/*
 
* Java Genetic Algorithm Library (@__identifier__@).
 
* Copyright (c) @__year__@ Franz Wilhelmstötter
 
*
 
* Licensed under the Apache License, Version 2.0 (the "License");
 
* you may not use this file except in compliance with the License.
 
* You may obtain a copy of the License at
 
*
 
*
      
http://www.apache.org/licenses/LICENSE-2.0
 
*
 
* Unless required by applicable law or agreed to in writing, software
 
* distributed under the License is distributed on an "AS IS" BASIS,
 
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 
* See the License for the specific language governing permissions and
 
* limitations under the License.
 
*
 
* Author:
 
*
    
Franz Wilhelmstötter (franz.wilhelmstoetter@gmail.com)
 
*/
package io.jenetics.jpx.format;

import static java.util.Objects.requireNonNull;
import static io.jenetics.jpx.format.LocationFormatter.PROTECTED_CHARS;

import java.util.Optional;

/**
 
* A format object which returns a constant value.
 
*
 
* @author<a href="mailto:franz.wilhelmstoetter@gmail.com">Franz Wilhelmstötter</a>
 
* @version 1.4
 
* @since 1.4
 
*/

final class ConstFormat<T> implements Format<T> {

	
private final String _value;

	
/**
	 
* Create a new <em>constant</em> location format object.
	 
*
	 
* @param value the constant value, returned by the
	 
*
        
{@link Format#format(Object)} method
	 
*/

	
private ConstFormat(final String value) {
		
_value = requireNonNull(value);
	
}

	
@Override
	
public Optional<String> format(final T value) {
		
return Optional.of(_value);
	
}

	
@Override
	
public String toString() {
		
return escape(_value);
	
}

	
private static String escape(final String value) {
		
final StringBuilder out = new StringBuilder();
		
boolean quote = false;
		
for (int i = 0; i < value.length(); ++i) {
			
final char c = value.charAt(i);
			
if (PROTECTED_CHARS.contains(c)) {
				
quote = true;
			
}
			
if (c == '\'') {
				
out.append(c);
			
}
			
out.append(c);
		
}

		
return quote
			
? "'" + out.toString() + "'"
			
: out.toString();
	
}

	
static <T> ConstFormat<T> of(final String value) {
		
return new ConstFormat<>(value);
	
}

}