/******************************************************************************* 
 * Copyright (c) 2008 Red Hat, Inc. 
 * Distributed under license by Red Hat, Inc. All rights reserved. 
 * This program is made available under the terms of the 
 * Eclipse Public License v1.0 which accompanies this distribution, 
 * and is available at http://www.eclipse.org/legal/epl-v10.html 
 * 
 * Contributors: 
 * Xavier Coulon - Initial API and implementation 
 ******************************************************************************/
package org.jboss.tools.ws.jaxrs.core.internal.metamodel.domain;

import static org.jboss.tools.ws.jaxrs.core.internal.metamodel.builder.JaxrsElementDelta.F_CONSUMED_MEDIATYPES_VALUE;
import static org.jboss.tools.ws.jaxrs.core.internal.metamodel.builder.JaxrsElementDelta.F_DEFAULT_VALUE_VALUE;
import static org.jboss.tools.ws.jaxrs.core.internal.metamodel.builder.JaxrsElementDelta.F_HTTP_METHOD_VALUE;
import static org.jboss.tools.ws.jaxrs.core.internal.metamodel.builder.JaxrsElementDelta.F_MATRIX_PARAM_VALUE;
import static org.jboss.tools.ws.jaxrs.core.internal.metamodel.builder.JaxrsElementDelta.F_METHOD_PARAMETERS;
import static org.jboss.tools.ws.jaxrs.core.internal.metamodel.builder.JaxrsElementDelta.F_PATH_VALUE;
import static org.jboss.tools.ws.jaxrs.core.internal.metamodel.builder.JaxrsElementDelta.F_PRODUCED_MEDIATYPES_VALUE;
import static org.jboss.tools.ws.jaxrs.core.internal.metamodel.builder.JaxrsElementDelta.F_QUERY_PARAM_VALUE;
import static org.jboss.tools.ws.jaxrs.core.jdt.EnumJaxrsClassname.DEFAULT_VALUE;
import static org.jboss.tools.ws.jaxrs.core.jdt.EnumJaxrsClassname.MATRIX_PARAM;
import static org.jboss.tools.ws.jaxrs.core.jdt.EnumJaxrsClassname.QUERY_PARAM;

import java.util.Arrays;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.IMethod;
import org.jboss.tools.ws.jaxrs.core.jdt.Annotation;
import org.jboss.tools.ws.jaxrs.core.jdt.JavaMethodParameter;
import org.jboss.tools.ws.jaxrs.core.metamodel.IJaxrsApplication;
import org.jboss.tools.ws.jaxrs.core.metamodel.IJaxrsEndpoint;
import org.jboss.tools.ws.jaxrs.core.metamodel.IJaxrsHttpMethod;
import org.jboss.tools.ws.jaxrs.core.metamodel.IJaxrsResourceMethod;

public class JaxrsEndpoint implements IJaxrsEndpoint {

	private final JaxrsMetamodel metamodel;

	private JaxrsHttpMethod httpMethod;

	private final LinkedList<JaxrsResourceMethod> resourceMethods;

	private IJaxrsApplication application = null;

	private String uriPathTemplate = null;

	private List<String> consumedMediaTypes = null;

	private List<String> producedMediaTypes = null;

	public JaxrsEndpoint(final JaxrsMetamodel metamodel, final JaxrsHttpMethod httpMethod,
			final JaxrsResourceMethod resourceMethod) {
		this(metamodel, httpMethod, new LinkedList<JaxrsResourceMethod>(Arrays.asList(resourceMethod)));
	}

	public JaxrsEndpoint(final JaxrsMetamodel metamodel, final JaxrsHttpMethod httpMethod,
			final LinkedList<JaxrsResourceMethod> resourceMethods) {
		this.metamodel = metamodel;
		this.application = (metamodel != null ? metamodel.getApplication() : null);
		this.httpMethod = httpMethod;
		this.resourceMethods = resourceMethods;
		refreshUriPathTemplate();
		refreshConsumedMediaTypes();
		refreshProducedMediaTypes();
	}

	/*
	 * (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {
		final IMethod javaMethod = resourceMethods.getLast().getJavaElement();
		return (httpMethod != null ? httpMethod.getHttpVerb() : null) + " " + uriPathTemplate + " | consumes:"
				+ consumedMediaTypes + " | produces=" + producedMediaTypes + " in method "
				+ javaMethod.getParent().getElementName() + "." + javaMethod.getElementName() + "(...)";
	}

	/*
	 * (non-Javadoc)
	 * @see java.lang.Object#hashCode()
	 */
	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((consumedMediaTypes == null) ? 0 : consumedMediaTypes.hashCode());
		result = prime * result + ((httpMethod == null) ? 0 : httpMethod.hashCode());
		result = prime * result + ((producedMediaTypes == null) ? 0 : producedMediaTypes.hashCode());
		result = prime * result + ((resourceMethods == null) ? 0 : resourceMethods.hashCode());
		result = prime * result + ((uriPathTemplate == null) ? 0 : uriPathTemplate.hashCode());
		return result;
	}

	/*
	 * (non-Javadoc)
	 * @see java.lang.Object#equals(java.lang.Object)
	 */
	@Override
	public boolean equals(Object obj) {
		if (this == obj) {
			return true;
		}
		if (obj == null) {
			return false;
		}
		if (getClass() != obj.getClass()) {
			return false;
		}
		JaxrsEndpoint other = (JaxrsEndpoint) obj;
		if (consumedMediaTypes == null) {
			if (other.consumedMediaTypes != null) {
				return false;
			}
		} else if (!consumedMediaTypes.equals(other.consumedMediaTypes)) {
			return false;
		}
		if (httpMethod == null) {
			if (other.httpMethod != null) {
				return false;
			}
		} else if (!httpMethod.equals(other.httpMethod)) {
			return false;
		}
		if (producedMediaTypes == null) {
			if (other.producedMediaTypes != null) {
				return false;
			}
		} else if (!producedMediaTypes.equals(other.producedMediaTypes)) {
			return false;
		}
		if (resourceMethods == null) {
			if (other.resourceMethods != null) {
				return false;
			}
		} else if (!resourceMethods.equals(other.resourceMethods)) {
			return false;
		}
		if (uriPathTemplate == null) {
			if (other.uriPathTemplate != null) {
				return false;
			}
		} else if (!uriPathTemplate.equals(other.uriPathTemplate)) {
			return false;
		}
		return true;
	}

	/**
	 * Triggers a refresh when changes occurred on the application element (whatever operation).
	 * 
	 * @return true if the endpoint is still valid, false otherwise (it should be removed from the metamodel)
	 */
	public boolean refresh(IJaxrsApplication application) {
		this.application = application;
		refreshUriPathTemplate();
		return true;
	}

	/**
	 * Triggers a refresh when changes occurred on one or more elements (HttpMethod and/or ResourcMethods) of the
	 * endpoint.
	 * 
	 * @return true if the endpoint is still valid, false otherwise (it should be removed from the metamodel)
	 */
	public boolean refresh(IJaxrsResourceMethod changedResourceMethod, int flags) {
		// check if the chain of resource methods still match
		/*
		 * if ((flags & F_ELEMENT_KIND) > 0 && changedResourceMethod.getKind() == EnumKind.SUBRESOURCE_LOCATOR) { return
		 * false; }
		 */

		if ((flags & F_HTTP_METHOD_VALUE) > 0) {
			refreshHttpMethod();
		}

		if ((flags & F_PATH_VALUE) > 0 || (flags & F_QUERY_PARAM_VALUE) > 0 || (flags & F_MATRIX_PARAM_VALUE) > 0 || (flags & F_DEFAULT_VALUE_VALUE) > 0
				|| (flags & F_METHOD_PARAMETERS) > 0) {
			refreshUriPathTemplate();
		}

		// look for mediatype capabilities at the method level, then fall back
		// at the type level, then "any" otherwise
		if ((flags & F_CONSUMED_MEDIATYPES_VALUE) > 0 || (flags & F_PRODUCED_MEDIATYPES_VALUE) > 0) {
			if ((flags & F_CONSUMED_MEDIATYPES_VALUE) > 0) {
				refreshConsumedMediaTypes();
			}
			if ((flags & F_PRODUCED_MEDIATYPES_VALUE) > 0) {
				refreshProducedMediaTypes();
			}
		}
		return true;
	}

	private void refreshHttpMethod() {
		final JaxrsResourceMethod resourceMethod = resourceMethods.getLast();
		final Annotation httpMethodAnnotation = resourceMethod.getHttpMethodAnnotation();
		if (httpMethodAnnotation != null) {
			this.httpMethod = metamodel.getHttpMethod(httpMethodAnnotation);
		}
	}

	private void refreshProducedMediaTypes() {
		final JaxrsResourceMethod resourceMethod = resourceMethods.getLast();
		final JaxrsResource resource = resourceMethod.getParentResource();
		if (resourceMethod.getProducedMediaTypes() != null) {
			this.producedMediaTypes = resourceMethod.getProducedMediaTypes();
		} else if (resourceMethod.getParentResource().getProducedMediaTypes() != null) {
			this.producedMediaTypes = resource.getProducedMediaTypes();
		} else {
			this.producedMediaTypes = Arrays.asList("*/*");
		}
	}

	private void refreshConsumedMediaTypes() {
		final JaxrsResourceMethod resourceMethod = resourceMethods.getLast();
		final JaxrsResource resource = resourceMethod.getParentResource();
		if (resourceMethod.getConsumedMediaTypes() != null) {
			this.consumedMediaTypes = resourceMethod.getConsumedMediaTypes();
		} else if (resourceMethod.getParentResource().getConsumedMediaTypes() != null) {
			this.consumedMediaTypes = resource.getConsumedMediaTypes();
		} else {
			this.consumedMediaTypes = Arrays.asList("*/*");
		}
	}

	private void refreshUriPathTemplate() {
		// compute the URI Path Template from the chain of Methods/Resources
		StringBuilder uriPathTemplateBuilder = new StringBuilder();
		if (application != null && application.getApplicationPath() != null) {
			uriPathTemplateBuilder.append(application.getApplicationPath());
		}
		for (JaxrsResourceMethod resourceMethod : resourceMethods) {
			if (resourceMethod.getParentResource().hasPathTemplate()) {
				uriPathTemplateBuilder.append("/").append(resourceMethod.getParentResource().getPathTemplate());
			}
			if (resourceMethod.hasPathTemplate()) {
				uriPathTemplateBuilder.append("/").append(resourceMethod.getPathTemplate());
			}
			refreshUriTemplateMatrixParams(uriPathTemplateBuilder, resourceMethod);
			refreshUriTemplateQueryParams(uriPathTemplateBuilder, resourceMethod);
		}
		this.uriPathTemplate = uriPathTemplateBuilder.toString();
		while (uriPathTemplate.indexOf("//") > -1) {
			this.uriPathTemplate = uriPathTemplate.replace("//", "/");
		}
	}

	private void refreshUriTemplateMatrixParams(StringBuilder uriPathTemplateBuilder, JaxrsResourceMethod resourceMethod) {
		final List<JavaMethodParameter> matrixParameters = resourceMethod
				.getJavaMethodParametersWithAnnotation(MATRIX_PARAM.qualifiedName);
		for(JavaMethodParameter matrixParameter : matrixParameters) {
			final Annotation matrixParamAnnotation = matrixParameter.getAnnotation(MATRIX_PARAM.qualifiedName);
			if(matrixParamAnnotation.getValue("value") != null) {
				uriPathTemplateBuilder.append(";").append(matrixParamAnnotation.getValue("value")).append("={")
				.append(matrixParameter.getTypeName()).append("}");
			}
		}
	}

	private void refreshUriTemplateQueryParams(StringBuilder uriPathTemplateBuilder, JaxrsResourceMethod resourceMethod) {
		final List<JavaMethodParameter> queryParameters = resourceMethod
				.getJavaMethodParametersWithAnnotation(QUERY_PARAM.qualifiedName);
		if (queryParameters.size() > 0) {
			uriPathTemplateBuilder.append('?');
			for (Iterator<JavaMethodParameter> iterator = queryParameters.iterator(); iterator.hasNext();) {
				JavaMethodParameter queryParam = iterator.next();
				final Annotation queryParamAnnotation = queryParam.getAnnotation(QUERY_PARAM.qualifiedName);
				final String paramName = queryParamAnnotation.getValue("value");
				if(paramName != null) {
					final String paramType = queryParam.getTypeName();
					uriPathTemplateBuilder.append(paramName).append("={");
					uriPathTemplateBuilder.append(paramName).append(":").append(paramType);
					final Annotation defaultValueAnnotation = queryParam.getAnnotation(DEFAULT_VALUE.qualifiedName);
					if (defaultValueAnnotation != null) {
						uriPathTemplateBuilder.append('=').append(defaultValueAnnotation.getValue("value"));
					}
					uriPathTemplateBuilder.append('}');
					// prepare for next query param item if there is more to process..
					if (iterator.hasNext()) {
						uriPathTemplateBuilder.append('&');
					}
				}
			}
		}
	}

	@Override
	public int compareTo(IJaxrsEndpoint other) {
		int uriPathTemplateComparison = this.uriPathTemplate.compareTo(other.getUriPathTemplate());
		if (uriPathTemplateComparison != 0) {
			return uriPathTemplateComparison;
		}
		return this.httpMethod.compareTo(other.getHttpMethod());
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.tools.ws.jaxrs.core.internal.metamodel.domain.IJaxrsEndpoint #getHttpMethod()
	 */
	@Override
	public IJaxrsHttpMethod getHttpMethod() {
		return httpMethod;
	}

	/**
	 * Convenient method to check if this endpoint uses this HttpMethod.
	 * 
	 * @return true if this endpoint's HttpMethod is the one given in parameter
	 */
	public boolean match(IJaxrsHttpMethod httpMethod) {
		return this.httpMethod.equals(httpMethod);
	}

	/** @return the resourceMethods */
	@Override
	public LinkedList<IJaxrsResourceMethod> getResourceMethods() {
		return new LinkedList<IJaxrsResourceMethod>(resourceMethods);
	}

	/**
	 * Convenient method to check if this endpoint uses this ResourceMethod.
	 * 
	 * @return true if this endpoint's ResourceMethod is the one given in parameter
	 */
	public boolean match(IJaxrsResourceMethod resourceMethod) {
		return this.resourceMethods.contains(resourceMethod);
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.tools.ws.jaxrs.core.internal.metamodel.domain.IJaxrsEndpoint #getUriPathTemplate()
	 */
	@Override
	public String getUriPathTemplate() {
		return uriPathTemplate;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.tools.ws.jaxrs.core.internal.metamodel.domain.IJaxrsEndpoint #getConsumedMediaTypes()
	 */
	@Override
	public List<String> getConsumedMediaTypes() {
		return consumedMediaTypes;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.tools.ws.jaxrs.core.internal.metamodel.domain.IJaxrsEndpoint #getProducedMediaTypes()
	 */
	@Override
	public List<String> getProducedMediaTypes() {
		return producedMediaTypes;
	}

	@Override
	public IJavaProject getJavaProject() {
		return this.metamodel.getJavaProject();
	}

	/**
	 * @return the problem level for this given endpoint. The returned problem level is the highest value
	 * from all the resource methods this endpoint is made of.
	 */
	@Override
	public int getProblemLevel() {
		int level = 0; // Severity NONE
		for (IJaxrsResourceMethod resourceMethod : getResourceMethods()) {
			level = Math.max(level, resourceMethod.getProblemLevel());
		}
		return level;
	}
}
