<?php
class Sale extends CI_Model
{
	public function get_info($sale_id)
	{
		$this->db->from('sales');
		$this->db->join('people', 'people.person_id = sales.customer_id', 'LEFT');
		$this->db->where('sale_id',$sale_id);
		return $this->db->get();
	}
	
	function get_invoice_count()
	{
		$this->db->from('sales');
		$this->db->where('invoice_number is not null');
		return $this->db->count_all_results();
	}
	
	function get_sale_by_invoice_number($invoice_number)
	{
		$this->db->from('sales');
		$this->db->where('invoice_number', $invoice_number);
		return $this->db->get();
	}
	
	function get_invoice_number_for_year($year, $start_from = 0) 
	{
		$this->db->select("COUNT( 1 ) AS invoice_number_year", FALSE);
		$this->db->from('sales');
		$this->db->where("DATE_FORMAT(sale_time, '%Y' ) = ", $year, FALSE);
		$this->db->where("invoice_number IS NOT ", "NULL", FALSE);
		$result = $this->db->get()->row_array();
		return ($start_from + $result[ 'invoice_number_year' ] + 1);
	}

	function exists($sale_id)
	{
		$this->db->from('sales');
		$this->db->where('sale_id',$sale_id);
		$query = $this->db->get();

		return ($query->num_rows()==1);
	}
	
	function update($sale_data, $sale_id)
	{
		$this->db->where('sale_id', $sale_id);
		$success = $this->db->update('sales',$sale_data);
		
		return $success;
	}
	
	function save ($items,$customer_id,$employee_id,$comment,$invoice_number,$payments,$sale_id=false)
	{
		if(count($items)==0)
			return -1;

		//Alain Multiple payments
		//Build payment types string
		$payment_types='';
		foreach($payments as $payment_id=>$payment)
		{
			$payment_types=$payment_types.$payment['payment_type'].': '.to_currency($payment['payment_amount']).'<br />';
		}

		$sales_data = array(
			'sale_time' => date('Y-m-d H:i:s'),
			'customer_id'=> $this->Customer->exists($customer_id) ? $customer_id : null,
			'employee_id'=>$employee_id,
			'payment_type'=>$payment_types,
			'comment'=>$comment,
			'invoice_number'=>$invoice_number
		);

		//Run these queries as a transaction, we want to make sure we do all or nothing
		$this->db->trans_start();

		$this->db->insert('sales',$sales_data);
		$sale_id = $this->db->insert_id();

		foreach($payments as $payment_id=>$payment)
		{
			if ( substr( $payment['payment_type'], 0, strlen( $this->lang->line('sales_giftcard') ) ) == $this->lang->line('sales_giftcard') )
			{
				/* We have a gift card and we have to deduct the used value from the total value of the card. */
				$splitpayment = explode( ':', $payment['payment_type'] );
				$cur_giftcard_value = $this->Giftcard->get_giftcard_value( $splitpayment[1] );
				$this->Giftcard->update_giftcard_value( $splitpayment[1], $cur_giftcard_value - $payment['payment_amount'] );
			}

			$sales_payments_data = array
			(
				'sale_id'=>$sale_id,
				'payment_type'=>$payment['payment_type'],
				'payment_amount'=>$payment['payment_amount']
			);
			$this->db->insert('sales_payments',$sales_payments_data);
		}

		foreach($items as $line=>$item)
		{
			$cur_item_info = $this->Item->get_info($item['item_id']);

			$sales_items_data = array
			(
				'sale_id'=>$sale_id,
				'item_id'=>$item['item_id'],
				'line'=>$item['line'],
				'description'=>$item['description'],
				'serialnumber'=>$item['serialnumber'],
				'quantity_purchased'=>$item['quantity'],
				'discount_percent'=>$item['discount'],
				'item_cost_price' => $cur_item_info->cost_price,
				'item_unit_price'=>$item['price'],
				'item_location'=>$item['item_location']
			);

			$this->db->insert('sales_items',$sales_items_data);

			//Update stock quantity
			$item_quantity = $this->Item_quantities->get_item_quantity($item['item_id'], $item['item_location']);       
            $this->Item_quantities->save(array('quantity'=>$item_quantity->quantity - $item['quantity'],
                                              'item_id'=>$item['item_id'],
                                              'location_id'=>$item['item_location']), $item['item_id'], $item['item_location']);
	
			
			//Ramel Inventory Tracking
			//Inventory Count Details
			$qty_buy = -$item['quantity'];
			$sale_remarks ='POS '.$sale_id;
			$inv_data = array
			(
				'trans_date'=>date('Y-m-d H:i:s'),
				'trans_items'=>$item['item_id'],
				'trans_user'=>$employee_id,
				'trans_location'=>$item['item_location'],
				'trans_comment'=>$sale_remarks,
				'trans_inventory'=>$qty_buy
			);
			$this->Inventory->insert($inv_data);
			//------------------------------------Ramel

			$customer = $this->Customer->get_info($customer_id);
 			if ($customer_id == -1 or $customer->taxable)
 			{
				foreach($this->Item_taxes->get_info($item['item_id']) as $row)
				{
					$this->db->insert('sales_items_taxes', array(
						'sale_id' 	=>$sale_id,
						'item_id' 	=>$item['item_id'],
						'line'      =>$item['line'],
						'name'		=>$row['name'],
						'percent' 	=>$row['percent']
					));
				}
			}
		}
		$this->db->trans_complete();
		
		if ($this->db->trans_status() === FALSE)
		{
			return -1;
		}
		
		return $sale_id;
	}
	
	function delete_list($sale_ids, $employee_id,$update_inventory=TRUE) 
	{
		$result = TRUE;
		foreach($sale_ids as $sale_id) {
			$result &= $this->delete($sale_id, $employee_id, $update_inventory);
		}
		return $result;
	}
	
	function delete($sale_id,$employee_id,$update_inventory=TRUE) 
	{
		// start a transaction to assure data integrity
		$this->db->trans_start();
		// first delete all payments
		$this->db->delete('sales_payments', array('sale_id' => $sale_id));
		// then delete all taxes on items
		$this->db->delete('sales_items_taxes', array('sale_id' => $sale_id));
		if ($update_inventory) {
			// defect, not all item deletions will be undone??
			// get array with all the items involved in the sale to update the inventory tracking
			$items = $this->get_sale_items($sale_id)->result_array();
			foreach($items as $item) {
				// create query to update inventory tracking
				$inv_data = array
				(
						'trans_date'=>date('Y-m-d H:i:s'),
						'trans_items'=>$item['item_id'],
						'trans_user'=>$employee_id,
						'trans_comment'=>'Deleting sale ' . $sale_id,
						'trans_location'=>$item['item_location'],
						'trans_inventory'=>$item['quantity_purchased']
	
				);
				// update inventory
				$this->Inventory->insert($inv_data);

				// update quantities
				$this->Item_quantities->change_quantity($item['item_id'],
														$item['item_location'],
														$item['quantity_purchased']);
			}
		}
		// delete all items
		$this->db->delete('sales_items', array('sale_id' => $sale_id));
		// delete sale itself
		$this->db->delete('sales', array('sale_id' => $sale_id));
		// execute transaction
		$this->db->trans_complete();
	
		return $this->db->trans_status();
	}

	function get_sale_items($sale_id)
	{
		$this->db->from('sales_items');
		$this->db->where('sale_id',$sale_id);
		return $this->db->get();
	}

	function get_sale_payments($sale_id)
	{
		$this->db->from('sales_payments');
		$this->db->where('sale_id',$sale_id);
		return $this->db->get();
	}

	function get_customer($sale_id)
	{
		$this->db->from('sales');
		$this->db->where('sale_id',$sale_id);
		return $this->Customer->get_info($this->db->get()->row()->customer_id);
	}
	
	function invoice_number_exists($invoice_number,$sale_id='')
	{
		$this->db->from('sales');
		$this->db->where('invoice_number', $invoice_number);
		if (!empty($sale_id))
		{
			$this->db->where('sale_id !=', $sale_id);
		}
		$query=$this->db->get();
		return ($query->num_rows()==1);
	}

	//We create a temp table that allows us to do easy report/sales queries
	public function create_sales_items_temp_table()
	{
		$this->db->query("DROP TABLE IF EXISTS phppos_sales_items_temp");
		$this->db->query("CREATE TEMPORARY TABLE ".$this->db->dbprefix('sales_items_temp')."
		(SELECT date(sale_time) as sale_date, sale_time, ".$this->db->dbprefix('sales_items').".sale_id, comment,payments.payment_type, customer_id, employee_id, 
		".$this->db->dbprefix('items').".item_id, supplier_id, quantity_purchased, item_cost_price, item_unit_price, SUM(percent) as item_tax_percent,
		discount_percent, (item_unit_price*quantity_purchased-item_unit_price*quantity_purchased*discount_percent/100) as subtotal,
		".$this->db->dbprefix('sales_items').".line as line, serialnumber, ".$this->db->dbprefix('sales_items').".description as description,
		(item_unit_price*quantity_purchased-item_unit_price*quantity_purchased*discount_percent/100)*(1+(SUM(percent)/100)) as total,
		(item_unit_price*quantity_purchased-item_unit_price*quantity_purchased*discount_percent/100)*(SUM(percent)/100) as tax,
		(item_unit_price*quantity_purchased-item_unit_price*quantity_purchased*discount_percent/100) - (item_cost_price*quantity_purchased) as profit
		FROM ".$this->db->dbprefix('sales_items')."
		INNER JOIN ".$this->db->dbprefix('sales')." ON  ".$this->db->dbprefix('sales_items').'.sale_id='.$this->db->dbprefix('sales').'.sale_id'."
		INNER JOIN ".$this->db->dbprefix('items')." ON  ".$this->db->dbprefix('sales_items').'.item_id='.$this->db->dbprefix('items').'.item_id'."
		INNER JOIN (SELECT sale_id, SUM(payment_amount) AS sale_payment_amount, 
		GROUP_CONCAT(payment_type SEPARATOR ', ') AS payment_type FROM " .$this->db->dbprefix('sales_payments') . " GROUP BY sale_id) AS payments 
		ON " . $this->db->dbprefix('sales_items') . '.sale_id'. "=" . "payments.sale_id		
		LEFT OUTER JOIN ".$this->db->dbprefix('suppliers')." ON  ".$this->db->dbprefix('items').'.supplier_id='.$this->db->dbprefix('suppliers').'.person_id'."
		LEFT OUTER JOIN ".$this->db->dbprefix('sales_items_taxes')." ON  "
		.$this->db->dbprefix('sales_items').'.sale_id='.$this->db->dbprefix('sales_items_taxes').'.sale_id'." and "
		.$this->db->dbprefix('sales_items').'.item_id='.$this->db->dbprefix('sales_items_taxes').'.item_id'." and "
		.$this->db->dbprefix('sales_items').'.line='.$this->db->dbprefix('sales_items_taxes').'.line'."
		GROUP BY sale_id, item_id, line)");

		//Update null item_tax_percents to be 0 instead of null
		$this->db->where('item_tax_percent IS NULL');
		$this->db->update('sales_items_temp', array('item_tax_percent' => 0));

		//Update null tax to be 0 instead of null
		$this->db->where('tax IS NULL');
		$this->db->update('sales_items_temp', array('tax' => 0));

		//Update null subtotals to be equal to the total as these don't have tax
		$this->db->query('UPDATE '.$this->db->dbprefix('sales_items_temp'). ' SET total=subtotal WHERE total IS NULL');
	}
	
	public function get_giftcard_value( $giftcardNumber )
	{
		if ( !$this->Giftcard->exists( $this->Giftcard->get_giftcard_id($giftcardNumber)))
			return 0;
		
		$this->db->from('giftcards');
		$this->db->where('giftcard_number',$giftcardNumber);
		return $this->db->get()->row()->value;
	}
}
?>