Intuitive DSL for Java

/*
 * This file is part of the Intuitive DSL project.
 * Copyright (c) 2026 DBA Labs - Switzerland. All rights reserved.
 *
 * This program is dual-licensed under a commercial license and the AGPLv3.
 * For commercial licensing, contact us at [email protected] or visit https://www.dbalabs.ch.
 *
 * AGPLv3 licensing:
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, version 3 (19 November 2007).
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <https://www.gnu.org/licenses/agpl-3.0.html>.
 */

package ch.dbalabs.intuitivedsl.parser;

import ch.dbalabs.intuitivedsl.exception.DslSyntaxException;
import ch.dbalabs.intuitivedsl.grammar.GrammarCompiler;
import ch.dbalabs.intuitivedsl.grammar.GroupNode;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

import java.util.List;

import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.assertThatThrownBy;
import static org.assertj.core.groups.Tuple.tuple;

class AlternativeAndGroupParsingTest {

    private GrammarCompiler compiler;
    private Lexer lexer;
    private AstNavigator navigator;

    @BeforeEach
    void setUp() {
        compiler = new GrammarCompiler();
        lexer = new Lexer();
        navigator = new AstNavigator();
    }

    @Test
    void shouldParseNestedRequiredAndOptionalGroupsAcrossBranches() {
        GroupNode ast = compiler.compile("DEPLOY { SERVICE service_name [ VERSION version ] | JOB job_name } ;");

        ParseResult serviceResult = navigator.parse(
                "DEPLOY SERVICE billing VERSION v2 ;",
                lexer.tokenize("DEPLOY SERVICE billing VERSION v2 ;"),
                ast,
                m -> List.of()
        );

        ParseResult jobResult = navigator.parse(
                "DEPLOY JOB cleanup ;",
                lexer.tokenize("DEPLOY JOB cleanup ;"),
                ast,
                m -> List.of()
        );

        assertThat(serviceResult.getParameters())
                .extracting(ParseResult.BoundParameter::name, ParseResult.BoundParameter::value)
                .containsExactly(tuple("service_name", "billing"), tuple("version", "v2"));

        assertThat(jobResult.getParameters())
                .extracting(ParseResult.BoundParameter::name, ParseResult.BoundParameter::value)
                .containsExactly(tuple("job_name", "cleanup"));
    }

    @Test
    void shouldRejectPartialOptionalGroupOnceStarted() {
        GroupNode ast = compiler.compile("CREATE USER username [ PASSWORD password ] ;");

        assertThatThrownBy(() -> navigator.parse(
                "CREATE USER john PASSWORD ;",
                lexer.tokenize("CREATE USER john PASSWORD ;"),
                ast,
                m -> List.of()
        )).isInstanceOf(DslSyntaxException.class)
          .satisfies(error -> {
              DslSyntaxException ex = (DslSyntaxException) error;
              assertThat(ex.getExpectedPossibilities()).contains("<password>");
          });
    }

    @Test
    void shouldRejectInputWhenNoRequiredAlternativeMatches() {
        GroupNode ast = compiler.compile("PROCESS { FILE file_path | DIRECTORY dir_path } ;");

        assertThatThrownBy(() -> navigator.parse(
                "PROCESS SOCKET conn1 ;",
                lexer.tokenize("PROCESS SOCKET conn1 ;"),
                ast,
                m -> List.of()
        )).isInstanceOf(DslSyntaxException.class)
          .satisfies(error -> {
              DslSyntaxException ex = (DslSyntaxException) error;
              assertThat(ex.getExpectedPossibilities()).containsAnyOf("FILE", "DIRECTORY");
          });
    }

    @Test
    void shouldParseDeeplyNestedAlternatives() {
        GroupNode ast = compiler.compile("ROUTE { HTTP { GET | POST } | MQ { PUBLISH | SUBSCRIBE } } target ;");

        ParseResult http = navigator.parse(
                "ROUTE HTTP GET api_users ;",
                lexer.tokenize("ROUTE HTTP GET api_users ;"),
                ast,
                m -> List.of()
        );

        ParseResult mq = navigator.parse(
                "ROUTE MQ SUBSCRIBE jobs ;",
                lexer.tokenize("ROUTE MQ SUBSCRIBE jobs ;"),
                ast,
                m -> List.of()
        );

        assertThat(http.hasKeyword("HTTP")).isTrue();
        assertThat(http.hasKeyword("GET")).isTrue();
        assertThat(http.getParameters()).extracting(ParseResult.BoundParameter::value).containsExactly("api_users");

        assertThat(mq.hasKeyword("MQ")).isTrue();
        assertThat(mq.hasKeyword("SUBSCRIBE")).isTrue();
        assertThat(mq.getParameters()).extracting(ParseResult.BoundParameter::value).containsExactly("jobs");
    }

    @Test
    void shouldTrackQuotedValueInsideNestedStructures() {
        GroupNode ast = compiler.compile("ROUTE { HTTP { GET | POST } | MQ { PUBLISH | SUBSCRIBE } } target [ WITH payload ] ;");

        ParseResult result = navigator.parse(
                "ROUTE MQ PUBLISH orders WITH 'priority=high ; retry=false' ;",
                lexer.tokenize("ROUTE MQ PUBLISH orders WITH 'priority=high ; retry=false' ;"),
                ast,
                m -> List.of()
        );

        assertThat(result.hasKeyword("MQ")).isTrue();
        assertThat(result.hasKeyword("PUBLISH")).isTrue();
        assertThat(result.getParameters())
                .extracting(ParseResult.BoundParameter::name, ParseResult.BoundParameter::value)
                .containsExactly(
                        tuple("target", "orders"),
                        tuple("payload", "priority=high ; retry=false")
                );
    }
}