<?php
namespace Illuminate\Support;
use ArrayIterator;
use Closure;
use DateTimeInterface;
use Illuminate\Support\Traits\EnumeratesValues;
use Illuminate\Support\Traits\Macroable;
use IteratorAggregate;
use stdClass;
class LazyCollection implements Enumerable
{
use EnumeratesValues, Macroable;
/**
* The source from which to generate items.
*
* @var callable|static
*/
public $source;
/**
* Create a new lazy collection instance.
*
* @param mixed $source
* @return void
*/
public function __construct($source = null)
{
if ($source instanceof Closure || $source instanceof self) {
$this->source = $source;
} elseif (is_null($source)) {
$this->source = static::empty();
} else {
$this->source = $this->getArrayableItems($source);
}
}
/**
* Create a collection with the given range.
*
* @param int $from
* @param int $to
* @return static
*/
public static function range($from, $to)
{
return new static(function () use ($from, $to) {
if ($from <= $to) {
for (; $from <= $to; $from++) {
yield $from;
}
} else {
for (; $from >= $to; $from--) {
yield $from;
}
}
});
}
/**
* Get all items in the enumerable.
*
* @return array
*/
public function all()
{
if (is_array($this->source)) {
return $this->source;
}
return iterator_to_array($this->getIterator());
}
/**
* Eager load all items into a new lazy collection backed by an array.
*
* @return static
*/
public function eager()
{
return new static($this->all());
}
/**
* Cache values as they're enumerated.
*
* @return static
*/
public function remember()
{
$iterator = $this->getIterator();
$iteratorIndex = 0;
$cache = [];
return new static(function () use ($iterator, &$iteratorIndex, &$cache) {
for ($index = 0; true; $index++) {
if (array_key_exists($index, $cache)) {
yield $cache[$index][0] => $cache[$index][1];
continue;
}
if ($iteratorIndex < $index) {
$iterator->next();
$iteratorIndex++;
}
if (! $iterator->valid()) {
break;
}
$cache[$index] = [$iterator->key(), $iterator->current()];
yield $cache[$index][0] => $cache[$index][1];
}
});
}
/**
* Get the average value of a given key.
*
* @param callable|string|null $callback
* @return mixed
*/
public function avg($callback = null)
{
return $this->collect()->avg($callback);
}
/**
* Get the median of a given key.
*
* @param string|array|null $key
* @return mixed
*/
public function median($key = null)
{
return $this->collect()->median($key);
}
/**
* Get the mode of a given key.
*
* @param string|array|null $key
* @return array|null
*/
public function mode($key = null)
{
return $this->collect()->mode($key);
}
/**
* Collapse the collection of items into a single array.
*
* @return static
*/
public function collapse()
{
return new static(function () {
foreach ($this as $values) {
if (is_array($values) || $values instanceof Enumerable) {
foreach ($values as $value) {
yield $value;
}
}
}
});
}
/**
* Determine if an item exists in the enumerable.
*
* @param mixed $key
* @param mixed $operator
* @param mixed $value
* @return bool
*/
public function contains($key, $operator = null, $value = null)
{
if (func_num_args() === 1 && $this->useAsCallable($key)) {
$placeholder = new stdClass;
return $this->first($key, $placeholder) !== $placeholder;
}
if (func_num_args() === 1) {
$needle = $key;
foreach ($this as $value) {
if ($value == $needle) {
return true;
}
}
return false;
}
return $this->contains($this->operatorForWhere(...func_get_args()));
}
/**
* Cross join the given iterables, returning all possible permutations.
*
* @param array ...$arrays
* @return static
*/
public function crossJoin(...$arrays)
{
return $this->passthru('crossJoin', func_get_args());
}
/**
* Count the number of items in the collection by a field or using a callback.
*
* @param callable|string $countBy
* @return static
*/
public function countBy($countBy = null)
{
$countBy = is_null($countBy)
? $this->identity()
: $this->valueRetriever($countBy);
return new static(function () use ($countBy) {
$counts = [];
foreach ($this as $key => $value) {
$group = $countBy($value, $key);
if (empty($counts[$group])) {
$counts[$group] = 0;
}
$counts[$group]++;
}
yield from $counts;
});
}
/**
* Get the items that are not present in the given items.
*
* @param mixed $items
* @return static
*/
public function diff($items)
{
return $this->passthru('diff', func_get_args());
}
/**
* Get the items that are not present in the given items, using the callback.
*
* @param mixed $items
* @param callable $callback
* @return static
*/
public function diffUsing($items, callable $callback)
{
return $this->passthru('diffUsing', func_get_args());
}
/**
* Get the items whose keys and values are not present in the given items.
*
* @param mixed $items
* @return static
*/
public function diffAssoc($items)
{
return $this->passthru('diffAssoc', func_get_args());
}
/**
* Get the items whose keys and values are not present in the given items, using the callback.
*
* @param mixed $items
* @param callable $callback
* @return static
*/
public function diffAssocUsing($items, callable $callback)
{
return $this->passthru('diffAssocUsing', func_get_args());
}
/**
* Get the items whose keys are not present in the given items.
*
* @param mixed $items
* @return static
*/
public function diffKeys($items)
{
return $this->passthru('diffKeys', func_get_args());
}
/**
* Get the items whose keys are not present in the given items, using the callback.
*
* @param mixed $items
* @param callable $callback
* @return static
*/
public function diffKeysUsing($items, callable $callback)
{
return $this->passthru('diffKeysUsing', func_get_args());
}
/**
* Retrieve duplicate items.
*
* @param callable|null $callback
* @param bool $strict
* @return static
*/
public function duplicates($callback = null, $strict = false)
{
return $this->passthru('duplicates', func_get_args());
}
/**
* Retrieve duplicate items using strict comparison.
*
* @param callable|null $callback
* @return static
*/
public function duplicatesStrict($callback = null)
{
return $this->passthru('duplicatesStrict', func_get_args());
}
/**
* Get all items except for those with the specified keys.
*
* @param mixed $keys
* @return static
*/
public function except($keys)
{
return $this->passthru('except', func_get_args());
}
/**
* Run a filter over each of the items.
*
* @param callable|null $callback
* @return static
*/
public function filter(callable $callback = null)
{
if (is_null($callback)) {
$callback = function ($value) {
return (bool) $value;
};
}
return new static(function () use ($callback) {
foreach ($this as $key => $value) {
if ($callback($value, $key)) {
yield $key => $value;
}
}
});
}
/**
* Get the first item from the enumerable passing the given truth test.
*
* @param callable|null $callback
* @param mixed $default
* @return mixed
*/
public function first(callable $callback = null, $default = null)
{
$iterator = $this->getIterator();
if (is_null($callback)) {
if (! $iterator->valid()) {
return value($default);
}
return $iterator->current();
}
foreach ($iterator as $key => $value) {
if ($callback($value, $key)) {
return $value;
}
}
return value($default);
}
/**
* Get a flattened list of the items in the collection.
*
* @param int $depth
* @return static
*/
public function flatten($depth = INF)
{
$instance = new static(function () use ($depth) {
foreach ($this as $item) {
if (! is_array($item) && ! $item instanceof Enumerable) {
yield $item;
} elseif ($depth === 1) {
yield from $item;
} else {
yield from (new static($item))->flatten($depth - 1);
}
}
});
return $instance->values();
}
/**
* Flip the items in the collection.
*
* @return static
*/
public function flip()
{
return new static(function () {
foreach ($this as $key => $value) {
yield $value => $key;
}
});
}
/**
* Get an item by key.
*
* @param mixed $key
* @param mixed $default
* @return mixed
*/
public function get($key, $default = null)
{
if (is_null($key)) {
return;
}
foreach ($this as $outerKey => $outerValue) {
if ($outerKey == $key) {
return $outerValue;
}
}
return value($default);
}
/**
* Group an associative array by a field or using a callback.
*
* @param array|callable|string $groupBy
* @param bool $preserveKeys
* @return static
*/
public function groupBy($groupBy, $preserveKeys = false)
{
return $this->passthru('groupBy', func_get_args());
}
/**
* Key an associative array by a field or using a callback.
*
* @param callable|string $keyBy
* @return static
*/
public function keyBy($keyBy)
{
return new static(function () use ($keyBy) {
$keyBy = $this->valueRetriever($keyBy);
foreach ($this as $key => $item) {
$resolvedKey = $keyBy($item, $key);
if (is_object($resolvedKey)) {
$resolvedKey = (string) $resolvedKey;
}
yield $resolvedKey => $item;
}
});
}
/**
* Determine if an item exists in the collection by key.
*
* @param mixed $key
* @return bool
*/
public function has($key)
{
$keys = array_flip(is_array($key) ? $key : func_get_args());
$count = count($keys);
foreach ($this as $key => $value) {
if (array_key_exists($key, $keys) && --$count == 0) {
return true;
}
}
return false;
}
/**
* Concatenate values of a given key as a string.
*
* @param string $value
* @param string|null $glue
* @return string
*/
public function implode($value, $glue = null)
{
return $this->collect()->implode(...func_get_args());
}
/**
* Intersect the collection with the given items.
*
* @param mixed $items
* @return static
*/
public function intersect($items)
{
return $this->passthru('intersect', func_get_args());
}
/**
* Intersect the collection with the given items by key.
*
* @param mixed $items
* @return static
*/
public function intersectByKeys($items)
{
return $this->passthru('intersectByKeys', func_get_args());
}
/**
* Determine if the items are empty or not.
*
* @return bool
*/
public function isEmpty()
{
return ! $this->getIterator()->valid();
}
/**
* Determine if the collection contains a single item.
*
* @return bool
*/
public function containsOneItem()
{
return $this->take(2)->count() === 1;
}
/**
* Join all items from the collection using a string. The final items can use a separate glue string.
*
* @param string $glue
* @param string $finalGlue
* @return string
*/
public function join($glue, $finalGlue = '')
{
return $this->collect()->join(...func_get_args());
}
/**
* Get the keys of the collection items.
*
* @return static
*/
public function keys()
{
return new static(function () {
foreach ($this as $key => $value) {
yield $key;
}
});
}
/**
* Get the last item from the collection.
*
* @param callable|null $callback
* @param mixed $default
* @return mixed
*/
public function last(callable $callback = null, $default = null)
{
$needle = $placeholder = new stdClass;
foreach ($this as $key => $value) {
if (is_null($callback) || $callback($value, $key)) {
$needle = $value;
}
}
return $needle === $placeholder ? value($default) : $needle;
}
/**
* Get the values of a given key.
*
* @param string|array $value
* @param string|null $key
* @return static
*/
public function pluck($value, $key = null)
{
return new static(function () use ($value, $key) {
[$value, $key] = $this->explodePluckParameters($value, $key);
foreach ($this as $item) {
$itemValue = data_get($item, $value);
if (is_null($key)) {
yield $itemValue;
} else {
$itemKey = data_get($item, $key);
if (is_object($itemKey) && method_exists($itemKey, '__toString')) {
$itemKey = (string) $itemKey;
}
yield $itemKey => $itemValue;
}
}
});
}
/**
* Run a map over each of the items.
*
* @param callable $callback
* @return static
*/
public function map(callable $callback)
{
return new static(function () use ($callback) {
foreach ($this as $key => $value) {
yield $key => $callback($value, $key);
}
});
}
/**
* Run a dictionary map over the items.
*
* The callback should return an associative array with a single key/value pair.
*
* @param callable $callback
* @return static
*/
public function mapToDictionary(callable $callback)
{
return $this->passthru('mapToDictionary', func_get_args());
}
/**
* Run an associative map over each of the items.
*
* The callback should return an associative array with a single key/value pair.
*
* @param callable $callback
* @return static
*/
public function mapWithKeys(callable $callback)
{
return new static(function () use ($callback) {
foreach ($this as $key => $value) {
yield from $callback($value, $key);
}
});
}
/**
* Merge the collection with the given items.
*
* @param mixed $items
* @return static
*/
public function merge($items)
{
return $this->passthru('merge', func_get_args());
}
/**
* Recursively merge the collection with the given items.
*
* @param mixed $items
* @return static
*/
public function mergeRecursive($items)
{
return $this->passthru('mergeRecursive', func_get_args());
}
/**
* Create a collection by using this collection for keys and another for its values.
*
* @param mixed $values
* @return static
*/
public function combine($values)
{
return new static(function () use ($values) {
$values = $this->makeIterator($values);
$errorMessage = 'Both parameters should have an equal number of elements';
foreach ($this as $key) {
if (! $values->valid()) {
trigger_error($errorMessage, E_USER_WARNING);
break;
}
yield $key => $values->current();
$values->next();
}
if ($values->valid()) {
trigger_error($errorMessage, E_USER_WARNING);
}
});
}
/**
* Union the collection with the given items.
*
* @param mixed $items
* @return static
*/
public function union($items)
{
return $this->passthru('union', func_get_args());
}
/**
* Create a new collection consisting of every n-th element.
*
* @param int $step
* @param int $offset
* @return static
*/
public function nth($step, $offset = 0)
{
return new static(function () use ($step, $offset) {
$position = 0;
foreach ($this as $item) {
if ($position % $step === $offset) {
yield $item;
}
$position++;
}
});
}
/**
* Get the items with the specified keys.
*
* @param mixed $keys
* @return static
*/
public function only($keys)
{
if ($keys instanceof Enumerable) {
$keys = $keys->all();
} elseif (! is_null($keys)) {
$keys = is_array($keys) ? $keys : func_get_args();
}
return new static(function () use ($keys) {
if (is_null($keys)) {
yield from $this;
} else {
$keys = array_flip($keys);
foreach ($this as $key => $value) {
if (array_key_exists($key, $keys)) {
yield $key => $value;
unset($keys[$key]);
if (empty($keys)) {
break;
}
}
}
}
});
}
/**
* Push all of the given items onto the collection.
*
* @param iterable $source
* @return static
*/
public function concat($source)
{
return (new static(function () use ($source) {
yield from $this;
yield from $source;
}))->values();
}
/**
* Get one or a specified number of items randomly from the collection.
*
* @param int|null $number
* @return static|mixed
*
* @throws \InvalidArgumentException
*/
public function random($number = null)
{
$result = $this->collect()->random(...func_get_args());
return is_null($number) ? $result : new static($result);
}
/**
* Replace the collection items with the given items.
*
* @param mixed $items
* @return static
*/
public function replace($items)
{
return new static(function () use ($items) {
$items = $this->getArrayableItems($items);
foreach ($this as $key => $value) {
if (array_key_exists($key, $items)) {
yield $key => $items[$key];
unset($items[$key]);
} else {
yield $key => $value;
}
}
foreach ($items as $key => $value) {
yield $key => $value;
}
});
}
/**
* Recursively replace the collection items with the given items.
*
* @param mixed $items
* @return static
*/
public function replaceRecursive($items)
{
return $this->passthru('replaceRecursive', func_get_args());
}
/**
* Reverse items order.
*
* @return static
*/
public function reverse()
{
return $this->passthru('reverse', func_get_args());
}
/**
* Search the collection for a given value and return the corresponding key if successful.
*
* @param mixed $value
* @param bool $strict
* @return mixed
*/
public function search($value, $strict = false)
{
$predicate = $this->useAsCallable($value)
? $value
: function ($item) use ($value, $strict) {
return $strict ? $item === $value : $item == $value;
};
foreach ($this as $key => $item) {
if ($predicate($item, $key)) {
return $key;
}
}
return false;
}
/**
* Shuffle the items in the collection.
*
* @param int|null $seed
* @return static
*/
public function shuffle($seed = null)
{
return $this->passthru('shuffle', func_get_args());
}
/**
* Skip the first {$count} items.
*
* @param int $count
* @return static
*/
public function skip($count)
{
return new static(function () use ($count) {
$iterator = $this->getIterator();
while ($iterator->valid() && $count--) {
$iterator->next();
}
while ($iterator->valid()) {
yield $iterator->key() => $iterator->current();
$iterator->next();
}
});
}
/**
* Skip items in the collection until the given condition is met.
*
* @param mixed $value
* @return static
*/
public function skipUntil($value)
{
$callback = $this->useAsCallable($value) ? $value : $this->equality($value);
return $this->skipWhile($this->negate($callback));
}
/**
* Skip items in the collection while the given condition is met.
*
* @param mixed $value
* @return static
*/
public function skipWhile($value)
{
$callback = $this->useAsCallable($value) ? $value : $this->equality($value);
return new static(function () use ($callback) {
$iterator = $this->getIterator();
while ($iterator->valid() && $callback($iterator->current(), $iterator->key())) {
$iterator->next();
}
while ($iterator->valid()) {
yield $iterator->key() => $iterator->current();
$iterator->next();
}
});
}
/**
* Get a slice of items from the enumerable.
*
* @param int $offset
* @param int|null $length
* @return static
*/
public function slice($offset, $length = null)
{
if ($offset < 0 || $length < 0) {
return $this->passthru('slice', func_get_args());
}
$instance = $this->skip($offset);
return is_null($length) ? $instance : $instance->take($length);
}
/**
* Split a collection into a certain number of groups.
*
* @param int $numberOfGroups
* @return static
*/
public function split($numberOfGroups)
{
return $this->passthru('split', func_get_args());
}
/**
* Chunk the collection into chunks of the given size.
*
* @param int $size
* @return static
*/
public function chunk($size)
{
if ($size <= 0) {
return static::empty();
}
return new static(function () use ($size) {
$iterator = $this->getIterator();
while ($iterator->valid()) {
$chunk = [];
while (true) {
$chunk[$iterator->key()] = $iterator->current();
if (count($chunk) < $size) {
$iterator->next();
if (! $iterator->valid()) {
break;
}
} else {
break;
}
}
yield new static($chunk);
$iterator->next();
}
});
}
/**
* Split a collection into a certain number of groups, and fill the first groups completely.
*
* @param int $numberOfGroups
* @return static
*/
public function splitIn($numberOfGroups)
{
return $this->chunk(ceil($this->count() / $numberOfGroups));
}
/**
* Chunk the collection into chunks with a callback.
*
* @param callable $callback
* @return static
*/
public function chunkWhile(callable $callback)
{
return new static(function () use ($callback) {
$iterator = $this->getIterator();
$chunk = new Collection;
if ($iterator->valid()) {
$chunk[$iterator->key()] = $iterator->current();
$iterator->next();
}
while ($iterator->valid()) {
if (! $callback($iterator->current(), $iterator->key(), $chunk)) {
yield new static($chunk);
$chunk = new Collection;
}
$chunk[$iterator->key()] = $iterator->current();
$iterator->next();
}
if ($chunk->isNotEmpty()) {
yield new static($chunk);
}
});
}
/**
* Sort through each item with a callback.
*
* @param callable|null|int $callback
* @return static
*/
public function sort($callback = null)
{
return $this->passthru('sort', func_get_args());
}
/**
* Sort items in descending order.
*
* @param int $options
* @return static
*/
public function sortDesc($options = SORT_REGULAR)
{
return $this->passthru('sortDesc', func_get_args());
}
/**
* Sort the collection using the given callback.
*
* @param callable|string $callback
* @param int $options
* @param bool $descending
* @return static
*/
public function sortBy($callback, $options = SORT_REGULAR, $descending = false)
{
return $this->passthru('sortBy', func_get_args());
}
/**
* Sort the collection in descending order using the given callback.
*
* @param callable|string $callback
* @param int $options
* @return static
*/
public function sortByDesc($callback, $options = SORT_REGULAR)
{
return $this->passthru('sortByDesc', func_get_args());
}
/**
* Sort the collection keys.
*
* @param int $options
* @param bool $descending
* @return static
*/
public function sortKeys($options = SORT_REGULAR, $descending = false)
{
return $this->passthru('sortKeys', func_get_args());
}
/**
* Sort the collection keys in descending order.
*
* @param int $options
* @return static
*/
public function sortKeysDesc($options = SORT_REGULAR)
{
return $this->passthru('sortKeysDesc', func_get_args());
}
/**
* Take the first or last {$limit} items.
*
* @param int $limit
* @return static
*/
public function take($limit)
{
if ($limit < 0) {
return $this->passthru('take', func_get_args());
}
return new static(function () use ($limit) {
$iterator = $this->getIterator();
while ($limit--) {
if (! $iterator->valid()) {
break;
}
yield $iterator->key() => $iterator->current();
if ($limit) {
$iterator->next();
}
}
});
}
/**
* Take items in the collection until the given condition is met.
*
* @param mixed $value
* @return static
*/
public function takeUntil($value)
{
$callback = $this->useAsCallable($value) ? $value : $this->equality($value);
return new static(function () use ($callback) {
foreach ($this as $key => $item) {
if ($callback($item, $key)) {
break;
}
yield $key => $item;
}
});
}
/**
* Take items in the collection until a given point in time.
*
* @param \DateTimeInterface $timeout
* @return static
*/
public function takeUntilTimeout(DateTimeInterface $timeout)
{
$timeout = $timeout->getTimestamp();
return $this->takeWhile(function () use ($timeout) {
return $this->now() < $timeout;
});
}
/**
* Take items in the collection while the given condition is met.
*
* @param mixed $value
* @return static
*/
public function takeWhile($value)
{
$callback = $this->useAsCallable($value) ? $value : $this->equality($value);
return $this->takeUntil(function ($item, $key) use ($callback) {
return ! $callback($item, $key);
});
}
/**
* Pass each item in the collection to the given callback, lazily.
*
* @param callable $callback
* @return static
*/
public function tapEach(callable $callback)
{
return new static(function () use ($callback) {
foreach ($this as $key => $value) {
$callback($value, $key);
yield $key => $value;
}
});
}
/**
* Reset the keys on the underlying array.
*
* @return static
*/
public function values()
{
return new static(function () {
foreach ($this as $item) {
yield $item;
}
});
}
/**
* Zip the collection together with one or more arrays.
*
* e.g. new LazyCollection([1, 2, 3])->zip([4, 5, 6]);
* => [[1, 4], [2, 5], [3, 6]]
*
* @param mixed ...$items
* @return static
*/
public function zip($items)
{
$iterables = func_get_args();
return new static(function () use ($iterables) {
$iterators = Collection::make($iterables)->map(function ($iterable) {
return $this->makeIterator($iterable);
})->prepend($this->getIterator());
while ($iterators->contains->valid()) {
yield new static($iterators->map->current());
$iterators->each->next();
}
});
}
/**
* Pad collection to the specified length with a value.
*
* @param int $size
* @param mixed $value
* @return static
*/
public function pad($size, $value)
{
if ($size < 0) {
return $this->passthru('pad', func_get_args());
}
return new static(function () use ($size, $value) {
$yielded = 0;
foreach ($this as $index => $item) {
yield $index => $item;
$yielded++;
}
while ($yielded++ < $size) {
yield $value;
}
});
}
/**
* Get the values iterator.
*
* @return \Traversable
*/
public function getIterator()
{
return $this->makeIterator($this->source);
}
/**
* Count the number of items in the collection.
*
* @return int
*/
public function count()
{
if (is_array($this->source)) {
return count($this->source);
}
return iterator_count($this->getIterator());
}
/**
* Make an iterator from the given source.
*
* @param mixed $source
* @return \Traversable
*/
protected function makeIterator($source)
{
if ($source instanceof IteratorAggregate) {
return $source->getIterator();
}
if (is_array($source)) {
return new ArrayIterator($source);
}
return $source();
}
/**
* Explode the "value" and "key" arguments passed to "pluck".
*
* @param string|array $value
* @param string|array|null $key
* @return array
*/
protected function explodePluckParameters($value, $key)
{
$value = is_string($value) ? explode('.', $value) : $value;
$key = is_null($key) || is_array($key) ? $key : explode('.', $key);
return [$value, $key];
}
/**
* Pass this lazy collection through a method on the collection class.
*
* @param string $method
* @param array $params
* @return static
*/
protected function passthru($method, array $params)
{
return new static(function () use ($method, $params) {
yield from $this->collect()->$method(...$params);
});
}
/**
* Get the current time.
*
* @return int
*/
protected function now()
{
return time();
}
}