package foundation.data.entity;

import foundation.data.meta.field.FieldsRuntime;
import foundation.json.IJSONWriter;

public class EntityNode extends Entity {

	protected EntityNode parent;
	protected EntitySet children;
	protected int level;
	
	
	public EntityNode(FieldsRuntime entityMeta) {
		super(entityMeta);
		children = new EntitySet(entityMeta);
		level = 0;
	}
	
	public EntityNode getParent() {
		return parent;
	}
	
	public EntitySet getChildren() {
		return children;
	}
	
	public int getLevel() {
		return level;
	}

	public void changeParent(EntityNode newParent) throws Exception {
		//1.
		parent.deleteChild(this);
		newParent.addChild(newParent);
		
		//2.
		String parentid = newParent.getString("id");
		set("parent_id", parentid);
	}
	
	private void deleteChild(EntityNode child) {
//		String id = child.getString("id");
		//TODO
	}

	public void addChild(EntityNode child) {
		child.level = level + 1;
		child.parent = this;
		children.append(child);
	}

	public void deleteChildren() {
		children.clear();
	}
	
	public EntityNode getRoot() {
		EntityNode current = this;
		EntityNode parent = current.parent;
		
		while (parent != null) {
			   current = parent;
			   parent = current.parent;
		}
		
		return current;
	}

	public void setSelected() {
		this.selectState = SelectState.CurrentAndChildren;
		
		if (parent != null) {
			parent.setSelected(SelectState.Current); 
		}
	}

	private void setSelected(SelectState state) {
		this.selectState = state;
		
		if (parent != null) {
			parent.setSelected(state); 
		}
	}

	public void writeJSON(IJSONWriter writer, SelectState selectState) {
		writer.beginObject();
		
		//1. node 
		super.writeJSONBody(writer);
		writer.write("level", level);
		
		//2. children
		if (children.isEmpty()) {
			writer.writeNull("children");
			writer.endObject();
			return;
		}
		
		writer.beginArray("children");
		for (Entity entity: children) {
			EntityNode child = (EntityNode)entity;
			
			if (SelectState.Current == selectState && (child.selectState == SelectState.Unselect)) {
				continue;
			}

			child.writeJSON(writer, child.selectState);

		}
		writer.endArray();
		
		writer.endObject();
	}

	@Override
	public void writeJSONBody(IJSONWriter writer) {
		super.writeJSONBody(writer);
		
		//1. node 
		writer.write("level", level);
		
		//2. children
		if (!children.isEmpty()) {
			writer.beginArray("children");
			children.writeJSONBody(writer);
			writer.endArray();
		}
	}
}