/*-
 * ========================LICENSE_START=================================
 * O-RAN-SC
 * %%
 * Copyright (C) 2023 Nordix Foundation
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ========================LICENSE_END===================================
 */

package org.oran.pmlog;

import java.io.ByteArrayInputStream;
import java.util.zip.GZIPInputStream;

import lombok.Getter;
import lombok.ToString;

import org.apache.kafka.common.header.Header;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@ToString
public class DataFromKafkaTopic {
    @Getter
    private final byte[] key;
    @Getter
    private final byte[] value;
    @Getter
    private String stringValue = null;
    private static final Logger logger = LoggerFactory.getLogger(DataFromKafkaTopic.class);

    public final Iterable<Header> headers;

    private static byte[] noBytes = new byte[0];

    public DataFromKafkaTopic(Iterable<Header> headers, byte[] key, byte[] value) {
        this.key = key == null ? noBytes : key;
        this.value = value == null ? noBytes : value;
        this.headers = headers;
    }

    public String valueAsString() {
        if (stringValue == null) {
            if (isZipped()) {
                stringValue = unzip(this.value);
            } else {
                stringValue = new String(this.value);
            }

        }
        return this.stringValue;
    }

    private String unzip(byte[] bytes) {
        try (final GZIPInputStream gzipInput = new GZIPInputStream(new ByteArrayInputStream(bytes))) {
            return new String(gzipInput.readAllBytes());
        } catch (Exception e) {
            logger.error("Could not unzip received info, reason: {}, typeId: {}", e.getMessage(),
                    getTypeIdFromHeaders());
            return "";
        }
    }

    public static final String ZIPPED_PROPERTY = "gzip";
    public static final String TYPE_ID_PROPERTY = "type-id";

    public boolean isZipped() {
        if (headers == null) {
            return false;
        }
        for (Header h : headers) {
            if (h.key().equals(ZIPPED_PROPERTY)) {
                return true;
            }
        }
        return false;
    }

    public String getTypeIdFromHeaders() {
        if (headers == null) {
            return "";
        }
        for (Header h : headers) {
            if (h.key().equals(TYPE_ID_PROPERTY)) {
                return new String(h.value());
            }
        }
        return "";
    }
}