implement media keys api, version 1.0.7

Author: LabyStudio

README.md

@@ -7,6 +7,14 @@ because the API reads the information directly from the application itself.
 #### Supported operating systems:
 - Windows
 
+## Feature Overview
+- Track id
+- Track title & artist
+- Track progress & length
+- Playing state (Playing, paused)
+- Track cover
+- Media keys (Previous song, play/pause & next song)
+
 ## Gradle Setup
 ```groovy
 repositories {
@@ -96,3 +104,11 @@ OpenSpotifyAPI openSpotifyAPI = new OpenSpotifyAPI();
 // Download the cover art of the current song
 BufferedImage imageTrackCover = openSpotifyAPI.requestImage(track);
 ```
+
+You can also skip the current song using the Media Key API:
+```java
+SpotifyAPI api = SpotifyAPIFactory.createInitialized();
+
+// Send media key to the operating system
+api.pressMediaKey(MediaKey.NEXT);
+```

build.gradle

@@ -4,7 +4,7 @@ plugins {
 }
 
 group 'de.labystudio'
-version '1.0.6'
+version '1.0.7'
 
 compileJava {
     sourceCompatibility = '1.8'

src/main/java/de/labystudio/spotifyapi/SpotifyAPI.java

@@ -1,5 +1,6 @@
 package de.labystudio.spotifyapi;
 
+import de.labystudio.spotifyapi.model.MediaKey;
 import de.labystudio.spotifyapi.model.Track;
 
 import java.util.concurrent.CompletableFuture;
@@ -71,6 +72,19 @@ default boolean hasTrack() {
      */
     boolean isPlaying();
 
+    /**
+     * Send a key pres of a media key to the system.<br>
+     * The key can be one of the following:
+     * <ul>
+     *     <li>{@link MediaKey#PLAY_PAUSE}</li>
+     *     <li>{@link MediaKey#NEXT}</li>
+     *     <li>{@link MediaKey#PREV}</li>
+     * </ul>
+     *
+     * @param mediaKey the key to send
+     */
+    void pressMediaKey(MediaKey mediaKey);
+
     /**
      * Returns true if the api is connected to the Spotify application.
      *

src/main/java/de/labystudio/spotifyapi/model/MediaKey.java

@@ -0,0 +1,7 @@
+package de.labystudio.spotifyapi.model;
+
+public enum MediaKey {
+    PLAY_PAUSE,
+    NEXT,
+    PREV
+}

src/main/java/de/labystudio/spotifyapi/platform/osx/OSXSpotifyApi.java

@@ -1,6 +1,7 @@
 package de.labystudio.spotifyapi.platform.osx;
 
 import de.labystudio.spotifyapi.SpotifyAPI;
+import de.labystudio.spotifyapi.model.MediaKey;
 import de.labystudio.spotifyapi.model.Track;
 import de.labystudio.spotifyapi.platform.AbstractSpotifyAPI;
 
@@ -40,6 +41,11 @@ public boolean hasPosition() {
         return false; // TODO Implement OSX SpotifyAPI
     }
 
+    @Override
+    public void pressMediaKey(MediaKey mediaKey) {
+
+    }
+
     @Override
     public boolean isPlaying() {
         return false; // TODO Implement OSX SpotifyAPI

src/main/java/de/labystudio/spotifyapi/platform/windows/WinSpotifyAPI.java

@@ -1,6 +1,8 @@
 package de.labystudio.spotifyapi.platform.windows;
 
 import de.labystudio.spotifyapi.SpotifyAPI;
+import de.labystudio.spotifyapi.model.MediaKey;
+import de.labystudio.spotifyapi.platform.windows.api.WinApi;
 import de.labystudio.spotifyapi.platform.windows.api.playback.PlaybackAccessor;
 import de.labystudio.spotifyapi.platform.windows.api.spotify.SpotifyTitle;
 import de.labystudio.spotifyapi.SpotifyListener;
@@ -148,6 +150,21 @@ public boolean hasPosition() {
         return this.positionKnown;
     }
 
+    @Override
+    public void pressMediaKey(MediaKey mediaKey) {
+        switch (mediaKey) {
+            case NEXT:
+                this.process.pressKey(WinApi.VK_MEDIA_NEXT_TRACK);
+                break;
+            case PREV:
+                this.process.pressKey(WinApi.VK_MEDIA_PREV_TRACK);
+                break;
+            case PLAY_PAUSE:
+                this.process.pressKey(WinApi.VK_MEDIA_PLAY_PAUSE);
+                break;
+        }
+    }
+
     @Override
     public boolean isPlaying() {
         return this.isPlaying;

src/main/java/de/labystudio/spotifyapi/platform/windows/api/WinApi.java

@@ -2,11 +2,13 @@
 
 import com.sun.jna.Native;
 import com.sun.jna.Pointer;
+import com.sun.jna.platform.win32.BaseTSD;
 import com.sun.jna.platform.win32.Kernel32;
 import com.sun.jna.platform.win32.Tlhelp32;
 import com.sun.jna.platform.win32.User32;
 import com.sun.jna.platform.win32.WinDef;
 import com.sun.jna.platform.win32.WinNT;
+import com.sun.jna.platform.win32.WinUser;
 import com.sun.jna.ptr.IntByReference;
 
 import java.util.ArrayList;
@@ -27,6 +29,14 @@ public interface WinApi {
     int PROCESS_VM_WRITE = 0x0020;
     int PROCESS_VM_OPERATION = 0x0008;
 
+    int VK_VOLUME_MUTE = 0xAD;
+    int VK_VOLUME_DOWN = 0xAE;
+    int VK_VOLUME_UP = 0xAF;
+    int VK_MEDIA_NEXT_TRACK = 0xB0;
+    int VK_MEDIA_PREV_TRACK = 0xB1;
+    int VK_MEDIA_STOP = 0xB2;
+    int VK_MEDIA_PLAY_PAUSE = 0xB3;
+
     default int getProcessIdByName(String exeName) {
         Kernel32 kernel = Kernel32.INSTANCE;
 
@@ -137,4 +147,24 @@ default long getModuleAddress(long pid, String moduleName) {
         Kernel32.INSTANCE.CloseHandle(snapshot);
         return -1;
     }
+
+    default void pressKey(int keyCode) {
+        WinUser.INPUT input = new WinUser.INPUT();
+
+        input.type = new WinDef.DWORD(WinUser.INPUT.INPUT_KEYBOARD);
+        input.input.setType("ki");
+        input.input.ki.wVk = new WinDef.WORD(keyCode); // Key code
+        input.input.ki.wScan = new WinDef.WORD(0); // Hardware scan code
+        input.input.ki.time = new WinDef.DWORD(0); // Timestamp (System default)
+        input.input.ki.dwExtraInfo = new BaseTSD.ULONG_PTR(0);
+
+        // Press the key
+        input.input.ki.dwFlags = new WinDef.DWORD(0);  // Key down
+        User32.INSTANCE.SendInput(new WinDef.DWORD(1), new WinUser.INPUT[]{input}, input.size());
+
+        // Release the key
+        input.input.ki.dwFlags = new WinDef.DWORD(2);  // Key up
+        User32.INSTANCE.SendInput(new WinDef.DWORD(1), new WinUser.INPUT[]{input}, input.size());
+
+    }
 }