<?php

namespace app\Libraries;

use App\Models\Attribute;
use App\Models\Item;
use App\Models\Item_kit_items;
use App\Models\Item_quantity;
use App\Models\Receiving;
use App\Models\Stock_location;

use CodeIgniter\Session\Session;
use Config\OSPOS;

/**
 * Receiving library
 *
 * Library with utilities to manage receivings
 */
class Receiving_lib
{
	private Attribute $attribute;
	private Item $item;
	private Item_kit_items $item_kit_items;
	private Item_quantity $item_quantity;
	private Receiving $receiving;
	private Stock_location $stock_location;
	private Session $session;

	public function __construct()
	{
		$this->attribute = model(Attribute::class);
		$this->item = model(Item::class);
		$this->item_kit_items = model(Item_kit_items::class);
		$this->item_quantity = model(Item_quantity::class);
		$this->receiving = model(Receiving::class);
		$this->stock_location = model(Stock_location::class);

		$this->session = session();
	}

	/**
	 * @return array
	 */
	public function get_cart(): array
	{
		if(!$this->session->get('recv_cart'))
		{
			$this->set_cart ([]);
		}

		return $this->session->get('recv_cart');
	}

	/**
	 * @param array $cart_data
	 * @return void
	 */
	public function set_cart(array $cart_data): void
	{
		$this->session->set('recv_cart', $cart_data);
	}

	/**
	 * @return void
	 */
	public function empty_cart(): void
	{
		$this->session->remove('recv_cart');
	}

	/**
	 * @return int
	 */
	public function get_supplier(): int
	{
		if(!$this->session->get('recv_supplier'))
		{
			$this->set_supplier(-1);	//TODO: Replace -1 with a constant.
		}

		return $this->session->get('recv_supplier');
	}

	/**
	 * @param int $supplier_id
	 * @return void
	 */
	public function set_supplier(int $supplier_id): void
	{
		$this->session->set('recv_supplier', $supplier_id);
	}

	/**
	 * @return void
	 */
	public function remove_supplier(): void
	{
		$this->session->remove('recv_supplier');
	}

	/**
	 * @return string
	 */
	public function get_mode(): string
	{
		if(!$this->session->get('recv_mode'))
		{
			$this->set_mode('receive');
		}

		return $this->session->get('recv_mode');
	}

	/**
	 * @param string $mode
	 * @return void
	 */
	public function set_mode(string $mode): void
	{
		$this->session->set('recv_mode', $mode);
	}

	/**
	 * @return void
	 */
	public function clear_mode(): void	//TODO: This function verb is inconsistent from the others.  Consider refactoring to remove_mode()
	{
		$this->session->remove('recv_mode');
	}

	/**
	 * @return int
	 */
	public function get_stock_source(): int
	{
		if(!$this->session->get('recv_stock_source'))
		{
			$this->set_stock_source($this->stock_location->get_default_location_id('receivings'));
		}

		return $this->session->get('recv_stock_source');
	}

	/**
	 * @return string
	 */
	public function get_comment(): string
	{
		$comment = $this->session->get('recv_comment');

		return empty($comment) ? '' : $comment;
	}

	/**
	 * @param string $comment
	 * @return void
	 */
	public function set_comment(string $comment): void
	{
		$this->session->set('recv_comment', $comment);
	}

	/**
	 * @return void
	 */
	public function clear_comment(): void	//TODO: This function verb is inconsistent from the others.  Consider refactoring to remove_comment()
	{
		$this->session->remove('recv_comment');
	}

	/**
	 * @return string
	 */
	public function get_reference(): string
	{
		return $this->session->get('recv_reference') ?? '';
	}

	/**
	 * @param string $reference
	 * @return void
	 */
	public function set_reference(string $reference): void
	{
		$this->session->set('recv_reference', $reference);
	}

	/**
	 * @return void
	 */
	public function clear_reference(): void	//TODO: This function verb is inconsistent from the others.  Consider refactoring to remove_reference()
	{
		$this->session->remove('recv_reference');
	}

	/**
	 * @return bool
	 */
	public function is_print_after_sale(): bool
	{
		return $this->session->get('recv_print_after_sale') == 'true'
			|| $this->session->get('recv_print_after_sale') == '1';
	}

	/**
	 * @param bool $print_after_sale
	 * @return void
	 */
	public function set_print_after_sale(bool $print_after_sale): void
	{
		$this->session->set('recv_print_after_sale', $print_after_sale);
	}

	/**
	 * @param int $stock_source
	 * @return void
	 */
	public function set_stock_source(int $stock_source): void
	{
		$this->session->set('recv_stock_source', $stock_source);
	}

	/**
	 * @return void
	 */
	public function clear_stock_source(): void
	{
		$this->session->remove('recv_stock_source');
	}

	/**
	 * @return string
	 */
	public function get_stock_destination(): string
	{
		if(!$this->session->get('recv_stock_destination'))
		{
			$this->set_stock_destination($this->stock_location->get_default_location_id('receivings'));
		}

		return $this->session->get('recv_stock_destination');
	}

	/**
	 * @param string $stock_destination
	 * @return void
	 */
	public function set_stock_destination(string $stock_destination): void
	{
		$this->session->set('recv_stock_destination', $stock_destination);
	}

	/**
	 * @return void
	 */
	public function clear_stock_destination(): void
	{
		$this->session->remove('recv_stock_destination');
	}
	//TODO: This array signature needs to be reworked.  It's way too long. Perhaps an object needs to be passed rather than these?

	/**
	 * @param int $item_id
	 * @param int $quantity
	 * @param int|null $item_location
	 * @param float $discount
	 * @param int $discount_type
	 * @param float|null $price
	 * @param string|null $description
	 * @param string|null $serialnumber
	 * @param float|null $receiving_quantity
	 * @param int|null $receiving_id
	 * @param bool $include_deleted
	 * @return bool
	 */
	public function add_item(int $item_id, int $quantity = 1, int $item_location = null, float $discount = 0, int $discount_type = 0, float $price = null, string $description = null, string $serialnumber = null, float $receiving_quantity = null, int $receiving_id = null, bool $include_deleted = false): bool
	{
		$config = config(OSPOS::class)->settings;

		//make sure item exists in database.
		if(!$this->item->exists($item_id, $include_deleted))
		{
			//try to get item id given an item_number
			$item_id = $this->item->get_item_id($item_id, $include_deleted);

			if(!$item_id)
			{
				return false;
			}
		}

		//Get items in the receiving so far.
		$items = $this->get_cart();

		//We need to loop through all items in the cart.
		//If the item is already there, get it's key($updatekey).
		//We also need to get the next key that we are going to use in case we need to add the
		//item to the list. Since items can be deleted, we can't use a count. we use the highest key + 1.

		$maxkey = 0;					//Highest key so far
		$itemalreadyinsale = false;		//We did not find the item yet.
		$updatekey = 0;					//Key to use to update(quantity)

		foreach($items as $item)
		{
			//We primed the loop so maxkey is 0 the first time.
			//Also, we have stored the key in the element itself, so we can compare.
			//There is an array public function to get the associated key for an element, but I like it better
			//like that!

			if($maxkey <= $item['line'])
			{
				$maxkey = $item['line'];
			}

			if($item['item_id'] == $item_id && $item['item_location'] == $item_location)
			{
				$itemalreadyinsale = true;
				$updatekey = $item['line'];
			}
		}

		$insertkey = $maxkey + 1;
		$item_info = $this->item->get_info($item_id);

		//array records are identified by $insertkey and item_id is just another field.
		$price = $price != null ? $price : $item_info->cost_price;

		if($config['multi_pack_enabled'])
		{
			$item_info->name .= NAME_SEPARATOR . $item_info->pack_name;
		}

		if ($item_info->receiving_quantity == 0 || $item_info->receiving_quantity == 1)
		{
			$receiving_quantity_choices = [1  => 'x1'];
		}
		else
		{
			$receiving_quantity_choices = [
				to_quantity_decimals($item_info->receiving_quantity) => 'x' . to_quantity_decimals($item_info->receiving_quantity),
				1  => 'x1'
			];
		}

		if(is_null($receiving_quantity))
		{
			$receiving_quantity = $item_info->receiving_quantity;
		}

		$attribute_links = $this->attribute->get_link_values($item_id, 'receiving_id', $receiving_id, Attribute::SHOW_IN_RECEIVINGS)->getRowObject();

		$item = [
			$insertkey => [
				'item_id' => $item_id,
				'item_location' => $item_location,
				'item_number' => $item_info->item_number,
				'stock_name' => $this->stock_location->get_location_name($item_location),
				'line' => $insertkey,
				'name' => $item_info->name,
				'description' => $description != null ? $description: $item_info->description,
				'serialnumber' => $serialnumber != null ? $serialnumber: '',
				'attribute_values' => $attribute_links->attribute_values,
				'attribute_dtvalues' => $attribute_links->attribute_dtvalues,
				'allow_alt_description' => $item_info->allow_alt_description,
				'is_serialized' => $item_info->is_serialized,
				'quantity' => $quantity,
				'discount' => $discount,
				'discount_type' => $discount_type,
				'in_stock' => $this->item_quantity->get_item_quantity($item_id, $item_location)->quantity,
				'price' => $price,
				'receiving_quantity' => $receiving_quantity,
				'receiving_quantity_choices' => $receiving_quantity_choices,
				'total' => $this->get_item_total($quantity, $price, $discount, $discount_type, $receiving_quantity)
			]
		];

		//Item already exists
		if($itemalreadyinsale)	//TODO: This variable does not adhere to naming conventions.
		{
			$items[$updatekey]['quantity'] += $quantity;
			$items[$updatekey]['total'] = $this->get_item_total($items[$updatekey]['quantity'], $price, $discount, $discount_type, $items[$updatekey]['receiving_quantity']);
		}
		else
		{
			//add to existing array
			$items += $item;
		}

		$this->set_cart($items);

		return true;
	}

	/**
	 * @param $line
	 * @param string $description
	 * @param string $serialnumber
	 * @param float $quantity
	 * @param float $discount
	 * @param int|null $discount_type
	 * @param float $price
	 * @param float $receiving_quantity
	 * @return bool
	 */
	public function edit_item($line, string $description, string $serialnumber, float $quantity, float $discount, ?int $discount_type, float $price, float $receiving_quantity): bool
	{
		$items = $this->get_cart();
		if(isset($items[$line]))
		{
			$line = &$items[$line];
			$line['description'] = $description;
			$line['serialnumber'] = $serialnumber;
			$line['quantity'] = $quantity;
			$line['receiving_quantity'] = $receiving_quantity;
			$line['discount'] = $discount;

			if(!is_null($discount_type))
			{
				$line['discount_type'] = $discount_type;
			}

			$line['price'] = $price;
			$line['total'] = $this->get_item_total($quantity, $price, $discount, $discount_type, $receiving_quantity);
			$this->set_cart($items);
		}

		return false;	//TODO: This function will always return false.
	}

	/**
	 * @param $line int|string The item_number or item_id of the item to be removed from the receiving.
	 */
	public function delete_item($line): void
	{
		$items = $this->get_cart();
		unset($items[$line]);
		$this->set_cart($items);
	}

	/**
	 * @param int $receipt_receiving_id
	 * @return void
	 */
	public function return_entire_receiving(int $receipt_receiving_id): void
	{
		//RECV #
		$pieces = explode(' ', $receipt_receiving_id);

		if(preg_match("/(RECV|KIT)/", $pieces[0]))	//TODO: this needs to be converted to ternary notation.
		{
			$receiving_id = $pieces[1];
		}
		else
		{
			$receiving_id = $this->receiving->get_receiving_by_reference($receipt_receiving_id)->getRow()->receiving_id;
		}

		$this->empty_cart();
		$this->remove_supplier();
		$this->clear_comment();

		foreach($this->receiving->get_receiving_items($receiving_id)->getResult() as $row)
		{
			$this->add_item($row->item_id, -$row->quantity_purchased, $row->item_location, $row->discount, $row->discount_type, $row->item_unit_price, $row->description, $row->serialnumber, $row->receiving_quantity, $receiving_id, true);
		}

		$this->set_supplier($this->receiving->get_supplier($receiving_id)->person_id);
	}

	/**
	 * @param string $external_item_kit_id
	 * @param int $item_location
	 * @param float $discount
	 * @param int $discount_type
	 * @return void
	 */
	public function add_item_kit(string $external_item_kit_id, int $item_location, float $discount, int $discount_type): void
	{
		//KIT #
		$pieces = explode(' ',$external_item_kit_id);
		$item_kit_id = count($pieces) > 1 ? $pieces[1] : $external_item_kit_id;

		foreach($this->item_kit_items->get_info($item_kit_id) as $item_kit_item)
		{
			$this->add_item($item_kit_item['item_id'], $item_kit_item['quantity'], $item_location, $discount, $discount_type);
		}
	}

	/**
	 * @param int $receiving_id
	 * @return void
	 */
	public function copy_entire_receiving(int $receiving_id): void
	{
		$this->empty_cart();
		$this->remove_supplier();

		foreach($this->receiving->get_receiving_items($receiving_id)->getResult() as $row)
		{
			$this->add_item($row->item_id, $row->quantity_purchased, $row->item_location, $row->discount, $row->discount_type, $row->item_unit_price, $row->description, $row->serialnumber, $row->receiving_quantity, $receiving_id, true);
		}

		$this->set_supplier((int) $this->receiving->get_supplier($receiving_id)->person_id);
		//$this->set_reference($this->receiving->get_info($receiving_id)->getRow()->reference);	//TODO: If this code won't be added back in, then let's delete it.
	}

	/**
	 * @return void
	 */
	public function clear_all(): void
	{
		$this->clear_mode();
		$this->empty_cart();
		$this->remove_supplier();
		$this->clear_comment();
		$this->clear_reference();
	}

	/**
	 * @param float $quantity
	 * @param float $price
	 * @param float $discount
	 * @param int|null $discount_type
	 * @param float $receiving_quantity
	 * @return string
	 */
	public function get_item_total(float $quantity, float $price, float $discount, ?int $discount_type, float $receiving_quantity): string
	{
		$extended_quantity = bcmul($quantity, $receiving_quantity);
		$total = bcmul($extended_quantity, $price);
		$discount_amount = $discount;

		if($discount_type == PERCENT)	//TODO: === ?
		{
			$discount_fraction = bcdiv($discount, 100);
			$discount_amount = bcmul($total, $discount_fraction);
		}

		return bcsub($total, $discount_amount);
	}

	/**
	 * @return string
	 */
	public function get_total(): string
	{
		$total = 0;
		foreach($this->get_cart() as $item)
		{
			$total = bcadd($total, $this->get_item_total(($item['quantity']), $item['price'], $item['discount'], $item['discount_type'], $item['receiving_quantity']));
		}

		return $total;
	}
}