/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

import {Trie} from './Trie.js';

/**
 * @unrestricted
 */
export class TextDictionary {
  constructor() {
    /** @type {!Map<string, number>} */
    this._words = new Map();
    this._index = new Trie();
  }

  /**
   * @param {string} word
   */
  addWord(word) {
    let count = this._words.get(word) || 0;
    ++count;
    this._words.set(word, count);
    this._index.add(word);
  }

  /**
   * @param {string} word
   */
  removeWord(word) {
    let count = this._words.get(word) || 0;
    if (!count) {
      return;
    }
    if (count === 1) {
      this._words.delete(word);
      this._index.remove(word);
      return;
    }
    --count;
    this._words.set(word, count);
  }

  /**
   * @param {string} prefix
   * @return {!Array.<string>}
   */
  wordsWithPrefix(prefix) {
    return this._index.words(prefix);
  }

  /**
   * @param {string} word
   * @return {boolean}
   */
  hasWord(word) {
    return this._words.has(word);
  }

  /**
   * @param {string} word
   * @return {number}
   */
  wordCount(word) {
    return this._words.get(word) || 0;
  }

  reset() {
    this._words.clear();
    this._index.clear();
  }
}