package pt.ist.fenixWebFramework.rendererExtensions;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import pt.ist.fenixWebFramework.util.DomainListReference;
import pt.ist.fenixWebFramework.util.DomainReference;
import pt.ist.fenixframework.DomainObject;

public class PageContainerBean implements Serializable {
    
    private transient List<? extends DomainObject> objects;
    private DomainListReference<DomainObject> pageObjects;
    private DomainReference<DomainObject> selected;
    private Integer numberOfPages;
    
    private Integer page = 1;
    
    public List<? extends DomainObject> getObjects() {
        return objects;
    }

    public void setObjects(List<? extends DomainObject> objects) {
	this.objects = objects;
        setPageObjects(null);
    }
    
    public List<DomainObject> getPageObjects() {
	if(this.pageObjects != null) {
	    List<DomainObject> result = new ArrayList<DomainObject>();
	    for (DomainObject domainObject : this.pageObjects) {
		result.add(domainObject);
	    }
	    return result;
	} else {
	    return null;
	}
    }

    public void setPageObjects(List<? extends DomainObject> pageObjects) {
	if(pageObjects != null) {
	    this.pageObjects = new DomainListReference<DomainObject>();
	    for (DomainObject object : pageObjects) {
		this.pageObjects.add(object);
	    }
	} else {
	    this.pageObjects = null;
	}
    }

    public Integer getPage() {
        return page;
    }

    public void setPage(Integer page) {
        this.page = page;
    }
    
    public DomainObject getSelected() {
	return (this.selected != null) ? this.selected.getObject() : null;
    }

    public void setSelected(DomainObject selected) {
	this.selected = (selected != null) ? new DomainReference<DomainObject>(selected) : null;
    }
    
    public List<DomainObject> getPageByPageSize(int pageSize){
	if(getPageObjects() != null) {
	    return getPageObjects();
	} else {
	    if(getObjects() != null && !getObjects().isEmpty()) {
		validatePageNumber(pageSize);
		int from = (getPage() - 1)  * pageSize;
		int to = getObjects().size() > getPage() * pageSize ? getPage() * pageSize : getObjects().size();
		List<DomainObject> subList = new ArrayList<DomainObject>(getObjects().subList(from, to));
		setPageObjects(subList);
		return subList;
	    } else {
		return Collections.emptyList();
	    }
	}
    }
    
    private void validatePageNumber(int pageSize) {
	if(getPage() < 1) {
	    setPage(1);
	} else {
	    Integer numberOfPages = getNumberOfPages(pageSize);
	    if(getPage() > numberOfPages) {
		setPage(numberOfPages);
	    }
	}
	
    }

    public int getNumberOfPages(int pageSize) {
	if(getObjects() != null) {
	    this.numberOfPages = (int) Math.ceil((double) getObjects().size() / pageSize);
	}
	return this.numberOfPages;
    }
    
    public boolean hasNextPage(int pageSize) {
	return getPage() < getNumberOfPages(pageSize);
    }
    
    public boolean hasPreviousPage(int pageSize) {
	return getPage() > 1; 
    }

    public List<? extends DomainObject> getAllObjects() {
	if(getPageObjects() != null) {
	    return getPageObjects();
	} else {
	    if(getObjects() != null) {
		setPageObjects(getObjects());
		return getObjects();
	    } else {
		return Collections.emptyList();
	    }
	} 
    }
    
    public void setPageJump(Integer pageJump) {
	setPage(pageJump);
    }
    
    public Integer getPageJump() {
	return null;
    }

}