feat(core): added plutus and native scripts serialization classes

packages/core/src/Cardano/types/Script.ts

@@ -233,3 +233,17 @@ export interface PlutusScript {
  * Program that decides whether the transaction that spends the output is authorized to do so.
  */
 export type Script = NativeScript | PlutusScript;
+
+/**
+ * Predicate that returns true if the given core script is a native script.
+ *
+ * @param script The Script to check.
+ */
+export const isNativeScript = (script: Script): script is NativeScript => script.__type === ScriptType.Native;
+
+/**
+ * Predicate that returns true if the given core script is a plutus script.
+ *
+ * @param script The Script to check.
+ */
+export const isPlutusScript = (script: Script): script is PlutusScript => script.__type === ScriptType.Plutus;

packages/core/src/Serialization/Scripts/NativeScript/NativeScript.ts

@@ -0,0 +1,337 @@
+import * as Cardano from '../../../Cardano';
+import * as Crypto from '@cardano-sdk/crypto';
+import { CborReader } from '../../CBOR';
+import { HexBlob, InvalidStateError } from '@cardano-sdk/util';
+import { ScriptAll } from './ScriptAll';
+import { ScriptAny } from './ScriptAny';
+import { ScriptNOfK } from './ScriptNOfK';
+import { ScriptPubkey } from './ScriptPubkey';
+import { TimelockExpiry } from './TimelockExpiry';
+import { TimelockStart } from './TimelockStart';
+
+const HASH_LENGTH_IN_BYTES = 28;
+
+/**
+ * The Native scripts form an expression tree, the evaluation of the script produces either true or false.
+ *
+ * Note that it is recursive. There are no constraints on the nesting or size, except that imposed by the overall
+ * transaction size limit (given that the script must be included in the transaction in a script witnesses).
+ */
+export class NativeScript {
+  #scriptAll: ScriptAll | undefined;
+  #scriptAny: ScriptAny | undefined;
+  #scripNOfK: ScriptNOfK | undefined;
+  #scriptPubKey: ScriptPubkey | undefined;
+  #timelockExpiry: TimelockExpiry | undefined;
+  #timelockStart: TimelockStart | undefined;
+  #kind: Cardano.NativeScriptKind;
+  #originalBytes: HexBlob | undefined = undefined;
+
+  /**
+   * Serializes a NativeScript into CBOR format.
+   *
+   * @returns The NativeScript in CBOR format.
+   */
+  toCbor(): HexBlob {
+    if (this.#originalBytes) return this.#originalBytes;
+
+    let cbor;
+
+    switch (this.#kind) {
+      case Cardano.NativeScriptKind.RequireSignature:
+        cbor = this.#scriptPubKey!.toCbor();
+        break;
+      case Cardano.NativeScriptKind.RequireAllOf:
+        cbor = this.#scriptAll!.toCbor();
+        break;
+      case Cardano.NativeScriptKind.RequireAnyOf:
+        cbor = this.#scriptAny!.toCbor();
+        break;
+      case Cardano.NativeScriptKind.RequireNOf:
+        cbor = this.#scripNOfK!.toCbor();
+        break;
+      case Cardano.NativeScriptKind.RequireTimeAfter:
+        cbor = this.#timelockStart!.toCbor();
+        break;
+      case Cardano.NativeScriptKind.RequireTimeBefore:
+        cbor = this.#timelockExpiry!.toCbor();
+        break;
+      default:
+        throw new InvalidStateError(`Unexpected kind value: ${this.#kind}`);
+    }
+
+    return cbor;
+  }
+
+  /**
+   * Deserializes the NativeScript from a CBOR byte array.
+   *
+   * @param cbor The CBOR encoded NativeScript object.
+   * @returns The new NativeScript instance.
+   */
+  static fromCbor(cbor: HexBlob): NativeScript {
+    let nativeScript: NativeScript;
+
+    const reader = new CborReader(cbor);
+
+    reader.readStartArray();
+    const kind = Number(reader.readInt());
+
+    switch (kind) {
+      case Cardano.NativeScriptKind.RequireSignature:
+        nativeScript = NativeScript.newScriptPubkey(ScriptPubkey.fromCbor(cbor));
+        break;
+      case Cardano.NativeScriptKind.RequireAllOf:
+        nativeScript = NativeScript.newScriptAll(ScriptAll.fromCbor(cbor));
+        break;
+      case Cardano.NativeScriptKind.RequireAnyOf:
+        nativeScript = NativeScript.newScriptAny(ScriptAny.fromCbor(cbor));
+        break;
+      case Cardano.NativeScriptKind.RequireNOf:
+        nativeScript = NativeScript.newScriptNOfK(ScriptNOfK.fromCbor(cbor));
+        break;
+      case Cardano.NativeScriptKind.RequireTimeAfter:
+        nativeScript = NativeScript.newTimelockStart(TimelockStart.fromCbor(cbor));
+        break;
+      case Cardano.NativeScriptKind.RequireTimeBefore:
+        nativeScript = NativeScript.newTimelockExpiry(TimelockExpiry.fromCbor(cbor));
+        break;
+      default:
+        throw new InvalidStateError(`Unexpected kind value: ${kind}`);
+    }
+
+    nativeScript.#originalBytes = cbor;
+
+    return nativeScript;
+  }
+
+  /**
+   * Creates a Core NativeScript object from the current NativeScript object.
+   *
+   * @returns The Core NativeScript object.
+   */
+  toCore(): Cardano.NativeScript {
+    let core;
+
+    switch (this.#kind) {
+      case Cardano.NativeScriptKind.RequireSignature:
+        core = this.#scriptPubKey!.toCore();
+        break;
+      case Cardano.NativeScriptKind.RequireAllOf:
+        core = this.#scriptAll!.toCore();
+        break;
+      case Cardano.NativeScriptKind.RequireAnyOf:
+        core = this.#scriptAny!.toCore();
+        break;
+      case Cardano.NativeScriptKind.RequireNOf:
+        core = this.#scripNOfK!.toCore();
+        break;
+      case Cardano.NativeScriptKind.RequireTimeAfter:
+        core = this.#timelockStart!.toCore();
+        break;
+      case Cardano.NativeScriptKind.RequireTimeBefore:
+        core = this.#timelockExpiry!.toCore();
+        break;
+      default:
+        throw new InvalidStateError(`Unexpected kind value: ${this.#kind}`);
+    }
+
+    return core;
+  }
+
+  /**
+   * Creates a NativeScript object from the given Core NativeScript object.
+   *
+   * @param script The core NativeScript object.
+   */
+  static fromCore(script: Cardano.NativeScript): NativeScript {
+    let nativeScript: NativeScript;
+
+    switch (script.kind) {
+      case Cardano.NativeScriptKind.RequireSignature:
+        nativeScript = NativeScript.newScriptPubkey(ScriptPubkey.fromCore(script));
+        break;
+      case Cardano.NativeScriptKind.RequireAllOf:
+        nativeScript = NativeScript.newScriptAll(ScriptAll.fromCore(script));
+        break;
+      case Cardano.NativeScriptKind.RequireAnyOf:
+        nativeScript = NativeScript.newScriptAny(ScriptAny.fromCore(script));
+        break;
+      case Cardano.NativeScriptKind.RequireNOf:
+        nativeScript = NativeScript.newScriptNOfK(ScriptNOfK.fromCore(script));
+        break;
+      case Cardano.NativeScriptKind.RequireTimeAfter:
+        nativeScript = NativeScript.newTimelockStart(TimelockStart.fromCore(script));
+        break;
+      case Cardano.NativeScriptKind.RequireTimeBefore:
+        nativeScript = NativeScript.newTimelockExpiry(TimelockExpiry.fromCore(script));
+        break;
+      default:
+        throw new InvalidStateError('Unexpected kind value'); // Shouldn't happen.
+    }
+
+    return nativeScript;
+  }
+
+  /**
+   * Computes the script hash of this native script.
+   *
+   * @returns the script hash.
+   */
+  hash(): Crypto.Hash28ByteBase16 {
+    // To compute a script hash, note that you must prepend a tag to the bytes of
+    // the script before hashing. The tags in the Babbage era for native scripts is "\x00"
+    const bytes = `00${this.toCbor()}`;
+
+    const hash = Crypto.blake2b(HASH_LENGTH_IN_BYTES).update(Buffer.from(bytes, 'hex')).digest();
+
+    return Crypto.Hash28ByteBase16(HexBlob.fromBytes(hash));
+  }
+
+  /**
+   * Gets the native script kind.
+   *
+   * @returns The native script kind.
+   */
+  kind(): Cardano.NativeScriptKind {
+    return this.#kind;
+  }
+
+  /**
+   * Gets a NativeScript from a ScriptPubkey instance.
+   *
+   * @param scriptPubkey The ScriptPubkey instance to 'cast' to native script.
+   */
+  static newScriptPubkey(scriptPubkey: ScriptPubkey): NativeScript {
+    const script = new NativeScript();
+
+    script.#scriptPubKey = scriptPubkey;
+    script.#kind = Cardano.NativeScriptKind.RequireSignature;
+
+    return script;
+  }
+
+  /**
+   * Gets a NativeScript from a ScriptAll instance.
+   *
+   * @param scriptAll The ScriptAll instance to 'cast' to native script.
+   */
+  static newScriptAll(scriptAll: ScriptAll): NativeScript {
+    const script = new NativeScript();
+
+    script.#scriptAll = scriptAll;
+    script.#kind = Cardano.NativeScriptKind.RequireAllOf;
+
+    return script;
+  }
+
+  /**
+   * Gets a NativeScript from a ScriptAny instance.
+   *
+   * @param scriptAny The ScriptAny instance to 'cast' to native script.
+   */
+  static newScriptAny(scriptAny: ScriptAny): NativeScript {
+    const script = new NativeScript();
+
+    script.#scriptAny = scriptAny;
+    script.#kind = Cardano.NativeScriptKind.RequireAnyOf;
+
+    return script;
+  }
+
+  /**
+   * Gets a NativeScript from a ScriptNOfK instance.
+   *
+   * @param scriptNOfK The ScriptNOfK instance to 'cast' to native script.
+   */
+  static newScriptNOfK(scriptNOfK: ScriptNOfK): NativeScript {
+    const script = new NativeScript();
+
+    script.#scripNOfK = scriptNOfK;
+    script.#kind = Cardano.NativeScriptKind.RequireNOf;
+
+    return script;
+  }
+
+  /**
+   * Gets a NativeScript from a TimelockStart instance.
+   *
+   * @param timelockStart The TimelockStart instance to 'cast' to native script.
+   */
+  static newTimelockStart(timelockStart: TimelockStart): NativeScript {
+    const script = new NativeScript();
+
+    script.#timelockStart = timelockStart;
+    script.#kind = Cardano.NativeScriptKind.RequireTimeAfter;
+
+    return script;
+  }
+
+  /**
+   * Gets a NativeScript from a TimelockExpiry instance.
+   *
+   * @param timelockExpiry The TimelockExpiry instance to 'cast' to native script.
+   */
+  static newTimelockExpiry(timelockExpiry: TimelockExpiry): NativeScript {
+    const script = new NativeScript();
+
+    script.#timelockExpiry = timelockExpiry;
+    script.#kind = Cardano.NativeScriptKind.RequireTimeBefore;
+
+    return script;
+  }
+
+  /**
+   * Gets a ScriptPubkey from a NativeScript instance.
+   *
+   * @returns a ScriptPubkey if the native script can be down cast, otherwise, undefined.
+   */
+  asScriptPubkey(): ScriptPubkey | undefined {
+    return this.#scriptPubKey;
+  }
+
+  /**
+   * Gets a ScriptAll from a NativeScript instance.
+   *
+   * @returns a ScriptAll if the native script can be down cast, otherwise, undefined.
+   */
+  asScriptAll(): ScriptAll | undefined {
+    return this.#scriptAll;
+  }
+
+  /**
+   * Gets a ScriptAny from a NativeScript instance.
+   *
+   * @returns a ScriptAny if the native script can be down cast, otherwise, undefined.
+   */
+  asScriptAny(): ScriptAny | undefined {
+    return this.#scriptAny;
+  }
+
+  /**
+   * Gets a ScriptNOfK from a NativeScript instance.
+   *
+   * @returns a ScriptNOfK if the native script can be down cast, otherwise, undefined.
+   */
+  asScriptNOfK(): ScriptNOfK | undefined {
+    return this.#scripNOfK;
+  }
+
+  /**
+   * Gets a TimelockStart from a NativeScript instance.
+   *
+   * @returns a TimelockStart if the native script can be down cast, otherwise, undefined.
+   */
+  asTimelockStart(): TimelockStart | undefined {
+    return this.#timelockStart;
+  }
+
+  /**
+   * Gets a TimelockExpiry from a NativeScript instance.
+   *
+   * @returns a TimelockExpiry if the native script can be down cast, otherwise, undefined.
+   */
+  asTimelockExpiry(): TimelockExpiry | undefined {
+    return this.#timelockExpiry;
+  }
+}