/*
 * 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 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 or the Server
 * Side Public License, v 1.
 */

package org.elasticsearch.script.mustache;

import org.elasticsearch.common.bytes.BytesReference;
import org.elasticsearch.common.xcontent.XContentHelper;
import org.elasticsearch.script.ScriptType;
import org.elasticsearch.test.AbstractXContentTestCase;
import org.elasticsearch.xcontent.ToXContent;
import org.elasticsearch.xcontent.XContentBuilder;
import org.elasticsearch.xcontent.XContentFactory;
import org.elasticsearch.xcontent.XContentParseException;
import org.elasticsearch.xcontent.XContentParser;
import org.elasticsearch.xcontent.XContentType;
import org.elasticsearch.xcontent.json.JsonXContent;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;

import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertToXContentEquivalent;
import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.hasEntry;
import static org.hamcrest.Matchers.nullValue;

public class SearchTemplateRequestXContentTests extends AbstractXContentTestCase<SearchTemplateRequest> {

    @Override
    public SearchTemplateRequest createTestInstance() {
        return SearchTemplateRequestTests.createRandomRequest();
    }

    @Override
    protected SearchTemplateRequest doParseInstance(XContentParser parser) throws IOException {
        return SearchTemplateRequest.fromXContent(parser);
    }

    /**
     * Note that when checking equality for xContent parsing, we omit two parts of the request:
     * - The 'simulate' option, since this parameter is not included in the
     *   request's xContent (it's instead used to determine the request endpoint).
     * - The random SearchRequest, since this component only affects the request
     *   parameters and also isn't captured in the request's xContent.
     */
    @Override
    protected void assertEqualInstances(SearchTemplateRequest expectedInstance, SearchTemplateRequest newInstance) {
        assertTrue(
            expectedInstance.isExplain() == newInstance.isExplain()
                && expectedInstance.isProfile() == newInstance.isProfile()
                && expectedInstance.getScriptType() == newInstance.getScriptType()
                && Objects.equals(expectedInstance.getScript(), newInstance.getScript())
                && Objects.equals(expectedInstance.getScriptParams(), newInstance.getScriptParams())
        );
    }

    @Override
    protected boolean supportsUnknownFields() {
        return false;
    }

    public void testToXContentWithInlineTemplate() throws IOException {
        SearchTemplateRequest request = new SearchTemplateRequest();

        request.setScriptType(ScriptType.INLINE);
        request.setScript("""
            {"query": { "match" : { "{{my_field}}" : "{{my_value}}" } } }""");
        request.setProfile(true);

        Map<String, Object> scriptParams = new HashMap<>();
        scriptParams.put("my_field", "foo");
        scriptParams.put("my_value", "bar");
        request.setScriptParams(scriptParams);

        XContentType contentType = randomFrom(XContentType.values());
        XContentBuilder expectedRequest = XContentFactory.contentBuilder(contentType)
            .startObject()
            .field("source", """
                {"query": { "match" : { "{{my_field}}" : "{{my_value}}" } } }""")
            .startObject("params")
            .field("my_field", "foo")
            .field("my_value", "bar")
            .endObject()
            .field("explain", false)
            .field("profile", true)
            .endObject();

        XContentBuilder actualRequest = XContentFactory.contentBuilder(contentType);
        request.toXContent(actualRequest, ToXContent.EMPTY_PARAMS);

        assertToXContentEquivalent(BytesReference.bytes(expectedRequest), BytesReference.bytes(actualRequest), contentType);
    }

    public void testToXContentWithStoredTemplate() throws IOException {
        SearchTemplateRequest request = new SearchTemplateRequest();

        request.setScriptType(ScriptType.STORED);
        request.setScript("match_template");
        request.setExplain(true);

        Map<String, Object> params = new HashMap<>();
        params.put("my_field", "foo");
        params.put("my_value", "bar");
        request.setScriptParams(params);

        XContentType contentType = randomFrom(XContentType.values());
        XContentBuilder expectedRequest = XContentFactory.contentBuilder(contentType)
            .startObject()
            .field("id", "match_template")
            .startObject("params")
            .field("my_field", "foo")
            .field("my_value", "bar")
            .endObject()
            .field("explain", true)
            .field("profile", false)
            .endObject();

        XContentBuilder actualRequest = XContentFactory.contentBuilder(contentType);
        request.toXContent(actualRequest, ToXContent.EMPTY_PARAMS);

        assertToXContentEquivalent(BytesReference.bytes(expectedRequest), BytesReference.bytes(actualRequest), contentType);
    }

    public void testFromXContentWithEmbeddedTemplate() throws Exception {
        String source = """
            {
              'source' : {
                'query': {
                  'terms': {
                    'status': [
                      '{{#status}}',
                      '{{.}}',
                      '{{/status}}'
                    ]
                  }
                }
              }}""";

        SearchTemplateRequest request = SearchTemplateRequest.fromXContent(newParser(source));
        assertThat(request.getScript(), equalTo("""
            {"query":{"terms":{"status":["{{#status}}","{{.}}","{{/status}}"]}}}"""));
        assertThat(request.getScriptType(), equalTo(ScriptType.INLINE));
        assertThat(request.getScriptParams(), nullValue());
    }

    public void testFromXContentWithEmbeddedTemplateAndParams() throws Exception {
        String source = """
            {
                'source' : {
                  'query': { 'match' : { '{{my_field}}' : '{{my_value}}' } },
                  'size' : '{{my_size}}'
                },
                'params' : {
                    'my_field' : 'foo',
                    'my_value' : 'bar',
                    'my_size' : 5
                }
            }""";

        SearchTemplateRequest request = SearchTemplateRequest.fromXContent(newParser(source));
        assertThat(request.getScript(), equalTo(XContentHelper.stripWhitespace("""
            {
              "query": {
                "match": {
                  "{{my_field}}": "{{my_value}}"
                }
              },
              "size": "{{my_size}}"
            }""")));
        assertThat(request.getScriptType(), equalTo(ScriptType.INLINE));
        assertThat(request.getScriptParams().size(), equalTo(3));
        assertThat(request.getScriptParams(), hasEntry("my_field", "foo"));
        assertThat(request.getScriptParams(), hasEntry("my_value", "bar"));
        assertThat(request.getScriptParams(), hasEntry("my_size", 5));
    }

    public void testFromXContentWithMalformedRequest() {
        // Unclosed template id
        expectThrows(XContentParseException.class, () -> SearchTemplateRequest.fromXContent(newParser("{'id' : 'another_temp }")));
    }

    /**
     * Creates a {@link XContentParser} with the given String while replacing single quote to double quotes.
     */
    private XContentParser newParser(String s) throws IOException {
        assertNotNull(s);
        return createParser(JsonXContent.jsonXContent, s.replace("'", "\""));
    }
}
