/**
 * 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.Resource;
import de.mpiwg.itgroup.annotations.neo4j.AnnotationStore;

/**
 * API for accessing resource objects in the Annotation store.
 * 
 * @author dwinter
 * 
 */
public class AnnotatorResources 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("AnnotatorResources doGetJSON!");
        setCorsHeaders();

        String jsonId = (String) getRequest().getAttributes().get("id");
        if (jsonId != null) {
            // URL decode
            try {
                jsonId = URLDecoder.decode(jsonId, "UTF-8");
            } catch (UnsupportedEncodingException e) {
                // this shouldn't happen
            }
        }
        String uri = decodeJsonId(jsonId);

        logger.debug("resources-id=" + uri);

        if (uri == null) {
            return getAllResources();
        } else {
            return getResource(uri);
        }
    }

    protected Representation getResource(String uri) {
        AnnotationStore store = getAnnotationStore();
        Node resNode = store.getResourceNodeByUri(uri);
        Resource resource = store.createResourceFromNode(resNode);
        JSONObject jo = new JSONObject();
        try {
            jo.put("id", encodeJsonId(resource.getUri()));
            jo.put("uri", resource.getUri());
        } catch (JSONException e) {
        }

        return new JsonRepresentation(jo);
    }

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

        List<Resource> resources = store.getResources(null, null);
        for (Resource resource : resources) {
            JSONObject jo = new JSONObject();
            try {
                jo.put("id", encodeJsonId(resource.getUri()));
                jo.put("uri", resource.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);
    }

}