001/*
002 * SPDX-License-Identifier: Apache-2.0
003 *
004 * Copyright 2025-2026 The Enola <https://enola.dev> Authors
005 *
006 * Licensed under the Apache License, Version 2.0 (the "License");
007 * you may not use this file except in compliance with the License.
008 * You may obtain a copy of the License at
009 *
010 *     https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package dev.enola.cas;
019
020import com.google.common.io.ByteSource;
021
022import io.ipfs.api.AddArgs;
023import io.ipfs.api.IPFS;
024import io.ipfs.api.NamedStreamable;
025import io.ipfs.cid.Cid;
026
027import org.slf4j.Logger;
028import org.slf4j.LoggerFactory;
029
030import java.io.IOException;
031
032// https://docs.ipfs.tech/reference/kubo/rpc/
033/** <a href="https://ipfs.tech/">IPFS</a> Kubo RPC API client. */
034public class IPFSBlobStore implements BlobStore {
035    private final Logger LOG = LoggerFactory.getLogger(getClass());
036
037    // TODO: Support IPLD <=> Thing API bridge; see https://github.com/enola-dev/enola/issues/777.
038
039    private final IPFS ipfs;
040
041    public IPFSBlobStore(IPFS ipfs) {
042        this.ipfs = ipfs;
043        try {
044            LOG.info("{}", ipfs.version());
045            LOG.info("IPFS {}", ipfs.version);
046        } catch (IOException e) {
047            LOG.error("Failed to retrieve IPFS version", e);
048        }
049    }
050
051    @Override
052    public ByteSource load(Cid cid) throws IOException {
053        return ByteSource.wrap(ipfs.cat(cid));
054    }
055
056    public ByteSource load(Cid cid, String subPath) throws IOException {
057        return ByteSource.wrap(ipfs.cat(cid, subPath));
058    }
059
060    @Override
061    public Cid store(ByteSource source) throws IOException {
062        try (var is = source.openStream()) {
063            var namedStreamable = new NamedStreamable.InputStreamWrapper(is);
064            // TODO .setHash("blake3") https://github.com/multiformats/java-multihash/issues/49
065            var args = AddArgs.Builder.newInstance().setCidVersion(1).build();
066            var merkleNode = ipfs.add(namedStreamable, args);
067            return Cid.build(1, Cid.Codec.Raw, merkleNode.get(0).hash);
068        }
069    }
070
071    // TODO Cid store(Tree of relative directories & files...)
072}