YamahaReceiverProxy.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.yamahareceiver.internal.hardware;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.StringReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.openhab.binding.yamahareceiver.internal.YamahaReceiverBindingConfig.Zone;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;

/**
 * Yamaha Receiver Proxy used to control a yamaha receiver with HTTP/XML
 *
 * @author Eric Thill
 * @author Ben Jones
 * @since 1.6.0
 */
public class YamahaReceiverProxy {

    public static final int VOLUME_MIN = -80;
    public static final int VOLUME_MAX = 16;

    private final DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

    private final String host;

    public YamahaReceiverProxy(String host) {
        this.host = host;
    }

    public String getHost() {
        return host;
    }

    public void setPower(Zone zone, boolean on) throws IOException {
        if (on) {
            postAndGetResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"PUT\"><" + zone
                    + "><Power_Control><Power>On</Power></Power_Control></" + zone + "></YAMAHA_AV>");
        } else {
            postAndGetResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"PUT\"><" + zone
                    + "><Power_Control><Power>Standby</Power></Power_Control></" + zone + "></YAMAHA_AV>");
        }
    }

    public void setVolume(Zone zone, float volume) throws IOException {
        postAndGetResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"PUT\"><" + zone
                + "><Volume><Lvl><Val>" + (int) (volume * 10) + "</Val><Exp>1</Exp><Unit>dB</Unit></Lvl></Volume></"
                + zone + "></YAMAHA_AV>");
    }

    public void setMute(Zone zone, boolean mute) throws IOException {
        if (mute) {
            postAndGetResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"PUT\"><" + zone
                    + "><Volume><Mute>On</Mute></Volume></" + zone + "></YAMAHA_AV>");
        } else {
            postAndGetResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"PUT\"><" + zone
                    + "><Volume><Mute>Off</Mute></Volume></" + zone + "></YAMAHA_AV>");
        }
    }

    public void setInput(Zone zone, String name) throws IOException {
        postAndGetResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"PUT\"><" + zone
                + "><Input><Input_Sel>" + name + "</Input_Sel></Input></" + zone + "></YAMAHA_AV>");
    }

    public void setSurroundProgram(Zone zone, String name) throws IOException {
        postAndGetResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"PUT\"><" + zone
                + "><Surround><Program_Sel><Current><Sound_Program>" + name
                + "</Sound_Program></Current></Program_Sel></Surround></" + zone + "></YAMAHA_AV>");
    }

    public void setNetRadio(int lineNo) throws IOException {
        /* Jump to specified line in preset list */
        postAndGetResponse(
                "<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"PUT\"><NET_RADIO><Play_Control><Preset><Preset_Sel>"
                        + lineNo + "</Preset_Sel></Preset></Play_Control></NET_RADIO></YAMAHA_AV>");
    }

    public YamahaReceiverState getState(Zone zone) throws IOException {
        Document doc = postAndGetXmlResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"GET\"><" + zone
                + "><Basic_Status>GetParam</Basic_Status></" + zone + "></YAMAHA_AV>");
        Node basicStatus = getNode(doc.getFirstChild(), "" + zone + "/Basic_Status");

        Node powerNode = getNode(basicStatus, "Power_Control/Power");
        boolean power = powerNode != null ? "On".equalsIgnoreCase(powerNode.getTextContent()) : false;
        Node inputNode = getNode(basicStatus, "Input/Input_Sel");
        String input = inputNode != null ? inputNode.getTextContent() : null;
        Node soundProgramNode = getNode(basicStatus, "Surround/Program_Sel/Current/Sound_Program");
        String soundProgram = soundProgramNode != null ? soundProgramNode.getTextContent() : null;
        Node volumeNode = getNode(basicStatus, "Volume/Lvl/Val");
        float volume = volumeNode != null ? Float.parseFloat(volumeNode.getTextContent()) * .1f : VOLUME_MIN;
        Node muteNode = getNode(basicStatus, "Volume/Mute");
        boolean mute = muteNode != null ? "On".equalsIgnoreCase(muteNode.getTextContent()) : false;

        return new YamahaReceiverState(power, input, soundProgram, volume, mute);
    }

    public List<String> getInputsList(Zone zone) throws IOException {
        List<String> names = new ArrayList<String>();
        Document doc = postAndGetXmlResponse("<?xml version=\"1.0\" encoding=\"utf-8\"?><YAMAHA_AV cmd=\"GET\"><" + zone
                + "><Input><Input_Sel_Item>GetParam</Input_Sel_Item></Input></" + zone + "></YAMAHA_AV>");
        Node inputSelItem = getNode(doc.getFirstChild(), zone + "/Input/Input_Sel_Item");
        NodeList items = inputSelItem.getChildNodes();
        for (int i = 0; i < items.getLength(); i++) {
            Element item = (Element) items.item(i);
            String name = item.getElementsByTagName("Param").item(0).getTextContent();
            boolean writable = item.getElementsByTagName("RW").item(0).getTextContent().contains("W");
            if (writable) {
                names.add(name);
            }
        }
        return names;
    }

    private static Node getNode(Node root, String nodePath) {
        String[] nodePathArr = nodePath.split("/");
        return getNode(root, nodePathArr, 0);
    }

    private static Node getNode(Node parent, String[] nodePath, int offset) {
        if (parent == null) {
            return null;
        }
        if (offset < nodePath.length - 1) {
            return getNode(((Element) parent).getElementsByTagName(nodePath[offset]).item(0), nodePath, offset + 1);
        } else {
            return ((Element) parent).getElementsByTagName(nodePath[offset]).item(0);
        }
    }

    private Document postAndGetXmlResponse(String message) throws IOException {
        String response = postAndGetResponse(message);
        String xml = response.toString();
        try {
            DocumentBuilder db = dbf.newDocumentBuilder();
            return db.parse(new InputSource(new StringReader(xml)));
        } catch (Exception e) {
            throw new IOException("Could not handle response", e);
        }
    }

    private String postAndGetResponse(String message) throws IOException {
        HttpURLConnection connection = null;
        try {
            URL url = new URL("http://" + host + "/YamahaRemoteControl/ctrl");
            connection = (HttpURLConnection) url.openConnection();
            connection.setRequestMethod("POST");
            connection.setRequestProperty("Content-Length", "" + Integer.toString(message.length()));

            connection.setUseCaches(false);
            connection.setDoInput(true);
            connection.setDoOutput(true);

            // Send request
            DataOutputStream wr = new DataOutputStream(connection.getOutputStream());
            wr.writeBytes(message);
            wr.flush();
            wr.close();

            // Read response
            InputStream is = connection.getInputStream();
            BufferedReader rd = new BufferedReader(new InputStreamReader(is));
            String line;
            StringBuffer response = new StringBuffer();
            while ((line = rd.readLine()) != null) {
                response.append(line);
                response.append('\r');
            }
            rd.close();
            return response.toString();
        } catch (Exception e) {
            throw new IOException("Could not handle http post", e);
        } finally {
            if (connection != null) {
                connection.disconnect();
            }
        }
    }
}