/*******************************************************************************
 * Copyright (c) 2010 Haifeng Li
 *   
 * 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.
 *******************************************************************************/

package smile.nlp;

import java.util.Arrays;
import java.util.HashMap;

/**
 * A list-of-words representation of documents.
 *
 * @author Haifeng Li
 */
public class SimpleText extends Text implements TextTerms, AnchorText {
    /**
     * All anchor text in the corpus pointing to this text.
     */
    private String anchor;

    /**
     * The list of words.
     */
    private String[] words;
    /**
     * The term frequency.
     */
    private HashMap freq = new HashMap<>();
    /**
     * The maximum term frequency over all terms in the documents;
     */
    private int maxtf;

    /**
     * Constructor.
     * @param id the id of document.
     * @param words the word list of document.
     */
    public SimpleText(String id, String title, String body, String[] words) {
    	super(id, title, body);

        this.words = words;

        for (String w : words) {
            Integer f = freq.get(w);
            if (f == null) {
                f = 1;
            } else {
                f = f + 1;
            }

            freq.put(w, f);

            if (f > maxtf) {
                maxtf = f;
            }
        }
    }
    
    @Override
    public int size() {
        return words.length;
    }

    @Override
    public Iterable words() {
        return Arrays.asList(words);
    }

    @Override
    public Iterable unique() {
        return freq.keySet();
    }
    
    @Override
    public int tf(String term) {
        Integer f = freq.get(term);
        
        if (f == null) {
            return 0;
        }
        
        return f;
    }

    @Override
    public int maxtf() {
        return maxtf;
    }

    /**
     * Returns the anchor text if any. The anchor text is the visible,
     * clickable text in a hyperlink. The anchor text is all the
     * anchor text in the corpus pointing to this text.
     */
    public String getAnchor() {
    	return anchor;
    }
    
    /**
     * Sets the anchor text. Note that anchor is all link labels in the corpus
     * pointing to this text. So addAnchor is more appropriate in most cases.
     */
    public SimpleText setAnchor(String anchor) {
    	this.anchor = anchor;
        return this;
    }
    
    public SimpleText addAnchor(String linkLabel) {
    	if (anchor == null) {
    		anchor = linkLabel;
    	} else {
    		anchor = anchor + " " + linkLabel;
    	}
        return this;
    }
    
    @Override
    public String toString() {
        return String.format("Document[%s%s]", getID(), getTitle() == null ? "" : " -- "+ getTitle());
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }

        if (getClass() != obj.getClass()) {
            return false;
        }

        final SimpleText other = (SimpleText) obj;
        return getID().equals(other.getID());
    }

    @Override
    public int hashCode() {
    	return getID().hashCode();
    }
}