/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the "Elastic License
 * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
 * Public License v 1"; you may not use this file except in compliance with, at
 * your election, the "Elastic License 2.0", the "GNU Affero General Public
 * License v3.0 only", or the "Server Side Public License, v 1".
 */

package org.elasticsearch.common.logging;

import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.impl.Log4jLogEvent;
import org.apache.logging.log4j.message.SimpleMessage;
import org.elasticsearch.test.ESTestCase;
import org.hamcrest.Matchers;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.StringReader;
import java.util.stream.Collectors;

import static org.hamcrest.Matchers.equalTo;

public class JsonThrowablePatternConverterTests extends ESTestCase {
    private static final String LINE_SEPARATOR = System.lineSeparator();
    private JsonThrowablePatternConverter converter = JsonThrowablePatternConverter.newInstance(null, null);

    public void testNoStacktrace() throws IOException {
        LogEvent event = Log4jLogEvent.newBuilder().build();
        String result = format(event);

        JsonLogLine jsonLogLine = JsonLogsStream.from(new BufferedReader(new StringReader(result)))
            .findFirst()
            .orElseThrow(() -> new AssertionError("no logs parsed"));

        assertThat(jsonLogLine.stacktrace(), Matchers.nullValue());
    }

    public void testStacktraceWithJson() throws IOException {
        String json = """
            {
              "terms": {
                "user": [
                  "u1",
                  "u2",
                  "u3"
                ],
                "boost": 1.0
              }
            }\
            """.lines().collect(Collectors.joining(LINE_SEPARATOR));
        Exception thrown = new Exception(json);
        LogEvent event = Log4jLogEvent.newBuilder().setMessage(new SimpleMessage("message")).setThrown(thrown).build();

        String result = format(event);

        // confirms exception is correctly parsed

        JsonLogLine jsonLogLine = JsonLogsStream.from(new BufferedReader(new StringReader(result)), JsonLogLine.ES_LOG_LINE)
            .findFirst()
            .orElseThrow(() -> new AssertionError("no logs parsed"));

        int jsonLength = json.split(LINE_SEPARATOR).length;
        int stacktraceLength = thrown.getStackTrace().length;
        assertThat(
            "stacktrace should formatted in multiple lines. JsonLogLine= " + jsonLogLine + " result= " + result,
            jsonLogLine.stacktrace().size(),
            equalTo(jsonLength + stacktraceLength)
        );
    }

    private String format(LogEvent event) {
        StringBuilder builder = new StringBuilder();
        converter.format(event, builder);
        String jsonStacktraceElement = builder.toString();

        return "{\"type\": \"console\", \"timestamp\": \"2019-01-03T16:30:53,058+0100\", \"level\": \"DEBUG\", "
            + "\"component\": \"o.e.a.s.TransportSearchAction\", \"cluster.name\": \"clustername\", \"node.name\": \"node-0\", "
            + "\"cluster.uuid\": \"OG5MkvOrR9azuClJhWvy6Q\", \"node.id\": \"VTShUqmcQG6SzeKY5nn7qA\",  \"message\": \"msg msg\" "
            + jsonStacktraceElement
            + "}";
    }
}