lib/contract_spec.js

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.ContractSpec = void 0;
var _stellarBase = require("stellar-base");
/**
 * Provides a ContractSpec class which can contains the XDR types defined by the contract.
 * This allows the class to be used to convert between native and raw `xdr.ScVal`s.
 *
 * @example
 * const specEntries = [...]; // XDR spec entries of a smart contract
 * const contractSpec = new ContractSpec(specEntries);
 *
 * // Convert native value to ScVal
 * const args = {
 *   arg1: 'value1',
 *   arg2: 1234
 * };
 * const scArgs = contractSpec.funcArgsToScVals('funcName', args);
 *
 * // Call contract
 * const resultScv = await callContract(contractId, 'funcName', scArgs);
 *
 * // Convert result ScVal back to native value
 * const result = contractSpec.funcResToNative('funcName', resultScv);
 *
 * console.log(result); // {success: true}
 */
class ContractSpec {
  entries = [];

  /**
   * Constructs a new ContractSpec from an array of XDR spec entries.
   *
   * @param {xdr.ScSpecEntry[] | string[]} entries the XDR spec entries
   *
   * @throws {Error} if entries is invalid
   */
  constructor(entries) {
    if (entries.length == 0) {
      throw new Error('Contract spec must have at least one entry');
    }
    let entry = entries[0];
    if (typeof entry === 'string') {
      this.entries = entries.map(s => _stellarBase.xdr.ScSpecEntry.fromXDR(s, 'base64'));
    } else {
      this.entries = entries;
    }
  }
  /**
   * Gets the XDR function spec for the given function name.
   *
   * @param {string} name the name of the function
   * @returns {xdr.ScSpecFunctionV0} the function spec
   *
   * @throws {Error} if no function with the given name exists
   */
  getFunc(name) {
    let entry = this.findEntry(name);
    if (entry.switch().value !== _stellarBase.xdr.ScSpecEntryKind.scSpecEntryFunctionV0().value) {
      throw new Error(`${name} is not a function`);
    }
    return entry.value();
  }

  /**
   * Converts native JS arguments to ScVals for calling a contract function.
   *
   * @param {string} name the name of the function
   * @param {Object} args the arguments object
   * @returns {xdr.ScVal[]} the converted arguments
   *
   * @throws {Error} if argument is missing or incorrect type
   *
   * @example
   * ```js
   * const args = {
   *   arg1: 'value1',
   *   arg2: 1234
   * };
   * const scArgs = contractSpec.funcArgsToScVals('funcName', args);
   * ```
   */
  funcArgsToScVals(name, args) {
    let fn = this.getFunc(name);
    return fn.inputs().map(input => this.nativeToScVal(readObj(args, input), input.type()));
  }

  /**
   * Converts the result ScVal of a function call to a native JS value.
   *
   * @param {string} name the name of the function
   * @param {xdr.ScVal | string} val_or_base64 the result ScVal or base64 encoded string
   * @returns {any} the converted native value
   *
   * @throws {Error} if return type mismatch or invalid input
   *
   * @example
   * ```js
   * const resultScv = 'AAA=='; // Base64 encoded ScVal
   * const result = contractSpec.funcResToNative('funcName', resultScv);
   * ```
   */
  funcResToNative(name, val_or_base64) {
    let val = typeof val_or_base64 === 'string' ? _stellarBase.xdr.ScVal.fromXDR(val_or_base64, 'base64') : val_or_base64;
    let func = this.getFunc(name);
    let outputs = func.outputs();
    if (outputs.length === 0) {
      let type = val.switch();
      if (type.value !== _stellarBase.xdr.ScValType.scvVoid().value) {
        throw new Error(`Expected void, got ${type.name}`);
      }
      return null;
    }
    if (outputs.length > 1) {
      throw new Error(`Multiple outputs not supported`);
    }
    let output = outputs[0];
    if (output.switch().value === _stellarBase.xdr.ScSpecType.scSpecTypeResult().value) {
      return this.scValToNative(val, output.result().okType());
    }
    return this.scValToNative(val, output);
  }

  /**
   * Finds the XDR spec entry for the given name.
   *
   * @param {string} name the name to find
   * @returns {xdr.ScSpecEntry} the entry
   *
   * @throws {Error} if no entry with the given name exists
   */
  findEntry(name) {
    let entry = this.entries.find(entry => entry.value().name().toString() === name);
    if (!entry) {
      throw new Error(`no such entry: ${name}`);
    }
    return entry;
  }

  /**
   * Converts a native JS value to an ScVal based on the given type.
   *
   * @param {any} val the native JS value
   * @param {xdr.ScSpecTypeDef} [ty] the expected type
   * @returns {xdr.ScVal} the converted ScVal
   *
   * @throws {Error} if value cannot be converted to the given type
   */
  nativeToScVal(val, ty) {
    let t = ty.switch();
    let value = t.value;
    if (t.value === _stellarBase.xdr.ScSpecType.scSpecTypeUdt().value) {
      let udt = ty.value();
      return this.nativeToUdt(val, udt.name().toString());
    }
    if (value === _stellarBase.xdr.ScSpecType.scSpecTypeOption().value) {
      let opt = ty.value();
      if (val === undefined) {
        return _stellarBase.xdr.ScVal.scvVoid();
      }
      return this.nativeToScVal(val, opt.valueType());
    }
    switch (typeof val) {
      case 'object':
        {
          var _val$constructor;
          if (val === null) {
            switch (value) {
              case _stellarBase.xdr.ScSpecType.scSpecTypeVoid().value:
                return _stellarBase.xdr.ScVal.scvVoid();
              default:
                throw new TypeError(`Type ${ty} was not void, but value was null`);
            }
          }
          if (val instanceof _stellarBase.xdr.ScVal) {
            return val; // should we copy?
          }
          if (val instanceof _stellarBase.Address) {
            if (ty.switch().value !== _stellarBase.xdr.ScSpecType.scSpecTypeAddress().value) {
              throw new TypeError(`Type ${ty} was not address, but value was Address`);
            }
            return val.toScVal();
          }
          if (val instanceof _stellarBase.Contract) {
            if (ty.switch().value !== _stellarBase.xdr.ScSpecType.scSpecTypeAddress().value) {
              throw new TypeError(`Type ${ty} was not address, but value was Address`);
            }
            return val.address().toScVal();
          }
          if (val instanceof Uint8Array || Buffer.isBuffer(val)) {
            const copy = Uint8Array.from(val);
            switch (value) {
              case _stellarBase.xdr.ScSpecType.scSpecTypeBytesN().value:
                {
                  let bytes_n = ty.value();
                  if (copy.length !== bytes_n.n()) {
                    throw new TypeError(`expected ${bytes_n.n()} bytes, but got ${copy.length}`);
                  }
                  //@ts-ignore
                  return _stellarBase.xdr.ScVal.scvBytes(copy);
                }
              case _stellarBase.xdr.ScSpecType.scSpecTypeBytes().value:
                //@ts-ignore
                return _stellarBase.xdr.ScVal.scvBytes(copy);
              default:
                throw new TypeError(`invalid type (${ty}) specified for Bytes and BytesN`);
            }
          }
          if (Array.isArray(val)) {
            if (_stellarBase.xdr.ScSpecType.scSpecTypeVec().value === value) {
              let vec = ty.value();
              let elementType = vec.elementType();
              return _stellarBase.xdr.ScVal.scvVec(val.map(v => this.nativeToScVal(v, elementType)));
            } else if (_stellarBase.xdr.ScSpecType.scSpecTypeTuple().value === value) {
              let tup = ty.value();
              let valTypes = tup.valueTypes();
              if (val.length !== valTypes.length) {
                throw new TypeError(`Tuple expects ${valTypes.length} values, but ${val.length} were provided`);
              }
              return _stellarBase.xdr.ScVal.scvVec(val.map((v, i) => this.nativeToScVal(v, valTypes[i])));
            } else {
              throw new TypeError(`Type ${ty} was not vec, but value was Array`);
            }
          }
          if (val.constructor === Map) {
            if (value !== _stellarBase.xdr.ScSpecType.scSpecTypeMap().value) {
              throw new TypeError(`Type ${ty} was not map, but value was Map`);
            }
            let scMap = ty.value();
            let map = val;
            let entries = [];
            let values = map.entries();
            let res = values.next();
            while (!res.done) {
              let [k, v] = res.value;
              let key = this.nativeToScVal(k, scMap.keyType());
              let val = this.nativeToScVal(v, scMap.valueType());
              entries.push(new _stellarBase.xdr.ScMapEntry({
                key,
                val
              }));
              res = values.next();
            }
            return _stellarBase.xdr.ScVal.scvMap(entries);
          }
          if ((((_val$constructor = val.constructor) === null || _val$constructor === void 0 ? void 0 : _val$constructor.name) ?? '') !== 'Object') {
            var _val$constructor2;
            throw new TypeError(`cannot interpret ${(_val$constructor2 = val.constructor) === null || _val$constructor2 === void 0 ? void 0 : _val$constructor2.name} value as ScVal (${JSON.stringify(val)})`);
          }
          throw new TypeError(`Received object ${val}  did not match the provided type ${ty}`);
        }
      case 'number':
      case 'bigint':
        {
          switch (value) {
            case _stellarBase.xdr.ScSpecType.scSpecTypeU32().value:
              return _stellarBase.xdr.ScVal.scvU32(val);
            case _stellarBase.xdr.ScSpecType.scSpecTypeI32().value:
              return _stellarBase.xdr.ScVal.scvI32(val);
            case _stellarBase.xdr.ScSpecType.scSpecTypeU64().value:
            case _stellarBase.xdr.ScSpecType.scSpecTypeI64().value:
            case _stellarBase.xdr.ScSpecType.scSpecTypeU128().value:
            case _stellarBase.xdr.ScSpecType.scSpecTypeI128().value:
            case _stellarBase.xdr.ScSpecType.scSpecTypeU256().value:
            case _stellarBase.xdr.ScSpecType.scSpecTypeI256().value:
              {
                const intType = t.name.substring(10).toLowerCase();
                return new _stellarBase.XdrLargeInt(intType, val).toScVal();
              }
            default:
              throw new TypeError(`invalid type (${ty}) specified for integer`);
          }
        }
      case 'string':
        return stringToScVal(val, t);
      case 'boolean':
        {
          if (value !== _stellarBase.xdr.ScSpecType.scSpecTypeBool().value) {
            throw TypeError(`Type ${ty} was not bool, but value was bool`);
          }
          return _stellarBase.xdr.ScVal.scvBool(val);
        }
      case 'undefined':
        {
          if (!ty) {
            return _stellarBase.xdr.ScVal.scvVoid();
          }
          switch (value) {
            case _stellarBase.xdr.ScSpecType.scSpecTypeVoid().value:
            case _stellarBase.xdr.ScSpecType.scSpecTypeOption().value:
              return _stellarBase.xdr.ScVal.scvVoid();
            default:
              throw new TypeError(`Type ${ty} was not void, but value was undefined`);
          }
        }
      case 'function':
        // FIXME: Is this too helpful?
        return this.nativeToScVal(val(), ty);
      default:
        throw new TypeError(`failed to convert typeof ${typeof val} (${val})`);
    }
  }
  nativeToUdt(val, name) {
    let entry = this.findEntry(name);
    switch (entry.switch()) {
      case _stellarBase.xdr.ScSpecEntryKind.scSpecEntryUdtEnumV0():
        if (typeof val !== 'number') {
          throw new TypeError(`expected number for enum ${name}, but got ${typeof val}`);
        }
        return this.nativeToEnum(val, entry.value());
      case _stellarBase.xdr.ScSpecEntryKind.scSpecEntryUdtStructV0():
        return this.nativeToStruct(val, entry.value());
      case _stellarBase.xdr.ScSpecEntryKind.scSpecEntryUdtUnionV0():
        return this.nativeToUnion(val, entry.value());
      default:
        throw new Error(`failed to parse udt ${name}`);
    }
  }
  nativeToUnion(val, union_) {
    let entry_name = val.tag;
    let case_ = union_.cases().find(entry => {
      let case_ = entry.value().name().toString();
      return case_ === entry_name;
    });
    if (!case_) {
      throw new TypeError(`no such enum entry: ${entry_name} in ${union_}`);
    }
    let key = _stellarBase.xdr.ScVal.scvSymbol(entry_name);
    switch (case_.switch()) {
      case _stellarBase.xdr.ScSpecUdtUnionCaseV0Kind.scSpecUdtUnionCaseVoidV0():
        {
          return _stellarBase.xdr.ScVal.scvVec([key]);
        }
      case _stellarBase.xdr.ScSpecUdtUnionCaseV0Kind.scSpecUdtUnionCaseTupleV0():
        {
          let types = case_.value().type();
          // if (types.length == 1) {
          //   return xdr.ScVal.scvVec([
          //     key,
          //     this.nativeToScVal(val.values, types[0]),
          //   ]);
          // }
          if (Array.isArray(val.values)) {
            if (val.values.length != types.length) {
              throw new TypeError(`union ${union_} expects ${types.length} values, but got ${val.values.length}`);
            }
            let scvals = val.values.map((v, i) => this.nativeToScVal(v, types[i]));
            scvals.unshift(key);
            return _stellarBase.xdr.ScVal.scvVec(scvals);
          }
          throw new Error(`failed to parse union case ${case_} with ${val}`);
        }
      default:
        throw new Error(`failed to parse union ${union_} with ${val}`);
    }

    // enum_.cases()
  }
  nativeToStruct(val, struct) {
    let fields = struct.fields();
    if (fields.some(isNumeric)) {
      if (!fields.every(isNumeric)) {
        throw new Error('mixed numeric and non-numeric field names are not allowed');
      }
      return _stellarBase.xdr.ScVal.scvVec(fields.map((_, i) => this.nativeToScVal(val[i], fields[i].type())));
    }
    return _stellarBase.xdr.ScVal.scvMap(fields.map(field => {
      let name = field.name().toString();
      return new _stellarBase.xdr.ScMapEntry({
        key: this.nativeToScVal(name, _stellarBase.xdr.ScSpecTypeDef.scSpecTypeSymbol()),
        val: this.nativeToScVal(val[name], field.type())
      });
    }));
  }
  nativeToEnum(val, enum_) {
    if (enum_.cases().some(entry => entry.value() === val)) {
      return _stellarBase.xdr.ScVal.scvU32(val);
    }
    throw new TypeError(`no such enum entry: ${val} in ${enum_}`);
  }

  /**
   * Converts an base64 encoded ScVal back to a native JS value based on the given type.
   *
   * @param {string} scv the base64 encoded ScVal
   * @param {xdr.ScSpecTypeDef} typeDef the expected type
   * @returns {any} the converted native JS value
   *
   * @throws {Error} if ScVal cannot be converted to the given type
   */
  scValStrToNative(scv, typeDef) {
    return this.scValToNative(_stellarBase.xdr.ScVal.fromXDR(scv, 'base64'), typeDef);
  }

  /**
   * Converts an ScVal back to a native JS value based on the given type.
   *
   * @param {xdr.ScVal} scv the ScVal
   * @param {xdr.ScSpecTypeDef} typeDef the expected type
   * @returns {any} the converted native JS value
   *
   * @throws {Error} if ScVal cannot be converted to the given type
   */
  scValToNative(scv, typeDef) {
    let t = typeDef.switch();
    let value = t.value;
    if (value === _stellarBase.xdr.ScSpecType.scSpecTypeUdt().value) {
      return this.scValUdtToNative(scv, typeDef.value());
    }
    // we use the verbose xdr.ScValType.<type>.value form here because it's faster
    // than string comparisons and the underlying constants never need to be
    // updated
    switch (scv.switch().value) {
      case _stellarBase.xdr.ScValType.scvVoid().value:
        return void 0;

      // these can be converted to bigints directly
      case _stellarBase.xdr.ScValType.scvU64().value:
      case _stellarBase.xdr.ScValType.scvI64().value:
      // these can be parsed by internal abstractions note that this can also
      // handle the above two cases, but it's not as efficient (another
      // type-check, parsing, etc.)
      case _stellarBase.xdr.ScValType.scvU128().value:
      case _stellarBase.xdr.ScValType.scvI128().value:
      case _stellarBase.xdr.ScValType.scvU256().value:
      case _stellarBase.xdr.ScValType.scvI256().value:
        return (0, _stellarBase.scValToBigInt)(scv);
      case _stellarBase.xdr.ScValType.scvVec().value:
        {
          if (value == _stellarBase.xdr.ScSpecType.scSpecTypeVec().value) {
            let vec = typeDef.value();
            return (scv.vec() ?? []).map(elm => this.scValToNative(elm, vec.elementType()));
          } else if (value == _stellarBase.xdr.ScSpecType.scSpecTypeTuple().value) {
            let tuple = typeDef.value();
            let valTypes = tuple.valueTypes();
            return (scv.vec() ?? []).map((elm, i) => this.scValToNative(elm, valTypes[i]));
          }
          throw new TypeError(`Type ${typeDef} was not vec, but ${scv} is`);
        }
      case _stellarBase.xdr.ScValType.scvAddress().value:
        return _stellarBase.Address.fromScVal(scv);
      case _stellarBase.xdr.ScValType.scvMap().value:
        {
          let map = scv.map() ?? [];
          if (value == _stellarBase.xdr.ScSpecType.scSpecTypeMap().value) {
            let type_ = typeDef.value();
            let keyType = type_.keyType();
            let valueType = type_.valueType();
            return new Map(map.map(entry => [this.scValToNative(entry.key(), keyType), this.scValToNative(entry.val(), valueType)]));
          }
          throw new TypeError(`ScSpecType ${t.name} was not map, but ${JSON.stringify(scv, null, 2)} is`);
        }

      // these return the primitive type directly
      case _stellarBase.xdr.ScValType.scvBool().value:
      case _stellarBase.xdr.ScValType.scvU32().value:
      case _stellarBase.xdr.ScValType.scvI32().value:
      case _stellarBase.xdr.ScValType.scvBytes().value:
        return scv.value();
      case _stellarBase.xdr.ScValType.scvString().value:
      case _stellarBase.xdr.ScValType.scvSymbol().value:
        {
          var _scv$value;
          if (value !== _stellarBase.xdr.ScSpecType.scSpecTypeString().value && value !== _stellarBase.xdr.ScSpecType.scSpecTypeSymbol().value) {
            throw new Error(`ScSpecType ${t.name} was not string or symbol, but ${JSON.stringify(scv, null, 2)} is`);
          }
          return (_scv$value = scv.value()) === null || _scv$value === void 0 ? void 0 : _scv$value.toString();
        }

      // these can be converted to bigint
      case _stellarBase.xdr.ScValType.scvTimepoint().value:
      case _stellarBase.xdr.ScValType.scvDuration().value:
        return (0, _stellarBase.scValToBigInt)(_stellarBase.xdr.ScVal.scvU64(scv.value()));

      // in the fallthrough case, just return the underlying value directly
      default:
        throw new TypeError(`failed to convert ${JSON.stringify(scv, null, 2)} to native type from type ${t.name}`);
    }
  }
  scValUdtToNative(scv, udt) {
    let entry = this.findEntry(udt.name().toString());
    switch (entry.switch()) {
      case _stellarBase.xdr.ScSpecEntryKind.scSpecEntryUdtEnumV0():
        return this.enumToNative(scv, entry.value());
      case _stellarBase.xdr.ScSpecEntryKind.scSpecEntryUdtStructV0():
        return this.structToNative(scv, entry.value());
      case _stellarBase.xdr.ScSpecEntryKind.scSpecEntryUdtUnionV0():
        return this.unionToNative(scv, entry.value());
      default:
        throw new Error(`failed to parse udt ${udt.name().toString()}: ${entry}`);
    }
  }
  unionToNative(val, udt) {
    let vec = val.vec();
    if (!vec) {
      throw new Error(`${JSON.stringify(val, null, 2)} is not a vec`);
    }
    if (vec.length === 0 && udt.cases.length !== 0) {
      throw new Error(`${val} has length 0, but the there are at least one case in the union`);
    }
    let name = vec[0].sym().toString();
    if (vec[0].switch().value != _stellarBase.xdr.ScValType.scvSymbol().value) {
      throw new Error(`{vec[0]} is not a symbol`);
    }
    let entry = udt.cases().find(findCase(name));
    if (!entry) {
      throw new Error(`failed to find entry ${name} in union {udt.name().toString()}`);
    }
    let res = {
      tag: name,
      values: undefined
    };
    if (entry.switch().value === _stellarBase.xdr.ScSpecUdtUnionCaseV0Kind.scSpecUdtUnionCaseTupleV0().value) {
      let tuple = entry.value();
      let ty = tuple.type();
      //@ts-ignore
      let values = [];
      for (let i = 0; i < ty.length; i++) {
        let v = this.scValToNative(vec[i + 1], ty[i]);
        values.push(v);
      }
      let r = {
        tag: name,
        values
      };
      return r;
    }
    return res;
  }
  structToNative(val, udt) {
    var _val$map;
    let res = {};
    let fields = udt.fields();
    if (fields.some(isNumeric)) {
      var _val$vec;
      let r = (_val$vec = val.vec()) === null || _val$vec === void 0 ? void 0 : _val$vec.map((entry, i) => this.scValToNative(entry, fields[i].type()));
      return r;
    }
    (_val$map = val.map()) === null || _val$map === void 0 || _val$map.forEach((entry, i) => {
      let field = fields[i];
      res[field.name().toString()] = this.scValToNative(entry.val(), field.type());
    });
    return res;
  }
  enumToNative(scv, udt) {
    if (scv.switch().value !== _stellarBase.xdr.ScValType.scvU32().value) {
      throw new Error(`Enum must have a u32 value`);
    }
    let num = scv.value();
    if (udt.cases().some(entry => entry.value() === num)) {}
    return num;
  }
}
exports.ContractSpec = ContractSpec;
function stringToScVal(str, ty) {
  switch (ty.value) {
    case _stellarBase.xdr.ScSpecType.scSpecTypeString().value:
      return _stellarBase.xdr.ScVal.scvString(str);
    case _stellarBase.xdr.ScSpecType.scSpecTypeSymbol().value:
      return _stellarBase.xdr.ScVal.scvSymbol(str);
    case _stellarBase.xdr.ScSpecType.scSpecTypeAddress().value:
      {
        let addr = _stellarBase.Address.fromString(str);
        return _stellarBase.xdr.ScVal.scvAddress(addr.toScAddress());
      }
    default:
      throw new TypeError(`invalid type ${ty.name} specified for string value`);
  }
}
function isNumeric(field) {
  return /^\d+$/.test(field.name().toString());
}
function findCase(name) {
  return function matches(entry) {
    switch (entry.switch().value) {
      case _stellarBase.xdr.ScSpecUdtUnionCaseV0Kind.scSpecUdtUnionCaseTupleV0().value:
        {
          let tuple = entry.value();
          return tuple.name().toString() === name;
        }
      case _stellarBase.xdr.ScSpecUdtUnionCaseV0Kind.scSpecUdtUnionCaseVoidV0().value:
        {
          let void_case = entry.value();
          return void_case.name().toString() === name;
        }
      default:
        return false;
    }
  };
}
function readObj(args, input) {
  let inputName = input.name().toString();
  let entry = Object.entries(args).find(([name, _]) => name === inputName);
  if (!entry) {
    throw new Error(`Missing field ${inputName}`);
  }
  return entry[1];
}