source: trunk/gsdl3/src/java/org/greenstone/gsdl3/util/CGIArgConverter.java@ 3618

package org.greenstone.gsdl3.util;

import java.util.HashMap;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

/** converts long names for parameters into short names for cgi args, and vice versa */
public class CGIArgConverter {

    /** long to short mapping */
    protected HashMap long_map_=null;
    /** short to long mapping */
    protected HashMap short_map_=null;
    
    /** initialises the maps with known parameters */
    public CGIArgConverter() {
    long_map_ = new HashMap();
    short_map_ = new HashMap();

    // initialize with the ones we know about
    short_map_.put("a", "action"); 
    long_map_.put("action", "a");

    short_map_.put("sa", "subaction"); 
    long_map_.put("subaction", "sa");   

    short_map_.put("sn", "serviceName"); 
    long_map_.put("serviceName", "sn"); 

    short_map_.put("sc", "serviceCluster");
    long_map_.put("serviceCluster", "sc");

    short_map_.put("l", "lang"); 
    long_map_.put("lang", "l");

    short_map_.put("c", "collection"); 
    long_map_.put("collection", "c");

    long_map_.put("resource", "r");
    short_map_.put("r", "resource");

    // these are service specific - should we have these here??
    long_map_.put("case", "k");
    short_map_.put("k", "case");

    long_map_.put("stem", "s");
    short_map_.put("s", "stem");
    
    long_map_.put("queryLevel", "ql");
    short_map_.put("ql", "queryLevel");
    
    long_map_.put("index", "i");
    short_map_.put("i", "index");
    
    long_map_.put("matchMode", "mm");
    short_map_.put("mm", "matchMode");

    long_map_.put("sortBy", "sb");
    short_map_.put("sb", "sortBy");
    
    long_map_.put("maxDocs", "md");
    short_map_.put("md", "maxDocs");

    long_map_.put("query", "q");
    short_map_.put("q", "query");
    
    short_map_.put("cl", "classifier"); 
    long_map_.put("classifier", "cl");
    }

    /** takes a paramList element  - contains <param name="x"> elements
     * converts all the short names to long names 
     * returns true if successful, false otherwise */
    public boolean toLong(Element param_list) {
    
    if (!param_list.getNodeName().equals(GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER)) {
        System.err.println("CGIArgConverter Error: wrong element passed to toLong");
        return false;
    }
    NodeList params = param_list.getElementsByTagName(GSXML.PARAM_ELEM);
    for (int i=0; i< params.getLength(); i++) {
        Element param = (Element)params.item(i);
        String name = param.getAttribute(GSXML.NAME_ATT);
        param.setAttribute(GSXML.NAME_ATT, toLong(name));
    }
    return true;

    }
    /** adds shortnames to the params in the list */
    public boolean addShortNames(Element param_list) {
    if (!param_list.getNodeName().equals(GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER)) {
        System.err.println("CGIArgConverter Error: wrong element passed to addShortNames");
        return false;
    }
    
    NodeList params = param_list.getElementsByTagName(GSXML.PARAM_ELEM);
    for (int i=0; i< params.getLength(); i++) {
        Element param = (Element)params.item(i);
        String name = param.getAttribute(GSXML.NAME_ATT);
        param.setAttribute(GSXML.PARAM_SHORTNAME_ATT, toShort(name));
    }
    return true;

    }
    
    /** returns the long form of a short arg - 
     * returns the original if it doesn't know about this short arg */
    public String toLong(String short_name) {
    
    if (short_map_.containsKey(short_name)) {
        return (String)short_map_.get(short_name);
    }
    return short_name; // just return the original
    }
    /** returns the short form of a long arg */
    public String toShort(String long_name) {

    if (long_map_.containsKey(long_name)) {
        return (String)long_map_.get(long_name);
    }

    // else need to create a new mapping
    String short_name = newShortName(long_name);
    long_map_.put(long_name, short_name);
    short_map_.put(short_name, long_name);
    return short_name;
    }
    
    /** tries to create a new short form of the long name - 
     * if it cant, it just returns the original name */
    protected String newShortName(String long_name) {
    
    // for now, try the first letter, then first two etc.
    int i=1;
    String short_try= long_name.substring(0,1);
    while(short_map_.containsKey(short_try)&& i<long_name.length()) {
        i++;
        short_try = long_name.substring(0, i);
    }
    return short_try;
    
    }
}