package tudelft.dialogmanager;

import static org.junit.Assert.assertEquals;

import java.io.IOException;
import java.util.Arrays;
import java.util.List;

import org.junit.Before;
import org.junit.Test;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

import tudelft.dialogmanager.parameters.DoubleValue;
import tudelft.dialogmanager.parameters.ParameterValue;

public class UpdateFunctionTest {

	private final ObjectMapper jackson = new ObjectMapper();
	private final String serialized = "{\"AddFunction\":[[\"a\",\"b\"],[\"sum\"]]}";;
	private final AddFunction testf = new AddFunction(
			Arrays.asList(Arrays.asList("a", "b"), Arrays.asList("sum")));

	@Before
	public void before() {
		jackson.registerSubtypes(AddFunction.class);
	}

	@Test
	public void testSerialize() throws JsonProcessingException {

		String text = jackson.writeValueAsString(testf);
		System.out.println(text);

		assertEquals(serialized, text);
	}

	@Test
	public void testDeserialize()
			throws JsonParseException, JsonMappingException, IOException {
		UpdateFunction func = jackson.readValue(serialized,
				UpdateFunction.class);
		assertEquals(testf, func);
	}

	@Test
	public void testFunctionCall() {
		DoubleValue a = new DoubleValue(3d);
		DoubleValue b = new DoubleValue(4d);
		DoubleValue sum = new DoubleValue(7d);
		assertEquals(Arrays.asList(sum), testf.call(Arrays.asList(a, b)));
	}

}

/**
 * Function that computes sum of argumets
 */
class AddFunction extends UpdateFunction {

	@JsonCreator
	public AddFunction(List<List<String>> inout) {
		super(inout);
	}

	@Override
	public List<ParameterValue> call(List<ParameterValue> inargs) {
		Double a = ((DoubleValue) inargs.get(0)).getValue();
		Double b = ((DoubleValue) inargs.get(1)).getValue();
		return Arrays.asList(new DoubleValue(a + b));
	}

}