abi encode helpers

packages/ensjs/src/errors/utils.ts

@@ -162,3 +162,11 @@ export class InvalidContentHashError extends BaseError {
     super('Invalid content hash')
   }
 }
+
+export class UnknownContentTypeError extends BaseError {
+  override name = 'UnknownContentTypeError'
+
+  constructor({ contentType }: { contentType: string }) {
+    super(`Unknown content type: ${contentType}`)
+  }
+}

packages/ensjs/src/utils/encoders/encodeAbi.test.ts

@@ -1,4 +1,8 @@
-import { encodeAbi } from './encodeAbi.js'
+import {
+  contentTypeToEncodeAs,
+  encodeAbi,
+  encodeAsToContentType,
+} from './encodeAbi.js'
 
 describe('encodeAbi', () => {
   it('encodes data as JSON', async () => {
@@ -31,3 +35,43 @@ describe('encodeAbi', () => {
     expect(result.encodedData).toEqual('0x666f6f3d626172')
   })
 })
+
+describe('encodeAsToContentType', () => {
+  it('returns the correct content type for json', () => {
+    expect(encodeAsToContentType('json')).toEqual(1)
+  })
+  it('returns the correct content type for zlib', () => {
+    expect(encodeAsToContentType('zlib')).toEqual(2)
+  })
+  it('returns the correct content type for cbor', () => {
+    expect(encodeAsToContentType('cbor')).toEqual(4)
+  })
+  it('returns the correct content type for uri', () => {
+    expect(encodeAsToContentType('uri')).toEqual(8)
+  })
+  it('throws an error for an unknown content type', () => {
+    expect(() => encodeAsToContentType('foo' as any)).toThrow(
+      'Unknown content type: foo',
+    )
+  })
+})
+
+describe('contentTypeToEncodeAs', () => {
+  it('returns the correct encodeAs for json', () => {
+    expect(contentTypeToEncodeAs(1)).toEqual('json')
+  })
+  it('returns the correct encodeAs for zlib', () => {
+    expect(contentTypeToEncodeAs(2)).toEqual('zlib')
+  })
+  it('returns the correct encodeAs for cbor', () => {
+    expect(contentTypeToEncodeAs(4)).toEqual('cbor')
+  })
+  it('returns the correct encodeAs for uri', () => {
+    expect(contentTypeToEncodeAs(8)).toEqual('uri')
+  })
+  it('throws an error for an unknown content type', () => {
+    expect(() => contentTypeToEncodeAs(3 as any)).toThrow(
+      'Unknown content type: 3',
+    )
+  })
+})

packages/ensjs/src/utils/encoders/encodeAbi.ts

@@ -1,16 +1,18 @@
 import { bytesToHex, stringToHex, type Hex } from 'viem'
+import { UnknownContentTypeError } from '../../errors/utils.js'
 import type { Prettify } from '../../types.js'
 
 type AbiEncodeAs = 'json' | 'zlib' | 'cbor' | 'uri'
 
 type AbiContentType = 1 | 2 | 4 | 8
 
-type AbiEncodeMap = {
-  json: 1
-  zlib: 2
-  cbor: 4
-  uri: 8
-}
+const abiEncodeMap = {
+  json: 1,
+  zlib: 2,
+  cbor: 4,
+  uri: 8,
+} as const
+type AbiEncodeMap = typeof abiEncodeMap
 
 type GetAbiContentType<TEncodeAs extends AbiEncodeAs> = AbiEncodeMap[TEncodeAs]
 
@@ -33,6 +35,33 @@ export type EncodedAbi<TContentType extends AbiContentType = AbiContentType> = {
 export type EncodeAbiReturnType<TContentType extends AbiContentType> =
   EncodedAbi<TContentType>
 
+export const contentTypeToEncodeAs = (
+  contentType: AbiContentType,
+): AbiEncodeAs => {
+  switch (contentType) {
+    case 1:
+      return 'json'
+    case 2:
+      return 'zlib'
+    case 4:
+      return 'cbor'
+    case 8:
+      return 'uri'
+    default:
+      throw new UnknownContentTypeError({ contentType })
+  }
+}
+
+export const encodeAsToContentType = (
+  encodeAs: AbiEncodeAs,
+): AbiContentType => {
+  const contentType = abiEncodeMap[encodeAs]
+  if (contentType === undefined) {
+    throw new UnknownContentTypeError({ contentType: encodeAs })
+  }
+  return contentType
+}
+
 export const encodeAbi = async <
   TEncodeAs extends AbiEncodeAs,
   TContentType extends GetAbiContentType<TEncodeAs>,

packages/ensjs/src/utils/index.ts

@@ -1,5 +1,7 @@
 export {
+  contentTypeToEncodeAs,
   encodeAbi,
+  encodeAsToContentType,
   type EncodeAbiParameters,
   type EncodeAbiReturnType,
   type EncodedAbi,