<?php

/**
 * Classe de paginação para o ERP iBilling.
 *
 * @author Cleberson Falk <cleberson.falk@gmail.com>
 */
class ModulePaginator
{
	private $table;
	private $query;
	protected $params;
	public $items_per_page = 20;
	public $current_page = 0;
	public $total_items = 0;
	public $total_pages = 0;
	public $paginator;
	public $visible_pages = 9;

	/**
	 * Método constructor. Recebe o nome da tabela que será paginada,
	 * a query que será usada na paginação e os parâmetros que serão
	 * passados para url.
	 *
	 * @param $table
	 * @param $query
	 * @param array $params
	 */
	public function __construct($table, $query, $params = array())
	{
		$this->table = $table;
		$this->query = $query;
		if(count($params) > 0)
			$this->params = $params;
	}

	/**
	 * Retorna a quantidade de registros por página
	 * @return int
	 */
	public function getItemsPerPage()
	{
		return $this->items_per_page;
	}

	/**
	 * Seta a quantidade de registros por página.
	 *
	 * @param $items_per_page
	 * @return $this
	 */
	public function setItemsPerPage($items_per_page)
	{
		$this->items_per_page = $items_per_page;
		return $this;
	}

	/**
	 * Retorna a página atual.
	 *
	 * @return int
	 */
	public function getCurrentPageNumber()
	{
		return $this->current_page;
	}

	/**
	 * Seta a página atual.
	 *
	 * @param $page
	 * @return $this
	 */
	public function setCurrentPageNumber($page)
	{
		$this->current_page = ($page <= 0) ? 1 : $page;
		return $this;
	}

	/**
	 * Acrescenta os parâmetros no final da url informada.
	 *
	 * @param $base_url
	 * @param $page
	 * @return string
	 */
	public function url($base_url, $page)
	{
		$url = $base_url . $page . '/';

		if(is_array($this->params) && (count($this->params) > 0)) {
			foreach($this->params as $param => $value) {
				if($value != '')
					$url .= $param .'/'. $value .'/';
			}
		}

		return $url;
	}

	/**
	 * Monta o Html com os links da paginação.
	 *
	 * @param $base_url
	 * @return string
	 */
	public function paginate($base_url)
	{
		global $_L;

		if($this->total_pages > 1) {
			// Ir para primeira página
			$li_first = '<li><a href="' .$this->url($base_url, 1). '"><i class="fa fa-fast-backward pg-arrow"></i></a></li>';

			// Monta o link anterior
			$li_previous = "";
			if($this->current_page > 1)
				$li_previous .= '<li><a href="' .$this->url($base_url, $this->current_page-1). '"><i class="fa fa-backward pg-arrow"></i></a></li>';
			else if($this->current_page <= 1)
				$li_previous .= '<li class="disabled"><a href="#"><i class="fa fa-backward pg-arrow"></i></a></li>';

			$li_pages = "";
			$min = max(1, $this->current_page - floor($this->visible_pages / 2));
			$max = min($this->total_pages, ($this->current_page + floor($this->visible_pages / 2)));

			for($pag = $min; $pag <= $max; $pag++) {
				$li_pages .= '<li' .(($this->current_page == $pag) ? ' class="active"' : ''). '><a href="' .$this->url($base_url, $pag). '">' .$pag. '</a></li>';
			}
			
			// Monta o link do próximo
			$li_next = "";
			if($this->current_page < $this->total_pages)
				$li_next = '<li><a href="' .$this->url($base_url, $this->current_page+1). '"><i class="fa fa-forward pg-arrow"></i></a></li>';
			else if($this->current_page >= $this->total_pages)
				$li_next = '<li class="disabled"><a href="#"><i class="fa fa-forward pg-arrow"></i></a></li>';

			// Ir para primeira página
			$li_last = '<li><a href="' .$this->url($base_url, $this->total_pages). '"><i class="fa fa-fast-forward pg-arrow"></i></a></li>';

			return $li_first . $li_previous . $li_pages . $li_next . $li_last;
		}
	}

	/**
	 * Método principal que faz a paginação, executa a query
	 * e retorna um array com os dados da página atual.
	 *
	 * @return array
	 */
	public function run()
	{
		$result_total = ORM::for_table($this->table)
			->raw_query($this->query)->find_array();

		$items_per_page = $this->getItemsPerPage();
		$this->total_items = count($result_total);

		if($items_per_page == 'all')
			$this->total_pages = 1;
		else
			$this->total_pages = ceil($this->total_items / $items_per_page);


		if($items_per_page == 'all') {
			$this->paginator = ORM::for_table($this->table)
				->raw_query($this->query)->find_array();
		}
		else {
			$this->paginator = ORM::for_table($this->table)
				->raw_query(
					$this->query.
					" LIMIT " . (int) $items_per_page .
					" OFFSET " . (int) (($this->getCurrentPageNumber() - 1) * $items_per_page)
				)
				->find_array();
		}

		return $this->paginator;
	}
}