/**
 * Template Helpers
 *
 * Handlebars 自定义辅助函数
 */

import Handlebars from 'handlebars';

/**
 * 注册所有自定义辅助函数
 */
export function registerHelpers(): void {
  // 格式化数字（添加千位分隔符）
  Handlebars.registerHelper('formatNumber', (value: number) => {
    return value.toLocaleString();
  });

  // 截断文本
  Handlebars.registerHelper('truncate', (str: string, length: number = 100) => {
    if (str.length <= length) return str;
    return str.substring(0, length) + '...';
  });

  // 格式化日期
  Handlebars.registerHelper('formatDate', (dateStr: string) => {
    const date = new Date(dateStr);
    return date.toLocaleDateString('zh-CN', {
      year: 'numeric',
      month: 'long',
      day: 'numeric',
      hour: '2-digit',
      minute: '2-digit'
    });
  });

  // JSON 序列化（用于内嵌数据）
  Handlebars.registerHelper('json', (context: any) => {
    return JSON.stringify(context);
  });

  // 条件判断
  Handlebars.registerHelper('eq', (a: any, b: any) => {
    return a === b;
  });

  Handlebars.registerHelper('ne', (a: any, b: any) => {
    return a !== b;
  });

  Handlebars.registerHelper('gt', (a: number, b: number) => {
    return a > b;
  });

  Handlebars.registerHelper('lt', (a: number, b: number) => {
    return a < b;
  });
}

/**
 * 渲染模板
 */
export async function renderTemplate(
  templatePath: string,
  data: any
): Promise<string> {
  const templateContent = await Bun.file(templatePath).text();
  const template = Handlebars.compile(templateContent);
  return template(data);
}

export default { registerHelpers, renderTemplate };