Revert bigint changes

package.json

@@ -32,7 +32,7 @@
   "license": "ISC",
   "homepage": "https://unicitynetwork.github.io/state-transition-sdk/",
   "dependencies": {
-    "@unicitylabs/commons": "2.4.0-rc.d7fa010"
+    "@unicitylabs/commons": "2.4.0-rc.24d6a7c"
   },
   "devDependencies": {
     "@babel/preset-env": "7.27.2",

src/StateTransitionClient.ts

@@ -104,7 +104,7 @@ export class StateTransitionClient {
     { requestId, transactionData }: Commitment<T>,
     inclusionProof: InclusionProof,
   ): Promise<Transaction<T>> {
-    const status = await inclusionProof.verify(requestId.toBigInt());
+    const status = await inclusionProof.verify(requestId);
     if (status != InclusionProofVerificationStatus.OK) {
       throw new Error('Inclusion proof verification failed.');
     }
@@ -180,7 +180,7 @@ export class StateTransitionClient {
     const requestId = await RequestId.create(publicKey, token.state.hash);
     const inclusionProof = await this.client.getInclusionProof(requestId);
     // TODO: Check ownership?
-    return inclusionProof.verify(requestId.toBigInt());
+    return inclusionProof.verify(requestId);
   }
 
   /**

src/predicate/DefaultPredicate.ts

@@ -129,7 +129,7 @@ export abstract class DefaultPredicate implements IPredicate {
 
     // Verify inclusion proof path.
     const requestId = await RequestId.create(this.publicKey, transaction.data.sourceState.hash);
-    const status = await transaction.inclusionProof.verify(requestId.toBigInt());
+    const status = await transaction.inclusionProof.verify(requestId);
     return status === InclusionProofVerificationStatus.OK;
   }
 

src/token/TokenFactory.ts

@@ -115,7 +115,7 @@ export class TokenFactory {
           return false;
         }
 
-        const coinPathResult = await proof.coinTreePath.verify(transaction.data.tokenId.toBigInt());
+        const coinPathResult = await proof.coinTreePath.verify(transaction.data.tokenId.toBitString().toBigInt());
         if (!coinPathResult.result) {
           return false;
         }
@@ -139,7 +139,7 @@ export class TokenFactory {
 
     // Verify inclusion proof path.
     const requestId = await RequestId.create(signingService.publicKey, transaction.data.sourceState.hash);
-    const status = await transaction.inclusionProof.verify(requestId.toBigInt());
+    const status = await transaction.inclusionProof.verify(requestId);
     return status === InclusionProofVerificationStatus.OK;
   }
 }

src/token/TokenId.ts

@@ -1,4 +1,5 @@
 import { CborEncoder } from '@unicitylabs/commons/lib/cbor/CborEncoder.js';
+import { BitString } from '@unicitylabs/commons/lib/util/BitString.js';
 import { HexConverter } from '@unicitylabs/commons/lib/util/HexConverter.js';
 
 /**
@@ -37,9 +38,9 @@ export class TokenId {
   }
 
   /**
-   * Converts the TokenId to a BigInt representation.
+   * Converts the TokenId to a bitstring representation.
    */
-  public toBigInt(): bigint {
-    return BigInt(`0x01${HexConverter.encode(this.toCBOR())}`);
+  public toBitString(): BitString {
+    return new BitString(this.toCBOR());
   }
 }

src/token/fungible/CoinId.ts

@@ -1,5 +1,7 @@
 import { CborDecoder } from '@unicitylabs/commons/lib/cbor/CborDecoder.js';
 import { CborEncoder } from '@unicitylabs/commons/lib/cbor/CborEncoder.js';
+import { BigintConverter } from '@unicitylabs/commons/lib/util/BigintConverter.js';
+import { BitString } from '@unicitylabs/commons/lib/util/BitString.js';
 import { HexConverter } from '@unicitylabs/commons/lib/util/HexConverter.js';
 
 /** Identifier for a fungible coin type. */
@@ -32,7 +34,7 @@ export class CoinId {
    * @param value bigint represantation of coin id
    */
   public static fromBigInt(value: bigint): CoinId {
-    return CoinId.fromCBOR(HexConverter.decode(value.toString(16).slice(1)));
+    return CoinId.fromCBOR(BigintConverter.encode(value).slice(1));
   }
 
   /** Hex string representation. */
@@ -46,9 +48,9 @@ export class CoinId {
   }
 
   /**
-   * Converts the CoinId to a BigInt representation.
+   * Converts the CoinId to a bitstring representation.
    */
-  public toBigInt(): bigint {
-    return BigInt(`0x01${HexConverter.encode(this.toCBOR())}`);
+  public toBitString(): BitString {
+    return new BitString(this.toCBOR());
   }
 }

src/token/fungible/TokenCoinData.ts

@@ -16,9 +16,9 @@ export class TokenCoinData implements ISerializable {
   private readonly _coins: Map<bigint, bigint>;
 
   /**
-   * @param coins Array of coin id and balance pairs
+   * @param coins Array of coin id serialized to bigint and balance pairs
    */
-  public constructor(coins: [bigint, bigint][]) {
+  private constructor(coins: [bigint, bigint][]) {
     this._coins = new Map(coins);
   }
 
@@ -31,8 +31,12 @@ export class TokenCoinData implements ISerializable {
     return new Map(Array.from(this._coins.entries()).map(([key, value]) => [CoinId.fromBigInt(key), value]));
   }
 
+  /**
+   * Create a new coin data object from an array of coin id and balance pairs.
+   * @param coins Array of tuples of CoinId and bigint.
+   */
   public static create(coins: [CoinId, bigint][]): TokenCoinData {
-    return new TokenCoinData(coins.map(([key, value]) => [key.toBigInt(), value]));
+    return new TokenCoinData(coins.map(([key, value]) => [key.toBitString().toBigInt(), value]));
   }
 
   /** Create a coin data object from CBOR. */
@@ -52,37 +56,28 @@ export class TokenCoinData implements ISerializable {
 
   /** Parse from a JSON representation. */
   public static fromJSON(data: unknown): TokenCoinData {
-    if (!Array.isArray(data)) {
+    if (
+      !Array.isArray(data) ||
+      !data.every(
+        (value) =>
+          Array.isArray(value) && value.length === 2 && typeof value[0] === 'string' && typeof value[1] === 'string',
+      )
+    ) {
       throw new Error('Invalid coin data JSON format');
     }
 
     const coins: [bigint, bigint][] = [];
 
-    // Helper function to safely parse values that might have been corrupted by JSON.stringify()
-    const parseValue = (v: unknown): bigint => {
-      if (typeof v === 'bigint') return v;
-      if (typeof v === 'string' || typeof v === 'number') return BigInt(v);
-      if (v === null) {
-        throw new Error(`Cannot convert null to BigInt. This indicates a JSON serialization issue with BigInt values.`);
-      }
-      if (typeof v === 'object') {
-        throw new Error(
-          `Cannot convert object to BigInt. This indicates a JSON serialization issue with BigInt values. Received: ${JSON.stringify(v)}`,
-        );
-      }
-      throw new Error(`Unsupported type for BigInt conversion: ${typeof v}. Expected string, number, or bigint.`);
-    };
-
     for (const [key, value] of data) {
-      coins.push([parseValue(key), parseValue(value)]);
+      coins.push([BigInt(key), BigInt(value)]);
     }
 
     return new TokenCoinData(coins);
   }
 
   /** Get the balance of a specific coin. */
   public get(coinId: CoinId): bigint | undefined {
-    return this._coins.get(coinId.toBigInt());
+    return this._coins.get(coinId.toBitString().toBigInt());
   }
 
   /** Get the balance of a coin by its internal map key. */

src/transaction/OfflineTransaction.ts

@@ -14,7 +14,6 @@ import { TokenJsonDeserializer } from '../serializer/token/TokenJsonDeserializer
 import { ITokenJson, Token } from '../token/Token.js';
 import { TokenFactory } from '../token/TokenFactory.js';
 import { TokenState } from '../token/TokenState.js';
-import { JsonUtils } from '../utils/JsonUtils.js';
 
 /** JSON representation of an {@link OfflineTransaction}. */
 export interface IOfflineTransactionJson {
@@ -80,18 +79,6 @@ export class OfflineTransaction implements ISerializable {
     return new OfflineTransaction(offlineCommitment, token);
   }
 
-  /**
-   * Create OfflineTransaction from JSON string.
-   * This method can handle JSON strings that were created with toJSONString().
-   *
-   * @param jsonString JSON string representation
-   * @returns Promise<OfflineTransaction>
-   */
-  public static fromJSONString(jsonString: string): Promise<OfflineTransaction> {
-    const parsed = JsonUtils.parse(jsonString);
-    return OfflineTransaction.fromJSON(parsed);
-  }
-
   /**
    * Type guard to check if data is valid OfflineTransaction JSON.
    * @param data Data to validate
@@ -130,18 +117,4 @@ export class OfflineTransaction implements ISerializable {
       token: this.token.toJSON(),
     };
   }
-
-  /**
-   * Serialize to JSON string with BigInt support.
-   * This method handles potential BigInt values that might exist in the object graph
-   * and converts them to strings to prevent JSON serialization errors.
-   *
-   * Use this method when you need to serialize for actual transfer (e.g., NFC, file, etc.).
-   *
-   * @param space Optional spacing for formatting
-   * @returns JSON string with BigInt values safely converted
-   */
-  public toJSONString(space?: string | number): string {
-    return JsonUtils.safeStringify(this, space);
-  }
 }

src/transaction/TokenSplitBuilder.ts

@@ -52,7 +52,7 @@ class SplitToken {
       throw new Error('Amount must be greater than zero');
     }
 
-    this._coins.set(coinId.toBigInt(), amount);
+    this._coins.set(coinId.toBitString().toBigInt(), amount);
     return this;
   }
 }
@@ -80,7 +80,7 @@ class TokenSplitData {
 
     const transactions: MintTransactionData<SplitMintReason>[] = [];
     for (const [tokenId, splitToken] of this.tokens.entries()) {
-      const coinData: [bigint, bigint][] = [];
+      const coinData: [CoinId, bigint][] = [];
       const proofs = new Map<bigint, SplitMintReasonProof>();
       for (const [coinId, amount] of splitToken.coins.entries()) {
         proofs.set(
@@ -90,15 +90,15 @@ class TokenSplitData {
             this._coinTrees.get(coinId)?.getPath(tokenId) as MerkleSumTreePath,
           ),
         );
-        coinData.push([coinId, amount]);
+        coinData.push([CoinId.fromBigInt(coinId), amount]);
       }
 
       transactions.push(
         await MintTransactionData.create(
           splitToken.tokenId,
           splitToken.tokenType,
           splitToken.data,
-          new TokenCoinData(coinData),
+          TokenCoinData.create(coinData),
           splitToken.recipient,
           splitToken.salt,
           splitToken.dataHash,
@@ -122,12 +122,12 @@ export class TokenSplitBuilder {
     dataHash: DataHash,
     salt: Uint8Array,
   ): SplitToken {
-    if (this.tokens.has(id.toBigInt())) {
+    if (this.tokens.has(id.toBitString().toBigInt())) {
       throw new Error('Token already exists in split request');
     }
 
     const builder = new SplitToken(id, type, data, recipient, dataHash, salt);
-    this.tokens.set(id.toBigInt(), builder);
+    this.tokens.set(id.toBitString().toBigInt(), builder);
     return builder;
   }
 

src/utils/InclusionProofUtils.ts

@@ -37,7 +37,7 @@ export async function waitInclusionProof(
   while (true) {
     try {
       const inclusionProof = await client.getInclusionProof(commitment);
-      if ((await inclusionProof.verify(commitment.requestId.toBigInt())) === InclusionProofVerificationStatus.OK) {
+      if ((await inclusionProof.verify(commitment.requestId)) === InclusionProofVerificationStatus.OK) {
         return inclusionProof;
       }
     } catch (err) {