// Copyright (c) 2018-present, Cruise LLC

// This source code is licensed under the Apache License, Version 2.0,
// found in the LICENSE file in the root directory of this source tree.
// You may not use this file except in compliance with the License.

// @flow

import { Reader, extractFields, extractTime } from ".";

describe("browser reader", () => {
  it("works in node", (done) => {
    const buffer = new Blob([Uint8Array.from([0x00, 0x01, 0x02, 0x03, 0x04])]);
    const reader = new Reader(buffer);
    reader.read(0, 2, (err: Error | null, res: any) => {
      expect(err).toBeNull();
      expect(res).toHaveLength(2);
      expect(res instanceof Buffer).toBe(true);
      expect(res[0]).toBe(0x00);
      expect(res[1]).toBe(0x01);
      done();
    });
  });

  it("allows multiple read operations at once", async () => {
    const buffer = new Blob([Uint8Array.from([0x00, 0x01, 0x02, 0x03, 0x04])]);
    const reader = new Reader(buffer);
    const read1 = new Promise((resolve, reject) => reader.read(0, 2, (err) => (err ? reject(err) : resolve())));
    const read2 = new Promise((resolve, reject) => reader.read(0, 2, (err) => (err ? reject(err) : resolve())));
    await Promise.all([read1, read2]);
  });

  it("reports browser FileReader errors", (done) => {
    const buffer = new Blob([Uint8Array.from([0x00, 0x01, 0x02, 0x03, 0x04])]);
    const reader = new Reader(buffer);
    const actualFileReader = global.FileReader;
    global.FileReader = class FailReader {
      onerror: any;
      readAsArrayBuffer() {
        setTimeout(() => {
          // $FlowFixMe - `value` is missing in object literal
          Object.defineProperty(this, "error", {
            get() {
              return "fake error";
            },
          });

          expect(typeof this.onerror).toBe("function");
          this.onerror(this);
        });
      }
    };

    reader.read(0, 2, (err: Error | null) => {
      global.FileReader = actualFileReader;
      expect(err instanceof Error).toBe(true);

      // $FlowFixMe - `message` is missing in null
      expect(err.message).toBe("fake error");
      done();
    });
  });

  it("exposes other methods", () => {
    expect(extractFields).toBeDefined();
    expect(extractTime).toBeDefined();
  });
});