HueSettings.java

/**
 * Copyright (c) 2010-2016 by the respective copyright holders.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */
package org.openhab.binding.hue.internal.data;

import java.io.IOException;
import java.util.Map;
import java.util.Set;

import org.codehaus.jackson.JsonNode;
import org.codehaus.jackson.map.ObjectMapper;
import org.openhab.binding.hue.internal.hardware.HueBulb;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Contains all information that is provided by the Hue bridge. There are
 * different information that can be requested about the connected bulbs.
 * <ul>
 * <li>Is a bulb switched on?</li>
 * <li>How is a bulb's color temperature?</li>
 * <li>How is the current brightness of a blub?</li>
 * <li>How is the hue of a given bulb?</li>
 * <li>How is the saturation of a given bulb?</li>
 * </ul>
 *
 * @author Roman Hartmann
 * @author Jos Schering
 * @author Markus Mazurczak - Added function to retrieve the model ID of a bulb
 * @since 1.2.0
 */
public class HueSettings {

    static final Logger logger = LoggerFactory.getLogger(HueSettings.class);

    private SettingsTree settingsData = null;
    private static final int ERROR_TYPE_UNAUTHORIZED_USER = 1;
    private boolean isAuthorized = false;

    /**
     * Constructor of HueSettings. It takes the settings of the Hue bridge to enable the HueSettings to determine the
     * needed information about the bulbs.
     * 
     * @param settings
     *            This is the settings string in Json format returned by the Hue bridge.
     */
    @SuppressWarnings("unchecked")
    public HueSettings(String settings) {
        ObjectMapper mapper = new ObjectMapper();
        try {
            JsonNode rootNode = mapper.readTree(settings);
            if (!isAuthorizationError(rootNode)) {
                settingsData = new SettingsTree(mapper.readValue(rootNode, Map.class));
                isAuthorized = true;
            }
        } catch (IOException e) {
            logger.error("Could not read Settings-Json from Hue Bridge.", e);
        }
    }

    /**
     * Determines if the Hue Bridge reported an authorization error.
     * 
     * @return true if an authorization error occurred, else false
     */
    private boolean isAuthorizationError(JsonNode rootNode) {
        boolean isAuthorizationError = false;
        // While normal answers from the bridge are of type object, the error message is of type array
        if (rootNode.isArray()) {
            JsonNode node = rootNode.get(0);
            if (node.has("error")) {
                if (node.get("error").get("type").getIntValue() == ERROR_TYPE_UNAUTHORIZED_USER) {
                    isAuthorizationError = true;
                }
            }
        }
        return isAuthorizationError;
    }

    /**
     * Returns the model-ID of the bulb
     * 
     * @param deviceId The bulb id the bridge has filed the bulb under.
     * @return The model-ID. Null if Hue bridge is not initialized correctly or if the ID was not parsed correctly
     */
    public String getModelId(String deviceId) {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return null;
        }
        Object modelId = settingsData.node("lights").node(deviceId).value("modelid");
        return modelId != null ? modelId.toString() : null;
    }

    /**
     * @return True if openHAB is authorized on the Hue bridge, else false
     */
    public boolean isAuthorized() {
        return isAuthorized;
    }

    /**
     * Return the keys of lights connected to Hue hub
     * 
     * @return the keys of lights connected to Hue hub
     */
    public Set<String> getKeys() {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return null;
        }
        return settingsData.node("lights").getKeys();
    }

    /**
     * Determines whether the given bulb is valid in the settings of the bridge.
     * 
     * @param deviceId
     *            The bulb id the bridge has filed the bulb under.
     * @return true if the bulb is turned on, false otherwise.
     */
    public boolean isValidId(String deviceId) {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return false;
        }
        return settingsData.node("lights").node(deviceId) != null;
    }

    /**
     * Determines whether the given bulb is turned on.
     * 
     * @param deviceId
     *            The bulb id the bridge has filed the bulb under.
     * @return true if the bulb is turned on, false otherwise.
     */
    public boolean isBulbOn(String deviceId) {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return false;
        }
        return (Boolean) settingsData.node("lights").node(deviceId).node("state").value("on");
    }

    /**
     * Determines whether the given bulb is reachable.
     * Once a bulb is physical disconnected it becomes unreachable after around 10 seconds.
     * The hearbeat service of the Hue hub device is responsible for this behavior.
     * 
     * @param deviceId
     *            The bulb id the bridge has filed the bulb under.
     * @return true if the bulb is reachable, false otherwise.
     */
    public boolean isReachable(String deviceId) {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return false;
        }
        return (Boolean) settingsData.node("lights").node(deviceId).node("state").value("reachable");
    }

    /**
     * Determines the color temperature of the given bulb.
     * 
     * @param deviceId
     *            The bulb id the bridge has filed the bulb under.
     * @return The color temperature as a value from 154 - 500
     */
    public int getColorTemperature(String deviceId) {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return 154;
        }
        Object ct = settingsData.node("lights").node(deviceId).node("state").value("ct");
        if (ct instanceof Integer) {
            return (Integer) ct;
        } else {
            return 154;
        }
    }

    /**
     * Determines the brightness of the given bulb.
     * 
     * @param deviceId
     *            The bulb id the bridge has filed the bulb under.
     * @return The brightness as a value from 0 - {@link HueBulb#MAX_BRIGHTNESS}
     */
    public int getBrightness(String deviceId) {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return 0;
        }
        Object bri = settingsData.node("lights").node(deviceId).node("state").value("bri");
        if (bri instanceof Integer) {
            return (Integer) bri;
        } else {
            // probably not dimmable, return on state
            return isBulbOn(deviceId) ? 254 : 0;
        }
    }

    /**
     * Determines the hue of the given bulb.
     * 
     * @param deviceId
     *            The bulb id the bridge has filed the bulb under.
     * @return The hue as a value from 0 - 65535
     */
    public int getHue(String deviceId) {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return 0;
        }

        Object hue = settingsData.node("lights").node(deviceId).node("state").value("hue");
        if (hue instanceof Integer) {
            return (Integer) hue;
        } else {
            return 0;
        }
    }

    /**
     * Determines the saturation of the given bulb.
     * 
     * @param deviceId
     *            The bulb id the bridge has filed the bulb under.
     * @return The saturation as a value from 0 - {@link HueBulb#MAX_BRIGHTNESS}
     */
    public int getSaturation(String deviceId) {
        if (settingsData == null) {
            logger.error("Hue bridge settings not initialized correctly.");
            return 0;
        }

        Object sat = settingsData.node("lights").node(deviceId).node("state").value("sat");
        if (sat instanceof Integer) {
            return (Integer) sat;
        } else {
            return 0;
        }
    }

    /**
     * The SettingsTree represents the settings Json as a tree with some
     * convenience methods to get subtrees and the values of interest easily.
     */
    class SettingsTree {

        private Map<String, Object> dataMap;

        /**
         * Constructor of the SettingsTree.
         * 
         * @param treeData
         *            The Json data as it has been returned by the Json object
         *            mapper.
         */
        public SettingsTree(Map<String, Object> treeData) {
            this.dataMap = treeData;
        }

        /**
         * @param nodeName
         *            The name of the child node.
         * @return The child node named like nodeName. This will be a sub tree.
         */
        @SuppressWarnings("unchecked")
        protected SettingsTree node(String nodeName) {
            if (dataMap.get(nodeName) == null){
                return null;
            }

            return new SettingsTree((Map<String, Object>) dataMap.get(nodeName));
        }

        /**
         * @return the amount of lights connected to Hue hub
         */
        protected int count() {
            return dataMap.size();
        }

        protected Set<String> getKeys() {
            return dataMap.keySet();
        }

        /**
         * @param valueName
         *            The name of the child node.
         * @return The child node named like nodeName. This will be an object.
         */
        protected Object value(String valueName) {
            return dataMap.get(valueName);
        }

    }

}