package foundation.data.object;

import java.util.Set;

import foundation.data.meta.field.FieldsRuntime;
import foundation.util.CaseInsensitiveSet;
import foundation.util.ContentBuilder;
import foundation.variant.provider.DataEvent;
import foundation.variant.provider.IVariantsProvider;
import foundation.variant.provider.VariantProviderType;

public class DataObjectVariantsProvider implements IVariantsProvider {

	private static Set<String> names;
	private DataObject dataObject;
	
	static {
		init();
	}
	
	public DataObjectVariantsProvider(DataObject dataObject) {
		this.dataObject = dataObject;
	}
	
	@Override
	public String getProviderName() {
		return DataObject.class.getSimpleName();
	}

	@Override
	public VariantProviderType getProviderType() {
		return VariantProviderType.Persist;
	}

	public boolean containsVariant(String name) {
		return names.contains(name);
	}

	@Override
	public Object getVariantValue(DataEvent dataEvent, String name) {
		if (name == null) {
			return null;
		}
		
		name = name.toLowerCase();
		
		try {
			if ("tablename".equals(name)) {
				return dataObject.getTableName();
			}
			else if ("fieldnames".equals(name)) {
				FieldsRuntime fieldsRuntime = dataObject.getTableFieldMetas();
				int size = fieldsRuntime.getFieldCount();
				String[] fieldNames = fieldsRuntime.getFieldNames();
				
				ContentBuilder builder = new ContentBuilder(", ");
				
				for (int i = 0; i < size; i++) {
					builder.append(fieldNames[i]);
				}
				
				return builder.toString();
			}
			else if ("placeholders".equals(name)) {
				FieldsRuntime fieldsRuntime = dataObject.getTableFieldMetas();
				int size = fieldsRuntime.getFieldCount();
				
				ContentBuilder builder = new ContentBuilder(", ");
				
				for (int i = 0; i < size; i++) {
					builder.append("?");
				}
				
				return builder.toString();
			}
		}
		catch (Exception e) {
		}

		return null;
	}

	@Override
	public Set<String> getVariantNames() {
		return names;
	}

	private static void init() {
		names = new CaseInsensitiveSet();
		names.add("tablename");
		names.add("fieldNames");
		names.add("placeHolders");
	}

}