/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You 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.
   */
  package org.apache.juneau.commons.lang;
  
  import static org.apache.juneau.commons.utils.ThrowableUtils.*;
  
  import java.util.*;
  
  /**
   * Stores a set of ASCII characters for quick lookup.
   */
  public class AsciiSet {
  	/**
  	 * Builder class.
  	 */
  	public static class Builder {
  		final boolean[] store = new boolean[128];
  
  		/**
  		 * Create a new {@link AsciiSet} object with the contents of this builder.
  		 *
  		 * @return A new {link AsciiSet} object.
  		 */
  		public AsciiSet build() {
  			return new AsciiSet(store);
  		}
  
  		/**
  		 * Adds a set of characters to this set.
  		 *
  		 * @param value The characters to keep in this store.
  		 * @return This object.
  		 */
  		public Builder chars(char...value) {
  			for (var i = 0; i < value.length; i++)
  				if (value[i] < 128)
  					store[value[i]] = true;
  			return this;
  		}
  
  		/**
  		 * Adds a set of characters to this set.
  		 *
  		 * @param value The characters to keep in this store.
  		 * @return This object.
  		 */
  		public AsciiSet.Builder chars(String value) {
  			for (var i = 0; i < value.length(); i++) {
  				var c = value.charAt(i);
  				if (c < 128)
  					store[c] = true;
  			}
  			return this;
  		}
  
  		/**
  		 * Adds a range of characters to this set.
  		 *
  		 * @param start The start character.
  		 * @param end The end character.
  		 * @return This object.
  		 */
  		public AsciiSet.Builder range(char start, char end) {
  			for (var c = start; c <= end; c++)
  				if (c < 128)
  					store[c] = true;
  			return this;
  		}
  
  		/**
  		 * Shortcut for calling multiple ranges.
  		 *
  		 * @param value Strings of the form "A-Z" where A and Z represent the first and last characters in the range.
  		 * @return This object.
  		 */
  		public AsciiSet.Builder ranges(String...value) {
  			for (var ss : value) {
  				if (ss.length() != 3 || ss.charAt(1) != '-')
  					throw illegalArg("Value passed to ranges() must be 3 characters");
  				range(ss.charAt(0), ss.charAt(2));
  			}
  			return this;
  		}
  	}
  
 	/**
 	 * Creates a builder for an ASCII set.
 	 *
 	 * @return A new builder.
 	 */
 	public static AsciiSet.Builder create() {
 		return new Builder();
 	}
 
 	/**
 	 * Creates an ASCII set with the specified characters.
 	 *
 	 * @param value The characters to keep in this store.
 	 * @return A new object.
 	 */
 	public static AsciiSet of(String value) {
 		return new Builder().chars(value).build();
 	}
 
 	private final boolean[] store;
 
 	AsciiSet(boolean[] store) {
 		this.store = Arrays.copyOf(store, store.length);
 	}
 
 	/**
 	 * Returns <jk>true</jk> if the specified character is in this store.
 	 *
 	 * @param value The character to check.
 	 * @return <jk>true</jk> if the specified character is in this store.
 	 */
 	public boolean contains(char value) {
 		if (value > 127)
 			return false;
 		return store[value];
 	}
 
 	/**
 	 * Returns <jk>true</jk> if the specified string contains at least one character in this set.
 	 *
 	 * @param value The string to test.
 	 * @return <jk>true</jk> if the string is not null and contains at least one character in this set.
 	 */
 	public boolean contains(CharSequence value) {
 		if (value == null)
 			return false;
 		for (var i = 0; i < value.length(); i++)
 			if (contains(value.charAt(i)))
 				return true;
 		return false;
 	}
 
 	/**
 	 * Returns <jk>true</jk> if the specified character is in this store.
 	 *
 	 * @param value The character to check.
 	 * @return <jk>true</jk> if the specified character is in this store.
 	 */
 	public boolean contains(int value) {
 		if (value < 0 || value > 127)
 			return false;
 		return store[value];
 	}
 
 	/**
 	 * Returns <jk>true</jk> if the specified string contains only characters in this set.
 	 *
 	 * @param value The string to test.
 	 * @return
 	 * 	<jk>true</jk> if the string contains only characters in this set.
 	 * 	<br>Nulls always return <jk>false</jk>.
 	 * 	<br>Blanks always return <jk>true</jk>.
 	 */
 	public boolean containsOnly(String value) {
 		if (value == null)
 			return false;
 		for (var i = 0; i < value.length(); i++)
 			if (! contains(value.charAt(i)))
 				return false;
 		return true;
 	}
 
 	/**
 	 * Copies an existing {@link AsciiSet} so that you can augment it with additional values.
 	 *
 	 * @return A builder initialized to the same characters in the copied set.
 	 */
 	public AsciiSet.Builder copy() {
 		var b = new Builder();
 		System.arraycopy(store, 0, b.store, 0, 128);
 		return b;
 	}
 }