decode.ts

export const decodeArg = (web3: Web3, hexString: string, solidityType: string, offsetInBytes: number, lengthInBytes: number): any => {
    if (lengthInBytes > 32) {
        throw new Error('Cannot decode types >32 bytes length');
    }
    const zxoffset = hexString.startsWith('0x') ? 2 : 0;
    const zeroedLength = 32 - lengthInBytes;
    return web3.eth.abi.decodeParameter(solidityType, '00'.repeat(zeroedLength) + hexString.slice(zxoffset + offsetInBytes * 2, zxoffset + (offsetInBytes + lengthInBytes) * 2));
};

export const decodePackedArgs = (web3: Web3, hexString: string, typeMetadatas: [string, number][]) => {
    const result = [];
    let offset = 0;
    for (let [name, size] of typeMetadatas) {
        result.push(decodeArg(web3, hexString, name, offset, size));
        offset += size;
    }
    return result;
}

const [price, tick, ...] = decodePackedArgs(web3, value,
            [['uint160', 20], ['int24', 3], ...]);