@aeternity/aepp-calldata/src/Serializers/VariantSerializer.js

Aeternity data serialization library

import RLP from 'rlp'
import FateTag from '../FateTag.js'
import FateTuple from '../types/FateTuple.js'
import FateVariant from '../types/FateVariant.js'
import {FateTypeTuple} from '../FateTypes.js'
import BaseSerializer from './BaseSerializer.js'

class VariantSerializer extends BaseSerializer {
    serialize(variant) {
        const valueTuple = new FateTuple(variant.valueTypes, variant.value)

        return [
            FateTag.VARIANT,
            ...RLP.encode(new Uint8Array(variant.arities)),
            variant.tag,
            ...this.globalSerializer.serialize(valueTuple)
        ]
    }

    deserializeStream(stream, typeInfo) {
        const buffer = new Uint8Array(stream)
        const decoded = RLP.decode(buffer.slice(1), true)
        const arities = [...decoded.data]
        const tag = decoded.remainder[0]
        const data = decoded.remainder.slice(1)
        let variants = []
        let valueType

        if (typeof typeInfo !== 'undefined' && typeof typeInfo.variants !== 'undefined') {
            variants = typeInfo.variants
            valueType = FateTypeTuple(Object.values(variants[tag])[0])
        }

        const [els, rest] = this.globalSerializer.deserializeStream(data, valueType)

        return [
            new FateVariant(arities, tag, els.items, els.valueTypes, variants),
            rest
        ]
    }
}

export default VariantSerializer