eosjs-serialize.ts

/**
 * @module Serialize
 */
// copyright defined in eosjs/LICENSE.txt

import * as numeric from "./eosjs-numeric";
import { Abi, BlockTaposInfo } from "./eosjs-rpc-interfaces";

/** A field in an abi */
export interface Field {
    /** Field name */
    name: string;

    /** Type name in string form */
    typeName: string;

    /** Type of the field */
    type: Type;
}

/** Options for serialize() and deserialize() */
export interface SerializerOptions {
    bytesAsUint8Array?: boolean;
}

/** State for serialize() and deserialize() */
export class SerializerState {
    public options: SerializerOptions;

    /** Have any binary extensions been skipped? */
    public skippedBinaryExtension = false;

    constructor(options: SerializerOptions = {}) {
        this.options = options;
    }
}

/** A type in an abi */
export interface Type {
    /** Type name */
    name: string;

    /** Type name this is an alias of, if any */
    aliasOfName: string;

    /** Type this is an array of, if any */
    arrayOf: Type;

    /** Type this is an optional of, if any */
    optionalOf: Type;

    /** Marks binary extension fields */
    extensionOf?: Type;

    /** Base name of this type, if this is a struct */
    baseName: string;

    /** Base of this type, if this is a struct */
    base: Type;

    /** Contained fields, if this is a struct */
    fields: Field[];

    /** Convert `data` to binary form and store in `buffer` */
    serialize: (buffer: SerialBuffer, data: any, state?: SerializerState, allowExtensions?: boolean) => void;

    /** Convert data in `buffer` from binary form */
    deserialize: (buffer: SerialBuffer, state?: SerializerState, allowExtensions?: boolean) => any;
}

/** Structural representation of a symbol */
export interface Symbol {
    /** Name of the symbol, not including precision */
    name: string;

    /** Number of digits after the decimal point */
    precision: number;
}

export interface Contract {
    actions: Map<string, Type>;
    types: Map<string, Type>;
}

export interface Authorization {
    actor: string;
    permission: string;
}

/** Action with data in structured form */
export interface Action {
    account: string;
    name: string;
    authorization: Authorization[];
    data: any;
}

/** Action with data in serialized hex form */
export interface SerializedAction {
    account: string;
    name: string;
    authorization: Authorization[];
    data: string;
}

/** Serialize and deserialize data */
export class SerialBuffer {
    /** Amount of valid data in `array` */
    public length: number;

    /** Data in serialized (binary) form */
    public array: Uint8Array;

    /** Current position while reading (deserializing) */
    public readPos = 0;

    public textEncoder: TextEncoder;
    public textDecoder: TextDecoder;

    /**
     * @param __namedParameters
     *    * `array`: `null` if serializing, or binary data to deserialize
     *    * `textEncoder`: `TextEncoder` instance to use. Pass in `null` if running in a browser
     *    * `textDecoder`: `TextDecider` instance to use. Pass in `null` if running in a browser
     */
    constructor({ textEncoder, textDecoder, array } = {} as
        { textEncoder?: TextEncoder, textDecoder?: TextDecoder, array?: Uint8Array }) {
        this.array = array || new Uint8Array(1024);
        this.length = array ? array.length : 0;
        this.textEncoder = textEncoder || new TextEncoder();
        this.textDecoder = textDecoder || new TextDecoder("utf-8", { fatal: true });
    }

    /** Resize `array` if needed to have at least `size` bytes free */
    public reserve(size: number) {
        if (this.length + size <= this.array.length) {
            return;
        }
        let l = this.array.length;
        while (this.length + size > l) {
            l = Math.ceil(l * 1.5);
        }
        const newArray = new Uint8Array(l);
        newArray.set(this.array);
        this.array = newArray;
    }

    /** Is there data available to read? */
    public haveReadData() {
        return this.readPos < this.length;
    }

    /** Restart reading from the beginning */
    public restartRead() {
        this.readPos = 0;
    }

    /** Return data with excess storage trimmed away */
    public asUint8Array() {
        return new Uint8Array(this.array.buffer, this.array.byteOffset, this.length);
    }

    /** Append bytes */
    public pushArray(v: number[] | Uint8Array) {
        this.reserve(v.length);
        this.array.set(v, this.length);
        this.length += v.length;
    }

    /** Append bytes */
    public push(...v: number[]) {
        this.pushArray(v);
    }

    /** Get a single byte */
    public get() {
        if (this.readPos < this.length) {
            return this.array[this.readPos++];
        }
        throw new Error("Read past end of buffer");
    }

    /** Append bytes in `v`. Throws if `len` doesn't match `v.length` */
    public pushUint8ArrayChecked(v: Uint8Array, len: number) {
        if (v.length !== len) {
            throw new Error("Binary data has incorrect size");
        }
        this.pushArray(v);
    }

    /** Get `len` bytes */
    public getUint8Array(len: number) {
        if (this.readPos + len > this.length) {
            throw new Error("Read past end of buffer");
        }
        const result = new Uint8Array(this.array.buffer, this.array.byteOffset + this.readPos, len);
        this.readPos += len;
        return result;
    }

    /** Append a `uint16` */
    public pushUint16(v: number) {
        this.push((v >> 0) & 0xff, (v >> 8) & 0xff);
    }

    /** Get a `uint16` */
    public getUint16() {
        let v = 0;
        v |= this.get() << 0;
        v |= this.get() << 8;
        return v;
    }

    /** Append a `uint32` */
    public pushUint32(v: number) {
        this.push((v >> 0) & 0xff, (v >> 8) & 0xff, (v >> 16) & 0xff, (v >> 24) & 0xff);
    }

    /** Get a `uint32` */
    public getUint32() {
        let v = 0;
        v |= this.get() << 0;
        v |= this.get() << 8;
        v |= this.get() << 16;
        v |= this.get() << 24;
        return v >>> 0;
    }

    /** Append a `uint64`. *Caution*: `number` only has 53 bits of precision */
    public pushNumberAsUint64(v: number) {
        this.pushUint32(v >>> 0);
        this.pushUint32(Math.floor(v / 0x10000_0000) >>> 0);
    }

    /**
     * Get a `uint64` as a `number`. *Caution*: `number` only has 53 bits of precision; some values will change.
     * `numeric.binaryToDecimal(serialBuffer.getUint8Array(8))` recommended instead
     */
    public getUint64AsNumber() {
        const low = this.getUint32();
        const high = this.getUint32();
        return (high >>> 0) * 0x10000_0000 + (low >>> 0);
    }

    /** Append a `varuint32` */
    public pushVaruint32(v: number) {
        while (true) {
            if (v >>> 7) {
                this.push(0x80 | (v & 0x7f));
                v = v >>> 7;
            } else {
                this.push(v);
                break;
            }
        }
    }

    /** Get a `varuint32` */
    public getVaruint32() {
        let v = 0;
        let bit = 0;
        while (true) {
            const b = this.get();
            v |= (b & 0x7f) << bit;
            bit += 7;
            if (!(b & 0x80)) {
                break;
            }
        }
        return v >>> 0;
    }

    /** Append a `varint32` */
    public pushVarint32(v: number) {
        this.pushVaruint32((v << 1) ^ (v >> 31));
    }

    /** Get a `varint32` */
    public getVarint32() {
        const v = this.getVaruint32();
        if (v & 1) {
            return ((~v) >> 1) | 0x8000_0000;
        } else {
            return v >>> 1;
        }
    }

    /** Append a `float32` */
    public pushFloat32(v: number) {
        this.pushArray(new Uint8Array((new Float32Array([v])).buffer));
    }

    /** Get a `float32` */
    public getFloat32() {
        return new Float32Array(this.getUint8Array(4).slice().buffer)[0];
    }

    /** Append a `float64` */
    public pushFloat64(v: number) {
        this.pushArray(new Uint8Array((new Float64Array([v])).buffer));
    }

    /** Get a `float64` */
    public getFloat64() {
        return new Float64Array(this.getUint8Array(8).slice().buffer)[0];
    }

    /** Append a `name` */
    public pushName(s: string) {
        if (typeof s !== "string") {
            throw new Error("Expected string containing name");
        }
        function charToSymbol(c: number) {
            if (c >= "a".charCodeAt(0) && c <= "z".charCodeAt(0)) {
                return (c - "a".charCodeAt(0)) + 6;
            }
            if (c >= "1".charCodeAt(0) && c <= "5".charCodeAt(0)) {
                return (c - "1".charCodeAt(0)) + 1;
            }
            return 0;
        }
        const a = new Uint8Array(8);
        let bit = 63;
        for (let i = 0; i < s.length; ++i) {
            let c = charToSymbol(s.charCodeAt(i));
            if (bit < 5) {
                c = c << 1;
            }
            for (let j = 4; j >= 0; --j) {
                if (bit >= 0) {
                    a[Math.floor(bit / 8)] |= ((c >> j) & 1) << (bit % 8);
                    --bit;
                }
            }
        }
        this.pushArray(a);
    }

    /** Get a `name` */
    public getName() {
        const a = this.getUint8Array(8);
        let result = "";
        for (let bit = 63; bit >= 0;) {
            let c = 0;
            for (let i = 0; i < 5; ++i) {
                if (bit >= 0) {
                    c = (c << 1) | ((a[Math.floor(bit / 8)] >> (bit % 8)) & 1);
                    --bit;
                }
            }
            if (c >= 6) {
                result += String.fromCharCode(c + "a".charCodeAt(0) - 6);
            } else if (c >= 1) {
                result += String.fromCharCode(c + "1".charCodeAt(0) - 1);
            } else {
                result += ".";
            }
        }
        if (result === ".............") {
            return result;
        }
        while (result.endsWith(".")) {
            result = result.substr(0, result.length - 1);
        }
        return result;
    }

    /** Append length-prefixed binary data */
    public pushBytes(v: number[] | Uint8Array) {
        this.pushVaruint32(v.length);
        this.pushArray(v);
    }

    /** Get length-prefixed binary data */
    public getBytes() {
        return this.getUint8Array(this.getVaruint32());
    }

    /** Append a string */
    public pushString(v: string) {
        this.pushBytes(this.textEncoder.encode(v));
    }

    /** Get a string */
    public getString() {
        return this.textDecoder.decode(this.getBytes());
    }

    /** Append a `symbol_code`. Unlike `symbol`, `symbol_code` doesn't include a precision. */
    public pushSymbolCode(name: string) {
        if (typeof name !== "string") {
            throw new Error("Expected string containing symbol_code");
        }
        const a = [];
        a.push(...this.textEncoder.encode(name));
        while (a.length < 8) {
            a.push(0);
        }
        this.pushArray(a.slice(0, 8));
    }

    /** Get a `symbol_code`. Unlike `symbol`, `symbol_code` doesn't include a precision. */
    public getSymbolCode() {
        const a = this.getUint8Array(8);
        let len;
        for (len = 0; len < a.length; ++len) {
            if (!a[len]) {
                break;
            }
        }
        const name = this.textDecoder.decode(new Uint8Array(a.buffer, a.byteOffset, len));
        return name;
    }

    /** Append a `symbol` */
    public pushSymbol({ name, precision }: { name: string, precision: number }) {
        const a = [precision & 0xff];
        a.push(...this.textEncoder.encode(name));
        while (a.length < 8) {
            a.push(0);
        }
        this.pushArray(a.slice(0, 8));
    }

    /** Get a `symbol` */
    public getSymbol(): { name: string, precision: number } {
        const precision = this.get();
        const a = this.getUint8Array(7);
        let len;
        for (len = 0; len < a.length; ++len) {
            if (!a[len]) {
                break;
            }
        }
        const name = this.textDecoder.decode(new Uint8Array(a.buffer, a.byteOffset, len));
        return { name, precision };
    }

    /** Append an asset */
    public pushAsset(s: string) {
        if (typeof s !== "string") {
            throw new Error("Expected string containing asset");
        }
        s = s.trim();
        let pos = 0;
        let amount = "";
        let precision = 0;
        if (s[pos] === "-") {
            amount += "-";
            ++pos;
        }
        let foundDigit = false;
        while (pos < s.length && s.charCodeAt(pos) >= "0".charCodeAt(0) && s.charCodeAt(pos) <= "9".charCodeAt(0)) {
            foundDigit = true;
            amount += s[pos];
            ++pos;
        }
        if (!foundDigit) {
            throw new Error("Asset must begin with a number");
        }
        if (s[pos] === ".") {
            ++pos;
            while (pos < s.length && s.charCodeAt(pos) >= "0".charCodeAt(0) && s.charCodeAt(pos) <= "9".charCodeAt(0)) {
                amount += s[pos];
                ++precision;
                ++pos;
            }
        }
        const name = s.substr(pos).trim();
        this.pushArray(numeric.signedDecimalToBinary(8, amount));
        this.pushSymbol({ name, precision });
    }

    /** Get an asset */
    public getAsset() {
        const amount = this.getUint8Array(8);
        const { name, precision } = this.getSymbol();
        let s = numeric.signedBinaryToDecimal(amount, precision + 1);
        if (precision) {
            s = s.substr(0, s.length - precision) + "." + s.substr(s.length - precision);
        }
        return s + " " + name;
    }

    /** Append a public key */
    public pushPublicKey(s: string) {
        const key = numeric.stringToPublicKey(s);
        this.push(key.type);
        this.pushArray(key.data);
    }

    /** Get a public key */
    public getPublicKey() {
        const type = this.get();
        const data = this.getUint8Array(numeric.publicKeyDataSize);
        return numeric.publicKeyToString({ type, data });
    }

    /** Append a private key */
    public pushPrivateKey(s: string) {
        const key = numeric.stringToPrivateKey(s);
        this.push(key.type);
        this.pushArray(key.data);
    }

    /** Get a private key */
    public getPrivateKey() {
        const type = this.get();
        const data = this.getUint8Array(numeric.privateKeyDataSize);
        return numeric.privateKeyToString({ type, data });
    }

    /** Append a signature */
    public pushSignature(s: string) {
        const key = numeric.stringToSignature(s);
        this.push(key.type);
        this.pushArray(key.data);
    }

    /** Get a signature */
    public getSignature() {
        const type = this.get();
        const data = this.getUint8Array(numeric.signatureDataSize);
        return numeric.signatureToString({ type, data });
    }
} // SerialBuffer

/** Is this a supported ABI version? */
export function supportedAbiVersion(version: string) {
    return version.startsWith("eosio::abi/1.");
}

function checkDateParse(date: string) {
    const result = Date.parse(date);
    if (Number.isNaN(result)) {
        throw new Error("Invalid time format");
    }
    return result;
}

/** Convert date in ISO format to `time_point` (miliseconds since epoch) */
export function dateToTimePoint(date: string) {
    return Math.round(checkDateParse(date + "Z") * 1000);
}

/** Convert `time_point` (miliseconds since epoch) to date in ISO format */
export function timePointToDate(us: number) {
    const s = (new Date(us / 1000)).toISOString();
    return s.substr(0, s.length - 1);
}

/** Convert date in ISO format to `time_point_sec` (seconds since epoch) */
export function dateToTimePointSec(date: string) {
    return Math.round(checkDateParse(date + "Z") / 1000);
}

/** Convert `time_point_sec` (seconds since epoch) to to date in ISO format */
export function timePointSecToDate(sec: number) {
    const s = (new Date(sec * 1000)).toISOString();
    return s.substr(0, s.length - 1);
}

/** Convert date in ISO format to `block_timestamp_type` (half-seconds since a different epoch) */
export function dateToBlockTimestamp(date: string) {
    return Math.round((checkDateParse(date + "Z") - 946684800000) / 500);
}

/** Convert `block_timestamp_type` (half-seconds since a different epoch) to to date in ISO format */
export function blockTimestampToDate(slot: number) {
    const s = (new Date(slot * 500 + 946684800000)).toISOString();
    return s.substr(0, s.length - 1);
}

/** Convert `string` to `Symbol`. format: `precision,NAME`. */
export function stringToSymbol(s: string): { name: string, precision: number } {
    if (typeof s !== "string") {
        throw new Error("Expected string containing symbol");
    }
    const m = s.match(/^([0-9]+),([A-Z]+)$/);
    if (!m) {
        throw new Error("Invalid symbol");
    }
    return { name: m[2], precision: +m[1] };
}

/** Convert `Symbol` to `string`. format: `precision,NAME`. */
export function symbolToString({ name, precision }: { name: string, precision: number }) {
    return precision + "," + name;
}

/** Convert binary data to hex */
export function arrayToHex(data: Uint8Array) {
    let result = "";
    for (const x of data) {
        result += ("00" + x.toString(16)).slice(-2);
    }
    return result.toUpperCase();
}

/** Convert hex to binary data */
export function hexToUint8Array(hex: string) {
    if (typeof hex !== "string") {
        throw new Error("Expected string containing hex digits");
    }
    if (hex.length % 2) {
        throw new Error("Odd number of hex digits");
    }
    const l = hex.length / 2;
    const result = new Uint8Array(l);
    for (let i = 0; i < l; ++i) {
        const x = parseInt(hex.substr(i * 2, 2), 16);
        if (Number.isNaN(x)) {
            throw new Error("Expected hex string");
        }
        result[i] = x;
    }
    return result;
}

function serializeUnknown(buffer: SerialBuffer, data: any): SerialBuffer {
    throw new Error("Don't know how to serialize " + this.name);
}

function deserializeUnknown(buffer: SerialBuffer): SerialBuffer {
    throw new Error("Don't know how to deserialize " + this.name);
}

function serializeStruct(this: Type, buffer: SerialBuffer, data: any,
                         state = new SerializerState(), allowExtensions = true) {
    if (typeof data !== "object") {
        throw new Error("expected object containing data: " + JSON.stringify(data));
    }
    if (this.base) {
        this.base.serialize(buffer, data, state, allowExtensions);
    }
    for (const field of this.fields) {
        if (field.name in data) {
            if (state.skippedBinaryExtension) {
                throw new Error("unexpected " + this.name + "." + field.name);
            }
            field.type.serialize(
                buffer, data[field.name], state, allowExtensions && field === this.fields[this.fields.length - 1]);
        } else {
            if (allowExtensions && field.type.extensionOf) {
                state.skippedBinaryExtension = true;
            } else {
                throw new Error("missing " + this.name + "." + field.name + " (type=" + field.type.name + ")");
            }
        }
    }
}

function deserializeStruct(this: Type, buffer: SerialBuffer, state = new SerializerState(), allowExtensions = true) {
    let result;
    if (this.base) {
        result = this.base.deserialize(buffer, state, allowExtensions);
    } else {
        result = {};
    }
    for (const field of this.fields) {
        if (allowExtensions && field.type.extensionOf && !buffer.haveReadData()) {
            state.skippedBinaryExtension = true;
        } else {
            result[field.name] = field.type.deserialize(buffer, state, allowExtensions);
        }
    }
    return result;
}

function serializeVariant(this: Type, buffer: SerialBuffer, data: any,
                          state?: SerializerState, allowExtensions?: boolean) {
    if (!Array.isArray(data) || data.length !== 2 || typeof data[0] !== "string") {
        throw new Error('expected variant: ["type", value]');
    }
    const i = this.fields.findIndex((field: Field) => field.name === data[0]);
    if (i < 0) {
        throw new Error(`type "${data[0]}" is not valid for variant`);
    }
    buffer.pushVaruint32(i);
    this.fields[i].type.serialize(buffer, data[1], state, allowExtensions);
}

function deserializeVariant(this: Type, buffer: SerialBuffer, state?: SerializerState, allowExtensions?: boolean) {
    const i = buffer.getVaruint32();
    if (i >= this.fields.length) {
        throw new Error(`type index ${i} is not valid for variant`);
    }
    const field = this.fields[i];
    return [field.name, field.type.deserialize(buffer, state, allowExtensions)];
}

function serializeArray(this: Type, buffer: SerialBuffer, data: any[],
                        state?: SerializerState, allowExtensions?: boolean) {
    buffer.pushVaruint32(data.length);
    for (const item of data) {
        this.arrayOf.serialize(buffer, item, state, false);
    }
}

function deserializeArray(this: Type, buffer: SerialBuffer, state?: SerializerState, allowExtensions?: boolean) {
    const len = buffer.getVaruint32();
    const result = [];
    for (let i = 0; i < len; ++i) {
        result.push(this.arrayOf.deserialize(buffer, state, false));
    }
    return result;
}

function serializeOptional(this: Type, buffer: SerialBuffer, data: any,
                           state?: SerializerState, allowExtensions?: boolean) {
    if (data === null || data === undefined) {
        buffer.push(0);
    } else {
        buffer.push(1);
        this.optionalOf.serialize(buffer, data, state, allowExtensions);
    }
}

function deserializeOptional(this: Type, buffer: SerialBuffer, state?: SerializerState, allowExtensions?: boolean) {
    if (buffer.get()) {
        return this.optionalOf.deserialize(buffer, state, allowExtensions);
    } else {
        return null;
    }
}

function serializeExtension(this: Type, buffer: SerialBuffer, data: any,
                            state?: SerializerState, allowExtensions?: boolean) {
    this.extensionOf.serialize(buffer, data, state, allowExtensions);
}

function deserializeExtension(this: Type, buffer: SerialBuffer, state?: SerializerState, allowExtensions?: boolean) {
    return this.extensionOf.deserialize(buffer, state, allowExtensions);
}

interface CreateTypeArgs {
    name?: string;
    aliasOfName?: string;
    arrayOf?: Type;
    optionalOf?: Type;
    extensionOf?: Type;
    baseName?: string;
    base?: Type;
    fields?: Field[];
    serialize?: (buffer: SerialBuffer, data: any, state?: SerializerState, allowExtensions?: boolean) => void;
    deserialize?: (buffer: SerialBuffer, state?: SerializerState, allowExtensions?: boolean) => any;
}

function createType(attrs: CreateTypeArgs): Type {
    return {
        name: "<missing name>",
        aliasOfName: "",
        arrayOf: null,
        optionalOf: null,
        extensionOf: null,
        baseName: "",
        base: null,
        fields: [],
        serialize: serializeUnknown,
        deserialize: deserializeUnknown,
        ...attrs,
    };
}

function checkRange(orig: number, converted: number) {
    if (Number.isNaN(+orig) || Number.isNaN(+converted) || (typeof orig !== "number" && typeof orig !== "string")) {
        throw new Error("Expected number");
    }
    if (+orig !== +converted) {
        throw new Error("Number is out of range");
    }
    return +orig;
}

/** Create the set of types built-in to the abi format */
export function createInitialTypes(): Map<string, Type> {
    const result: Map<string, Type> = new Map(Object.entries({
        bool: createType({
            name: "bool",
            serialize(buffer: SerialBuffer, data: boolean) {
                if (typeof data !== "boolean") {
                    throw new Error("Expected true or false");
                }
                buffer.push(data ? 1 : 0);
            },
            deserialize(buffer: SerialBuffer) { return !!buffer.get(); },
        }),
        uint8: createType({
            name: "uint8",
            serialize(buffer: SerialBuffer, data: number) { buffer.push(checkRange(data, data & 0xff)); },
            deserialize(buffer: SerialBuffer) { return buffer.get(); },
        }),
        int8: createType({
            name: "int8",
            serialize(buffer: SerialBuffer, data: number) { buffer.push(checkRange(data, data << 24 >> 24)); },
            deserialize(buffer: SerialBuffer) { return buffer.get() << 24 >> 24; },
        }),
        uint16: createType({
            name: "uint16",
            serialize(buffer: SerialBuffer, data: number) { buffer.pushUint16(checkRange(data, data & 0xffff)); },
            deserialize(buffer: SerialBuffer) { return buffer.getUint16(); },
        }),
        int16: createType({
            name: "int16",
            serialize(buffer: SerialBuffer, data: number) { buffer.pushUint16(checkRange(data, data << 16 >> 16)); },
            deserialize(buffer: SerialBuffer) { return buffer.getUint16() << 16 >> 16; },
        }),
        uint32: createType({
            name: "uint32",
            serialize(buffer: SerialBuffer, data: number) { buffer.pushUint32(checkRange(data, data >>> 0)); },
            deserialize(buffer: SerialBuffer) { return buffer.getUint32(); },
        }),
        uint64: createType({
            name: "uint64",
            serialize(buffer: SerialBuffer, data: string | number) {
                buffer.pushArray(numeric.decimalToBinary(8, "" + data));
            },
            deserialize(buffer: SerialBuffer) { return numeric.binaryToDecimal(buffer.getUint8Array(8)); },
        }),
        int64: createType({
            name: "int64",
            serialize(buffer: SerialBuffer, data: string | number) {
                buffer.pushArray(numeric.signedDecimalToBinary(8, "" + data));
            },
            deserialize(buffer: SerialBuffer) { return numeric.signedBinaryToDecimal(buffer.getUint8Array(8)); },
        }),
        int32: createType({
            name: "int32",
            serialize(buffer: SerialBuffer, data: number) { buffer.pushUint32(checkRange(data, data | 0)); },
            deserialize(buffer: SerialBuffer) { return buffer.getUint32() | 0; },
        }),
        varuint32: createType({
            name: "varuint32",
            serialize(buffer: SerialBuffer, data: number) { buffer.pushVaruint32(checkRange(data, data >>> 0)); },
            deserialize(buffer: SerialBuffer) { return buffer.getVaruint32(); },
        }),
        varint32: createType({
            name: "varint32",
            serialize(buffer: SerialBuffer, data: number) { buffer.pushVarint32(checkRange(data, data | 0)); },
            deserialize(buffer: SerialBuffer) { return buffer.getVarint32(); },
        }),
        uint128: createType({
            name: "uint128",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushArray(numeric.decimalToBinary(16, "" + data)); },
            deserialize(buffer: SerialBuffer) { return numeric.binaryToDecimal(buffer.getUint8Array(16)); },
        }),
        int128: createType({
            name: "int128",
            serialize(buffer: SerialBuffer, data: string) {
                buffer.pushArray(numeric.signedDecimalToBinary(16, "" + data));
            },
            deserialize(buffer: SerialBuffer) { return numeric.signedBinaryToDecimal(buffer.getUint8Array(16)); },
        }),
        float32: createType({
            name: "float32",
            serialize(buffer: SerialBuffer, data: number) { buffer.pushFloat32(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getFloat32(); },
        }),
        float64: createType({
            name: "float64",
            serialize(buffer: SerialBuffer, data: number) { buffer.pushFloat64(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getFloat64(); },
        }),
        float128: createType({
            name: "float128",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushUint8ArrayChecked(hexToUint8Array(data), 16); },
            deserialize(buffer: SerialBuffer) { return arrayToHex(buffer.getUint8Array(16)); },
        }),

        bytes: createType({
            name: "bytes",
            serialize(buffer: SerialBuffer, data: string | Uint8Array | number[]) {
                if (data instanceof Uint8Array || Array.isArray(data)) {
                    buffer.pushBytes(data);
                } else {
                    buffer.pushBytes(hexToUint8Array(data));
                }
            },
            deserialize(buffer: SerialBuffer, state?: SerializerState) {
                if (state.options.bytesAsUint8Array) {
                    return buffer.getBytes();
                } else {
                    return arrayToHex(buffer.getBytes());
                }
            },
        }),
        string: createType({
            name: "string",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushString(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getString(); },
        }),
        name: createType({
            name: "name",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushName(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getName(); },
        }),
        time_point: createType({
            name: "time_point",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushNumberAsUint64(dateToTimePoint(data)); },
            deserialize(buffer: SerialBuffer) { return timePointToDate(buffer.getUint64AsNumber()); },
        }),
        time_point_sec: createType({
            name: "time_point_sec",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushUint32(dateToTimePointSec(data)); },
            deserialize(buffer: SerialBuffer) { return timePointSecToDate(buffer.getUint32()); },
        }),
        block_timestamp_type: createType({
            name: "block_timestamp_type",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushUint32(dateToBlockTimestamp(data)); },
            deserialize(buffer: SerialBuffer) { return blockTimestampToDate(buffer.getUint32()); },
        }),
        symbol_code: createType({
            name: "symbol_code",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushSymbolCode(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getSymbolCode(); },
        }),
        symbol: createType({
            name: "symbol",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushSymbol(stringToSymbol(data)); },
            deserialize(buffer: SerialBuffer) { return symbolToString(buffer.getSymbol()); },
        }),
        asset: createType({
            name: "asset",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushAsset(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getAsset(); },
        }),
        checksum160: createType({
            name: "checksum160",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushUint8ArrayChecked(hexToUint8Array(data), 20); },
            deserialize(buffer: SerialBuffer) { return arrayToHex(buffer.getUint8Array(20)); },
        }),
        checksum256: createType({
            name: "checksum256",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushUint8ArrayChecked(hexToUint8Array(data), 32); },
            deserialize(buffer: SerialBuffer) { return arrayToHex(buffer.getUint8Array(32)); },
        }),
        checksum512: createType({
            name: "checksum512",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushUint8ArrayChecked(hexToUint8Array(data), 64); },
            deserialize(buffer: SerialBuffer) { return arrayToHex(buffer.getUint8Array(64)); },
        }),
        public_key: createType({
            name: "public_key",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushPublicKey(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getPublicKey(); },
        }),
        private_key: createType({
            name: "private_key",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushPrivateKey(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getPrivateKey(); },
        }),
        signature: createType({
            name: "signature",
            serialize(buffer: SerialBuffer, data: string) { buffer.pushSignature(data); },
            deserialize(buffer: SerialBuffer) { return buffer.getSignature(); },
        }),
    }));

    result.set("extended_asset", createType({
        name: "extended_asset",
        baseName: "",
        fields: [
            { name: "quantity", typeName: "asset", type: result.get("asset") },
            { name: "contract", typeName: "name", type: result.get("name") },
        ],
        serialize: serializeStruct,
        deserialize: deserializeStruct,
    }));

    return result;
} // createInitialTypes()

/** Get type from `types` */
export function getType(types: Map<string, Type>, name: string): Type {
    const type = types.get(name);
    if (type && type.aliasOfName) {
        return getType(types, type.aliasOfName);
    }
    if (type) {
        return type;
    }
    if (name.endsWith("[]")) {
        return createType({
            name,
            arrayOf: getType(types, name.substr(0, name.length - 2)),
            serialize: serializeArray,
            deserialize: deserializeArray,
        });
    }
    if (name.endsWith("?")) {
        return createType({
            name,
            optionalOf: getType(types, name.substr(0, name.length - 1)),
            serialize: serializeOptional,
            deserialize: deserializeOptional,
        });
    }
    if (name.endsWith("$")) {
        return createType({
            name,
            extensionOf: getType(types, name.substr(0, name.length - 1)),
            serialize: serializeExtension,
            deserialize: deserializeExtension,
        });
    }
    throw new Error("Unknown type: " + name);
}

/**
 * Get types from abi
 * @param initialTypes Set of types to build on.
 *     In most cases, it's best to fill this from a fresh call to `getTypesFromAbi()`.
 */
export function getTypesFromAbi(initialTypes: Map<string, Type>, abi: Abi) {
    const types = new Map(initialTypes);
    if (abi.types) {
        for (const { new_type_name, type } of abi.types) {
            types.set(new_type_name,
                createType({ name: new_type_name, aliasOfName: type }));
        }
    }
    if (abi.structs) {
        for (const { name, base, fields } of abi.structs) {
            types.set(name, createType({
                name,
                baseName: base,
                fields: fields.map(({ name: n, type }) => ({ name: n, typeName: type, type: null })),
                serialize: serializeStruct,
                deserialize: deserializeStruct,
            }));
        }
    }
    if (abi.variants) {
        for (const { name, types: t } of abi.variants) {
            types.set(name, createType({
                name,
                fields: t.map((s) => ({ name: s, typeName: s, type: null })),
                serialize: serializeVariant,
                deserialize: deserializeVariant,
            }));
        }
    }
    for (const [name, type] of types) {
        if (type.baseName) {
            type.base = getType(types, type.baseName);
        }
        for (const field of type.fields) {
            field.type = getType(types, field.typeName);
        }
    }
    return types;
} // getTypesFromAbi

/** TAPoS: Return transaction fields which reference `refBlock` and expire `expireSeconds` after `refBlock.timestamp` */
export function transactionHeader(refBlock: BlockTaposInfo, expireSeconds: number) {
    return {
        expiration: timePointSecToDate(dateToTimePointSec(refBlock.timestamp) + expireSeconds),
        ref_block_num: refBlock.block_num & 0xffff,
        ref_block_prefix: refBlock.ref_block_prefix,
    };
}

/** Convert action data to serialized form (hex) */
export function serializeActionData(contract: Contract, account: string, name: string, data: any,
                                    textEncoder: TextEncoder, textDecoder: TextDecoder): string {
    const action = contract.actions.get(name);
    if (!action) {
        throw new Error(`Unknown action ${name} in contract ${account}`);
    }
    const buffer = new SerialBuffer({ textEncoder, textDecoder });
    action.serialize(buffer, data);
    return arrayToHex(buffer.asUint8Array());
}

/** Return action in serialized form */
export function serializeAction(contract: Contract, account: string, name: string,
                                authorization: Authorization[], data: any, textEncoder: TextEncoder,
                                textDecoder: TextDecoder): SerializedAction {
    return {
        account,
        name,
        authorization,
        data: serializeActionData(contract, account, name, data, textEncoder, textDecoder),
    };
}

/** Deserialize action data. If `data` is a `string`, then it's assumed to be in hex. */
export function deserializeActionData(contract: Contract, account: string, name: string,
                                      data: string | Uint8Array | number[], textEncoder: TextEncoder,
                                      textDecoder: TextDecoder): any {
    const action = contract.actions.get(name);
    if (typeof data === "string") {
        data = hexToUint8Array(data);
    }
    if (!action) {
        throw new Error(`Unknown action ${name} in contract ${account}`);
    }
    const buffer = new SerialBuffer({ textDecoder, textEncoder });
    buffer.pushArray(data);
    return action.deserialize(buffer);
}

/** Deserialize action. If `data` is a `string`, then it's assumed to be in hex. */
export function deserializeAction(contract: Contract, account: string, name: string, authorization: Authorization[],
                                  data: string | Uint8Array | number[], textEncoder: TextEncoder,
                                  textDecoder: TextDecoder): Action {
    return {
        account,
        name,
        authorization,
        data: deserializeActionData(contract, account, name, data, textEncoder, textDecoder),
    };
}