001/*
002 * SPDX-License-Identifier: Apache-2.0
003 *
004 * Copyright 2023-2026 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.common.io.resource;
019
020import java.io.IOException;
021
022/** {@link ReadableResource} which replaces text. */
023public class ReplacingResource extends DelegatingReadableResource {
024
025    // TODO Implement this more streaming-ly, without an intermediate String?
026
027    public ReplacingResource(ReadableResource delegate, String... replacements) throws IOException {
028        super(replace(delegate, replacements));
029    }
030
031    private static ReadableResource replace(ReadableResource delegate, String[] replacements)
032            throws IOException {
033        var template = delegate.charSource().read();
034        if (replacements.length % 2 != 0) {
035            throw new IllegalArgumentException("Not enough replacements");
036        }
037        for (int i = 0; i < replacements.length; i += 2) {
038            template = template.replace(replacements[i], replacements[i + 1]);
039        }
040        // NOT: return StringResource.of(template, delegate.mediaType());
041        var replaced = new MemoryResource(delegate.mediaType());
042        replaced.charSink().write(template);
043        return replaced;
044    }
045}