feat: 建立 DOCX 共享协议与准备服务

packages/application/src/application-service.ts

@@ -2,6 +2,12 @@ import {
   MarkdownDocumentParseError,
   renderMarkdown
 } from "@md-to-pdf/renderer";
+import {
+  docxExportRequestSchema,
+  type DocxExportRequest,
+  type RenderedMarkdownDocument,
+  type ThemeManifest
+} from "@md-to-pdf/core";
 import {
   createThemeRegistry,
   type ThemeRegistryOptions
@@ -35,6 +41,16 @@ export interface ApplicationServiceOptions
   extends ThemeRegistryOptions,
     ImageResourceResolverOptions {}
 
+export interface PreparedDocxExport {
+  request: DocxExportRequest;
+  document: RenderedMarkdownDocument;
+  theme: {
+    manifest: ThemeManifest;
+    source: "bundled" | "local";
+    css: string;
+  };
+}
+
 export function createApplicationService(
   options: ApplicationServiceOptions
 ) {
@@ -113,11 +129,92 @@ export function createApplicationService(
     };
   }
 
+  async function prepareDocxExport(
+    request: unknown,
+    context: ImageResolutionContext = {}
+  ): Promise<PreparedDocxExport> {
+    const parsed = docxExportRequestSchema.safeParse(request);
+    if (!parsed.success) {
+      const firstField = parsed.error.issues[0]?.path[0];
+      if (firstField === "exportConfig") {
+        throw new ApplicationRequestError(
+          400,
+          "INVALID_EXPORT_CONFIG",
+          "导出配置无效"
+        );
+      }
+      if (firstField === "fileName") {
+        throw new ApplicationRequestError(
+          400,
+          "INVALID_FILE_NAME",
+          "fileName 必须是长度不超过 500 的字符串"
+        );
+      }
+      if (firstField === "markdown") {
+        const markdownTooLarge = parsed.error.issues.some(
+          (issue) =>
+            issue.path[0] === "markdown" && issue.code === "too_big"
+        );
+        throw new ApplicationRequestError(
+          markdownTooLarge ? 413 : 400,
+          markdownTooLarge ? "MARKDOWN_TOO_LARGE" : "INVALID_MARKDOWN",
+          markdownTooLarge
+            ? "Markdown 内容不能超过 1.5 MB"
+            : "markdown 必须是字符串"
+        );
+      }
+      if (firstField === "resources") {
+        throw new ApplicationRequestError(
+          400,
+          "INVALID_IMAGE_RESOURCES",
+          "图片资源参数无效"
+        );
+      }
+      throw new ApplicationRequestError(
+        400,
+        "INVALID_DOCX_REQUEST",
+        "DOCX 导出请求无效"
+      );
+    }
+
+    const theme = await themes.get(parsed.data.exportConfig.themeId);
+    if (!theme) {
+      throw new ApplicationRequestError(
+        404,
+        "THEME_NOT_FOUND",
+        "未找到指定主题"
+      );
+    }
+
+    const [document, themeCss] = await Promise.all([
+      render(parsed.data, context),
+      themes.getCss(theme.manifest.id)
+    ]);
+    if (themeCss === undefined) {
+      throw new ApplicationRequestError(
+        404,
+        "THEME_NOT_FOUND",
+        "未找到指定主题"
+      );
+    }
+
+    return {
+      request: parsed.data,
+      document,
+      theme: {
+        manifest: theme.manifest,
+        source: theme.source,
+        css: themeCss
+      }
+    };
+  }
+
   return {
     getThemeAsset: themes.getAsset,
     getThemeCss: themes.getCss,
     invalidateThemes: themes.invalidate,
     listThemes,
+    prepareDocxExport,
     render
   };
 }