import { configManager } from "@/lib/admin/config-manager";

export async function getCollaboraEditUrl(
  fileId: string,
  fileName: string
): Promise<string> {
  const serverUrl =
    configManager.get<string>("collaboraServerUrl") ||
    process.env.COLLABORA_SERVER_URL ||
    "";

  if (!serverUrl) {
    throw new Error("COLLABORA_SERVER_URL is not configured");
  }

  const base = serverUrl.replace(/\/+$/, "");
  const fileExt = fileName.split(".").pop()?.toLowerCase() || "";

  // Collabora WOPI host discovery endpoint
  const response = await fetch(`${base}/hosting/discovery`, {
    headers: { Accept: "application/json" },
  });

  if (!response.ok) {
    throw new Error(`Collabora discovery failed: ${response.status}`);
  }

  const discovery = await response.json();

  // Find the WOPI action URL for the file extension
  let actionUrl: string | null = null;
  const mimeMap: Record<string, string> = {
    docx: "text",
    doc: "text",
    odt: "text",
    xlsx: "spreadsheet",
    xls: "spreadsheet",
    ods: "spreadsheet",
    pptx: "presentation",
    ppt: "presentation",
    odp: "presentation",
  };
  const docType = mimeMap[fileExt] || "text";

  if (discovery.net?.zone) {
    const zones = Array.isArray(discovery.net.zone)
      ? discovery.net.zone
      : [discovery.net.zone];
    for (const zone of zones) {
      const apps = Array.isArray(zone.app) ? zone.app : zone.app ? [zone.app] : [];
      for (const app of apps) {
        if (
          app.name &&
          docType &&
          app.name.toLowerCase().includes(docType.toLowerCase())
        ) {
          const actions = Array.isArray(app.action)
            ? app.action
            : app.action
              ? [app.action]
              : [];
          for (const action of actions) {
            if (action.name === "edit" && action.urlsrc) {
              actionUrl = action.urlsrc;
              break;
            }
          }
        }
        if (actionUrl) break;
      }
      if (actionUrl) break;
    }
  }

  if (!actionUrl) {
    // Fallback: construct URL manually
    actionUrl = `${base}/loleaflet/dist/loleaflet.html`;
  }

  // For now, return the base edit URL. A full WOPI implementation would
  // generate a WOPI src URL with an access token pointing back to this server.
  const wopiSrcUrl = `${actionUrl}?WOPISrc=${encodeURIComponent(
    `${process.env.NEXT_PUBLIC_APP_URL || `http://localhost:${process.env.PORT || 3000}`}/api/collabora/wopi/files/${encodeURIComponent(fileId)}`
  )}`;

  return wopiSrcUrl;
}