<?php

class DB_Model extends FHC_Model
{
	protected $dbTable;  // Name of the DB-Table for CI-Insert, -Update, ...
	protected $pk;  // Name of the PrimaryKey for DB-Update, Load, ...
	protected $hasSequence;	// False if this table has a composite primary key that is not using a sequence
							// True if this table has a primary key that uses a sequence
	protected $acl;  // Name of the PrimaryKey for DB-Update, Load, ...
	
	function __construct($dbTable = null, $pk = null, $hasSequence = true)
	{
		parent::__construct();
		$this->dbTable = $dbTable;
		$this->pk = $pk;
		$this->hasSequence = $hasSequence;
		$this->load->database();
		$this->acl = $this->config->item('fhc_acl');
	}

	/** ---------------------------------------------------------------
	 * Insert Data into DB-Table
	 *
	 * @param   array $data  DataArray for Insert
	 * @return  array
	 */
	public function insert($data)
	{
		// Check Class-Attributes
		if (is_null($this->dbTable))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);

		// Check rights
		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 'i'))
			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);

		// DB-INSERT
		if ($this->db->insert($this->dbTable, $data))
		{
			// If the table has a primary key that uses a sequence
			if ($this->hasSequence === true)
			{
				return $this->_success($this->db->insert_id());
			}
			// Avoid to use method insert_id() from CI because it forces to have a sequence
			// and doesn't return the primary key when it's composed by more columns
			else
			{
				$primaryKeysArray = array();

				foreach ($this->pk as $key => $value)
				{
					if (isset($data[$value]))
					{
						$primaryKeysArray[$value] = $data[$value];
					}
				}

				return $this->_success($primaryKeysArray);
			}
		}
		else
			return $this->_error($this->db->error(), FHC_DB_ERROR);
	}

	/** ---------------------------------------------------------------
	 * Replace Data in DB-Table
	 *
	 * @param   array $data  DataArray for Replacement
	 * @return  array
	 */
	public function replace($data)
	{
		// Check Class-Attributes
		if (is_null($this->dbTable))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		
		// Check rights
		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 'ui'))
			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);

		// DB-REPLACE
		if ($this->db->replace($this->dbTable, $data))
			return $this->_success($this->db->insert_id());
		else
			return $this->_error($this->db->error(), FHC_DB_ERROR);
	}

	/** ---------------------------------------------------------------
	 * Update Data in DB-Table
	 *
	 * @param   string $id  PK for DB-Table
	 * @param   array $data  DataArray for Insert
	 * @return  array
	 */
	public function update($id, $data)
	{
		// Check Class-Attributes
		if (is_null($this->dbTable))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		if (is_null($this->pk))
			return $this->_error(lang('fhc_'.FHC_NOPK), FHC_MODEL_ERROR);
		
		// Check rights
		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 'u'))
			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);

		// DB-UPDATE
		// Check for composite Primary Key
		if (is_array($id))
		{
			if (isset($id[0]))
				$this->db->where($this->_arrayMergeIndex($this->pk, $id));
			else
				$this->db->where($id);
		}
		else
			$this->db->where($this->pk, $id);
		if ($this->db->update($this->dbTable, $data))
			return $this->_success($id);
		else
			return $this->_error($this->db->error(), FHC_DB_ERROR);
	}

	/** ---------------------------------------------------------------
	 * Load single data from DB-Table
	 *
	 * @param   string $id  ID (Primary Key) for SELECT ... WHERE
	 * @return  array
	 */
	public function load($id)
	{
		// Check Class-Attributes
		if (is_null($this->dbTable))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		if (is_null($this->pk))
			return $this->_error(lang('fhc_'.FHC_NOPK), FHC_MODEL_ERROR);
		
		
		// Check rights
		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 's'))
			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);

		// DB-SELECT
		// Check for composite Primary Key
		if (is_array($id))
		{
			if (isset($id[0]))
				$result = $this->db->get_where($this->dbTable, $this->_arrayMergeIndex($this->pk, $id));
			else
				$result = $this->db->get_where($this->dbTable, $id);
		}
		else
			$result = $this->db->get_where($this->dbTable, array($this->pk => $id));
		
		if ($result)
			return $this->_success($result->result());
		else
			return $this->_error($this->db->error(), FHC_DB_ERROR);
	}

	/** ---------------------------------------------------------------
	 * Load data from DB-Table with a where clause
	 *
	 * @return  array
	 */
	public function loadWhere($where = null)
	{
		// Check Class-Attributes
		if (is_null($this->dbTable))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		
		// Check rights
		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 's'))
			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);

		// DB-SELECT
		if (is_null($where))
			$result = $this->db->get($this->dbTable);
		else
			$result = $this->db->get_where($this->dbTable, $where);
		if ($result)
			return $this->_success($result->result());
		else
			return $this->_error($this->db->error(), FHC_DB_ERROR);
	}
	
	/** ---------------------------------------------------------------
	 * Load single data from DB-Table
	 *
	 * @param   string $id  ID (Primary Key) for SELECT ... WHERE
	 * @return  array
	 */
	public function loadWhole()
	{
		// Check Class-Attributes
		if (is_null($this->dbTable))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		if (is_null($this->pk))
			return $this->_error(lang('fhc_'.FHC_NOPK), FHC_MODEL_ERROR);
		
		
		// Check rights
		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 's'))
			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);

		// DB-SELECT
		$result = $this->db->get($this->dbTable);
		
		if ($result)
			return $this->_success($result->result());
		else
			return $this->_error($this->db->error(), FHC_DB_ERROR);
	}
	
	/** ---------------------------------------------------------------
	 * Add a table to join with
	 *
	 * @return  void
	 */
	public function addJoin($joinTable = null, $cond = null, $type = '')
	{
		// Check parameters
		if (is_null($joinTable) || is_null($cond) || !in_array($type, array('', 'LEFT', 'RIGHT', 'OUTER', 'INNER', 'LEFT OUTER', 'RIGHT OUTER')))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		
		// Check rights for joined table
		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$joinTable], 's'))
			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$joinTable], FHC_MODEL_ERROR);

		$this->db->join($joinTable, $cond, $type);
		
		return $this->_success(TRUE);
	}
	
	/** ---------------------------------------------------------------
	 * Add order clause
	 *
	 * @return  void
	 */
	public function addOrder($field = null, $type = 'ASC')
	{
		// Check Class-Attributes and parameters
		if (is_null($field) || !in_array($type, array('ASC', 'DESC')))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		
		$this->db->order_by($field, $type);
		
		return $this->_success(TRUE);
	}
	
	/** ---------------------------------------------------------------
	 * Add distinct clause
	 *
	 * @return  void
	 */
	public function addDistinct()
	{
		$this->db->distinct();
	}
	
	/** ---------------------------------------------------------------
	 * Add limit clause
	 *
	 * @return  void
	 */
	public function addLimit($start = null, $end = null)
	{
		// Check Class-Attributes and parameters
		if (!is_numeric($start) || (is_numeric($start) && $start <= 0))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		
		if (is_numeric($end) && $end > $start)
		{
			$this->db->limit($start, $end);
		}
		else
		{
			$this->db->limit($start);
		}
		
		return $this->_success(TRUE);
	}

	/** ---------------------------------------------------------------
	 * Delete data from DB-Table
	 *
	 * @param   string $id  Primary Key for DELETE
	 * @return  array
	 */
	public function delete($id)
	{
		// Check Class-Attributes
		if (is_null($this->dbTable))
			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
		if (is_null($this->pk))
			return $this->_error(lang('fhc_'.FHC_NOPK), FHC_MODEL_ERROR);
		
		// Check rights
		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 'd'))
			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);

		// DB-DELETE
		// Check for composite Primary Key
		if (is_array($id))
		{
			if (isset($id[0]))
				$result = $this->db->delete($this->dbTable, $this->_arrayMergeIndex($this->pk, $id));
			else
				$result = $this->db->delete($this->dbTable, $id);
		}
		else
			$result = $this->db->delete($this->dbTable, array($this->pk => $id));
		if ($result)
			return $this->_success($id);
		else
			return $this->_error($this->db->error(), FHC_DB_ERROR);
	}
	
	/** ---------------------------------------------------------------
	 * Reset the query builder state
	 *
	 * @return  void
	 */
	public function resetQuery()
	{
		$this->db->reset_query();
	}

	/** ---------------------------------------------------------------
	 * Convert PG-Boolean to PHP-Boolean
	 *
	 * @param   char	$b	PG-Char to convert
	 * @return  bool
	 */
	public function pgBoolPhp($b)
	{
		if (is_null($b))
			return null;
		elseif ($b==='t')
			return true;
		else
			return false;
	}

	/** ---------------------------------------------------------------
	 * Convert PG-Array to PHP-Array
	 *
	 * @param   string	$s		PG-String to convert
	 * @param   string	$start	start-point for recursive iterations
	 * @param   string	$end	end-point for recursive iterations
	 * @return  array
	 */
	public function pgArrayPhp($s,$start=0,&$end=NULL)
	{
		if (empty($s) || $s[0]!='{') return NULL;
		$return = array();
		$br = 0;
		$string = false;
		$quote='';
		$len = strlen($s);
		$v = '';
		for ($i=$start+1; $i<$len;$i++)
		{
		    $ch = $s[$i];
		    if (!$string && $ch=='}')
			{
		        if ($v!=='' || !empty($return))
					$return[] = $v;
		        $end = $i;
		        break;
		    }
			else
				if (!$string && $ch=='{')
				    $v = $this->pgArrayPhp($s,$i,$i);
				else
					if (!$string && $ch==',')
					{
				    	$return[] = $v;
				    	$v = '';
					}
					else
						if (!$string && ($ch=='"' || $ch=="'"))
						{
							$string = TRUE;
							$quote = $ch;
						}
						else
							if ($string && $ch==$quote && $s[$i-1]=="\\")
								$v = substr($v,0,-1).$ch;
							else
								if ($string && $ch==$quote && $s[$i-1]!="\\")
									$string = FALSE;
								else
									$v .= $ch;
		}
		return $return;
	}

	/** ---------------------------------------------------------------
	 * Invalid ID
	 *
	 * @param   array $i	Array with indexes.
	 * @param   array $v	Array with values.
	 * @return  array
	 */
	protected function _arrayMergeIndex($i,$v)
	{
		if (count($i) != count($v))
			return false;
		for ($j=0; $j < count($i); $j++)
			$a[$i[$j]] = $v[$j];
		return $a;
	}
	
	/** ---------------------------------------------------------------
	 * Invalid ID
	 *
	 * @param   integer  config.php error code numbers
	 * @return  array
	 */
	protected function _invalid_id($error = '')
	{
		return array(
			'err' => 1,
			'code' => $error,
			'msg' => lang('fhc_' . $error)
		);
	}
}