From 4e1682ac16889c85952c6f7f496668d564b7e284 Mon Sep 17 00:00:00 2001
From: kske <kai@kske.dev>
Date: Wed, 9 Oct 2019 21:03:39 +0200
Subject: [PATCH] Added PGNDatabase and PGNGame classes with support for PGN
 parsing

---
 src/dev/kske/chess/pgn/PGNDatabase.java | 29 ++++++++++
 src/dev/kske/chess/pgn/PGNGame.java     | 77 +++++++++++++++++++++++++
 2 files changed, 106 insertions(+)
 create mode 100644 src/dev/kske/chess/pgn/PGNDatabase.java
 create mode 100644 src/dev/kske/chess/pgn/PGNGame.java

diff --git a/src/dev/kske/chess/pgn/PGNDatabase.java b/src/dev/kske/chess/pgn/PGNDatabase.java
new file mode 100644
index 0000000..61ccdc6
--- /dev/null
+++ b/src/dev/kske/chess/pgn/PGNDatabase.java
@@ -0,0 +1,29 @@
+package dev.kske.chess.pgn;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Scanner;
+
+import dev.kske.chess.exception.ChessException;
+
+/**
+ * Project: <strong>Chess</strong><br>
+ * File: <strong>PGNDatabase.java</strong><br>
+ * Created: <strong>4 Oct 2019</strong><br>
+ * Author: <strong>Kai S. K. Engelbart</strong>
+ */
+public class PGNDatabase {
+
+	private final List<PGNGame>	games	= new ArrayList<>();
+
+	public void load(File pgnFile) {
+		try (Scanner sc = new Scanner(pgnFile)) {
+			while (sc.hasNext())
+				games.add(PGNGame.parse(sc));
+		} catch (FileNotFoundException | ChessException e) {
+			e.printStackTrace();
+		}
+	}
+}
diff --git a/src/dev/kske/chess/pgn/PGNGame.java b/src/dev/kske/chess/pgn/PGNGame.java
new file mode 100644
index 0000000..e800a3c
--- /dev/null
+++ b/src/dev/kske/chess/pgn/PGNGame.java
@@ -0,0 +1,77 @@
+package dev.kske.chess.pgn;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Scanner;
+import java.util.regex.MatchResult;
+import java.util.regex.Pattern;
+
+import dev.kske.chess.board.Board;
+import dev.kske.chess.exception.ChessException;
+
+/**
+ * Project: <strong>Chess</strong><br>
+ * File: <strong>PGNGame.java</strong><br>
+ * Created: <strong>22 Sep 2019</strong><br>
+ * Author: <strong>Kai S. K. Engelbart</strong>
+ */
+public class PGNGame {
+
+	private final Map<String, String>	tagPairs	= new HashMap<>(7);
+	private final Board					board		= new Board();
+
+	public static PGNGame parse(Scanner sc) throws ChessException {
+		PGNGame game = new PGNGame();
+
+		MatchResult	matchResult;
+		Pattern		tagPairPattern	= Pattern.compile("\\[(\\w+) \"(.*)\"]"),
+				movePattern = Pattern.compile("\\d+\\. (\\S+)\\s(\\S+)"),
+				nagPattern = Pattern.compile("(\\$\\d{1,3})*"),
+				terminationMarkerPattern = Pattern.compile("1-0|0-1|1\\/2-1\\/2|\\*");
+
+		// Parse tag pairs
+		while (true) {
+			if (sc.findInLine(tagPairPattern) != null) {
+				matchResult = sc.match();
+				if (matchResult.groupCount() == 2) game.setTag(matchResult.group(0), matchResult.group(1));
+				else break;
+			} else break;
+			sc.nextLine();
+		}
+
+		// Parse movetext
+		while (true) {
+			// Skip NAG (Numeric Annotation Glyph)
+			sc.skip(nagPattern);
+
+			// TODO: Parse RAV (Recursive Annotation Variation)
+
+			sc.findWithinHorizon(movePattern, 20);
+			matchResult = sc.match();
+			if (matchResult.groupCount() > 0) for (int i = 1; i < matchResult.groupCount() + 1; i++) {
+				game.board.move(matchResult.group(i));
+				System.out.println(game.board.toFEN());
+			}
+			else break;
+		}
+
+		// Parse game termination marker
+		if (sc.hasNext(terminationMarkerPattern)) {
+			sc.next(terminationMarkerPattern);
+		} else throw new ChessException("Game termination marker expected");
+
+		return game;
+	}
+
+	public String getTag(String tagName) {
+		return tagPairs.get(tagName);
+	}
+
+	public boolean hasTag(String tagName) {
+		return tagPairs.containsKey(tagName);
+	}
+
+	public void setTag(String tagName, String tagValue) {
+		tagPairs.put(tagName, tagValue);
+	}
+}