[LIB-9] Set of entities for PGN parsing and formatting

[chesshog.git] / chesshog-format / src / main / java / org / hedgecode / chess / pgn / token / Tokenizer.java

diff --git a/chesshog-format/src/main/java/org/hedgecode/chess/pgn/token/Tokenizer.java b/chesshog-format/src/main/java/org/hedgecode/chess/pgn/token/Tokenizer.java
new file mode 100644 (file)
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+++ b/chesshog-format/src/main/java/org/hedgecode/chess/pgn/token/Tokenizer.java
@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2018-2020. Developed by Hedgecode.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.hedgecode.chess.pgn.token;
+
+import java.util.regex.Pattern;
+
+import org.hedgecode.chess.pgn.entity.Game;
+import org.hedgecode.chess.position.ParseException;
+
+/**
+ * Tokenizer
+ *
+ * @author Dmitry Samoshin aka gotty
+ */
+public class Tokenizer {
+
+    enum Type {
+
+        TAG   ( new TagToken()   ),
+        EMPTY ( new EmptyToken() ),
+        MOVES ( new MovesToken() );
+
+        private Token<Game> token;
+
+        public Token<Game> token() {
+            return token;
+        }
+
+        Type(Token<Game> token) {
+            this.token = token;
+        }
+    }
+
+    private static final Pattern TAG_PATTERN = Pattern.compile("^\\[[^]]+\\]$", Pattern.MULTILINE);
+    private static final Pattern EMPTY_PATTERN = Pattern.compile("^\\s*$", Pattern.MULTILINE);
+    private static final Pattern MOVES_PATTERN = Pattern.compile("^\\s*([^\\s])", Pattern.MULTILINE);
+
+    private final String pgn;
+
+    private Token<Game> token;
+    private String tokenPgn;
+
+    public Tokenizer(String pgn) {
+        this.pgn = pgn;
+        this.tokenPgn = pgn;
+    }
+
+    public boolean hasToken() {
+        assignToken();
+        return token != null;
+    }
+
+    public void token(Game game) throws ParseException {
+        if (token == null) {
+            throw new ParseException("parse.pgn.null.token");
+        }
+        int index = token.token(game, tokenPgn);
+        tokenPgn = tokenPgn.substring(index);
+        token = null;
+    }
+
+    public String sourcePgn() {
+        return pgn;
+    }
+
+    private void assignToken() {
+        token = null;
+        if (!tokenPgn.isEmpty()) {
+            if (TAG_PATTERN.matcher(tokenPgn).find()) {
+                token = Type.TAG.token();
+            } else if (EMPTY_PATTERN.matcher(tokenPgn).find()) {
+                token = Type.EMPTY.token();
+            } else if (MOVES_PATTERN.matcher(tokenPgn).find()) {
+                token = Type.MOVES.token();
+            }
+        }
+    }
+
+}