package foundation.data.object;

import java.util.Date;
import java.util.Iterator;

import foundation.data.meta.field.FieldsRuntime;
import foundation.util.ContentBuilder;
import foundation.util.MapList;
import foundation.util.Util;

public class DataJoins implements Iterable<DataJoin> {

	private MapList<String, DataJoin> items;
	private String commaSeparator;
	private String joinSelectFields;
	private String joinSQL;
	private String[] joinTables;
	private boolean builded;
	private Date lastUpdateTime;

	
	public DataJoins() {
		items = new MapList<String, DataJoin>();
		builded = false;
		lastUpdateTime = new Date(0);
		joinTables = null;
	}

	public void loadOne(DataJoin dataJoin) {
		//1.
		items.add(dataJoin.getJoinDataName(), dataJoin);
		
		//2. 
		Date time = dataJoin.getUpdateTime();
		lastUpdateTime = lastUpdateTime.after(time) ? lastUpdateTime : time;
	}

	public void build() throws Exception {
		if (builded) {
			return;
		}
		
		//1. 
		for (DataJoin dataJoin: items) {
			dataJoin.build();
		}
		
		//2. build join select fields
		ContentBuilder joinFieldsBuilder = new ContentBuilder(", ");
		
		for (DataJoin dataJoin: items) {
			dataJoin.getJoinFields(joinFieldsBuilder);
		}
		
		joinSelectFields = joinFieldsBuilder.toString();
		
		//3. build join SQL
		ContentBuilder joinSQLBuilder = new ContentBuilder(Util.String_Return);
		
		for (DataJoin dataJoin: items) {
			joinSQLBuilder.append(dataJoin.getJoinSQL());
		}
		
		joinSQL = joinSQLBuilder.toString();
		
		//4. build commaSeparator
		commaSeparator = !Util.isEmpty(joinSelectFields) ? ", " : "";
		
		//5.
		int max = items.size();
		joinTables = new String[max];
		
		for (int i = 0; i < max; i++) {
			DataJoin dataJoin = items.get(i);
			joinTables[i] = dataJoin.getJoinDataName();
		}
		
		//6.
		builded = true;
	}

	public FieldsRuntime getJoinFieldsMeta(String tableName) {
		DataJoin dataJoin = items.get(tableName);
		
		if (dataJoin == null) {
			return null;
		}
		
		return dataJoin.getJoinFieldsMeta();
	}
	
	@Override
	public Iterator<DataJoin> iterator() {
		return items.iterator();
	}

	public String getCommaSeparator() {
		return commaSeparator;
	}

	public String getJoinSelectFields() {
		return joinSelectFields;
	}

	public String getJoinSQL() {
		return joinSQL;
	}

	public boolean isEmpty() {
		return items.isEmpty();
	}
	
	public String[] getJoinTables() {
		return joinTables;
	}

	public Date getLastUpdateTime() {
		return lastUpdateTime;
	}

	public int size() {
		return items.size();
	}

	
}