adapter.ts

import type Address from '../../ad4m/Address'
import type Expression from '../../ad4m/Expression'
import type { ExpressionAdapter, PublicSharing } from '../../ad4m/Language'
import type LanguageContext from '../../ad4m/LanguageContext'
import type { IPFSNode } from '../../ad4m/LanguageContext'
import { IpfsPutAdapter } from './putAdapter'

const _appendBuffer = (buffer1, buffer2) => {
    const tmp = new Uint8Array(buffer1.byteLength + buffer2.byteLength);
    tmp.set(new Uint8Array(buffer1), 0);
    tmp.set(new Uint8Array(buffer2), buffer1.byteLength);
    return tmp.buffer;
};

const uint8ArrayConcat = (chunks) => {
    return chunks.reduce(_appendBuffer)
}



export default class Adapter implements ExpressionAdapter {
    #IPFS: IPFSNode

    putAdapter: PublicSharing

    constructor(context: LanguageContext) {
        this.#IPFS = context.IPFS
        this.putAdapter = new IpfsPutAdapter(context)
    }

    async get(address: Address): Promise<void | Expression> {
        const cid = address.toString()

        const chunks = []
        // @ts-ignore
        for await (const chunk of this.#IPFS.cat(cid)) {
            chunks.push(chunk)
        }

        const fileString = uint8ArrayConcat(chunks).toString();
        const fileJson = JSON.parse(fileString)
        return fileJson

    }
}