/**
 * ReST API for accessing groups in the Annotation store.
 */
package de.mpiwg.itgroup.annotations.restlet;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.util.List;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.neo4j.graphdb.Node;
import org.restlet.data.Status;
import org.restlet.ext.json.JsonRepresentation;
import org.restlet.representation.Representation;
import org.restlet.resource.Get;

import de.mpiwg.itgroup.annotations.Tag;
import de.mpiwg.itgroup.annotations.neo4j.AnnotationStore;

/**
 * API for accessing tags in the Annotation store.
 * 
 * @author dwinter
 * 
 */
public class AnnotatorTags extends AnnotatorResourceImpl {
    protected String getAllowedMethodsForHeader() {
        return "OPTIONS,GET";
    }

    /**
     * GET with JSON content-type. 
     * Parameters: 
     *   user: short user name 
     *   uri: user uri
     * 
     * @param entity
     * @return
     */
    @Get("json")
    public Representation doGetJSON(Representation entity) {
        logger.debug("AnnotatorGroups doGetJSON!");
        setCorsHeaders();

        String jsonId = (String) getRequest().getAttributes().get("id");
        // String id = decodeJsonId(jsonId);
        String id = jsonId;
        logger.debug("annotation-id=" + id);

        if (id == null) {
            return getAllTags();
        } else {
            // URL decode
            try {
                id = URLDecoder.decode(id, "UTF-8");
            } catch (UnsupportedEncodingException e) {
                // this shouldn't happen
            }
            return getTag(id);
        }
    }

    protected Representation getTag(String id) {
        AnnotationStore store = getAnnotationStore();
        String tagUri = BaseRestlet.TAGS_URI_PREFIX + id;
        Node tagNode = store.getTagNodeByUri(tagUri);
        Tag tag = store.createTagFromNode(tagNode);
        JSONObject jo = new JSONObject();
        try {
            jo.put("id", tag.getId());
            jo.put("name", tag.getName());
            jo.put("uri", tag.getUri());
        } catch (JSONException e) {
        }

        return new JsonRepresentation(jo);
    }

    protected Representation getAllTags() {
        JSONArray results = new JSONArray();
        AnnotationStore store = getAnnotationStore();

        List<Tag> tags = store.getTags(null, null);
        for (Tag tag : tags) {
            JSONObject jo = new JSONObject();
            try {
                jo.put("id", tag.getId());
                jo.put("name", tag.getName());
                jo.put("uri", tag.getUri());
            } catch (JSONException e) {
            }
            results.put(jo);
        }

        // assemble result object
        JSONObject result = new JSONObject();
        try {
            result.put("rows", results);
            result.put("total", results.length());
        } catch (JSONException e) {
            setStatus(Status.SERVER_ERROR_INTERNAL, "JSON Error");
            return null;
        }
        logger.debug("sending:");
        logger.debug(result);
        return new JsonRepresentation(result);
    }

}