feat: csv front matter

src/components/utils/csv-loader.ts

@@ -1,22 +1,61 @@
 import { parse } from 'csv-parse/browser/esm/sync';
+import yaml from 'js-yaml';
 
 /**
  * 全局缓存已加载的 CSV 内容
  */
 const csvCache = new Map<string, Record<string, string>[]>();
 
+/**
+ * 解析 front matter
+ * @param content 包含 front matter 的内容
+ * @returns 解析结果，包含 front matter 和剩余内容
+ */
+function parseFrontMatter(content: string): { frontmatter?: JSONObject; remainingContent: string } {
+  // 检查是否以 --- 开头
+  if (!content.trim().startsWith('---')) {
+    return { remainingContent: content };
+  }
+
+  // 分割内容
+  const parts = content.split(/(?:^|\n)---\s*\n/);
+  
+  // 至少需要三个部分：空字符串、front matter、剩余内容
+  if (parts.length < 3) {
+    return { remainingContent: content };
+  }
+
+  try {
+    // 解析 YAML front matter
+    const frontmatterStr = parts[1].trim();
+    const frontmatter = yaml.load(frontmatterStr) as JSONObject;
+    
+    // 剩余内容是第三部分及之后的所有内容
+    const remainingContent = parts.slice(2).join('---\n').trimStart();
+    
+    return { frontmatter, remainingContent };
+  } catch (error) {
+    console.warn('Failed to parse front matter:', error);
+    return { remainingContent: content };
+  }
+}
+
 /**
  * 加载 CSV 文件
  * @template T 返回数据的类型，默认为 Record<string, string>
  */
-export async function loadCSV<T = Record<string, string>>(path: string): Promise<T[]> {
+export async function loadCSV<T = Record<string, string>>(path: string): Promise<CSV<T>> {
   if (csvCache.has(path)) {
-    return csvCache.get(path)! as T[];
+    return csvCache.get(path)! as CSV<T>;
   }
 
   const response = await fetch(path);
   const content = await response.text();
-  const records = parse(content, {
+  
+  // 解析 front matter
+  const { frontmatter, remainingContent } = parseFrontMatter(content);
+  
+  const records = parse(remainingContent, {
     columns: true,
     comment: '#',
     trim: true,
@@ -24,6 +63,36 @@ export async function loadCSV<T = Record<string, string>>(path: string): Promise
   });
 
   const result = records as Record<string, string>[];
+  // 添加 front matter 到结果中
+  const csvResult = result as CSV<T>;
+  if (frontmatter) {
+    csvResult.frontmatter = frontmatter;
+  }
+  
   csvCache.set(path, result);
-  return result as T[];
+  return csvResult;
 }
+
+type JSONData = JSONArray | JSONObject | string | number | boolean | null;
+interface JSONArray extends Array<JSONData> {}
+interface JSONObject extends Record<string, JSONData> {}
+
+export type CSV<T> = T[] & {
+  frontmatter?: JSONObject;
+}
+
+export function processVariables<T extends JSONObject> (body: string, currentRow: T, csv: CSV<T>, filtered?: T[], remix?: boolean): string {
+  const rolled = filtered || csv;
+
+  function replaceProp(key: string) {
+    const row = remix ?
+        rolled[Math.floor(Math.random() * rolled.length)] :
+        currentRow;
+    const frontMatter = csv.frontmatter;
+    if(key in row) return row[key];
+    if(frontMatter && key in frontMatter) return frontMatter[key];
+    return '';
+  }
+
+  return body.replace(/\{\{(\w+)\}\}/g, (_, key) => `${replaceProp(key)}`);
+}