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package com.mantledillusion.vaadin.cotton.viewpresenter;
import com.mantledillusion.injection.hura.core.Injector;
import com.mantledillusion.injection.hura.core.annotation.ValidatorUtils;
import com.mantledillusion.injection.hura.core.annotation.instruction.Construct;
import com.mantledillusion.injection.hura.core.annotation.lifecycle.Phase;
import com.mantledillusion.injection.hura.core.annotation.lifecycle.annotation.AnnotationProcessor;
import com.mantledillusion.vaadin.cotton.exception.http900.Http904IllegalAnnotationUseException;
import com.vaadin.flow.component.Component;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Parameter;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;
/**
* Basic interface for a {@link Presenter} that controls a {@link Presentable} after being hooked using @{@link Presented} on
* the {@link Presentable} implementation might @{@link Listen} to.
*
* Instances of implementations of {@link Presenter} will be instantiated automatically during injection for every
* {@link Presentable} implementation that requires controlling by an @{@link Presented} annotation on that view's {@link Class}.
*
* The {@link Presenter} will automatically be connected to the {@link Presentable} it belongs to, which will be passed
* to {@link #setView(Presentable)}.
*
* All {@link Method}s of {@link Presenter} implementations that are annotated with @{@link Listen} will receive
* events of specifiable types from {@link Component}s on the presented view that have been registered as active
* component to the {@link Presentable.TemporalActiveComponentRegistry}.
*
* @param
* The type of {@link Presentable} this {@link Presenter} can control.
*/
public interface Presenter {
class ListenValidator implements AnnotationProcessor {
@Construct
private ListenValidator() {}
@Override
public void process(Phase phase, Object bean, Listen annotationInstance, Method method,
Injector.TemporalInjectorCallback callback) {
Parameter[] parameters = method.getParameters();
if (Modifier.isStatic(method.getModifiers())) {
throw new Http904IllegalAnnotationUseException("The " + ValidatorUtils.getDescription(method)
+ " is annotated with @" + Listen.class.getSimpleName() + " but is declared static, which is "
+ "not allowed.");
} else if (!isValidPattern(annotationInstance.value())) {
throw new Http904IllegalAnnotationUseException("The " + ValidatorUtils.getDescription(method)
+ " is annotated with @" + Listen.class.getSimpleName() + " but declares the component id matcher '"
+ annotationInstance.value() + "', which is not a valid pattern.");
} else if (parameters.length > 1) {
throw new Http904IllegalAnnotationUseException("The " + ValidatorUtils.getDescription(method)
+ " is annotated with @" + Listen.class.getSimpleName() + " but declares " + parameters.length
+ " parameters; subscribing methods might only receive the event or nothing as argument.");
} else if (parameters.length == 0) {
if (annotationInstance.extensions().length == 0) {
throw new Http904IllegalAnnotationUseException("The " + ValidatorUtils.getDescription(method)
+ " is annotated with @" + Listen.class.getSimpleName() + " and declares no parameters, "
+ "but does also not declare at least one event extension class which is required when not "
+ "using a parameter.");
}
} else if (annotationInstance.extensions().length > 0) {
Class parameterType = parameters[0].getType();
for (Class extensionType: annotationInstance.extensions()) {
if (!parameterType.isAssignableFrom(extensionType)) {
throw new Http904IllegalAnnotationUseException("The " + ValidatorUtils.getDescription(method)
+ " is annotated with @" + Listen.class.getSimpleName() + " and declares a parameter "
+ "of the type " + parameterType.getSimpleName() + ", but also declares an extension "
+ "of the type " + extensionType.getSimpleName() + " which is not assignable.");
}
}
}
}
private boolean isValidPattern(String regex) {
try {
Pattern.compile(regex);
} catch (PatternSyntaxException e) {
return false;
}
return true;
}
}
/**
* Sets the {@link Presentable} this {@link Presenter} presents. Is called automatically on the correct
* {@link Presenter} a {@link Presentable} is @{@link Presented} by.
*
* The default implementation does nothing.
*
* @param view The view that is annotated with @{@link Presented} and that this {@link Presenter} instance presents;
* might not be null
*/
default void setView(V view) {}
}