import { assertEquals } from "https://deno.land/std/testing/asserts.ts";

import {
  DenoKVBlobService,
  DenoKVFileService,
  FileMetaData,
  FileService,
} from "../src/fileservice.ts";

function generateLargeText(seed: number, size: number): string {
  const words = [
    "Norway",
    "Germany",
    "Ecuador",
    "Chile",
    "Colombia",
    "Sri Lanka",
    "Guinea",
    "United Kingdom",
    "Egypt",
    "Palau",
    "Latvia",
    "Congo, Democratic Republic of the",
    "Malawi",
    "Senegal",
    "Trinidad and Tobago",
    "Guatemala",
    "Chad",
    "New Zealand",
    "Malaysia",
    "Lithuania",
    "Taiwan",
    "Solomon Islands",
    "Grenada",
    "Hungary",
    "Korea, South",
  ];
  let ret: string[] = [];
  for (let i = 0; i < size; i++) {
    seed = (seed * 4931 + 2753) % words.length;
    ret.push(words[seed]);
  }
  return ret.join(" ");
}

async function asyncIterableToArray<T>(ite: AsyncIterable<T>): Promise<T[]> {
  const ret: T[] = [];
  for await (const e of ite) {
    ret.push(e);
  }
  return ret;
}

Deno.test("DenoKVBlobService happy path", async (t) => {
  localStorage.clear();
  const kv = await Deno.openKv(":memory:");

  const bs = new DenoKVBlobService(kv, 50);

  function toUint8Array(s: string): Uint8Array {
    return new TextEncoder().encode(s);
  }

  await t.step("read write small text", async () => {
    await bs.persistBlob("0002", toUint8Array("hello world"));
    const body = await bs.getBlob("0002");
    assertEquals(body, toUint8Array("hello world"));
    assertEquals(await bs.getNumberOfBlobs("0002"), 1);
  });

  await t.step("read write large text", async () => {
    const largeText = toUint8Array(generateLargeText(33, 100));
    await bs.persistBlob("0001", largeText);
    const body = await bs.getBlob("0001");
    assertEquals(body, largeText);
    assertEquals(await bs.getNumberOfBlobs("0001"), 21);
  });

  kv.close();
});

Deno.test("DenoKVFileService happy path", async (t) => {
  const kv = await Deno.openKv(":memory:");
  const fs: FileService = new DenoKVFileService(kv);
  const fileName1 = "didier/file1.txt";
  const fileName2 = "didier/file2.txt";
  let file1: FileMetaData | undefined;
  let file2: FileMetaData | undefined;

  await t.step("Create 2 files", async () => {
    file1 = await fs.createFromFullBody(fileName1, "bob le chef");
    file2 = await fs.createFromFullBody(fileName2, "le geant vert ☀️");

    assertEquals(file1.path, fileName1);
    assertEquals(file2.bodySize, "le geant vert ".length + 2);
  });

  await t.step("Get file metadata", async () => {
    const ret = await fs.getMetaDataByID(file1?.id ?? "404");
    assertEquals(ret, file1);
  });

  await t.step("List files", async () => {
    const expected = [file1, file2];
    const ret = await fs.list();
    assertEquals(await asyncIterableToArray(ret), expected);
  });

  await t.step("Get File by path", async () => {
    assertEquals(await fs.getFullBodyByPath(fileName1), "bob le chef");
  });

  await t.step("Get File by Id", async () => {
    assertEquals(await fs.getFullBodyByPath(fileName1), "bob le chef");
  });

  await t.step("Delete File", async () => {
    await fs.deleteByPath(fileName1);
    await fs.deleteByPath("404 not found");
  });

  await t.step("List after delete", async () => {
    const expected = [file2];
    const ret = await fs.list();
    assertEquals(await asyncIterableToArray(ret), expected);
  });

  await t.step("Rename file", async () => {
    const newPath = "boris/file2.txt";
    const ret = await fs.renameById(file2?.id ?? "404", newPath);
    assertEquals(ret?.path, newPath);

    assertEquals(
      (await fs.getFullBodyByPath(newPath))?.length,
      file2?.bodySize ?? -1,
    );
  });

  kv.close();
});

Deno.test("DenoKVFileService happy path with byte array", async (t) => {
  const kv = await Deno.openKv(":memory:");
  const fs: FileService = new DenoKVFileService(kv);
  await t.step("Create and read 1 binary file", async () => {
    const inputBody = new Uint8Array([240]);
    const file = await fs.createFromFullBody("hello", inputBody);

    assertEquals(file.path, "hello");
    assertEquals(file.bodySize, inputBody.length);

    const bodyString = await fs.getFullBodyByPath("hello");
    assertEquals(bodyString, new TextDecoder().decode(inputBody));
  });

  kv.close();
});