package frame.variant.translator;

import frame.util.Util;
import frame.variant.ValueType;
import frame.variant.Value;

import java.math.BigDecimal;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;


public class DateTranslator extends ITranslator {

	private static String DefaultFormat = "yyyy-MM-dd HH:mm:ss";
	private DateFormat dateFormat;
			
	public DateTranslator() {
		dateFormat = new SimpleDateFormat(DefaultFormat);
	}
	
	public String toString(Object value) throws Exception {
		if (value == null) {
			return null;
		}
		
		Date date = (Date)value;
		return dateFormat.format(date);
	}
	
	public String toSqlString(Object value) throws Exception {
		if (value == null) {
			return "null";
		}
		
		Date date = toDate(value);
		return Util.quotedStr(dateFormat.format(date));
	}
	
	public String toJSONString(Object value) throws Exception {
		if (value == null) {
			return "null";
		}
		
		Date date = (Date)value;
		return "\"" + dateFormat.format(date) + "\"";
	}
	
	public String toSchemaString(Object value) throws Exception {
		if (value == null) {
			return "";
		}
		
		Date date = (Date)value;
		return "\"" + dateFormat.format(date) + "\"";
	}

	@Override
	public Integer toInteger(Object object) throws Exception {
		throw new Exception("can not translate date (" + object + ") to Integer");
	}

	@Override
	public Double toDouble(Object object) throws Exception {
		throw new Exception("can not translate date (" + object + ") to Double");
	}

	@Override
	public BigDecimal toBigDecimal(Object object) throws Exception {
		throw new Exception("can not translate date (" + object + ") to BigDecimal");
	}
	
	@Override
	public Boolean toBoolean(Object object) throws Exception {
		throw new Exception("can not translate date (" + object + ") to BigDecimal");
	}

	@Override
	public Date toDate(Object object) throws Exception {
		// 只能接受 long(Timestamp)  date string  
		if(object instanceof Long) {
			return new Date((Long)object);
		}
		else if (object instanceof String) {
			Date parsedDate = dateFormat.parse((String) object);
			return parsedDate;
		}
		else if (object instanceof Date) {
			return (Date) object;
		}
		else {
			throw new Exception("can not parse to date");
		}
	
	}

	@Override
	public Object toTranslatorTypeValue(Object value) throws Exception {
		return toDate(value);
	}
	
	@Override
	public Object loadObjectFrom(String value) throws Exception {
		if (Util.isEmptyStr(value)) {
			return null;
		}
		
		return dateFormat.parse(value);
	}
	
	@Override
	public Value loadVariantFrom(String value) throws Exception {
		Object object = loadObjectFrom(value);
		
		Value variant = new Value();
		variant.setData(object, ValueType.Date);
		
		return variant;
	}
	
	@Override
	public Value loadVariantFrom(String value, Object defaultValue) {
		try {
			return loadVariantFrom(value);
		}
		catch (Exception e) {
			Value variant = new Value();
			variant.setData(defaultValue, ValueType.Date);
			return variant;
		}
	}
	
	@Override
	public void setFormat(String format) {
		if (Util.isEmptyStr(format)) {
			format = DefaultFormat;
		}
		
		this.format = format;
		dateFormat = new SimpleDateFormat(format);
	}

	@Override
	public Class<?> getDataClass() {
		return Date.class;
	}
}