/* globals describe, it */

import { assert } from 'aegir/chai'
import OLDCID from 'cids'
import { base32 } from '../src/bases/base32.ts'
import { base36 } from '../src/bases/base36.ts'
import { base58btc } from '../src/bases/base58.ts'
import { base64 } from '../src/bases/base64.ts'
import { fromHex, toHex, equals } from '../src/bytes.ts'
import { sha256, sha512 } from '../src/hashes/sha2.ts'
import { varint, CID } from '../src/index.ts'
import invalidMultihash from './fixtures/invalid-multihash.ts'
import type { MultihashDigest } from '../src/index.ts'

const textEncoder = new TextEncoder()

describe('CID', () => {
  describe('v0', () => {
    it('handles B58Str multihash', () => {
      const mhStr = 'QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n'
      const cid = CID.parse(mhStr)

      assert.deepStrictEqual(cid.version, 0)
      assert.deepStrictEqual(cid.code, 112)
      assert.deepStrictEqual(cid.multihash.bytes, base58btc.baseDecode(mhStr))

      assert.deepStrictEqual(cid.toString(), mhStr)
    })

    it('create by parts', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(0, 112, hash)

      assert.deepStrictEqual(cid.code, 112)
      assert.deepStrictEqual(cid.version, 0)
      assert.deepStrictEqual(cid.multihash, hash)
      assert.deepStrictEqual(cid.toString(), base58btc.baseEncode(hash.bytes))
    })

    it('CID.createV0', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.createV0(hash)

      assert.deepStrictEqual(cid.code, 112)
      assert.deepStrictEqual(cid.version, 0)
      assert.deepStrictEqual(cid.multihash, hash)
      assert.deepStrictEqual(cid.toString(), base58btc.baseEncode(hash.bytes))
    })

    it('create from multihash', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))

      const cid = CID.decode(hash.bytes)

      assert.deepStrictEqual(cid.code, 112)
      assert.deepStrictEqual(cid.version, 0)
      assert.deepStrictEqual(cid.multihash.digest, hash.digest)
      assert.deepStrictEqual(
        { ...cid.multihash, digest: null },
        { ...hash, digest: null }
      )
      cid.toString()
      assert.deepStrictEqual(cid.toString(), base58btc.baseEncode(hash.bytes))
    })

    it('throws on invalid BS58Str multihash ', async () => {
      const msg = 'Non-base58btc character'
      assert.throws(
        () => CID.parse('QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zIII'),
        msg
      )
    })

    it('throws on trying to create a CIDv0 with a codec other than dag-pb', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const msg = 'Version 0 CID must use dag-pb (code: 112) block encoding'
      assert.throws(() => CID.create(0, 113, hash), msg)
    })

    it('throws on trying to base encode CIDv0 in other base than base58btc', async () => {
      const mhStr = 'QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n'
      const cid = CID.parse(mhStr)
      const msg = 'Cannot string encode V0 in base32 encoding'
      assert.throws(() => cid.toString(base32), msg)
    })

    it('throws on CIDv0 string with explicit multibase prefix', async () => {
      const str = 'zQmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n'
      const msg = 'Version 0 CID string must not include multibase prefix'
      assert.throws(() => CID.parse(str), msg)
    })

    it('.bytes', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const codec = 112
      const cid = CID.create(0, codec, hash)
      const bytes = cid.bytes
      assert.ok(bytes)
      const str = toHex(bytes)
      assert.deepStrictEqual(
        str,
        '1220ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad'
      )
    })

    it('should construct from an old CID', () => {
      const cidStr = 'QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n'
      const oldCid = CID.parse(cidStr)
      const newCid = CID.asCID(oldCid)
      assert.deepStrictEqual(newCid?.toString(), cidStr)
    })

    it('inspect bytes', () => {
      const byts = fromHex(
        '1220ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad'
      )
      const inspected = CID.inspectBytes(byts.subarray(0, 10)) // should only need the first few bytes
      assert.deepStrictEqual(
        {
          version: 0,
          codec: 0x70,
          multihashCode: 0x12,
          multihashSize: 34,
          digestSize: 32,
          size: 34
        },
        inspected
      )
    })

    describe('decodeFirst', () => {
      it('no remainder', () => {
        const byts = fromHex(
          '1220ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad'
        )
        const [cid, remainder] = CID.decodeFirst(byts)
        assert.deepStrictEqual(
          cid.toString(),
          'QmatYkNGZnELf8cAGdyJpUca2PyY4szai3RHyyWofNY1pY'
        )
        assert.deepStrictEqual(remainder.byteLength, 0)
      })

      it('remainder', () => {
        const byts = fromHex(
          '1220ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad0102030405'
        )
        const [cid, remainder] = CID.decodeFirst(byts)
        assert.deepStrictEqual(
          cid.toString(),
          'QmatYkNGZnELf8cAGdyJpUca2PyY4szai3RHyyWofNY1pY'
        )
        assert.deepStrictEqual(toHex(remainder), '0102030405')
      })
    })
  })

  describe('v1', () => {
    it('handles CID String (multibase encoded)', () => {
      const cidStr = 'zdj7Wd8AMwqnhJGQCbFxBVodGSBG84TM7Hs1rcJuQMwTyfEDS'
      const cid = CID.parse(cidStr)
      assert.deepStrictEqual(cid.code, 112)
      assert.deepStrictEqual(cid.version, 1)
      assert.ok(cid.multihash)
      assert.deepStrictEqual(cid.toString(), base32.encode(cid.bytes))
    })

    it('handles CID (no multibase)', () => {
      const cidStr =
        'bafybeidskjjd4zmr7oh6ku6wp72vvbxyibcli2r6if3ocdcy7jjjusvl2u'
      const cidBuf = fromHex(
        '017012207252523e6591fb8fe553d67ff55a86f84044b46a3e4176e10c58fa529a4aabd5'
      )
      const cid = CID.decode(cidBuf)
      assert.deepStrictEqual(cid.code, 112)
      assert.deepStrictEqual(cid.version, 1)
      assert.deepStrictEqual(cid.toString(), cidStr)
    })

    it('rejects a non-minimally encoded varint prefix', () => {
      // the version varint 0x01 replaced by its non-minimal encoding 0x81 0x00
      const cidBuf = fromHex(
        '81007012207252523e6591fb8fe553d67ff55a86f84044b46a3e4176e10c58fa529a4aabd5'
      )
      assert.throws(() => CID.decode(cidBuf), /minimal/)
    })

    it('create by parts', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(1, 0x71, hash)
      assert.deepStrictEqual(cid.code, 0x71)
      assert.deepStrictEqual(cid.version, 1)
      equalDigest(cid.multihash, hash)
    })

    it('CID.createV1', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.createV1(0x71, hash)

      assert.deepStrictEqual(cid.code, 0x71)
      assert.deepStrictEqual(cid.version, 1)
      equalDigest(cid.multihash, hash)
    })

    it('can roundtrip through cid.toString()', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid1 = CID.create(1, 0x71, hash)
      const cid2 = CID.parse(cid1.toString())

      assert.deepStrictEqual(cid1.code, cid2.code)
      assert.deepStrictEqual(cid1.version, cid2.version)
      assert.deepStrictEqual(cid1.multihash.digest, cid2.multihash.digest)
      assert.deepStrictEqual(cid1.multihash.bytes, cid2.multihash.bytes)
      const clear = { digest: null, bytes: null }
      assert.deepStrictEqual(
        { ...cid1.multihash, ...clear },
        { ...cid2.multihash, ...clear }
      )
    })

    it('.bytes', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const code = 0x71
      const cid = CID.create(1, code, hash)
      const bytes = cid.bytes
      assert.ok(bytes)
      const str = toHex(bytes)
      assert.deepStrictEqual(
        str,
        '01711220ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad'
      )
    })

    it('should construct from an old CID without a multibaseName', () => {
      const cidStr =
        'bafybeidskjjd4zmr7oh6ku6wp72vvbxyibcli2r6if3ocdcy7jjjusvl2u'
      const oldCid = CID.parse(cidStr)
      const newCid = CID.asCID(oldCid)
      assert.deepStrictEqual(newCid?.toString(), cidStr)
    })

    it('.link() should return this CID', () => {
      const cid = CID.parse('bafybeidskjjd4zmr7oh6ku6wp72vvbxyibcli2r6if3ocdcy7jjjusvl2u')
      assert.equal(cid, cid.link())
    })
  })

  describe('utilities', () => {
    const h1 = 'QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n'
    const h2 = 'QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1o'
    const h3 = 'zdj7Wd8AMwqnhJGQCbFxBVodGSBG84TM7Hs1rcJuQMwTyfEDS'

    it('.equals v0 to v0', () => {
      const cid1 = CID.parse(h1)
      assert.deepStrictEqual(cid1.equals(CID.parse(h1)), true)
      assert.deepStrictEqual(
        cid1.equals(CID.create(cid1.version, cid1.code, cid1.multihash)),
        true
      )

      const cid2 = CID.parse(h2)
      assert.deepStrictEqual(cid1.equals(CID.parse(h2)), false)
      assert.deepStrictEqual(
        cid1.equals(CID.create(cid2.version, cid2.code, cid2.multihash)),
        false
      )
    })

    it('.equals v0 to v1 and vice versa', () => {
      const cidV1 = CID.parse(h3)

      const cidV0 = cidV1.toV0()

      assert.deepStrictEqual(cidV0.equals(cidV1), false)
      assert.deepStrictEqual(cidV1.equals(cidV0), false)

      assert.deepStrictEqual(cidV1.multihash, cidV0.multihash)
    })

    it('.equals v1 to v1', () => {
      const cid1 = CID.parse(h3)

      assert.deepStrictEqual(cid1.equals(CID.parse(h3)), true)
      assert.deepStrictEqual(
        cid1.equals(CID.create(cid1.version, cid1.code, cid1.multihash)),
        true
      )
    })

    it('works with deepEquals', () => {
      const ch1 = CID.parse(h1)
      assert.deepStrictEqual(ch1, CID.parse(h1))
      assert.notDeepEqual(ch1, CID.parse(h2))
    })
  })

  describe('throws on invalid inputs', () => {
    const parse = [
      'hello world',
      'QmaozNR7DZHQK1ZcU9p7QdrshMvXqWK6gpu5rmrkPdT3L'
    ]

    for (const i of parse) {
      const name = `CID.parse(${JSON.stringify(i)})`
      it(name, async () => { assert.throws(() => CID.parse(i)) })
    }

    const decode = [
      textEncoder.encode('hello world'),
      textEncoder.encode('QmaozNR7DZHQK1ZcU9p7QdrshMvXqWK6gpu5rmrkPdT')
    ]

    for (const i of decode) {
      const name = `CID.decode(textEncoder.encode(${JSON.stringify(
        i.toString()
      )}))`
      it(name, async () => { assert.throws(() => CID.decode(i)) })
    }

    const create = [
      ...[...parse, ...decode].map((i) => [0, 112, i]),
      ...[...parse, ...decode].map((i) => [1, 112, i]),
      [18, 112, 'QmaozNR7DZHQK1ZcU9p7QdrshMvXqWK6gpu5rmrkPdT3L']
    ]

    for (const [version, code, hash] of create) {
      const form = JSON.stringify(hash.toString())
      const mh =
        hash instanceof Uint8Array ? `textEncoder.encode(${form})` : form
      const name = `CID.create(${version}, ${code}, ${mh})`
      // @ts-expect-error - version issn't always 0|1
      it(name, async () => { assert.throws(() => CID.create(version, code, hash)) })
    }

    it('invalid fixtures', async () => {
      for (const test of invalidMultihash) {
        const buff = fromHex(`0171${test.hex}`)
        assert.throws(() => CID.decode(buff), new RegExp(test.message))
      }
    })
  })

  describe('idempotence', () => {
    const h1 = 'QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n'
    const cid1 = CID.parse(h1)
    const cid2 = CID.asCID(cid1)

    it('constructor accept constructed instance', () => {
      assert.deepStrictEqual(cid1 === cid2, true)
    })
  })

  describe('conversion v0 <-> v1', () => {
    it('should convert v0 to v1', async () => {
      const hash = await sha256.digest(textEncoder.encode(`TEST${Date.now()}`))
      const cid = CID.create(0, 112, hash).toV1()
      assert.deepStrictEqual(cid.version, 1)
    })

    it('should convert v1 to v0', async () => {
      const hash = await sha256.digest(textEncoder.encode(`TEST${Date.now()}`))
      const cid = CID.create(1, 112, hash).toV0()
      assert.deepStrictEqual(cid.version, 0)
    })

    it('should not convert v1 to v0 if not dag-pb codec', async () => {
      const hash = await sha256.digest(textEncoder.encode(`TEST${Date.now()}`))
      const cid = CID.create(1, 0x71, hash)
      assert.throws(
        () => cid.toV0(),
        'Cannot convert a non dag-pb CID to CIDv0'
      )
    })

    it('should not convert v1 to v0 if not sha2-256 multihash', async () => {
      const hash = await sha512.digest(textEncoder.encode(`TEST${Date.now()}`))
      const cid = CID.create(1, 112, hash)
      assert.throws(
        () => cid.toV0(),
        'Cannot convert non sha2-256 multihash CID to CIDv0'
      )
    })

    it('should return assert.deepStrictEqual instance when converting v1 to v1', async () => {
      const hash = await sha512.digest(textEncoder.encode(`TEST${Date.now()}`))
      const cid = CID.create(1, 112, hash)

      assert.deepStrictEqual(cid.toV1() === cid, true)
    })

    it('should return assert.deepStrictEqual instance when converting v0 to v0', async () => {
      const hash = await sha256.digest(textEncoder.encode(`TEST${Date.now()}`))
      const cid = CID.create(0, 112, hash)
      assert.deepStrictEqual(cid.toV0() === cid, true)
    })

    it('should fail to convert unknown version', async () => {
      const hash = await sha256.digest(textEncoder.encode(`TEST${Date.now()}`))
      const cid = CID.create(0, 112, hash)
      const cid1 = Object.assign(Object.create(Object.getPrototypeOf(cid)), {
        ...cid
      })
      const cid2 = Object.assign(Object.create(Object.getPrototypeOf(cid)), {
        ...cid,
        version: 3
      })

      assert.deepStrictEqual(cid1.toV0().version, 0)
      assert.deepStrictEqual(cid1.toV1().version, 1)
      assert.equal(cid2.version, 3)

      assert.throws(
        () => cid2.toV1(),
        /Can not convert CID version 3 to version 1/
      )
      assert.throws(
        () => cid2.toV0(),
        /Can not convert CID version 3 to version 0/
      )
    })
  })

  describe('caching', () => {
    it('should cache CID as buffer', async () => {
      const hash = await sha256.digest(textEncoder.encode(`TEST${Date.now()}`))
      const cid = CID.create(1, 112, hash)
      assert.ok(cid.bytes)
      assert.deepStrictEqual(cid.bytes, cid.bytes)
    })

    it('should cache string representation when it matches the multibaseName it was constructed with', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(1, 112, hash)

      const b32 = {
        ...base32,
        callCount: 0,
        encode (bytes: Uint8Array): string {
          this.callCount += 1
          return base32.encode(bytes) + '!'
        }
      }

      const b64 = {
        ...base64,
        callCount: 0,
        encode (bytes: Uint8Array): string {
          this.callCount += 1
          return base64.encode(bytes)
        }
      }

      const base32String =
        'bafybeif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu'
      assert.deepEqual(cid.toString(b32), `${base32String}!`)
      assert.deepEqual(b32.callCount, 1)
      assert.deepEqual(cid.toString(), `${base32String}!`)
      assert.deepEqual(b32.callCount, 1)

      assert.deepStrictEqual(
        cid.toString(b64),
        'mAXASILp4Fr+PAc/qQUFA3l2uIiOwA2Gjlhd6nLQQ/2HyABWt'
      )
      assert.equal(b64.callCount, 1)
      assert.deepStrictEqual(
        cid.toString(b64),
        'mAXASILp4Fr+PAc/qQUFA3l2uIiOwA2Gjlhd6nLQQ/2HyABWt'
      )
      assert.equal(b64.callCount, 1)
    })

    it('should cache string representation when constructed with one', () => {
      const base32String =
        'bafybeif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu'
      const cid = CID.parse(base32String)

      assert.deepStrictEqual(
        cid.toString({
          ...base32,
          encode () {
            throw Error('Should not call decode')
          }
        }),
        base32String
      )
    })
  })

  it('toJSON()', async () => {
    const hash = await sha256.digest(textEncoder.encode('abc'))
    const cid = CID.create(1, 112, hash)

    assert.deepStrictEqual(cid.toJSON(), {
      '/': cid.toString()
    })
  })

  it('asCID', async () => {
    const hash = await sha256.digest(textEncoder.encode('abc'))
    class IncompatibleCID {
      readonly version: number
      readonly code: number
      readonly multihash: MultihashDigest
      readonly asCID: this

      constructor (version: number, code: number, multihash: MultihashDigest) {
        this.version = version
        this.code = code
        this.multihash = multihash
        this.asCID = this
      }

      get [Symbol.for('@ipld/js-cid/CID')] (): boolean {
        return true
      }
    }

    const version = 1
    const code = 112

    const incompatibleCID = new IncompatibleCID(version, code, hash)

    assert.strictEqual(incompatibleCID.toString(), '[object Object]')
    // @ts-expect-error - no such method
    assert.strictEqual(typeof incompatibleCID.toV0, 'undefined')

    const cid1 = CID.asCID(incompatibleCID)
    assert.ok(cid1 instanceof CID)
    assert.strictEqual(cid1.code, code)
    assert.strictEqual(cid1.version, version)
    assert.ok(equals(cid1.multihash.bytes, hash.bytes))

    const cid2 = CID.asCID({ version, code, hash })
    assert.strictEqual(cid2, null)

    const duckCID = { version, code, multihash: hash }
    // @ts-expect-error - no such property
    duckCID.asCID = duckCID
    const cid3 = CID.asCID(duckCID) as CID
    assert.ok(cid3 instanceof CID)
    assert.strictEqual(cid3.code, code)
    assert.strictEqual(cid3.version, version)
    assert.ok(equals(cid3.multihash.bytes, hash.bytes))

    const cid4 = CID.asCID(cid3)
    assert.strictEqual(cid3, cid4)

    const cid5 = (
      CID.asCID(new OLDCID(1, 'raw', Uint8Array.from(hash.bytes)))
    )
    assert.ok(cid5 instanceof CID)
    assert.strictEqual(cid5.version, 1)
    assert.ok(equals(cid5.multihash.bytes, hash.bytes))
    assert.strictEqual(cid5.code, 85)
  })

  const digestsame = (x: CID, y: CID): void => {
    // @ts-expect-error not sure what this supposed to be
    assert.deepStrictEqual(x.hash, y.hash)
    assert.deepStrictEqual(x.bytes, y.bytes)
    if (x.multihash != null) {
      equalDigest(x.multihash, y.multihash)
    }
    const empty = { hash: null, bytes: null, digest: null, multihash: null }
    assert.deepStrictEqual({ ...x, ...empty }, { ...y, ...empty })
  }

  const equalDigest = (x?: MultihashDigest, y?: MultihashDigest): void => {
    assert.ok(x)
    assert.ok(y)
    assert.deepStrictEqual(x.digest, y.digest)
    assert.deepStrictEqual(x.code, y.code)
    assert.deepStrictEqual(x.digest, y.digest)
  }

  describe('CID.parse', async () => {
    it('parse 32 encoded CIDv1', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(1, 112, hash)

      const parsed = CID.parse(cid.toString(base32))
      digestsame(cid, parsed)
    })

    it('parse 36 encoded CIDv1', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(1, 112, hash)

      const parsed = CID.parse(cid.toString(base36))
      digestsame(cid, parsed)
    })

    it('parse base58btc encoded CIDv1', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(1, 112, hash)

      const parsed = CID.parse(cid.toString(base58btc))
      digestsame(cid, parsed)
    })

    it('parse base58btc encoded CIDv0', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(0, 112, hash)

      const parsed = CID.parse(cid.toString())
      digestsame(cid, parsed)
    })

    it('fails to parse base64 encoded CIDv1', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(1, 112, hash)
      const msg =
        'To parse non base32, base36 or base58btc encoded CID multibase decoder must be provided'

      assert.throws(() => CID.parse(cid.toString(base64)), msg)
    })

    it('parses base64 encoded CIDv1 if base64 is provided', async () => {
      const hash = await sha256.digest(textEncoder.encode('abc'))
      const cid = CID.create(1, 112, hash)

      const parsed = CID.parse(cid.toString(base64), base64)
      digestsame(cid, parsed)
    })
  })

  it('inspect bytes', () => {
    const byts = fromHex(
      '01711220ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad'
    )
    const inspected = CID.inspectBytes(byts.subarray(0, 10)) // should only need the first few bytes
    assert.deepStrictEqual(
      {
        version: 1,
        codec: 0x71,
        multihashCode: 0x12,
        multihashSize: 34,
        digestSize: 32,
        size: 36
      },
      inspected
    )

    describe('decodeFirst', () => {
      it('no remainder', () => {
        const byts = fromHex(
          '01711220ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad'
        )
        const [cid, remainder] = CID.decodeFirst(byts)
        assert.deepStrictEqual(
          cid.toString(),
          'bafyreif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu'
        )
        assert.deepStrictEqual(remainder.byteLength, 0)
      })

      it('remainder', () => {
        const byts = fromHex(
          '01711220ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad0102030405'
        )
        const [cid, remainder] = CID.decodeFirst(byts)
        assert.deepStrictEqual(
          cid.toString(),
          'bafyreif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu'
        )
        assert.deepStrictEqual(toHex(remainder), '0102030405')
      })
    })
  })

  it('new CID from old CID', async () => {
    const hash = await sha256.digest(textEncoder.encode('abc'))
    const cid = (
      CID.asCID(new OLDCID(1, 'raw', Uint8Array.from(hash.bytes)))
    )
    assert.deepStrictEqual(cid?.version, 1)

    equalDigest(cid?.multihash, hash)
    assert.deepStrictEqual(cid?.code, 85)
  })

  it('util.inspect', async () => {
    const hash = await sha256.digest(textEncoder.encode('abc'))
    const cid = CID.create(1, 112, hash)
    assert.deepStrictEqual(
      // @ts-expect-error - no such method is known
      typeof cid[Symbol.for('nodejs.util.inspect.custom')],
      'function'
    )
    assert.deepStrictEqual(
      // @ts-expect-error - no such method is known
      cid[Symbol.for('nodejs.util.inspect.custom')](),
      'CID(bafybeif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu)'
    )
  })

  it('invalid CID version', async () => {
    const encoded = varint.encodeTo(2, new Uint8Array(32))
    assert.throws(() => CID.decode(encoded), 'Invalid CID version 2')
  })

  it('CID can be moved across JS realms', async () => {
    const cid = CID.parse('bafybeif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu')
    const { port1: sender, port2: receiver } = new MessageChannel()
    sender.postMessage(cid)
    const cid2 = await new Promise<CID>((resolve) => {
      receiver.onmessage = (event) => { resolve(event.data) }
    })
    sender.close()
    receiver.close()
    assert.strictEqual(cid2['/'], cid2.bytes)
  })

  describe('decode', () => {
    const tests = {
      v0: 'QmTFHZL5CkgNz19MdPnSuyLAi6AVq9fFp81zmPpaL2amED',
      v1: 'bafybeif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu'
    }

    Object.entries(tests).forEach(([version, cidString]) => {
      it(`decode ${version} from bytes`, () => {
        const cid1 = CID.parse(cidString)
        const cid2 = CID.decode(cid1.bytes)

        assert.deepStrictEqual(cid1, cid2)
      })

      it(`decode ${version} from subarray`, () => {
        const cid1 = CID.parse(cidString)
        // a byte array with an extra byte at the start and end
        const bytes = new Uint8Array(cid1.bytes.length + 2)
        bytes.set(cid1.bytes, 1)
        // slice the cid bytes out of the middle to have a subarray with a non-zero .byteOffset
        const subarray = bytes.subarray(1, cid1.bytes.length + 1)
        const cid2 = CID.decode(subarray)

        assert.deepStrictEqual(cid1, cid2)
        assert.equal(cid1.byteLength, cid2.byteLength)
        assert.equal(typeof cid2.byteOffset, 'number')
      })
    })
  })
})