package org.biojava.bio.structure.scop;

import java.util.HashMap;
import java.util.Map;



/**
 * Controls the global ScopDatabase being used.
 * 
 * <p>Defaults to a {@link RemoteScopInstallation}, which is fast for small numbers
 * of queries. For many queries, using {@link #getSCOP(String, boolean) getSCOP(version,true)}
 * may be faster, since it makes only one network request.
 * 
 * <p>Example: Fetch the structure corresponding to an old version of scop
 * 
 * <pre>
 * ScopInstallation scop = new ScopInstallation();
 * scop.setScopVersion("1.69");
 * ScopFactory.setScopDatabase(scop);
 * AtomCache cache = new AtomCache();
 * cache.setFetchFileEvenIfObsolete(true); //fetch older PDBs
 * cache.setStrictSCOP(false); // correct simple errors in domain names
 * Structure s = cache.getStructure("d3hbia_");
 * @author sbliven
 *
 */
public class ScopFactory {

	// berkeley 2
	public static final String VERSION_2_0_4 = "2.04";
	public static final String VERSION_2_0_3 = "2.03";
	public static final String VERSION_2_0_2 = "2.02";
	public static final String VERSION_2_0_1 = "2.01";
	// berkeley 1 (aliases of above)
	public static final String VERSION_1_75C = VERSION_2_0_3;
	public static final String VERSION_1_75B = VERSION_2_0_2;
	public static final String VERSION_1_75A = VERSION_2_0_1;
	// original SCOP
	// latest SCOP release from SCOP website = 1.75;
	public static final String VERSION_1_75 = "1.75";
	// outdated stable versions
	public static final String VERSION_1_73 = "1.73";
	public static final String VERSION_1_71 = "1.71";
	public static final String VERSION_1_69 = "1.69";
	public static final String VERSION_1_67 = "1.67";
	public static final String VERSION_1_65 = "1.65";
	public static final String VERSION_1_63 = "1.63";
	public static final String VERSION_1_61 = "1.61";
	public static final String VERSION_1_59 = "1.59";
	public static final String VERSION_1_57 = "1.57";
	public static final String VERSION_1_55 = "1.55";

	// The most recent version as of compilation time
	public static final String LATEST_VERSION = VERSION_2_0_4;

	// Hold one instance for each version
	private static Map<String,ScopDatabase> versionedScopDBs = new HashMap<String, ScopDatabase>(); 
	private static String defaultVersion = LATEST_VERSION;

	/**
	 * Get the current default instance for the default version
	 * @return
	 */
	public static ScopDatabase getSCOP(){
		return getSCOP(defaultVersion);
	}

	/**
	 * 
	 * @param forceLocalData Whether to use a local installation or a remote installation
	 * @return
	 * @see #getSCOP(String, boolean)
	 */
	public static ScopDatabase getSCOP(boolean forceLocalData) {
		return getSCOP(defaultVersion, forceLocalData);
	}

	/**
	 * requests a particular version of SCOP.
	 *
	 * Where possible, this will be the current default instance.
	 * Otherwise a new instance will be created.
	 * @param version
	 * @return
	 */
	public static ScopDatabase getSCOP(String version){
		// Default to a remote installation
		return getSCOP(version,false);
	}

	/**
	 * Gets an instance of the specified scop version.
	 * 
	 * <p>
	 * The particular implementation returned is influenced by the <tt>forceLocalData</tt>
	 * parameter. When false, the instance returned will generally be a
	 * {@link RemoteScopInstallation}, although this may be influenced by
	 * previous calls to this class. When true, the result is guaranteed to
	 * implement {@link LocalScopDatabase} (generally a {@link BerkeleyScopInstallation}).
	 * 
	 * <p>
	 * Note that  
	 * @param version A version number, such as {@link #VERSION_1_75A}
	 * @param forceLocalData Whether to use a local installation or a remote installation
	 * @return an
	 */
	public static ScopDatabase getSCOP(String version, boolean forceLocalData){
		if( version == null ) {
			version = defaultVersion;
		}
		ScopDatabase scop = versionedScopDBs.get(version);
		if ( forceLocalData) {
			// Use a local installation
			if( scop == null || !(scop instanceof LocalScopDatabase) ) {
				BerkeleyScopInstallation berkeley = new BerkeleyScopInstallation();
				berkeley.setScopVersion(version);
				versionedScopDBs.put(version,berkeley);
				return berkeley;
			}
			return scop;
		} else {
			// Use a remote installation
			if( scop == null ) {
				scop = new RemoteScopInstallation();
				scop.setScopVersion(version);
				versionedScopDBs.put(version,scop);
			}
			return scop;
		}
	}


	/**
	 * Set the default scop version
	 * @param version A version number, such as {@link #VERSION_1_75A}
	 */
	public static void setScopDatabase(String version) {
		getSCOP(version);
		defaultVersion = version;
	}
	
	/**
	 * Set the default scop version
	 * @param version A version number, such as {@link #VERSION_1_75A}
	 * @param forceLocalData Whether to use a local installation or a remote installation
	 */
	public static void setScopDatabase(String version, boolean forceLocalData) {
		//System.out.println("ScopFactory: Setting ScopDatabase to version: " + version + " forced local: " + forceLocalData);
		getSCOP(version,forceLocalData);
		defaultVersion = version;
	}

	/**
	 * Set the default scop version and instance
	 * @param scop
	 */
	public static void setScopDatabase(ScopDatabase scop){
		//System.out.println("ScopFactory: Setting ScopDatabase to type: " + scop.getClass().getName());
		defaultVersion = scop.getScopVersion();
		versionedScopDBs.put(defaultVersion,scop);
	}
}
