import * as commonUrl from "../common/url";
import * as d from "../localData";
import { ApiCodecType, GetCodecType, apiCodec } from "../common/apiCodec";

/**
 * definyのApi. api[api名](リクエストのデータ) で呼べる. 戻り値の Nothing は fetch が失敗した場合に返す.
 * いずれは, Result型を返したい
 */
export const api = Object.fromEntries(
  Object.entries(apiCodec).map(([apiName, codec]) => [
    apiName,
    (
      requestData: GetCodecType<ApiCodecType[keyof ApiCodecType]["request"]>
    ): Promise<
      d.Maybe<GetCodecType<ApiCodecType[keyof ApiCodecType]["response"]>>
    > => {
      console.log(apiName, "request", requestData);
      return fetch(commonUrl.apiUrl(apiName).toString(), {
        method: "POST",
        body: new Uint8Array(codec.request.encode(requestData as never)),
        headers: [["content-type", "application/octet-stream"]],
      })
        .then((response) => response.arrayBuffer())
        .then((binaryResponse) => {
          const response = codec.response.decode(
            0,
            new Uint8Array(binaryResponse)
          ).result;
          console.log(apiName, "response", response);
          return d.Maybe.Just(response);
        })
        .catch((reason) => {
          console.error(
            "definy api の " + apiName + " を呼ぶときにエラーが発生した",
            reason
          );
          return d.Maybe.Nothing();
        });
    },
  ])
) as {
  [apiName in keyof ApiCodecType]: (
    requestData: GetCodecType<ApiCodecType[apiName]["request"]>
  ) => Promise<d.Maybe<GetCodecType<ApiCodecType[apiName]["response"]>>>;
};

export const getImageWithCache = (
  imageHash: d.ImageHash
): Promise<d.Maybe<Uint8Array>> =>
  fetch(commonUrl.pngFileUrl(imageHash).toString(), { cache: "force-cache" })
    .then((response) => response.arrayBuffer())
    .then((response) => d.Maybe.Just(new Uint8Array(response)))
    .catch((reason) => {
      console.error(
        "imageToken = " + imageHash + " 画像の取得時にエラーが発生した",
        reason
      );
      return d.Maybe.Nothing();
    });