deerflow-code/frontend-web/src/core/api/markdown-docx-export.ts

import { apiFetch } from "@/core/api/fetch-client";
import { getBackendBaseURL } from "@/core/config";
import { OptType, writeYLog } from "@/core/log/y-log";
import { downloadMarkdownAsDocx } from "@/core/scheduled-tasks/markdown-docx";

function filenameFromContentDisposition(header: string | null): string | null {
  if (!header) return null;
  const star = /filename\*=(?:UTF-8'')?([^;]+)/i.exec(header);
  if (star) {
    const raw = star[1].replace(/["']/g, "").trim();
    try {
      return decodeURIComponent(raw);
    } catch {
      return raw;
    }
  }
  const plain = /filename="?([^";\n]+)"?/i.exec(header);
  return plain ? plain[1].trim() : null;
}

function sanitizeFallbackFilename(title: string | undefined): string {
  const base = (title?.trim() || "document").replace(/[<>:"/\\|?*\x00-\x1f]+/g, "_");
  return base.toLowerCase().endsWith(".docx") ? base : `${base}.docx`;
}

async function downloadBlobResponse(response: Response, fallbackFilename: string) {
  if (!response.ok) {
    const error = await response
      .json()
      .catch(() => ({ detail: "导出 Word 失败" }));
    const detail = error.detail;
    if (typeof detail === "string") throw new Error(detail);
    throw new Error("导出 Word 失败");
  }

  const blob = await response.blob();
  const filename =
    filenameFromContentDisposition(response.headers.get("Content-Disposition")) ??
    fallbackFilename;
  const url = URL.createObjectURL(blob);
  const anchor = document.createElement("a");
  anchor.href = url;
  anchor.download = filename;
  anchor.rel = "noopener";
  document.body.appendChild(anchor);
  anchor.click();
  anchor.remove();
  window.setTimeout(() => URL.revokeObjectURL(url), 30_000);
}

/**
 * 通用 Markdown → Word 导出（Gateway `writing` 路由，与 `/api/writing/rewrite` 同级）。
 *
 *   POST /api/writing/export/docx
 *   Body: { title?: string, markdown: string }
 *
 * 返回 `application/vnd.openxmlformats-officedocument.wordprocessingml.document`，
 * 文件名在 `Content-Disposition` 中。
 */
export async function downloadMarkdownDocxFromBackend(options: {
  title?: string;
  markdown: string;
}): Promise<void> {
  const markdown = options.markdown.trim();
  if (!markdown) {
    throw new Error("文档内容为空");
  }

  const fallbackFilename = sanitizeFallbackFilename(options.title);

  try {
    const response = await apiFetch(`${getBackendBaseURL()}/api/writing/export/docx`, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({
        title: options.title?.trim() || undefined,
        markdown,
      }),
    });

    if (response.status === 404) {
      await downloadMarkdownAsDocx(markdown, options.title?.trim() || "document", options.title);
      writeYLog({
        optType: OptType.export,
        optDetail: "CM助手-全量-导出-Word",
        url: `${getBackendBaseURL()}/api/writing/export/docx`,
        reqParam: { title: options.title?.trim() || undefined },
      });
      return;
    }

    await downloadBlobResponse(response, fallbackFilename);
    writeYLog({
      optType: OptType.export,
      optDetail: "CM助手-全量-导出-Word",
      url: `${getBackendBaseURL()}/api/writing/export/docx`,
      reqParam: { title: options.title?.trim() || undefined },
    });
  } catch (err) {
    if (err instanceof TypeError) {
      await downloadMarkdownAsDocx(markdown, options.title?.trim() || "document", options.title);
      writeYLog({
        optType: OptType.export,
        optDetail: "CM助手-全量-导出-Word",
        url: `${getBackendBaseURL()}/api/writing/export/docx`,
        reqParam: { title: options.title?.trim() || undefined },
      });
      return;
    }
    throw err;
  }
}