package io.trygvis.rules.engine;

import org.drools.core.audit.WorkingMemoryConsoleLogger;
import org.kie.api.KieServices;
import org.kie.api.event.rule.AgendaEventListener;
import org.kie.api.event.rule.RuleRuntimeEventListener;
import org.kie.api.io.Resource;
import org.kie.api.runtime.KieContainer;
import org.kie.api.runtime.KieSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.Closeable;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class Engine implements Closeable {
    private final Logger logger = LoggerFactory.getLogger(getClass());

    public final DbIo io;
    public final KieSession session;

    public Engine(String name, File database, File output, String[] agendaGroups, File[] modules) throws IOException {
        logger.info("Getting KieServices");

        var services = KieServices.Factory.get();

        logger.info("services = {}", services);

        var kieRepository = services.getRepository();
        logger.info("kieRepository.getDefaultReleaseId() = {}", kieRepository.getDefaultReleaseId());

        KieContainer container;
        if (modules != null && modules.length > 0) {
            List<Resource> resources = new ArrayList<>();
            for (File path : modules) {
                if (!path.exists()) {
                    logger.warn("Module path does not exist: {}", path.getAbsolutePath());
                    continue;
                }

                logger.info("New KieBuilder: {}, file={}, directory={}", path, path.isFile(), path.isDirectory());

                var resource = services.getResources().newFileSystemResource(path);
                logger.info("resource.getResourceType() = {}", resource.getResourceType());
                resources.add(resource);
            }

            var module = kieRepository.addKieModule(resources.get(0), resources.subList(1, resources.size()).toArray(new Resource[0]));
            logger.info("module.getReleaseId() = {}", module.getReleaseId());
            var rId = module.getReleaseId();

            logger.info("Creating classpath container, releaseId=" + rId);
            container = services.newKieContainer(rId);
        } else {
            container = services.getKieClasspathContainer();
        }

        logger.info("Creating KieBase \"{}\"", name);
        logger.info("Available kie base names: {}", container.getKieBaseNames());
        var kieBase = container.getKieBase(name);

        session = container.newKieSession(name);

        var l = new WorkingMemoryConsoleLogger(session);
        session.addEventListener((AgendaEventListener) l);
        session.addEventListener((RuleRuntimeEventListener) l);

        session.setGlobal("te", new JinjavaTemplateEngine(output));

        logger.info("Loading data");
        io = new DbIo(container, kieBase);
        var objects = io.load(database);
        logger.info("Loaded {} objects", objects.size());

        for (var object : objects) {
            logger.info("object = " + object);
            session.insert(object);
        }

        for (var agendaGroup : agendaGroups) {
            logger.info("Setting agenda: " + agendaGroup);
            session.getAgenda().getAgendaGroup(agendaGroup).setFocus();
            session.fireAllRules();
        }
    }

    @Override
    public void close() {
        session.dispose();
    }
}