package io.quarkus.hibernate.validator.deployment;

import static io.quarkus.deployment.annotations.ExecutionTime.STATIC_INIT;

import java.lang.annotation.Repeatable;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.function.Predicate;
import java.util.regex.Pattern;

import javax.validation.ClockProvider;
import javax.validation.Constraint;
import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorFactory;
import javax.validation.MessageInterpolator;
import javax.validation.ParameterNameProvider;
import javax.validation.TraversableResolver;
import javax.validation.Valid;
import javax.validation.executable.ValidateOnExecution;
import javax.validation.valueextraction.ValueExtractor;

import org.hibernate.validator.internal.metadata.core.ConstraintHelper;
import org.hibernate.validator.messageinterpolation.AbstractMessageInterpolator;
import org.hibernate.validator.spi.messageinterpolation.LocaleResolver;
import org.hibernate.validator.spi.properties.GetterPropertySelectionStrategy;
import org.hibernate.validator.spi.scripting.ScriptEvaluatorFactory;
import org.jboss.jandex.AnnotationInstance;
import org.jboss.jandex.AnnotationTarget;
import org.jboss.jandex.ClassInfo;
import org.jboss.jandex.CompositeIndex;
import org.jboss.jandex.DotName;
import org.jboss.jandex.IndexView;
import org.jboss.jandex.MethodInfo;
import org.jboss.jandex.Type;

import io.quarkus.arc.deployment.AdditionalBeanBuildItem;
import io.quarkus.arc.deployment.AnnotationsTransformerBuildItem;
import io.quarkus.arc.deployment.BeanArchiveIndexBuildItem;
import io.quarkus.arc.deployment.BeanContainerListenerBuildItem;
import io.quarkus.arc.deployment.UnremovableBeanBuildItem;
import io.quarkus.arc.processor.BeanInfo;
import io.quarkus.arc.processor.DotNames;
import io.quarkus.deployment.Capabilities;
import io.quarkus.deployment.Capability;
import io.quarkus.deployment.Feature;
import io.quarkus.deployment.annotations.BuildProducer;
import io.quarkus.deployment.annotations.BuildStep;
import io.quarkus.deployment.annotations.Record;
import io.quarkus.deployment.builditem.CapabilityBuildItem;
import io.quarkus.deployment.builditem.CombinedIndexBuildItem;
import io.quarkus.deployment.builditem.FeatureBuildItem;
import io.quarkus.deployment.builditem.HotDeploymentWatchedFileBuildItem;
import io.quarkus.deployment.builditem.ShutdownContextBuildItem;
import io.quarkus.deployment.builditem.nativeimage.NativeImageConfigBuildItem;
import io.quarkus.deployment.builditem.nativeimage.ReflectiveFieldBuildItem;
import io.quarkus.deployment.builditem.nativeimage.ReflectiveMethodBuildItem;
import io.quarkus.deployment.logging.LogCleanupFilterBuildItem;
import io.quarkus.deployment.recording.RecorderContext;
import io.quarkus.hibernate.validator.runtime.HibernateValidatorBuildTimeConfig;
import io.quarkus.hibernate.validator.runtime.HibernateValidatorRecorder;
import io.quarkus.hibernate.validator.runtime.ValidatorProvider;
import io.quarkus.hibernate.validator.runtime.interceptor.MethodValidationInterceptor;
import io.quarkus.resteasy.common.spi.ResteasyDotNames;
import io.quarkus.resteasy.server.common.spi.AdditionalJaxRsResourceMethodAnnotationsBuildItem;
import io.quarkus.runtime.LocalesBuildTimeConfig;

class HibernateValidatorProcessor {

    private static final String META_INF_VALIDATION_XML = "META-INF/validation.xml";

    private static final DotName CONSTRAINT_VALIDATOR_FACTORY = DotName
            .createSimple(ConstraintValidatorFactory.class.getName());
    private static final DotName MESSAGE_INTERPOLATOR = DotName.createSimple(MessageInterpolator.class.getName());
    private static final DotName LOCALE_RESOLVER = DotName.createSimple(LocaleResolver.class.getName());

    private static final DotName TRAVERSABLE_RESOLVER = DotName.createSimple(TraversableResolver.class.getName());
    private static final DotName PARAMETER_NAME_PROVIDER = DotName.createSimple(ParameterNameProvider.class.getName());
    private static final DotName CLOCK_PROVIDER = DotName.createSimple(ClockProvider.class.getName());
    private static final DotName SCRIPT_EVALUATOR_FACTORY = DotName.createSimple(ScriptEvaluatorFactory.class.getName());
    private static final DotName GETTER_PROPERTY_SELECTION_STRATEGY = DotName
            .createSimple(GetterPropertySelectionStrategy.class.getName());

    private static final DotName CONSTRAINT_VALIDATOR = DotName.createSimple(ConstraintValidator.class.getName());
    private static final DotName VALUE_EXTRACTOR = DotName.createSimple(ValueExtractor.class.getName());

    private static final DotName VALIDATE_ON_EXECUTION = DotName.createSimple(ValidateOnExecution.class.getName());

    private static final DotName VALID = DotName.createSimple(Valid.class.getName());

    private static final DotName REPEATABLE = DotName.createSimple(Repeatable.class.getName());

    private static final Pattern BUILT_IN_CONSTRAINT_REPEATABLE_CONTAINER_PATTERN = Pattern.compile("\\$List$");

    @BuildStep
    CapabilityBuildItem capability() {
        return new CapabilityBuildItem(Capability.HIBERNATE_VALIDATOR);
    }

    @BuildStep
    HotDeploymentWatchedFileBuildItem configFile() {
        return new HotDeploymentWatchedFileBuildItem(META_INF_VALIDATION_XML);
    }

    @BuildStep
    LogCleanupFilterBuildItem logCleanup() {
        return new LogCleanupFilterBuildItem("org.hibernate.validator.internal.util.Version", "HV000001:");
    }

    @BuildStep
    void registerAdditionalBeans(BuildProducer<AdditionalBeanBuildItem> additionalBeans,
            BuildProducer<UnremovableBeanBuildItem> unremovableBean,
            Capabilities capabilities) {
        // The bean encapsulating the Validator and ValidatorFactory
        additionalBeans.produce(new AdditionalBeanBuildItem(ValidatorProvider.class));

        // The CDI interceptor which will validate the methods annotated with @MethodValidated
        additionalBeans.produce(new AdditionalBeanBuildItem(MethodValidationInterceptor.class));

        if (capabilities.isPresent(Capability.RESTEASY)) {
            // The CDI interceptor which will validate the methods annotated with @JaxrsEndPointValidated
            additionalBeans.produce(new AdditionalBeanBuildItem(
                    "io.quarkus.hibernate.validator.runtime.jaxrs.JaxrsEndPointValidationInterceptor"));
            additionalBeans.produce(new AdditionalBeanBuildItem(
                    "io.quarkus.hibernate.validator.runtime.jaxrs.ResteasyContextLocaleResolver"));
        }

        // Do not remove the Bean Validation beans
        unremovableBean.produce(new UnremovableBeanBuildItem(new Predicate<BeanInfo>() {
            @Override
            public boolean test(BeanInfo beanInfo) {
                return beanInfo.hasType(CONSTRAINT_VALIDATOR) || beanInfo.hasType(CONSTRAINT_VALIDATOR_FACTORY)
                        || beanInfo.hasType(MESSAGE_INTERPOLATOR) || beanInfo.hasType(TRAVERSABLE_RESOLVER)
                        || beanInfo.hasType(PARAMETER_NAME_PROVIDER) || beanInfo.hasType(CLOCK_PROVIDER)
                        || beanInfo.hasType(VALUE_EXTRACTOR) || beanInfo.hasType(SCRIPT_EVALUATOR_FACTORY)
                        || beanInfo.hasType(GETTER_PROPERTY_SELECTION_STRATEGY)
                        || beanInfo.hasType(LOCALE_RESOLVER);
            }
        }));
    }

    @BuildStep
    @Record(STATIC_INIT)
    public void build(HibernateValidatorRecorder recorder, RecorderContext recorderContext,
            BuildProducer<ReflectiveFieldBuildItem> reflectiveFields,
            BuildProducer<ReflectiveMethodBuildItem> reflectiveMethods,
            BuildProducer<AnnotationsTransformerBuildItem> annotationsTransformers,
            BeanArchiveIndexBuildItem beanArchiveIndexBuildItem,
            CombinedIndexBuildItem combinedIndexBuildItem,
            BuildProducer<FeatureBuildItem> feature,
            BuildProducer<BeanContainerListenerBuildItem> beanContainerListener,
            ShutdownContextBuildItem shutdownContext,
            List<AdditionalJaxRsResourceMethodAnnotationsBuildItem> additionalJaxRsResourceMethodAnnotations,
            Capabilities capabilities,
            LocalesBuildTimeConfig localesBuildTimeConfig,
            HibernateValidatorBuildTimeConfig hibernateValidatorBuildTimeConfig) throws Exception {

        feature.produce(new FeatureBuildItem(Feature.HIBERNATE_VALIDATOR));

        // we use both indexes to support both generated beans and jars that contain no CDI beans but only Validation annotations
        IndexView indexView = CompositeIndex.create(beanArchiveIndexBuildItem.getIndex(), combinedIndexBuildItem.getIndex());

        Set<DotName> consideredAnnotations = new HashSet<>();

        Set<String> builtinConstraints = ConstraintHelper.getBuiltinConstraints();

        // Collect the constraint annotations provided by Hibernate Validator and Bean Validation
        contributeBuiltinConstraints(builtinConstraints, consideredAnnotations);

        // Add the constraint annotations present in the application itself
        for (AnnotationInstance constraint : indexView.getAnnotations(DotName.createSimple(Constraint.class.getName()))) {
            consideredAnnotations.add(constraint.target().asClass().name());

            if (constraint.target().asClass().annotations().containsKey(REPEATABLE)) {
                for (AnnotationInstance repeatableConstraint : constraint.target().asClass().annotations()
                        .get(REPEATABLE)) {
                    consideredAnnotations.add(repeatableConstraint.value().asClass().name());
                }
            }
        }

        // Also consider elements that are marked with @Valid
        consideredAnnotations.add(VALID);

        // Also consider elements that are marked with @ValidateOnExecution
        consideredAnnotations.add(VALIDATE_ON_EXECUTION);

        Set<DotName> classNamesToBeValidated = new HashSet<>();
        Map<DotName, Set<SimpleMethodSignatureKey>> inheritedAnnotationsToBeValidated = new HashMap<>();
        Set<String> detectedBuiltinConstraints = new HashSet<>();

        for (DotName consideredAnnotation : consideredAnnotations) {
            Collection<AnnotationInstance> annotationInstances = indexView.getAnnotations(consideredAnnotation);

            if (annotationInstances.isEmpty()) {
                continue;
            }

            // we trim the repeatable container suffix if needed
            String builtinConstraintCandidate = BUILT_IN_CONSTRAINT_REPEATABLE_CONTAINER_PATTERN
                    .matcher(consideredAnnotation.toString()).replaceAll("");
            if (builtinConstraints.contains(builtinConstraintCandidate)) {
                detectedBuiltinConstraints.add(builtinConstraintCandidate);
            }

            for (AnnotationInstance annotation : annotationInstances) {
                if (annotation.target().kind() == AnnotationTarget.Kind.FIELD) {
                    contributeClass(classNamesToBeValidated, indexView, annotation.target().asField().declaringClass().name());
                    reflectiveFields.produce(new ReflectiveFieldBuildItem(annotation.target().asField()));
                    contributeClassMarkedForCascadingValidation(classNamesToBeValidated, indexView, consideredAnnotation,
                            annotation.target().asField().type());
                } else if (annotation.target().kind() == AnnotationTarget.Kind.METHOD) {
                    contributeClass(classNamesToBeValidated, indexView, annotation.target().asMethod().declaringClass().name());
                    // we need to register the method for reflection as it could be a getter
                    reflectiveMethods.produce(new ReflectiveMethodBuildItem(annotation.target().asMethod()));
                    contributeClassMarkedForCascadingValidation(classNamesToBeValidated, indexView, consideredAnnotation,
                            annotation.target().asMethod().returnType());
                    contributeMethodsWithInheritedValidation(inheritedAnnotationsToBeValidated, indexView,
                            annotation.target().asMethod());
                } else if (annotation.target().kind() == AnnotationTarget.Kind.METHOD_PARAMETER) {
                    contributeClass(classNamesToBeValidated, indexView,
                            annotation.target().asMethodParameter().method().declaringClass().name());
                    // a getter does not have parameters so it's a pure method: no need for reflection in this case
                    contributeClassMarkedForCascadingValidation(classNamesToBeValidated, indexView, consideredAnnotation,
                            // FIXME this won't work in the case of synthetic parameters
                            annotation.target().asMethodParameter().method().parameters()
                                    .get(annotation.target().asMethodParameter().position()));
                    contributeMethodsWithInheritedValidation(inheritedAnnotationsToBeValidated, indexView,
                            annotation.target().asMethodParameter().method());
                } else if (annotation.target().kind() == AnnotationTarget.Kind.CLASS) {
                    contributeClass(classNamesToBeValidated, indexView, annotation.target().asClass().name());
                    // no need for reflection in the case of a class level constraint
                }
            }
        }

        // JAX-RS methods are handled differently by the transformer so those need to be gathered here.
        // Note: The focus only on methods is basically an incomplete solution, since there could also be
        // class-level JAX-RS annotations but currently the transformer only looks at methods.
        Map<DotName, Set<SimpleMethodSignatureKey>> jaxRsMethods = gatherJaxRsMethods(additionalJaxRsResourceMethodAnnotations,
                indexView);

        // Add the annotations transformer to add @MethodValidated annotations on the methods requiring validation

        annotationsTransformers
                .produce(new AnnotationsTransformerBuildItem(
                        new MethodValidatedAnnotationsTransformer(consideredAnnotations,
                                jaxRsMethods,
                                inheritedAnnotationsToBeValidated)));

        Set<Class<?>> classesToBeValidated = new HashSet<>();
        for (DotName className : classNamesToBeValidated) {
            classesToBeValidated.add(recorderContext.classProxy(className.toString()));
        }

        beanContainerListener
                .produce(new BeanContainerListenerBuildItem(
                        recorder.initializeValidatorFactory(classesToBeValidated, detectedBuiltinConstraints,
                                hasXmlConfiguration(),
                                capabilities.isPresent(Capability.HIBERNATE_ORM),
                                shutdownContext,
                                localesBuildTimeConfig,
                                hibernateValidatorBuildTimeConfig)));
    }

    @BuildStep
    NativeImageConfigBuildItem nativeImageConfig() {
        return NativeImageConfigBuildItem.builder()
                .addResourceBundle(AbstractMessageInterpolator.DEFAULT_VALIDATION_MESSAGES)
                .addResourceBundle(AbstractMessageInterpolator.USER_VALIDATION_MESSAGES)
                .addResourceBundle(AbstractMessageInterpolator.CONTRIBUTOR_VALIDATION_MESSAGES)
                .build();
    }

    private static void contributeBuiltinConstraints(Set<String> builtinConstraints,
            Set<DotName> consideredAnnotationsCollector) {
        for (String builtinConstraint : builtinConstraints) {
            consideredAnnotationsCollector.add(DotName.createSimple(builtinConstraint));

            // for all built-in constraints, we follow a strict convention for repeatable annotations,
            // they are all inner classes called List
            // while not all our built-in constraints are repeatable, let's avoid loading the class to check
            consideredAnnotationsCollector.add(DotName.createSimple(builtinConstraint + "$List"));
        }
    }

    private static void contributeClass(Set<DotName> classNamesCollector, IndexView indexView, DotName className) {
        classNamesCollector.add(className);

        if (DotNames.OBJECT.equals(className)) {
            return;
        }

        for (ClassInfo subclass : indexView.getAllKnownSubclasses(className)) {
            if (Modifier.isAbstract(subclass.flags())) {
                // we can avoid adding the abstract classes here: either they are parent classes
                // and they will be dealt with by Hibernate Validator or they are child classes
                // without any proper implementation and we can ignore them.
                continue;
            }
            classNamesCollector.add(subclass.name());
        }
        for (ClassInfo implementor : indexView.getAllKnownImplementors(className)) {
            if (Modifier.isAbstract(implementor.flags())) {
                // we can avoid adding the abstract classes here: either they are parent classes
                // and they will be dealt with by Hibernate Validator or they are child classes
                // without any proper implementation and we can ignore them.
                continue;
            }
            classNamesCollector.add(implementor.name());
        }
    }

    private static void contributeClassMarkedForCascadingValidation(Set<DotName> classNamesCollector,
            IndexView indexView, DotName consideredAnnotation, Type type) {
        if (VALID != consideredAnnotation) {
            return;
        }

        DotName className = getClassName(type);
        if (className != null) {
            contributeClass(classNamesCollector, indexView, className);
        }
    }

    private static void contributeMethodsWithInheritedValidation(
            Map<DotName, Set<SimpleMethodSignatureKey>> inheritedAnnotationsToBeValidated,
            IndexView indexView, MethodInfo method) {
        ClassInfo clazz = method.declaringClass();
        if (Modifier.isInterface(clazz.flags())) {
            // Remember annotated interface methods that must be validated
            inheritedAnnotationsToBeValidated.computeIfAbsent(clazz.name(), k -> new HashSet<>())
                    .add(new SimpleMethodSignatureKey(method));
        }
    }

    private static Map<DotName, Set<SimpleMethodSignatureKey>> gatherJaxRsMethods(
            List<AdditionalJaxRsResourceMethodAnnotationsBuildItem> additionalJaxRsResourceMethodAnnotations,
            IndexView indexView) {
        Map<DotName, Set<SimpleMethodSignatureKey>> jaxRsMethods = new HashMap<>();

        Collection<DotName> jaxRsMethodDefiningAnnotations = new ArrayList<>(
                ResteasyDotNames.JAXRS_METHOD_ANNOTATIONS.size() + additionalJaxRsResourceMethodAnnotations.size());
        jaxRsMethodDefiningAnnotations.addAll(ResteasyDotNames.JAXRS_METHOD_ANNOTATIONS);
        for (AdditionalJaxRsResourceMethodAnnotationsBuildItem additionalJaxRsResourceMethodAnnotation : additionalJaxRsResourceMethodAnnotations) {
            jaxRsMethodDefiningAnnotations.addAll(additionalJaxRsResourceMethodAnnotation.getAnnotationClasses());
        }

        for (DotName jaxRsAnnotation : jaxRsMethodDefiningAnnotations) {
            Collection<AnnotationInstance> annotationInstances = indexView.getAnnotations(jaxRsAnnotation);

            if (annotationInstances.isEmpty()) {
                continue;
            }

            for (AnnotationInstance annotation : annotationInstances) {
                if (annotation.target().kind() == AnnotationTarget.Kind.METHOD) {
                    MethodInfo method = annotation.target().asMethod();
                    jaxRsMethods.computeIfAbsent(method.declaringClass().name(), k -> new HashSet<>())
                            .add(new SimpleMethodSignatureKey(method));
                }
            }
        }
        return jaxRsMethods;
    }

    private static DotName getClassName(Type type) {
        switch (type.kind()) {
            case CLASS:
            case PARAMETERIZED_TYPE:
                return type.name();
            case ARRAY:
                return getClassName(type.asArrayType().component());
            default:
                return null;
        }
    }

    private static boolean hasXmlConfiguration() {
        return Thread.currentThread().getContextClassLoader().getResource(META_INF_VALIDATION_XML) != null;
    }

}
