Packer::pack() - Code Metrics - Inspection of "Merge branch '3.x'" - dvdoug/BoxPacker - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Push — master ( 0bad10...5719ef )

by Doug

created 2021-03-11 21:29 UTC

Packer::pack() A

↳ Parent: Packer

Complexity

Conditions	3
Paths	2

Size

Total Lines	15
Code Lines	8

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	9
CRAP Score	3

Importance

Changes	1
Bugs	0	Features	0

Metric	Value
cc	3
eloc	8
c	1
b	0
f	0
nc	2
nop	0
dl	0
loc	15
ccs	9
cts	9
cp	1
crap	3
rs	10

<?php
/**
 * Box packing (3D bin packing, knapsack problem).
 *
 * @author Doug Wright
 */
declare(strict_types=1);

namespace DVDoug\BoxPacker;

use function count;
use DVDoug\BoxPacker\Exception\ItemTooLargeException;
use DVDoug\BoxPacker\Exception\NoBoxesAvailableException;
use const PHP_INT_MAX;
use Psr\Log\LoggerAwareInterface;
use Psr\Log\LoggerAwareTrait;
use Psr\Log\LogLevel;
use Psr\Log\NullLogger;
use function usort;

/**
 * Actual packer.
 *
 * @author Doug Wright
 */
class Packer implements LoggerAwareInterface
{
    use LoggerAwareTrait;

    /**
     * Number of boxes at which balancing weight is deemed not worth it.
     *
     * @var int
     */
    protected $maxBoxesToBalanceWeight = 12;

    /**
     * List of items to be packed.
     *
     * @var ItemList
     */
    protected $items;

    /**
     * List of box sizes available to pack items into.
     *
     * @var BoxList
     */
    protected $boxes;

    /**
     * Quantities available of each box type.
     *
     * @var array<int, int>
     */
    protected $boxesQtyAvailable = [];

    /**
     * Constructor.
     */
    public function __construct()
    {
        $this->items = new ItemList();
        $this->boxes = new BoxList();

        $this->logger = new NullLogger();
    }

    /**
     * Add item to be packed.
     */
    public function addItem(Item $item, int $qty = 1): void
    {
        for ($i = 0; $i < $qty; ++$i) {
            $this->items->insert($item);
        }
        $this->logger->log(LogLevel::INFO, "added {$qty} x {$item->getDescription()}", ['item' => $item]);
    }

    /**
     * Set a list of items all at once.
     * @param iterable<Item>|ItemList $items
     */
    public function setItems(iterable $items): void
    {
        if ($items instanceof ItemList) {
            $this->items = clone $items;
        } else {
            $this->items = new ItemList();
            foreach ($items as $item) {
                $this->items->insert($item);
            }
        }
    }

    /**
     * Add box size.
     */
    public function addBox(Box $box): void
    {
        $this->boxes->insert($box);
        $this->setBoxQuantity($box, $box instanceof LimitedSupplyBox ? $box->getQuantityAvailable() : PHP_INT_MAX);
        $this->logger->log(LogLevel::INFO, "added box {$box->getReference()}", ['box' => $box]);
    }

    /**
     * Add a pre-prepared set of boxes all at once.
     */
    public function setBoxes(BoxList $boxList): void
    {
        $this->boxes = $boxList;
        foreach ($this->boxes as $box) {
            $this->setBoxQuantity($box, $box instanceof LimitedSupplyBox ? $box->getQuantityAvailable() : PHP_INT_MAX);
        }
    }

    /**
     * Set the quantity of this box type available.
     */
    public function setBoxQuantity(Box $box, int $qty): void
    {
        $this->boxesQtyAvailable[spl_object_id($box)] = $qty;
    }

    /**
     * Number of boxes at which balancing weight is deemed not worth the extra computation time.
     */
    public function getMaxBoxesToBalanceWeight(): int
    {
        return $this->maxBoxesToBalanceWeight;
    }

    /**
     * Number of boxes at which balancing weight is deemed not worth the extra computation time.
     */
    public function setMaxBoxesToBalanceWeight(int $maxBoxesToBalanceWeight): void
    {
        $this->maxBoxesToBalanceWeight = $maxBoxesToBalanceWeight;
    }

    /**
     * Pack items into boxes.
     */
    public function pack(): PackedBoxList
    {
        $this->sanityPrecheck();
        $packedBoxes = $this->doVolumePacking();

        //If we have multiple boxes, try and optimise/even-out weight distribution
        if ($packedBoxes->count() > 1 && $packedBoxes->count() <= $this->maxBoxesToBalanceWeight) {
            $redistributor = new WeightRedistributor($this->boxes, $this->boxesQtyAvailable);
            $redistributor->setLogger($this->logger);
            $packedBoxes = $redistributor->redistributeWeight($packedBoxes);
        }

        $this->logger->log(LogLevel::INFO, "[PACKING COMPLETED], {$packedBoxes->count()} boxes");

        return $packedBoxes;
    }

    /**
     * Pack items into boxes using the principle of largest volume item first.
     *
     * @throws NoBoxesAvailableException
     */
    public function doVolumePacking(bool $singlePassMode = false, bool $enforceSingleBox = false): PackedBoxList
    {
        $packedBoxes = new PackedBoxList();

        //Keep going until everything packed
        while ($this->items->count()) {
            $packedBoxesIteration = [];

            //Loop through boxes starting with smallest, see what happens
            foreach ($this->getBoxList($enforceSingleBox) as $box) {
                $volumePacker = new VolumePacker($box, $this->items);
                $volumePacker->setLogger($this->logger);
                $volumePacker->setSinglePassMode($singlePassMode);
                $packedBox = $volumePacker->pack();
                if ($packedBox->getItems()->count()) {
                    $packedBoxesIteration[] = $packedBox;

                    //Have we found a single box that contains everything?
                    if ($packedBox->getItems()->count() === $this->items->count()) {
                        break;
                    }
                }
            }

            try {
                //Find best box of iteration, and remove packed items from unpacked list
                $bestBox = $this->findBestBoxFromIteration($packedBoxesIteration);
            } catch (NoBoxesAvailableException $e) {
                if ($enforceSingleBox) {
                    return new PackedBoxList();
                }
                throw $e;
            }

            $this->items->removePackedItems($bestBox->getItems());

            $packedBoxes->insert($bestBox);
            --$this->boxesQtyAvailable[spl_object_id($bestBox->getBox())];
        }

        return $packedBoxes;
    }

    /**
     * Get a "smart" ordering of the boxes to try packing items into. The initial BoxList is already sorted in order
     * so that the smallest boxes are evaluated first, but this means that time is spent on boxes that cannot possibly
     * hold the entire set of items due to volume limitations. These should be evaluated first.
     *
     * @return iterable<Box>
     */
    protected function getBoxList(bool $enforceSingleBox = false): iterable
    {
        $itemVolume = 0;
        foreach ($this->items as $item) {
            $itemVolume += $item->getWidth() * $item->getLength() * $item->getDepth();
        }

        $preferredBoxes = [];
        $otherBoxes = [];
        foreach ($this->boxes as $box) {
            if ($this->boxesQtyAvailable[spl_object_id($box)] > 0) {
                if ($box->getInnerWidth() * $box->getInnerLength() * $box->getInnerDepth() >= $itemVolume) {
                    $preferredBoxes[] = $box;
                } elseif (!$enforceSingleBox) {
                    $otherBoxes[] = $box;
                }
            }
        }

        return array_merge($preferredBoxes, $otherBoxes);
    }

    /**
     * @param PackedBox[] $packedBoxes
     */
    protected function findBestBoxFromIteration(array $packedBoxes): PackedBox
    {
        if (count($packedBoxes) === 0) {
            throw new NoBoxesAvailableException("No boxes could be found for item '{$this->items->top()->getDescription()}'", $this->items->top());
        }

        usort($packedBoxes, [$this, 'compare']);

        return $packedBoxes[0];
    }

    private function sanityPrecheck(): void
    {
        /** @var Item $item */
        foreach ($this->items as $item) {
            $possibleFits = 0;

            /** @var Box $box */
            foreach ($this->boxes as $box) {
                if ($item->getWeight() <= ($box->getMaxWeight() - $box->getEmptyWeight())) {
                    $possibleFits += count((new OrientatedItemFactory($box))->getPossibleOrientationsInEmptyBox($item));
                }
            }

            if ($possibleFits === 0) {
                throw new ItemTooLargeException("Item '{$item->getDescription()}' is too large to fit into any box", $item);
            }
        }
    }

    private static function compare(PackedBox $boxA, PackedBox $boxB): int
    {
        $choice = $boxB->getItems()->count() <=> $boxA->getItems()->count();

        if ($choice === 0) {
            $choice = $boxB->getVolumeUtilisation() <=> $boxA->getVolumeUtilisation();
        }
        if ($choice === 0) {
            $choice = $boxB->getUsedVolume() <=> $boxA->getUsedVolume();
        }

        return $choice;
    }
}


1		<?php
2		/**
3		* Box packing (3D bin packing, knapsack problem).
4		*
5		* @author Doug Wright
6		*/
7		declare(strict_types=1);
8
9		namespace DVDoug\BoxPacker;
10
11		use function count;
12		use DVDoug\BoxPacker\Exception\ItemTooLargeException;
13		use DVDoug\BoxPacker\Exception\NoBoxesAvailableException;
14		use const PHP_INT_MAX;
15		use Psr\Log\LoggerAwareInterface;
16		use Psr\Log\LoggerAwareTrait;
17		use Psr\Log\LogLevel;
18		use Psr\Log\NullLogger;
19		use function usort;
20
21		/**
22		* Actual packer.
23		*
24		* @author Doug Wright
25		*/
26		class Packer implements LoggerAwareInterface
27		{
28		use LoggerAwareTrait;
29
30		/**
31		* Number of boxes at which balancing weight is deemed not worth it.
32		*
33		* @var int
34		*/
35		protected $maxBoxesToBalanceWeight = 12;
36
37		/**
38		* List of items to be packed.
39		*
40		* @var ItemList
41		*/
42		protected $items;
43
44		/**
45		* List of box sizes available to pack items into.
46		*
47		* @var BoxList
48		*/
49		protected $boxes;
50
51		/**
52		* Quantities available of each box type.
53		*
54		* @var array<int, int>
55		*/
56		protected $boxesQtyAvailable = [];
57
58		/**
59		* Constructor.
60		*/
61	42	public function __construct()
62		{
63	42	$this->items = new ItemList();
64	42	$this->boxes = new BoxList();
65
66	42	$this->logger = new NullLogger();
67	42	}
68
69		/**
70		* Add item to be packed.
71		*/
72	40	public function addItem(Item $item, int $qty = 1): void
73		{
74	40	for ($i = 0; $i < $qty; ++$i) {
75	40	$this->items->insert($item);
76		}
77	40	$this->logger->log(LogLevel::INFO, "added {$qty} x {$item->getDescription()}", ['item' => $item]);
78	40	}
79
80		/**
81		* Set a list of items all at once.
82		* @param iterable<Item>\|ItemList $items
83		*/
84	6	public function setItems(iterable $items): void
85		{
86	6	if ($items instanceof ItemList) {
87		$this->items = clone $items;
88		} else {
89	6	$this->items = new ItemList();
90	6	foreach ($items as $item) {
91	6	$this->items->insert($item);
92		}
93		}
94	6	}
95
96		/**
97		* Add box size.
98		*/
99	38	public function addBox(Box $box): void
100		{
101	38	$this->boxes->insert($box);
102	38	$this->setBoxQuantity($box, $box instanceof LimitedSupplyBox ? $box->getQuantityAvailable() : PHP_INT_MAX);
103	38	$this->logger->log(LogLevel::INFO, "added box {$box->getReference()}", ['box' => $box]);
104	38	}
105
106		/**
107		* Add a pre-prepared set of boxes all at once.
108		*/
109	6	public function setBoxes(BoxList $boxList): void
110		{
111	6	$this->boxes = $boxList;
112	6	foreach ($this->boxes as $box) {
113	6	$this->setBoxQuantity($box, $box instanceof LimitedSupplyBox ? $box->getQuantityAvailable() : PHP_INT_MAX);
114		}
115	6	}
116
117		/**
118		* Set the quantity of this box type available.
119		*/
120	38	public function setBoxQuantity(Box $box, int $qty): void
121		{
122	38	$this->boxesQtyAvailable[spl_object_id($box)] = $qty;
123	38	}
124
125		/**
126		* Number of boxes at which balancing weight is deemed not worth the extra computation time.
127		*/
128	2	public function getMaxBoxesToBalanceWeight(): int
129		{
130	2	return $this->maxBoxesToBalanceWeight;
131		}
132
133		/**
134		* Number of boxes at which balancing weight is deemed not worth the extra computation time.
135		*/
136	4	public function setMaxBoxesToBalanceWeight(int $maxBoxesToBalanceWeight): void
137		{
138	4	$this->maxBoxesToBalanceWeight = $maxBoxesToBalanceWeight;
139	4	}
140
141		/**
142		* Pack items into boxes.
143		*/
144	40	public function pack(): PackedBoxList
145		{
146	40	$this->sanityPrecheck();
147	36	$packedBoxes = $this->doVolumePacking();
148
149		//If we have multiple boxes, try and optimise/even-out weight distribution
150	34	if ($packedBoxes->count() > 1 && $packedBoxes->count() <= $this->maxBoxesToBalanceWeight) {
151	14	$redistributor = new WeightRedistributor($this->boxes, $this->boxesQtyAvailable);
152	14	$redistributor->setLogger($this->logger);
153	14	$packedBoxes = $redistributor->redistributeWeight($packedBoxes);
154		}
155
156	34	$this->logger->log(LogLevel::INFO, "[PACKING COMPLETED], {$packedBoxes->count()} boxes");
157
158	34	return $packedBoxes;
159		}
160
161		/**
162		* Pack items into boxes using the principle of largest volume item first.
163		*
164		* @throws NoBoxesAvailableException
165		*/
166	36	public function doVolumePacking(bool $singlePassMode = false, bool $enforceSingleBox = false): PackedBoxList
167		{
168	36	$packedBoxes = new PackedBoxList();
169
170		//Keep going until everything packed
171	36	while ($this->items->count()) {
172	36	$packedBoxesIteration = [];
173
174		//Loop through boxes starting with smallest, see what happens
175	36	foreach ($this->getBoxList($enforceSingleBox) as $box) {
176	36	$volumePacker = new VolumePacker($box, $this->items);
177	36	$volumePacker->setLogger($this->logger);
178	36	$volumePacker->setSinglePassMode($singlePassMode);
179	36	$packedBox = $volumePacker->pack();
180	36	if ($packedBox->getItems()->count()) {
181	36	$packedBoxesIteration[] = $packedBox;
182
183		//Have we found a single box that contains everything?
184	36	if ($packedBox->getItems()->count() === $this->items->count()) {
185	34	break;
186		}
187		}
188		}
189
190		try {
191		//Find best box of iteration, and remove packed items from unpacked list
192	36	$bestBox = $this->findBestBoxFromIteration($packedBoxesIteration);
193	4	} catch (NoBoxesAvailableException $e) {
194	4	if ($enforceSingleBox) {
195	2	return new PackedBoxList();
196		}
197	2	throw $e;
198		}
199
200	36	$this->items->removePackedItems($bestBox->getItems());
201
202	36	$packedBoxes->insert($bestBox);
203	36	--$this->boxesQtyAvailable[spl_object_id($bestBox->getBox())];
204		}
205
206	34	return $packedBoxes;
207		}
208
209		/**
210		* Get a "smart" ordering of the boxes to try packing items into. The initial BoxList is already sorted in order
211		* so that the smallest boxes are evaluated first, but this means that time is spent on boxes that cannot possibly
212		* hold the entire set of items due to volume limitations. These should be evaluated first.
213		*
214		* @return iterable<Box>
215		*/
216	36	protected function getBoxList(bool $enforceSingleBox = false): iterable
217		{
218	36	$itemVolume = 0;
219	36	foreach ($this->items as $item) {
220	36	$itemVolume += $item->getWidth() * $item->getLength() * $item->getDepth();
221		}
222
223	36	$preferredBoxes = [];
224	36	$otherBoxes = [];
225	36	foreach ($this->boxes as $box) {
226	36	if ($this->boxesQtyAvailable[spl_object_id($box)] > 0) {
227	36	if ($box->getInnerWidth() * $box->getInnerLength() * $box->getInnerDepth() >= $itemVolume) {
228	34	$preferredBoxes[] = $box;
229	12	} elseif (!$enforceSingleBox) {
230	12	$otherBoxes[] = $box;
231		}
232		}
233		}
234
235	36	return array_merge($preferredBoxes, $otherBoxes);
236		}
237
238		/**
239		* @param PackedBox[] $packedBoxes
240		*/
241	36	protected function findBestBoxFromIteration(array $packedBoxes): PackedBox
242		{
243	36	if (count($packedBoxes) === 0) {
244	4	throw new NoBoxesAvailableException("No boxes could be found for item '{$this->items->top()->getDescription()}'", $this->items->top());
245		}
246
247	36	usort($packedBoxes, [$this, 'compare']);
248
249	36	return $packedBoxes[0];
250		}
251
252	40	private function sanityPrecheck(): void
253		{
254		/** @var Item $item */
255	40	foreach ($this->items as $item) {
256	40	$possibleFits = 0;
257
258		/** @var Box $box */
259	40	foreach ($this->boxes as $box) {
260	38	if ($item->getWeight() <= ($box->getMaxWeight() - $box->getEmptyWeight())) {
261	38	$possibleFits += count((new OrientatedItemFactory($box))->getPossibleOrientationsInEmptyBox($item));
262		}
263		}
264
265	40	if ($possibleFits === 0) {
266	6	throw new ItemTooLargeException("Item '{$item->getDescription()}' is too large to fit into any box", $item);
267		}
268		}
269	36	}
270
271	6	private static function compare(PackedBox $boxA, PackedBox $boxB): int
272		{
273	6	$choice = $boxB->getItems()->count() <=> $boxA->getItems()->count();
274
275	6	if ($choice === 0) {
276	6	$choice = $boxB->getVolumeUtilisation() <=> $boxA->getVolumeUtilisation();
277		}
278	6	if ($choice === 0) {
279	6	$choice = $boxB->getUsedVolume() <=> $boxA->getUsedVolume();
280		}
281
282	6	return $choice;
283		}
284		}
285

dvdoug / BoxPacker

Push — master ( 0bad10...5719ef )

Packer::pack() A

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