package nabble.model;

import fschmidt.db.DbDatabase;
import fschmidt.db.DbUtils;
import fschmidt.db.postgres.DbDatabaseImpl;
import fschmidt.db.util.WeakCacheMap;
import fschmidt.util.java.Computable;
import fschmidt.util.java.SimpleCache;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.sql.Connection;
import java.sql.Statement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;


final class SiteKey {
	private static final Logger logger = LoggerFactory.getLogger(SiteKey.class);

	private final long siteId;
	private SiteImpl site = null;
	private SiteGlobal siteGlobal = null;
//	final Object lastNodeLock = new Object();

	private SiteKey(long siteId) {
		this.siteId = siteId;
	}

	public long getId() {
		return siteId;
	}

	SiteImpl site() {
		if( DbUtils.isStale(site) ) {
			try {
				site = SiteImpl.getSite(this,siteId);
			} catch(Db.NoSchema e) {
				site = null;
			}
		}
		return site;
	}

	SiteGlobal siteGlobal() {
		if( DbUtils.isStale(siteGlobal) ) {
			siteGlobal = SiteGlobal.getSiteGlobal(siteId);
		}
		return siteGlobal;
	}

	String schema() {
		return "s" + siteId;
	}

	public DbDatabase getDb() {
		return Db.db(schema());
	}

	@Override public String toString() {
		return "siteKey-"+siteId;
	}

	private static Computable<Long,SiteKey> cache = new SimpleCache<Long,SiteKey>(new WeakCacheMap<Long,SiteKey>(), new Computable<Long,SiteKey>() {
		public SiteKey get(Long siteId) {
			return new SiteKey(siteId);
		}
	});

	static SiteKey getInstance(long siteId) {
		return cache.get(siteId);
	}

	static List<SiteKey> getSiteKeys(String task) throws SQLException {
		List<SiteKey> list = new ArrayList<SiteKey>();
		Connection con = Db.dbGlobal().getConnection();
		PreparedStatement stmt = con.prepareStatement(
			"select * from task where task = ?"
			, ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE
		);
		stmt.setString(1,task);
		ResultSet rs = stmt.executeQuery();
		while( rs.next() ) {
			list.add( getInstance( rs.getLong("site_id") ) );
			rs.deleteRow();
		}
		rs.close();
		stmt.close();
		con.close();
		return list;
	}

	void addTask(String task) {
		try {
			Connection con = Db.dbGlobal().getConnection();
			try {
				PreparedStatement stmt = con.prepareStatement(
					"insert into task (site_id,task) values (?,?)"
				);
				stmt.setLong( 1, getId() );
				stmt.setString( 2, task );
				DbDatabaseImpl.executeUpdateIgnoringDuplicateKeys(stmt);
				stmt.close();
			} finally {
				con.close();
			}
		} catch(SQLException e) {
			throw new RuntimeException(e);
		}
	}

	static List<SiteKey> getAllSiteKeys() {
		try {
			List<SiteKey> list = new ArrayList<SiteKey>();
			Connection con = Db.dbGlobal().getConnection();
			Statement stmt = con.createStatement();
			ResultSet rs = stmt.executeQuery(
				"select site_id from site_global"
			);
			while( rs.next() ) {
				list.add( getInstance( rs.getLong("site_id") ) );
			}
			rs.close();
			stmt.close();
			con.close();
			return list;
		} catch(SQLException e) {
			throw new RuntimeException(e);
		}
	}

}