full cleanup
    const content = strings
      .reduce((result, str, i) => {
        const value = values[i];
        const stringValue = value !== undefined && value !== null ? String(value) : '';
        return result + str + stringValue;
      }, '')
      .replace(/\n\s*\n\s*\n/g, '\n\n') // Collapse multiple empty lines to double newlines
      .replace(/^\s+|\s+$/g, '') // Trim leading/trailing whitespace
      .replace(/[ \t]+/g, ' ') // Normalize spaces but preserve newlines
      .replace(/\n /g, '\n') // Remove spaces after newlines
      .trim();

    if (!content) {
      return '';
    }

    if (header) {
      return `
==== ${header} ====
${content}
==== End of ${header} ====
`;
    }

    return content;
  };
};