Completed
Push — master ( 13a8ff...b1bff8 )
by Doug
04:21
created

VolumePacker::getOrientationForItem()   B

Complexity

Conditions 1
Paths 1

Duplication

Lines 0
Ratio 0 %

Size

Total Lines 28
Code Lines 20

Code Coverage

Tests 14
CRAP Score 1

Importance

Changes 0
Metric Value
dl 0
loc 28
ccs 14
cts 14
cp 1
rs 8.8571
c 0
b 0
f 0
cc 1
eloc 20
nc 1
nop 6
crap 1
1
<?php
2
/**
3
 * Box packing (3D bin packing, knapsack problem)
4
 * @package BoxPacker
5
 * @author Doug Wright
6
 */
7
namespace DVDoug\BoxPacker;
8
9
use Psr\Log\LoggerAwareInterface;
10
use Psr\Log\LoggerAwareTrait;
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use Psr\Log\NullLogger;
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13
/**
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 * Actual packer
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 * @author Doug Wright
16
 * @package BoxPacker
17
 */
18
class VolumePacker implements LoggerAwareInterface
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{
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    use LoggerAwareTrait;
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22
    /**
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     * Box to pack items into
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     * @var Box
25
     */
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    protected $box;
27
28
    /**
29
     * List of items to be packed
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     * @var ItemList
31
     */
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    protected $items;
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34
    /**
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     * Remaining width of the box to pack items into
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     * @var int
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     */
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    protected $widthLeft;
39
40
    /**
41
     * Remaining length of the box to pack items into
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     * @var int
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     */
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    protected $lengthLeft;
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46
    /**
47
     * Remaining depth of the box to pack items into
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     * @var int
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     */
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    protected $depthLeft;
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    /**
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     * Remaining weight capacity of the box
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     * @var int
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     */
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    protected $remainingWeight;
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58
    /**
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     * Used width inside box for packing items
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     * @var int
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     */
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    protected $usedWidth = 0;
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64
    /**
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     * Used length inside box for packing items
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     * @var int
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     */
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    protected $usedLength = 0;
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    /**
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     * Used depth inside box for packing items
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     * @var int
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     */
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    protected $usedDepth = 0;
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76
    /**
77
     * @var int
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     */
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    protected $layerWidth = 0;
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    /**
82
     * @var int
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     */
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    protected $layerLength = 0;
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86
    /**
87
     * @var int
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     */
89
    protected $layerDepth = 0;
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91
    /**
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     * Constructor
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     *
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     * @param Box      $box
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     * @param ItemList $items
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     */
97 33
    public function __construct(Box $box, ItemList $items)
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    {
99 33
        $this->logger = new NullLogger();
100
101 33
        $this->box = $box;
102 33
        $this->items = $items;
103
104 33
        $this->depthLeft = $this->box->getInnerDepth();
105 33
        $this->remainingWeight = $this->box->getMaxWeight() - $this->box->getEmptyWeight();
106 33
        $this->widthLeft = $this->box->getInnerWidth();
107 33
        $this->lengthLeft = $this->box->getInnerLength();
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    }
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    /**
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     * Pack as many items as possible into specific given box
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     * @return PackedBox packed box
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     */
114 33
    public function pack()
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    {
116 33
        $this->logger->debug("[EVALUATING BOX] {$this->box->getReference()}");
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118 33
        $packedItems = new ItemList;
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120 33
        $this->layerWidth = $this->layerLength = $this->layerDepth = 0;
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122 33
        $prevItem = null;
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124 33
        while (!$this->items->isEmpty()) {
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126 33
            $itemToPack = $this->items->extract();
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            //skip items that are simply too heavy
129 33
            if (!$this->checkNonDimensionalConstraints($itemToPack, $packedItems)) {
130 5
                continue;
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            }
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133 33
            $nextItem = !$this->items->isEmpty() ? $this->items->top() : null;
134 33
            $orientatedItem = $this->getOrientationForItem($itemToPack, $prevItem, $nextItem, $this->widthLeft, $this->lengthLeft, $this->depthLeft);
135
136 33
            if ($orientatedItem) {
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138 33
                $packedItems->insert($orientatedItem->getItem());
139 33
                $this->remainingWeight -= $orientatedItem->getItem()->getWeight();
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                $this->lengthLeft -= $orientatedItem->getLength();
142 33
                $this->layerLength += $orientatedItem->getLength();
143 33
                $this->layerWidth = max($orientatedItem->getWidth(), $this->layerWidth);
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145 33
                $this->layerDepth = max($this->layerDepth, $orientatedItem->getDepth()); //greater than 0, items will always be less deep
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147 33
                $this->usedLength = max($this->usedLength, $this->layerLength);
148 33
                $this->usedWidth = max($this->usedWidth, $this->layerWidth);
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                //allow items to be stacked in place within the same footprint up to current layerdepth
151 33
                $stackableDepth = $this->layerDepth - $orientatedItem->getDepth();
152 33
                $this->tryAndStackItemsIntoSpace($packedItems, $prevItem, $nextItem, $orientatedItem->getWidth(), $orientatedItem->getLength(), $stackableDepth);
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154 33
                $prevItem = $orientatedItem;
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156 33
                if ($this->items->isEmpty()) {
157 33
                    $this->usedDepth += $this->layerDepth;
158
                }
159
            } else {
160
161 25
                $prevItem = null;
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163 25
                if ($this->widthLeft >= min($itemToPack->getWidth(), $itemToPack->getLength()) && $this->isLayerStarted()) {
164 24
                    $this->logger->debug("No more fit in lengthwise, resetting for new row");
165 24
                    $this->lengthLeft += $this->layerLength;
166 24
                    $this->widthLeft -= $this->layerWidth;
167 24
                    $this->layerWidth = $this->layerLength = 0;
168 24
                    $this->items->insert($itemToPack);
169 24
                    continue;
170 19
                } elseif ($this->lengthLeft < min($itemToPack->getWidth(), $itemToPack->getLength()) || $this->layerDepth == 0) {
171 8
                    $this->logger->debug("doesn't fit on layer even when empty");
172 8
                    $this->usedDepth += $this->layerDepth;
173 8
                    continue;
174
                }
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176 17
                $this->widthLeft = $this->layerWidth ? min(floor($this->layerWidth * 1.1), $this->box->getInnerWidth()) : $this->box->getInnerWidth();
177 17
                $this->lengthLeft = $this->layerLength ? min(floor($this->layerLength * 1.1), $this->box->getInnerLength()) : $this->box->getInnerLength();
178 17
                $this->depthLeft -= $this->layerDepth;
179 17
                $this->usedDepth += $this->layerDepth;
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181 17
                $this->layerWidth = $this->layerLength = $this->layerDepth = 0;
182 17
                $this->logger->debug("doesn't fit, so starting next vertical layer");
183 17
                $this->items->insert($itemToPack);
184
            }
185
        }
186 33
        $this->logger->debug("done with this box");
187 33
        return new PackedBox(
188 33
            $this->box,
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            $packedItems,
190 33
            $this->widthLeft,
191 33
            $this->lengthLeft,
192 33
            $this->depthLeft,
193 33
            $this->remainingWeight,
194 33
            $this->usedWidth,
195 33
            $this->usedLength,
196 33
            $this->usedDepth);
197
    }
198
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    /**
200
     * @param Item $itemToPack
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     * @param OrientatedItem|null $prevItem
202
     * @param Item|null $nextItem
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     * @param int $maxWidth
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     * @param int $maxLength
205
     * @param int $maxDepth
206
     *
207
     * @return OrientatedItem|false
208
     */
209 33
    protected function getOrientationForItem(
210
        Item $itemToPack,
211
        OrientatedItem $prevItem = null,
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        Item $nextItem = null,
213
        $maxWidth, $maxLength,
214
        $maxDepth
215
    ) {
216 33
        $this->logger->debug(
217 33
            "evaluating item {$itemToPack->getDescription()} for fit",
218
            [
219 33
                'item' => $itemToPack,
220
                'space' => [
221 33
                    'maxWidth'    => $maxWidth,
222 33
                    'maxLength'   => $maxLength,
223 33
                    'maxDepth'    => $maxDepth,
224 33
                    'layerWidth'  => $this->layerWidth,
225 33
                    'layerLength' => $this->layerLength,
226 33
                    'layerDepth'  => $this->layerDepth
227
                ]
228
            ]
229
        );
230
231 33
        $orientatedItemFactory = new OrientatedItemFactory();
232 33
        $orientatedItemFactory->setLogger($this->logger);
233 33
        $orientatedItem = $orientatedItemFactory->getBestOrientation($this->box, $itemToPack, $prevItem, $nextItem, $maxWidth, $maxLength, $maxDepth);
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235 33
        return $orientatedItem;
236
    }
237
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    /**
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     * Figure out if we can stack the next item vertically on top of this rather than side by side
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     * Used when we've packed a tall item, and have just put a shorter one next to it
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     *
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     * @param ItemList       $packedItems
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     * @param OrientatedItem $prevItem
0 ignored issues
show
Documentation introduced by Doug Wright
Should the type for parameter $prevItem not be null|OrientatedItem?

This check looks for @param annotations where the type inferred by our type inference engine differs from the declared type.

It makes a suggestion as to what type it considers more descriptive.

Most often this is a case of a parameter that can be null in addition to its declared types.

Loading history...
244
     * @param Item           $nextItem
0 ignored issues
show
Documentation introduced by Doug Wright
Should the type for parameter $nextItem not be null|Item?

This check looks for @param annotations where the type inferred by our type inference engine differs from the declared type.

It makes a suggestion as to what type it considers more descriptive.

Most often this is a case of a parameter that can be null in addition to its declared types.

Loading history...
245
     * @param int            $maxWidth
246
     * @param int            $maxLength
247
     * @param int            $maxDepth
248
     */
249 33
    protected function tryAndStackItemsIntoSpace(
250
        ItemList $packedItems,
251
        OrientatedItem $prevItem = null,
252
        Item $nextItem = null,
253
        $maxWidth,
254
        $maxLength,
255
        $maxDepth
256
    ) {
257 33
        while (!$this->items->isEmpty() && $this->remainingWeight >= $this->items->top()->getWeight()) {
258 31
            $stackedItem = $this->getOrientationForItem(
259 31
                $this->items->top(),
260
                $prevItem,
261
                $nextItem,
262
                $maxWidth,
263
                $maxLength,
264
                $maxDepth
265
            );
266 31
            if ($stackedItem) {
267 3
                $this->remainingWeight -= $this->items->top()->getWeight();
268 3
                $maxDepth -= $stackedItem->getDepth();
269 3
                $packedItems->insert($this->items->extract());
270
            } else {
271 31
                break;
272
            }
273
        }
274
    }
275
276
    /**
277
     * @return bool
278
     */
279 25
    protected function isLayerStarted()
280
    {
281 25
        return $this->layerWidth > 0 && $this->layerLength > 0 && $this->layerDepth > 0;
282
    }
283
284
    /**
285
     * As well as purely dimensional constraints, there are other constraints that need to be met
286
     * e.g. weight limits or item-specific restrictions (e.g. max <x> batteries per box)
287
     *
288
     * @param Item     $itemToPack
289
     * @param ItemList $packedItems
290
     *
291
     * @return bool
292
     */
293 33
    protected function checkNonDimensionalConstraints(Item $itemToPack, ItemList $packedItems)
294
    {
295 33
        $weightOK = $itemToPack->getWeight() <= $this->remainingWeight;
296
297 33
        if ($itemToPack instanceof ConstrainedItem) {
298 1
            return $weightOK && $itemToPack->canBePackedInBox(clone $packedItems, $this->box);
299
        }
300
301 32
        return $weightOK;
302
    }
303
}
304