import { fetchPopiserverGateway as fetch } from "@/app/api/_popiserverFetch";
import { NextRequest } from "next/server";
import { ApiError } from "./_errors";
import { getPopiartApiBaseUrl } from "./_popiartBaseUrl";

const POPI_MEDIA_UPLOAD_PATH = "/api_client/media/upload";

type PopiserverResponse<T> = {
  status?: string;
  message?: string;
  data?: T;
};

type PopiMedia = {
  path?: string;
  url?: string;
  originPath?: string;
  originUrl?: string;
};

function getPopiBaseUrl(request: NextRequest): string {
  void request;
  return getPopiartApiBaseUrl();
}

function parseDataUrl(value: string): { mimeType: string; data: Buffer } | null {
  const match = value.match(/^data:([^;,]+)?(?:;[^,]*)?;base64,(.*)$/);
  if (!match) return null;
  return {
    mimeType: match[1] || "application/octet-stream",
    data: Buffer.from(match[2], "base64"),
  };
}

function extensionForMimeType(mimeType: string): string {
  const normalized = mimeType.toLowerCase();
  if (normalized === "image/jpeg") return "jpg";
  if (normalized === "image/png") return "png";
  if (normalized === "image/webp") return "webp";
  if (normalized === "image/gif") return "gif";
  if (normalized === "video/mp4") return "mp4";
  if (normalized === "video/webm") return "webm";
  if (normalized === "video/quicktime") return "mov";
  if (normalized === "audio/mpeg" || normalized === "audio/mp3") return "mp3";
  if (normalized === "audio/wav" || normalized === "audio/x-wav") return "wav";
  if (normalized === "audio/ogg") return "ogg";
  if (normalized === "audio/flac") return "flac";
  if (normalized === "audio/aac") return "aac";
  if (normalized === "model/gltf-binary") return "glb";
  return normalized.split("/")[1]?.replace(/[^a-z0-9]/g, "") || "bin";
}

function mediaResourceUrl(media: PopiMedia): string | null {
  return media.url || media.originUrl || media.path || media.originPath || null;
}

export function isDataUrl(value: string | null | undefined): value is string {
  return typeof value === "string" && value.startsWith("data:");
}

export async function uploadDataUrlToPopiMedia(
  request: NextRequest,
  token: string,
  dataUrl: string,
  filePrefix: string
): Promise<string> {
  const parsed = parseDataUrl(dataUrl);
  if (!parsed) {
    throw ApiError.badRequest("Invalid media data URL.");
  }

  const extension = extensionForMimeType(parsed.mimeType);
  const arrayBuffer = parsed.data.buffer.slice(
    parsed.data.byteOffset,
    parsed.data.byteOffset + parsed.data.byteLength
  ) as ArrayBuffer;
  const blob = new Blob([arrayBuffer], { type: parsed.mimeType });
  const formData = new FormData();
  formData.append("file", blob, `${filePrefix}-${Date.now()}.${extension}`);

  const upstream = await fetch(getPopiBaseUrl(request) + POPI_MEDIA_UPLOAD_PATH, {
    method: "POST",
    headers: {
      Accept: "application/json",
      Authorization: `Bearer ${token}`,
      token,
    },
    body: formData,
    cache: "no-store",
  });

  const payload = (await upstream.json().catch(() => null)) as PopiserverResponse<PopiMedia> | null;
  if (!upstream.ok) {
    throw ApiError.provider(payload?.message || "Popiserver media upload failed.", upstream.status);
  }
  if (!payload || payload.status !== "0000" || !payload.data) {
    throw ApiError.provider(payload?.message || "Popiserver media upload returned an error.", 502);
  }

  const url = mediaResourceUrl(payload.data);
  if (!url) {
    throw ApiError.provider("Popiserver media upload response is missing resource URL.", 502);
  }
  return url;
}