package io.trygvis.container.compiler;

import io.trygvis.container.log.Log;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.processing.Completion;
import javax.annotation.processing.ProcessingEnvironment;
import javax.annotation.processing.Processor;
import javax.annotation.processing.RoundEnvironment;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.Element;
import javax.lang.model.element.ExecutableElement;
import javax.lang.model.element.TypeElement;
import javax.lang.model.util.Elements;
import javax.lang.model.util.Types;
import java.util.HashSet;
import java.util.Set;

import static java.util.Arrays.asList;
import static java.util.Collections.emptyList;
import static java.util.Collections.emptySet;

public class MyProcessor implements Processor {

    private ProcessingEnvironment processingEnv;
    private Elements elements;
    private Types types;

    @Override
    public Set<String> getSupportedOptions() {
        return emptySet();
    }

    @Override
    public SourceVersion getSupportedSourceVersion() {
        return SourceVersion.RELEASE_5;
    }

    @Override
    public void init(ProcessingEnvironment processingEnv) {
        this.processingEnv = processingEnv;
        elements = processingEnv.getElementUtils();
        types = processingEnv.getTypeUtils();
    }

    @Override
    public Iterable<? extends Completion> getCompletions(Element element, AnnotationMirror annotation, ExecutableElement member, String userText) {
        return emptyList();
    }

    @Override
    public Set<String> getSupportedAnnotationTypes() {
        return new HashSet<>(asList(Transactional.class.getName(), Log.class.getName()));
    }

    @Override
    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
        Set<? extends Element> transactional = roundEnv.getElementsAnnotatedWith(Transactional.class);

        TypeElement tx = elements.getTypeElement(Transactional.class.getCanonicalName());
        TypeElement log = elements.getTypeElement(Transactional.class.getCanonicalName());

        for (Element element : transactional) {
            try {
                System.out.println("Processing: " + element);
                for (AnnotationMirror annotationMirror : element.getAnnotationMirrors()) {

                    if (types.isSameType(tx.asType(), annotationMirror.getAnnotationType())) {
                        new TransactionalHandler(processingEnv).processTransactional((TypeElement) element);
                    }
                    if (types.isSameType(log.asType(), annotationMirror.getAnnotationType())) {
                        new LogHandler(processingEnv).processLog((TypeElement) element);
                    }
                }
            } catch (RuntimeException e) {
                throw e;
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
        return true;
    }
}