package th.co.muangthai.endrprint.util;

/**
 * Created by IntelliJ IDEA.
 * User: Zizu
 * Date: 6/25/14
 * Time: 4:16 PM
 * To change this template use File | Settings | File Templates.
 */

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.Set;

/**
 * This class can be used for reflection purpose. Both class should match the getter and setter.
 * @author Vijay Shegokar
 * @version 1.0
 */
public class ReflectionUtil {

    /**
     * This method is used to copy one bean values to another bean.
     * @param toClazz Class object of Destination bean, which will be used to create class instance to copy values from passed object
     * @param from Origin bean from where to copy values
     * @param strictCopy boolean value denoting that copy should be in strict manner or not. If this is true then null values will also copied to destination bean from origin bean
     * @throws IllegalArgumentException If passed bean is null.
     * @throws InvocationTargetException If method access is denied
     * @throws InstantiationException If not able to create an instance of an passed toClass
     * @throws IllegalAccessException If access denied to access given class
     */
    @SuppressWarnings("unchecked")
    public static <T> T copy(Class<T> toClazz, Object from, boolean strictCopy) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
        if (toClazz == null)
            throw new IllegalArgumentException("No destination bean specified");
        Object to = toClazz.newInstance();
        copy(to, from, strictCopy);
        return (T)to;
    }

    /**
     * This method is used to copy one bean values to another bean.
     * @param toClazz Class object of Destination bean, which will be used to create class instance to copy values from passed object
     * @param from Origin bean from where to copy values
     * @throws IllegalArgumentException If passed bean is null.
     * @throws InvocationTargetException If method access is denied
     * @throws InstantiationException If not able to create an instance of an passed toClass
     * @throws IllegalAccessException If access denied to access given class
     */
    public static <T> T copy(Class<T> toClazz, Object from) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
        return copy(toClazz, from, false);
    }

    /**
     * This method is used to copy one bean values to another bean.
     * @param to : Destination bean where values need to be copy from origin
     * @param from : Origin bean from where to copy values
     * @throws IllegalArgumentException If passed bean is null.
     * @throws InvocationTargetException If method access is denied
     */
    public static void copy(final Object to, final Object from) throws IllegalArgumentException, InvocationTargetException {
        copy(to, from, false);
    }

    /**
     * This method is used to copy one bean values to another bean.
     * @param to : Origin bean from where to copy values
     * @param from : Destination bean where values need to be copy from origin
     * @param strictCopy boolean value denoting that copy should be in strict manner or not. If this is true then null values will also copied to destination bean from origin bean
     * @throws IllegalArgumentException If passed bean is null.
     * @throws InvocationTargetException If method access is denied
     */
    synchronized public static void copy(final Object to, final Object from, boolean strictCopy) throws IllegalArgumentException, InvocationTargetException{
        // long t1 = System.currentTimeMillis();
        // System.out.println("Time Sarted : " + t1);
        // Validate existence of the specified beans
        if (to == null) {
            throw new IllegalArgumentException("No destination bean specified");
        }
        if (from == null) {
            throw new IllegalArgumentException("No origin bean specified");
        }
        try {
            Class<? extends Object> toClass = to.getClass();
            Method[] toMethods = toClass.getMethods();
            Set<Method> toMethodsList = new LinkedHashSet<Method>(Arrays.asList(toMethods));

            Class<? extends Object> fromClass = from.getClass();
            Method[] fromMethods = fromClass.getMethods();
            Set<Method> fromMethodsList = new LinkedHashSet<Method>(Arrays.asList(fromMethods));

            Iterator<Method> fromMethodsIterator = fromMethodsList.iterator();
            while(fromMethodsIterator.hasNext()) {
                Method fromMethod = fromMethodsIterator.next();
                boolean isBoolean = false;
                Class<?> returnType = fromMethod.getReturnType();
                if(fromMethod.getName().startsWith("is") && boolean.class.equals(returnType)) {
                    isBoolean = true;
                }
                if (isGetter(fromMethod, isBoolean)) {
                    Object value = null;
                    try {
                        value = fromMethod.invoke(from);
                    } catch (Exception e) {
                        throw new InvocationTargetException(e, "Getter method cannot have any parameter. Error on method : " + fromMethod.getName());
                    }
                    if(strictCopy){
                        setValues(returnType, value, fromMethod, to, toMethodsList, isBoolean);
                    } else {
                        if(value != null) {
                            setValues(returnType, value, fromMethod, to, toMethodsList, isBoolean);
                        }
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {

        }
        // long t2 = System.currentTimeMillis();
        // System.out.println("Time completed : " + t2);
        // System.out.println("Total Time completed : " + (t2 - t1));
    }

    /**
     * This method is used to check method is getter or not.
     * @param method Method which needs to be check
     * @param isBoolean If the given method is primitive boolean type because getter for it starts with "is".
     * @return true is method is getter
     */
    public static boolean isGetter(Method method, boolean isBoolean) {
        if(isBoolean && !method.getName().startsWith("is"))
            return false;
        if (!isBoolean && !method.getName().startsWith("get"))
            return false;
        if (method.getParameterTypes().length != 0)
            return false;
        if (void.class.equals(method.getReturnType()))
            return false;
        return true;
    }

    /**
     * This method is used to check method is setter or not.
     * @param method Method which needs to be check
     * @return true is method is setter
     */
    public static boolean isSetter(Method method) {
        if (!method.getName().startsWith("set"))
            return false;
        if (method.getParameterTypes().length != 1)
            return false;
        return true;
    }

    /**
     * This method set the values to destination bean
     * @param returnType Return type of from class method
     * @param value value of from class getter method to be copied to destination
     * @param fromMethod method of from class
     * @param to destination class object
     * @param toMethodsList set of to class all methods
     * @param isBoolean method return type is boolean or not
     * @throws IllegalArgumentException If passed bean is null.
     * @throws InvocationTargetException If method access is denied
     * @throws IllegalAccessException If access denied to access given class
     */
    public static void setValues(Class<?> returnType, Object value, final Method fromMethod, final Object to, Set<Method> toMethodsList, boolean isBoolean) throws IllegalArgumentException, IllegalAccessException, InvocationTargetException{
        if(!returnType.isPrimitive()) {
            fromMethod.getReturnType().cast(value);
        }
        Iterator<Method> toMethodsIterator = toMethodsList.iterator();
        while (toMethodsIterator.hasNext()) {
            Method toMethod = (Method) toMethodsIterator.next();
            if (isSetter(toMethod)) {
                int fromSubstringIndex = 3;
                if(isBoolean)
                    fromSubstringIndex = 2;
                if(toMethod.getName().substring(3).equals(fromMethod.getName().substring(fromSubstringIndex))) {
                    try {
                        toMethod.invoke(to, value);
                    } catch (Exception e) {
                        throw new InvocationTargetException(e, "Data type mismatched or access specifier is wrong. Error on method: TO method = " + toMethod.getName() + " FROM method = " + fromMethod.getName());
                    }
                    toMethodsList.remove(toMethod);
                    break;
                }
            }
        }
    }

}