Continuation of commit f0df7fa

src/main/java/net/vhati/ftldat/PackContainer.java

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+package net.vhati.ftldat;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import net.vhati.ftldat.AbstractPack;
+
+
+/**
+ * A container coordinating access to one or more of FTL's dat files.
+ *
+ * FTL 1.01-1.5.13 had two files "data.dat" and "resource.dat", in a
+ * subdirectory "resources/" relative to FTLGame.exe.
+ *   data.dat:data/
+ *   resource.dat:audio/
+ *   resource.dat:fonts/
+ *   resource.dat:img/
+ *
+ * FTL 1.6.1 switched to a single "ftl.dat", alongside "FTLGame.exe".
+ *   ftl.dat:audio/
+ *   ftl.dat:data/
+ *   ftl.dat:fonts/
+ *   ftl.dat:img/
+ *
+ * SlipStream mods may have "mod-appendix/", which should be ignored, not added
+ * to packs.
+ *
+ * @see net.vhati.ftldat.FTLPack
+ * @see net.vhati.ftldat.PkgPack
+ */
+public class PackContainer {
+
+	/**
+	 * Regex for innerPaths.
+	 *
+	 * Group1: parentPath/ (may be null).
+	 * Group2: root/ (may be null).
+	 * Group3: fileName (never null, if innerPath is valid).
+	 */
+	protected Pattern pathPtn = Pattern.compile( "^(?:(([^/]+/)(?:.*/)?))?([^/]+)$" );
+
+	protected Map<String, AbstractPack> rootMap = new HashMap<String, AbstractPack>();
+	protected AbstractPack defaultPack = null;
+
+
+	public PackContainer() {
+	}
+
+	/**
+	 * Sets a pack to use when not overridden for specific root dirs.
+	 *
+	 * If null, only specific root dir paths will be supported.
+	 */
+	public void setDefaultPack( AbstractPack pack ) {
+		defaultPack = pack;
+	}
+
+	public AbstractPack getDefaultPack() {
+		return defaultPack;
+	}
+
+	/**
+	 * Sets a pack to use for innerPaths within a given root dir, instead of
+	 * the default pack.
+	 *
+	 * The root must include a trailing forward slash.
+	 *
+	 * A null pack should be interpreted as the result when paths should be
+	 * ignored. A null root would apply to top-level files.
+	 */
+	public void setPackFor( String root, AbstractPack pack ) throws IllegalArgumentException {
+		if ( root != null && !root.endsWith( "/" ) ) {
+			throw new IllegalArgumentException( "Root dir lacks a trailing forward slash:"+ root );
+		}
+
+		rootMap.put( root, pack );
+	}
+
+	/**
+	 * Returns the pack relevant to innerPath, or null.
+	 *
+	 * Returns null if no pack is relevant or if innerPath is malformed.
+	 */
+	public AbstractPack getPackFor( String innerPath ) {
+		Matcher m = pathPtn.matcher( innerPath );
+		if ( m.matches() ) {
+			String root = m.group( 1 );
+			AbstractPack rootPack = rootMap.get( root );
+
+			if ( rootPack != null ) return rootPack;
+			if ( !rootMap.containsKey( root ) ) return null;
+		}
+		else {
+			return null;  // Malformed.
+		}
+
+		if ( defaultPack != null ) return defaultPack;
+
+		return null;
+	}
+
+	/**
+	 * Returns a list of known root dirs.
+	 *
+	 * The list may contain null, if that root was set.
+	 */
+	public List<String> getRoots() {
+		return new ArrayList<String>( rootMap.keySet() );
+	}
+
+	/**
+	 * Returns a list of all contained packs.
+	 */
+	public List<AbstractPack> getPacks() {
+		List<AbstractPack> result = new ArrayList<AbstractPack>( rootMap.values().size() + 1 );
+
+		for ( AbstractPack pack : rootMap.values() ) {
+			if ( pack != null && !result.contains( pack ) ) result.add( pack );
+		}
+		if ( defaultPack != null ) result.add( defaultPack );
+
+		return result;
+	}
+}