import {
  cacheDirectory,
  copyAsync,
  deleteAsync,
  downloadAsync,
  FileSystemSessionType,
  FileSystemUploadType,
  getInfoAsync,
  uploadAsync,
} from "expo-file-system";
import {
  AbstractAccessor,
  DIR_SEPARATOR,
  FileSystemObject,
  LAST_DIR_SEPARATORS,
  Transferer,
} from "kura";

interface ExpoFsTransfererOptions {
  background?: boolean;
  getOnly?: boolean;
  threshold?: number;
}
export class ExpoFsTransferer extends Transferer {
  public constructor(private options?: ExpoFsTransfererOptions) {
    super();
    if (!options) {
      options = {};
    }
    if (options.getOnly == null) {
      options.getOnly = false;
    }
    if (options.background == null) {
      options.background = false;
    }
  }

  public async transfer(
    fromAccessor: AbstractAccessor,
    fromObj: FileSystemObject,
    toAccessor: AbstractAccessor,
    toObj: FileSystemObject
  ) {
    if (
      this.options.threshold != null &&
      fromObj.size < this.options.threshold
    ) {
      await super.transfer(fromAccessor, fromObj, toAccessor, toObj);
      return;
    }

    const fromUrl = await fromAccessor.getURL(fromObj.fullPath, "GET");
    const toUrl = await toAccessor.getURL(toObj.fullPath, "PUT");
    if (
      !fromUrl ||
      !toUrl ||
      (this.options.getOnly && !toUrl.startsWith("file:"))
    ) {
      await super.transfer(fromAccessor, fromObj, toAccessor, toObj);
      return;
    }

    if (fromUrl.startsWith("file:")) {
      if (toUrl.startsWith("file:")) {
        await copyAsync({ from: fromUrl, to: toUrl });
      } else {
        const uRes = await uploadAsync(toUrl, fromUrl, {
          httpMethod: "PUT",
          headers: {
            "Content-Length": fromObj.size + "",
          },
          sessionType: this.options.background
            ? FileSystemSessionType.BACKGROUND
            : FileSystemSessionType.FOREGROUND,
          uploadType: FileSystemUploadType.BINARY_CONTENT,
        });
        if (!(uRes.status + "").startsWith("2")) {
          throw uRes;
        }
      }
    } else {
      if (toUrl.startsWith("file:")) {
        const result = await downloadAsync(fromUrl, toUrl, {
          sessionType: this.options.background
            ? FileSystemSessionType.BACKGROUND
            : FileSystemSessionType.FOREGROUND,
        });
        if (!(result.status + "").startsWith("2")) {
          throw result;
        }
      } else {
        const tempUri =
          cacheDirectory.replace(LAST_DIR_SEPARATORS, "") +
          DIR_SEPARATOR +
          Date.now();
        try {
          const dRes = await downloadAsync(fromUrl, tempUri, {
            sessionType: this.options.background
              ? FileSystemSessionType.BACKGROUND
              : FileSystemSessionType.FOREGROUND,
          });
          if (!(dRes.status + "").startsWith("2")) {
            throw dRes;
          }
          const info = await getInfoAsync(tempUri);
          const uRes = await uploadAsync(toUrl, tempUri, {
            httpMethod: "PUT",
            headers: {
              "Content-Length": info.size + "",
            },
            sessionType: this.options.background
              ? FileSystemSessionType.BACKGROUND
              : FileSystemSessionType.FOREGROUND,
            uploadType: FileSystemUploadType.BINARY_CONTENT,
          });
          if (!(uRes.status + "").startsWith("2")) {
            throw uRes;
          }
        } finally {
          try {
            deleteAsync(tempUri);
          } catch {}
        }
      }
    }
  }
}