package org.warp.jcwdb.ann;

import java.io.IOException;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.LinkedHashMap;
import java.util.Map;

public class DataInitializer {
	private final DataLoader dataLoader;

	public DataInitializer(DataLoader dataLoader) {
		this.dataLoader = dataLoader;
	}

	public void initializeDBObject(DBObject obj) throws IOException {
		initializeDBObjectFields(obj);
		initializeDBObjectProperties(obj);
		obj.initialize();
	}

	private void initializeDBObjectFields(DBObject obj) throws IOException {
		// Declare the variables needed to get the biggest field Id
		Field[] unorderedFields = dataLoader.getFields(obj);
		// Find the biggest field Id
		int biggestFieldId = dataLoader.getBiggestFieldId(unorderedFields);

		// Allocate new UIDs
		long[] fieldUIDs = dataLoader.allocateNewUIDs(biggestFieldId + 1);

		// Declare the other variables
		Field[] fields = new Field[biggestFieldId + 1];
		DBDataType[] orderedFieldTypes = new DBDataType[biggestFieldId + 1];

		// Load all fields metadata and load them
		for (Field field : unorderedFields) {
			DBField fieldAnnotation = field.getAnnotation(DBField.class);
			int fieldId = fieldAnnotation.id();
			DBDataType fieldType = fieldAnnotation.type();
			dataLoader.loadField(obj, field, fieldType, fieldUIDs[fieldId]);
			fields[fieldId] = field;
			orderedFieldTypes[fieldId] = fieldType;
		}
		// Set fields metadata
		obj.setFields(fields, orderedFieldTypes, fieldUIDs);
	}

	private void initializeDBObjectProperties(DBObject obj) {
		// Declare the variables needed to get the biggest property Id
		Method[] unorderedPropertyGetters = obj.getPropertyGetters();
		Method[] unorderedPropertySetters = obj.getPropertySetters();

		// Find the biggest property Id
		int biggestGetter = dataLoader.getBiggestPropertyGetterId(unorderedPropertyGetters);
		int biggestSetter = dataLoader.getBiggestPropertySetterId(unorderedPropertySetters);
		int biggestPropertyId = biggestGetter > biggestSetter ? biggestGetter : biggestSetter;

		// Allocate new UIDs
		long[] propertyUIDs = dataLoader.allocateNewUIDs(biggestPropertyId + 1);

		for (Method property : unorderedPropertySetters) {
			DBPropertySetter fieldAnnotation = property.getAnnotation(DBPropertySetter.class);
			int propertyId = fieldAnnotation.id();
			if (propertyId > biggestPropertyId) {
				biggestPropertyId = propertyId;
			}
		}

		// Declare the other variables
		DBDataType[] propertyTypes = new DBDataType[biggestPropertyId + 1];
		Method[] propertyGetters = new Method[biggestPropertyId + 1];
		Method[] propertySetters = new Method[biggestPropertyId + 1];
		Map<String, DBPropertySetter> setterMethods = new LinkedHashMap<>();
		Map<String, DBPropertyGetter> getterMethods = new LinkedHashMap<>();

		// Load the properties metadata
		for (Method property : unorderedPropertyGetters) {
			DBPropertyGetter propertyAnnotation = property.getAnnotation(DBPropertyGetter.class);
			int propertyId = propertyAnnotation.id();
			DBDataType propertyType = propertyAnnotation.type();
			propertyTypes[propertyId] = propertyType;
			propertyGetters[propertyId] = property;
			getterMethods.put(property.getName(), propertyAnnotation);
		}
		for (Method property : unorderedPropertySetters) {
			DBPropertySetter propertyAnnotation = property.getAnnotation(DBPropertySetter.class);
			int propertyId = propertyAnnotation.id();
			DBDataType propertyType = propertyAnnotation.type();
			propertyTypes[propertyId] = propertyType;
			propertySetters[propertyId] = property;
			setterMethods.put(property.getName(), propertyAnnotation);
		}
		// Set properties metadata
		obj.setProperties(propertyGetters, propertySetters, propertyTypes, propertyUIDs, setterMethods, getterMethods);
	}
}