diff -r 3fa1de896666 -r 0c50aac49e55 src/chess/pgn.c
--- a/src/chess/pgn.c	Tue Aug 28 14:16:30 2018 +0200
+++ b/src/chess/pgn.c	Tue Aug 28 14:37:09 2018 +0200
@@ -32,6 +32,27 @@
 #include <stdlib.h>
 #include <string.h>
 
+enum {
+    pgn_error_missing_quote = 1,
+    pgn_error_missing_bracket,
+    pgn_error_missing_dot,
+    pgn_error_move_syntax,
+    pgn_error_move_semantics
+};
+
+static const char* pgn_error_strings[] = {
+    "No Error.",
+    "Tag values must be enclosed in double-quotes.",
+    "Tags must be enclosed in square brackets: '[Key \"Value\"]'.",
+    "Move numbers must be terminated with a dot (e.g. '13.' - not '13').",
+    "Move is syntactically incorrect.",
+    "Move is not valid according to chess rules."
+};
+
+const char* pgn_error_str(int code) {
+    return pgn_error_strings[code];
+}
+
 int read_pgn(FILE* stream, GameState *gamestate, GameInfo *gameinfo) {
     int c, i;
     
@@ -49,7 +70,7 @@
             break;
         }
         if (c != '[') {
-            return 1;
+            return pgn_error_missing_bracket;
         }
         while (isspace(c = fgetc(stream)));
         i = 0;
@@ -59,18 +80,18 @@
         tagkey[i] = '\0';
         while (isspace(c = fgetc(stream)));
         if (c != '"') {
-            return 1;
+            return pgn_error_missing_quote;
         }
         i = 0;
         while ((c = fgetc(stream)) != '"') {
-            if (c == '\n') {
-                return 1;
+            if (c == '\n' || c == EOF) {
+                return pgn_error_missing_quote;
             }
             tagvalue[i++] = c;
         }
         tagvalue[i] = '\0';
         if (fgetc(stream) != ']') {
-            return 1;
+            return pgn_error_missing_bracket;
         }
 
         if (strcmp("Result", tagkey) == 0) {
@@ -80,7 +101,7 @@
     
     // read moves
     if (fgetc(stream) != '.') {
-        return 1;
+        return pgn_error_missing_dot;
     }
     
     char movestr[10];
@@ -100,10 +121,10 @@
         movestr[i] = '\0';
         if (eval_move(gamestate, movestr, &move, curcol)
                 != VALID_MOVE_SYNTAX) {
-            return 1;
+            return pgn_error_move_syntax;
         }
         if (validate_move(gamestate, &move) != VALID_MOVE_SEMANTICS) {
-            return 1;
+            return pgn_error_move_semantics;
         }
         apply_move(gamestate, &move);
         
@@ -135,7 +156,7 @@
         if (curcol == BLACK) {
             while (isdigit(c = fgetc(stream)));
             if (c != '.') {
-                return 1;
+                return pgn_error_missing_dot;
             }
         }
         curcol = opponent_color(curcol);