From 1afda36d85e01a2f774d8743dd0aff7c228b0a84 Mon Sep 17 00:00:00 2001
From: Peter Osterlund <peterosterlund2@gmail.com>
Date: Fri, 3 Jan 2020 10:32:49 +0100
Subject: [PATCH] Don't try to fixup invalid e.p. square if the position is
 invalid

En passant fixup requires generating a list of legal moves, which can
fail with an array index out of bounds exception if there is a pawn on
the first/last rank.
---
 .../org/petero/droidfish/activities/EditBoard.java  | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/activities/EditBoard.java b/DroidFishApp/src/main/java/org/petero/droidfish/activities/EditBoard.java
index a7f0e0e..f1df5d5 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/activities/EditBoard.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/activities/EditBoard.java
@@ -442,7 +442,8 @@ public class EditBoard extends Activity {
 
     private void setPosFields() {
         setEPFile(getEPFile()); // To handle sideToMove change
-        TextIO.fixupEPSquare(cb.pos);
+        if (isValid())
+            TextIO.fixupEPSquare(cb.pos);
         TextIO.removeBogusCastleFlags(cb.pos);
     }
 
@@ -478,6 +479,16 @@ public class EditBoard extends Activity {
         return false;
     }
 
+    /** Return true if the position is valid. */
+    private boolean isValid() {
+        try {
+            TextIO.readFEN(TextIO.toFEN(cb.pos));
+            return true;
+        } catch (ChessParseError e) {
+            return false;
+        }
+    }
+
     private String getParseErrString(ChessParseError e) {
         if (e.resourceId == -1)
             return e.getMessage();