Sanity checks

src/main/java/featurecat/lizzie/Lizzie.java

@@ -5,9 +5,12 @@
 import featurecat.lizzie.plugin.PluginManager;
 import featurecat.lizzie.rules.Board;
 import featurecat.lizzie.gui.LizzieFrame;
+import org.json.JSONObject;
 
 import javax.swing.*;
+import java.io.File;
 import java.io.IOException;
+import java.util.ResourceBundle;
 
 /**
  * Main class.
@@ -27,6 +30,21 @@ public static void main(String[] args) throws IOException, JSONException, ClassN
 
         config = new Config();
 
+        // Check that user has installed leela zero
+        JSONObject leelazconfig = Lizzie.config.config.getJSONObject("leelaz");
+        ResourceBundle resourceBundle = ResourceBundle.getBundle("l10n.DisplayStrings");
+        String startfolder = leelazconfig.optString("engine-start-location", ".");
+
+        // Check if engine is present
+        File lef = new File(startfolder + '/' + "leelaz");
+        if (!lef.exists()) {
+            File leexe = new File(startfolder + '/' + "leelaz.exe");
+            if (!leexe.exists()) {
+                JOptionPane.showMessageDialog(null, resourceBundle.getString("LizzieFrame.display.leelaz-missing"), "Lizzie - Error!", JOptionPane.ERROR_MESSAGE);
+                return;
+            }
+        }
+
         PluginManager.loadPlugins();
 
         board = new Board();

src/main/java/featurecat/lizzie/analysis/Leelaz.java

@@ -82,6 +82,15 @@ public Leelaz() throws IOException, JSONException {
             updateToLatestNetwork();
         }
 
+        String startfolder = config.optString("engine-start-location", ".");
+
+        // Check if network file is present
+        File wf = new File(startfolder + '/' + config.getString("network-file"));
+        if (!wf.exists()) {
+            JOptionPane.showMessageDialog(null, resourceBundle.getString("LizzieFrame.display.network-missing"));
+        }
+
+
         // command string for starting the engine
         String engineCommand = config.getString("engine-command");
         // substitute in the weights file
@@ -91,7 +100,7 @@ public Leelaz() throws IOException, JSONException {
 
         // run leelaz
         ProcessBuilder processBuilder = new ProcessBuilder(commands);
-        processBuilder.directory(new File(config.optString("engine-start-location", ".")));
+        processBuilder.directory(new File(startfolder));
         processBuilder.redirectErrorStream(true);
         process = processBuilder.start();
 

src/main/resources/l10n/DisplayStrings.properties

@@ -48,4 +48,6 @@ LizzieFrame.display.pondering=Pondering
 LizzieFrame.display.on=on
 LizzieFrame.display.off=off
 LizzieFrame.display.loading=Leela Zero is loading...
-LizzieFrame.display.download-latest-network-prompt=Download the latest network file? This may take some time.
+LizzieFrame.display.download-latest-network-prompt=Download the latest network file? This may take some time.
+LizzieFrame.display.leelaz-missing=Did not find Leela Zero, update config.txt or download from Leela Zero homepage
+LizzieFrame.display.network-missing=Did not find network/weights.\nUpdate config.txt (network-file) or download from Leela Zero homepage

src/main/resources/l10n/DisplayStrings_zh_CN.properties

@@ -37,3 +37,5 @@ LizzieFrame.display.on=\u5F00\u542F
 LizzieFrame.display.off=\u6682\u505C
 LizzieFrame.display.loading=Leela Zero\u6B63\u5728\u8F7D\u5165\u4E2D...
 LizzieFrame.display.download-latest-network-prompt=Download the latest network file? This may take some time.
+LizzieFrame.display.leelaz-missing=Did not find Leela Zero, update config.txt or download from Leela Zero homepage
+LizzieFrame.display.network-missing=Did not find network/weights.\nUpdate config.txt (network-file) or download from Leela Zero homepage