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package jdk.javadoc.internal.doclets.toolkit.util;

import java.util.*;

import javax.lang.model.element.ExecutableElement;
import javax.lang.model.element.TypeElement;
import javax.lang.model.type.TypeMirror;

import jdk.javadoc.internal.doclets.toolkit.Configuration;

For a given class method, build an array of interface methods which it
implements.
 
This is NOT part of any supported API.
 If you write code that depends on this, you do so at your own risk.
 This code and its internal interfaces are subject to change or
 deletion without notice.
Author:
Atul M Dambalkar/**
 * For a given class method, build an array of interface methods which it
 * implements.
 *
 *  <p><b>This is NOT part of any supported API.
 *  If you write code that depends on this, you do so at your own risk.
 *  This code and its internal interfaces are subject to change or
 *  deletion without notice.</b>
 *
 * @author Atul M Dambalkar
 */
public class ImplementedMethods {

    private final Map<ExecutableElement, TypeMirror> interfaces = new HashMap<>();
    private final List<ExecutableElement> methlist = new ArrayList<>();
    private final Utils utils;
    private final TypeElement typeElement;
    private final ExecutableElement method;

    public ImplementedMethods(ExecutableElement method, Configuration configuration) {
        this.method = method;
        this.utils = configuration.utils;
        typeElement = utils.getEnclosingTypeElement(method);
    }

    
Return the array of interface methods which the method passed in the
constructor is implementing. The search/build order is as follows:
1. Search in all the immediate interfaces which this method's class is
   implementing. Do it recursively for the superinterfaces as well.
2. Traverse all the superclasses and search recursively in the
   interfaces which those superclasses implement.

Returns:
SortedSet of implemented methods./**
     * Return the array of interface methods which the method passed in the
     * constructor is implementing. The search/build order is as follows:
     * <pre>
     * 1. Search in all the immediate interfaces which this method's class is
     *    implementing. Do it recursively for the superinterfaces as well.
     * 2. Traverse all the superclasses and search recursively in the
     *    interfaces which those superclasses implement.
     *</pre>
     *
     * @return SortedSet<ExecutableElement> of implemented methods.
     */
    public List<ExecutableElement> build() {
        buildImplementedMethodList();
        return methlist;
    }

    public TypeMirror getMethodHolder(ExecutableElement ee) {
        return interfaces.get(ee);
    }

    
Search for the method in the array of interfaces. If found check if it is
overridden by any other subinterface method which this class
implements. If it is not overidden, add it in the method list.
Do this recursively for all the extended interfaces for each interface
from the array passed.
/**
     * Search for the method in the array of interfaces. If found check if it is
     * overridden by any other subinterface method which this class
     * implements. If it is not overidden, add it in the method list.
     * Do this recursively for all the extended interfaces for each interface
     * from the array passed.
     */
    private void buildImplementedMethodList() {
        Set<TypeMirror> intfacs = utils.getAllInterfaces(typeElement);
        for (TypeMirror interfaceType : intfacs) {
            ExecutableElement found = utils.findMethod(utils.asTypeElement(interfaceType), method);
            if (found != null) {
                removeOverriddenMethod(found);
                if (!overridingMethodFound(found)) {
                    methlist.add(found);
                    interfaces.put(found, interfaceType);
                }
            }
        }
    }

    
Search in the method list and check if it contains a method which
is overridden by the method as parameter.  If found, remove the
overridden method from the method list.
Params:
method – Is this method overriding a method in the method list./**
     * Search in the method list and check if it contains a method which
     * is overridden by the method as parameter.  If found, remove the
     * overridden method from the method list.
     *
     * @param method Is this method overriding a method in the method list.
     */
    private void removeOverriddenMethod(ExecutableElement method) {
        TypeElement overriddenClass = utils.overriddenClass(method);
        if (overriddenClass != null) {
            for (int i = 0; i < methlist.size(); i++) {
                TypeElement te = utils.getEnclosingTypeElement(methlist.get(i));
                if (te == overriddenClass || utils.isSubclassOf(overriddenClass, te)) {
                    methlist.remove(i);  // remove overridden method
                    return;
                }
            }
        }
    }

    
Search in the already found methods' list and check if it contains
a method which is overriding the method parameter or is the method
parameter itself.
Params:
method – MethodDoc Method to be searched in the Method List for
an overriding method./**
     * Search in the already found methods' list and check if it contains
     * a method which is overriding the method parameter or is the method
     * parameter itself.
     *
     * @param method MethodDoc Method to be searched in the Method List for
     * an overriding method.
     */
    private boolean overridingMethodFound(ExecutableElement method) {
        TypeElement containingClass = utils.getEnclosingTypeElement(method);
        for (ExecutableElement listmethod : methlist) {
            if (containingClass == utils.getEnclosingTypeElement(listmethod)) {
                // it's the same method.
                return true;
            }
            TypeElement te = utils.overriddenClass(listmethod);
            if (te == null) {
                continue;
            }
            if (te == containingClass || utils.isSubclassOf(te, containingClass)) {
                return true;
            }
        }
        return false;
    }
}