Query.php

<?php
/**
 * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
 * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 *
 * Licensed under The MIT License
 * For full copyright and license information, please see the LICENSE.txt
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 * @link          https://cakephp.org CakePHP(tm) Project
 * @since         3.0.0
 * @license       https://opensource.org/licenses/mit-license.php MIT License
 */
namespace Cake\ORM;

use ArrayObject;
use Cake\Database\ExpressionInterface;
use Cake\Database\Query as DatabaseQuery;
use Cake\Database\TypedResultInterface;
use Cake\Database\TypeMap;
use Cake\Database\ValueBinder;
use Cake\Datasource\QueryInterface;
use Cake\Datasource\QueryTrait;
use JsonSerializable;
use RuntimeException;

/**
 * Extends the base Query class to provide new methods related to association
 * loading, automatic fields selection, automatic type casting and to wrap results
 * into a specific iterator that will be responsible for hydrating results if
 * required.
 *
 * @see \Cake\Collection\CollectionInterface For a full description of the collection methods supported by this class
 * @method \Cake\Collection\CollectionInterface each(callable $c) Passes each of the query results to the callable
 * @method \Cake\Collection\CollectionInterface filter(callable $c = null) Keeps the results using passing the callable test
 * @method \Cake\Collection\CollectionInterface reject(callable $c) Removes the results passing the callable test
 * @method bool every(callable $c) Returns true if all the results pass the callable test
 * @method bool some(callable $c) Returns true if at least one of the results pass the callable test
 * @method \Cake\Collection\CollectionInterface map(callable $c) Modifies each of the results using the callable
 * @method mixed reduce(callable $c, $zero = null) Folds all the results into a single value using the callable.
 * @method \Cake\Collection\CollectionInterface extract($field) Extracts a single column from each row
 * @method mixed max($field, $type = SORT_NUMERIC) Returns the maximum value for a single column in all the results.
 * @method mixed min($field, $type = SORT_NUMERIC) Returns the minimum value for a single column in all the results.
 * @method \Cake\Collection\CollectionInterface groupBy(string|callable $field) In-memory group all results by the value of a column.
 * @method \Cake\Collection\CollectionInterface indexBy(string|callable $field) Returns the results indexed by the value of a column.
 * @method int countBy(string|callable $field) Returns the number of unique values for a column
 * @method float sumOf(string|callable $field) Returns the sum of all values for a single column
 * @method \Cake\Collection\CollectionInterface shuffle() In-memory randomize the order the results are returned
 * @method \Cake\Collection\CollectionInterface sample($size = 10) In-memory shuffle the results and return a subset of them.
 * @method \Cake\Collection\CollectionInterface take($size = 1, $from = 0) In-memory limit and offset for the query results.
 * @method \Cake\Collection\CollectionInterface skip(int $howMany) Skips some rows from the start of the query result.
 * @method mixed last() Return the last row of the query result
 * @method \Cake\Collection\CollectionInterface append(array|\Traversable $items) Appends more rows to the result of the query.
 * @method \Cake\Collection\CollectionInterface combine($k, $v, $g = null) Returns the values of the column $v index by column $k,
 *   and grouped by $g.
 * @method \Cake\Collection\CollectionInterface nest($k, $p, $n = 'children') Creates a tree structure by nesting the values of column $p into that
 *   with the same value for $k using $n as the nesting key.
 * @method array toArray() Returns a key-value array with the results of this query.
 * @method array toList() Returns a numerically indexed array with the results of this query.
 * @method \Cake\Collection\CollectionInterface stopWhen(callable $c) Returns each row until the callable returns true.
 * @method \Cake\Collection\CollectionInterface zip(array|\Traversable $c) Returns the first result of both the query and $c in an array,
 *   then the second results and so on.
 * @method \Cake\Collection\CollectionInterface zipWith($collections, callable $callable) Returns each of the results out of calling $c
 *   with the first rows of the query and each of the items, then the second rows and so on.
 * @method \Cake\Collection\CollectionInterface chunk($size) Groups the results in arrays of $size rows each.
 * @method bool isEmpty() Returns true if this query found no results.
 * @mixin \Cake\Datasource\QueryTrait
 */
class Query extends DatabaseQuery implements JsonSerializable, QueryInterface
{

    use QueryTrait {
        cache as private _cache;
        all as private _all;
        _decorateResults as private _applyDecorators;
        __call as private _call;
    }

    /**
     * Indicates that the operation should append to the list
     *
     * @var int
     */
    const APPEND = 0;

    /**
     * Indicates that the operation should prepend to the list
     *
     * @var int
     */
    const PREPEND = 1;

    /**
     * Indicates that the operation should overwrite the list
     *
     * @var bool
     */
    const OVERWRITE = true;

    /**
     * Whether the user select any fields before being executed, this is used
     * to determined if any fields should be automatically be selected.
     *
     * @var bool
     */
    protected $_hasFields;

    /**
     * Tracks whether or not the original query should include
     * fields from the top level table.
     *
     * @var bool
     */
    protected $_autoFields;

    /**
     * Whether to hydrate results into entity objects
     *
     * @var bool
     */
    protected $_hydrate = true;

    /**
     * A callable function that can be used to calculate the total amount of
     * records this query will match when not using `limit`
     *
     * @var callable
     */
    protected $_counter;

    /**
     * Instance of a class responsible for storing association containments and
     * for eager loading them when this query is executed
     *
     * @var \Cake\ORM\EagerLoader
     */
    protected $_eagerLoader;

    /**
     * True if the beforeFind event has already been triggered for this query
     *
     * @var bool
     */
    protected $_beforeFindFired = false;

    /**
     * The COUNT(*) for the query.
     *
     * When set, count query execution will be bypassed.
     *
     * @var int|null
     */
    protected $_resultsCount;

    /**
     * Constructor
     *
     * @param \Cake\Database\Connection $connection The connection object
     * @param \Cake\ORM\Table $table The table this query is starting on
     */
    public function __construct($connection, $table)
    {
        parent::__construct($connection);
        $this->repository($table);

        if ($this->_repository) {
            $this->addDefaultTypes($this->_repository);
        }
    }

    /**
     * {@inheritDoc}
     *
     * If you pass an instance of a `Cake\ORM\Table` or `Cake\ORM\Association` class,
     * all the fields in the schema of the table or the association will be added to
     * the select clause.
     *
     * @param array|\Cake\Database\ExpressionInterface|string|\Cake\ORM\Table|\Cake\ORM\Association $fields fields
     * to be added to the list.
     * @param bool $overwrite whether to reset fields with passed list or not
     * @return $this
     */
    public function select($fields = [], $overwrite = false)
    {
        if ($fields instanceof Association) {
            $fields = $fields->getTarget();
        }

        if ($fields instanceof Table) {
            $fields = $this->aliasFields($fields->getSchema()->columns(), $fields->getAlias());
        }

        return parent::select($fields, $overwrite);
    }

    /**
     * Hints this object to associate the correct types when casting conditions
     * for the database. This is done by extracting the field types from the schema
     * associated to the passed table object. This prevents the user from repeating
     * themselves when specifying conditions.
     *
     * This method returns the same query object for chaining.
     *
     * @param \Cake\ORM\Table $table The table to pull types from
     * @return $this
     */
    public function addDefaultTypes(Table $table)
    {
        $alias = $table->getAlias();
        $map = $table->getSchema()->typeMap();
        $fields = [];
        foreach ($map as $f => $type) {
            $fields[$f] = $fields[$alias . '.' . $f] = $fields[$alias . '__' . $f] = $type;
        }
        $this->getTypeMap()->addDefaults($fields);

        return $this;
    }

    /**
     * Sets the instance of the eager loader class to use for loading associations
     * and storing containments.
     *
     * @param \Cake\ORM\EagerLoader $instance The eager loader to use.
     * @return $this
     */
    public function setEagerLoader(EagerLoader $instance)
    {
        $this->_eagerLoader = $instance;

        return $this;
    }

    /**
     * Returns the currently configured instance.
     *
     * @return \Cake\ORM\EagerLoader
     */
    public function getEagerLoader()
    {
        if ($this->_eagerLoader === null) {
            $this->_eagerLoader = new EagerLoader();
        }

        return $this->_eagerLoader;
    }

    /**
     * Sets the instance of the eager loader class to use for loading associations
     * and storing containments. If called with no arguments, it will return the
     * currently configured instance.
     *
     * @deprecated 3.4.0 Use setEagerLoader()/getEagerLoader() instead.
     * @param \Cake\ORM\EagerLoader|null $instance The eager loader to use. Pass null
     *   to get the current eagerloader.
     * @return \Cake\ORM\EagerLoader|$this
     */
    public function eagerLoader(EagerLoader $instance = null)
    {
        deprecationWarning(
            'Query::eagerLoader() is deprecated. ' .
            'Use setEagerLoader()/getEagerLoader() instead.'
        );
        if ($instance !== null) {
            return $this->setEagerLoader($instance);
        }

        return $this->getEagerLoader();
    }

    /**
     * Sets the list of associations that should be eagerly loaded along with this
     * query. The list of associated tables passed must have been previously set as
     * associations using the Table API.
     *
     * ### Example:
     *
     * ```
     * // Bring articles' author information
     * $query->contain('Author');
     *
     * // Also bring the category and tags associated to each article
     * $query->contain(['Category', 'Tag']);
     * ```
     *
     * Associations can be arbitrarily nested using dot notation or nested arrays,
     * this allows this object to calculate joins or any additional queries that
     * must be executed to bring the required associated data.
     *
     * ### Example:
     *
     * ```
     * // Eager load the product info, and for each product load other 2 associations
     * $query->contain(['Product' => ['Manufacturer', 'Distributor']);
     *
     * // Which is equivalent to calling
     * $query->contain(['Products.Manufactures', 'Products.Distributors']);
     *
     * // For an author query, load his region, state and country
     * $query->contain('Regions.States.Countries');
     * ```
     *
     * It is possible to control the conditions and fields selected for each of the
     * contained associations:
     *
     * ### Example:
     *
     * ```
     * $query->contain(['Tags' => function ($q) {
     *     return $q->where(['Tags.is_popular' => true]);
     * }]);
     *
     * $query->contain(['Products.Manufactures' => function ($q) {
     *     return $q->select(['name'])->where(['Manufactures.active' => true]);
     * }]);
     * ```
     *
     * Each association might define special options when eager loaded, the allowed
     * options that can be set per association are:
     *
     * - `foreignKey`: Used to set a different field to match both tables, if set to false
     *   no join conditions will be generated automatically. `false` can only be used on
     *   joinable associations and cannot be used with hasMany or belongsToMany associations.
     * - `fields`: An array with the fields that should be fetched from the association.
     * - `finder`: The finder to use when loading associated records. Either the name of the
     *   finder as a string, or an array to define options to pass to the finder.
     * - `queryBuilder`: Equivalent to passing a callable instead of an options array.
     *
     * ### Example:
     *
     * ```
     * // Set options for the hasMany articles that will be eagerly loaded for an author
     * $query->contain([
     *     'Articles' => [
     *         'fields' => ['title', 'author_id']
     *     ]
     * ]);
     * ```
     *
     * Finders can be configured to use options.
     *
     * ```
     * // Retrieve translations for the articles, but only those for the `en` and `es` locales
     * $query->contain([
     *     'Articles' => [
     *         'finder' => [
     *             'translations' => [
     *                 'locales' => ['en', 'es']
     *             ]
     *         ]
     *     ]
     * ]);
     * ```
     *
     * When containing associations, it is important to include foreign key columns.
     * Failing to do so will trigger exceptions.
     *
     * ```
     * // Use a query builder to add conditions to the containment
     * $query->contain('Authors', function ($q) {
     *     return $q->where(...); // add conditions
     * });
     * // Use special join conditions for multiple containments in the same method call
     * $query->contain([
     *     'Authors' => [
     *         'foreignKey' => false,
     *         'queryBuilder' => function ($q) {
     *             return $q->where(...); // Add full filtering conditions
     *         }
     *     ],
     *     'Tags' => function ($q) {
     *         return $q->where(...); // add conditions
     *     }
     * ]);
     * ```
     *
     * If called with no arguments, this function will return an array with
     * with the list of previously configured associations to be contained in the
     * result.
     *
     * If called with an empty first argument and `$override` is set to true, the
     * previous list will be emptied.
     *
     * @param array|string|null $associations List of table aliases to be queried.
     * @param callable|bool $override The query builder for the association, or
     *   if associations is an array, a bool on whether to override previous list
     *   with the one passed
     * defaults to merging previous list with the new one.
     * @return array|$this
     */
    public function contain($associations = null, $override = false)
    {
        $loader = $this->getEagerLoader();
        if ($override === true) {
            $this->clearContain();
        }

        if ($associations === null) {
            return $loader->contain();
        }

        $queryBuilder = null;
        if (is_callable($override)) {
            $queryBuilder = $override;
        }

        $result = $loader->contain($associations, $queryBuilder);
        $this->_addAssociationsToTypeMap($this->repository(), $this->getTypeMap(), $result);

        return $this;
    }

    /**
     * Clears the contained associations from the current query.
     *
     * @return $this
     */
    public function clearContain()
    {
        $this->getEagerLoader()->clearContain();
        $this->_dirty();

        return $this;
    }

    /**
     * Used to recursively add contained association column types to
     * the query.
     *
     * @param \Cake\ORM\Table $table The table instance to pluck associations from.
     * @param \Cake\Database\TypeMap $typeMap The typemap to check for columns in.
     *   This typemap is indirectly mutated via Cake\ORM\Query::addDefaultTypes()
     * @param array $associations The nested tree of associations to walk.
     * @return void
     */
    protected function _addAssociationsToTypeMap($table, $typeMap, $associations)
    {
        foreach ($associations as $name => $nested) {
            if (!$table->hasAssociation($name)) {
                continue;
            }
            $association = $table->getAssociation($name);
            $target = $association->getTarget();
            $primary = (array)$target->getPrimaryKey();
            if (empty($primary) || $typeMap->type($target->aliasField($primary[0])) === null) {
                $this->addDefaultTypes($target);
            }
            if (!empty($nested)) {
                $this->_addAssociationsToTypeMap($target, $typeMap, $nested);
            }
        }
    }

    /**
     * Adds filtering conditions to this query to only bring rows that have a relation
     * to another from an associated table, based on conditions in the associated table.
     *
     * This function will add entries in the `contain` graph.
     *
     * ### Example:
     *
     * ```
     * // Bring only articles that were tagged with 'cake'
     * $query->matching('Tags', function ($q) {
     *     return $q->where(['name' => 'cake']);
     * );
     * ```
     *
     * It is possible to filter by deep associations by using dot notation:
     *
     * ### Example:
     *
     * ```
     * // Bring only articles that were commented by 'markstory'
     * $query->matching('Comments.Users', function ($q) {
     *     return $q->where(['username' => 'markstory']);
     * );
     * ```
     *
     * As this function will create `INNER JOIN`, you might want to consider
     * calling `distinct` on this query as you might get duplicate rows if
     * your conditions don't filter them already. This might be the case, for example,
     * of the same user commenting more than once in the same article.
     *
     * ### Example:
     *
     * ```
     * // Bring unique articles that were commented by 'markstory'
     * $query->distinct(['Articles.id'])
     * ->matching('Comments.Users', function ($q) {
     *     return $q->where(['username' => 'markstory']);
     * );
     * ```
     *
     * Please note that the query passed to the closure will only accept calling
     * `select`, `where`, `andWhere` and `orWhere` on it. If you wish to
     * add more complex clauses you can do it directly in the main query.
     *
     * @param string $assoc The association to filter by
     * @param callable|null $builder a function that will receive a pre-made query object
     * that can be used to add custom conditions or selecting some fields
     * @return $this
     */
    public function matching($assoc, callable $builder = null)
    {
        $result = $this->getEagerLoader()->setMatching($assoc, $builder)->getMatching();
        $this->_addAssociationsToTypeMap($this->repository(), $this->getTypeMap(), $result);
        $this->_dirty();

        return $this;
    }

    /**
     * Creates a LEFT JOIN with the passed association table while preserving
     * the foreign key matching and the custom conditions that were originally set
     * for it.
     *
     * This function will add entries in the `contain` graph.
     *
     * ### Example:
     *
     * ```
     * // Get the count of articles per user
     * $usersQuery
     *     ->select(['total_articles' => $query->func()->count('Articles.id')])
     *     ->leftJoinWith('Articles')
     *     ->group(['Users.id'])
     *     ->enableAutoFields(true);
     * ```
     *
     * You can also customize the conditions passed to the LEFT JOIN:
     *
     * ```
     * // Get the count of articles per user with at least 5 votes
     * $usersQuery
     *     ->select(['total_articles' => $query->func()->count('Articles.id')])
     *     ->leftJoinWith('Articles', function ($q) {
     *         return $q->where(['Articles.votes >=' => 5]);
     *     })
     *     ->group(['Users.id'])
     *     ->enableAutoFields(true);
     * ```
     *
     * This will create the following SQL:
     *
     * ```
     * SELECT COUNT(Articles.id) AS total_articles, Users.*
     * FROM users Users
     * LEFT JOIN articles Articles ON Articles.user_id = Users.id AND Articles.votes >= 5
     * GROUP BY USers.id
     * ```
     *
     * It is possible to left join deep associations by using dot notation
     *
     * ### Example:
     *
     * ```
     * // Total comments in articles by 'markstory'
     * $query
     *  ->select(['total_comments' => $query->func()->count('Comments.id')])
     *  ->leftJoinWith('Comments.Users', function ($q) {
     *     return $q->where(['username' => 'markstory']);
     * )
     * ->group(['Users.id']);
     * ```
     *
     * Please note that the query passed to the closure will only accept calling
     * `select`, `where`, `andWhere` and `orWhere` on it. If you wish to
     * add more complex clauses you can do it directly in the main query.
     *
     * @param string $assoc The association to join with
     * @param callable|null $builder a function that will receive a pre-made query object
     * that can be used to add custom conditions or selecting some fields
     * @return $this
     */
    public function leftJoinWith($assoc, callable $builder = null)
    {
        $result = $this->getEagerLoader()
            ->setMatching($assoc, $builder, [
                'joinType' => QueryInterface::JOIN_TYPE_LEFT,
                'fields' => false
            ])
            ->getMatching();
        $this->_addAssociationsToTypeMap($this->repository(), $this->getTypeMap(), $result);
        $this->_dirty();

        return $this;
    }

    /**
     * Creates an INNER JOIN with the passed association table while preserving
     * the foreign key matching and the custom conditions that were originally set
     * for it.
     *
     * This function will add entries in the `contain` graph.
     *
     * ### Example:
     *
     * ```
     * // Bring only articles that were tagged with 'cake'
     * $query->innerJoinWith('Tags', function ($q) {
     *     return $q->where(['name' => 'cake']);
     * );
     * ```
     *
     * This will create the following SQL:
     *
     * ```
     * SELECT Articles.*
     * FROM articles Articles
     * INNER JOIN tags Tags ON Tags.name = 'cake'
     * INNER JOIN articles_tags ArticlesTags ON ArticlesTags.tag_id = Tags.id
     *   AND ArticlesTags.articles_id = Articles.id
     * ```
     *
     * This function works the same as `matching()` with the difference that it
     * will select no fields from the association.
     *
     * @param string $assoc The association to join with
     * @param callable|null $builder a function that will receive a pre-made query object
     * that can be used to add custom conditions or selecting some fields
     * @return $this
     * @see \Cake\ORM\Query::matching()
     */
    public function innerJoinWith($assoc, callable $builder = null)
    {
        $result = $this->getEagerLoader()
            ->setMatching($assoc, $builder, [
                'joinType' => QueryInterface::JOIN_TYPE_INNER,
                'fields' => false
            ])
            ->getMatching();
        $this->_addAssociationsToTypeMap($this->repository(), $this->getTypeMap(), $result);
        $this->_dirty();

        return $this;
    }

    /**
     * Adds filtering conditions to this query to only bring rows that have no match
     * to another from an associated table, based on conditions in the associated table.
     *
     * This function will add entries in the `contain` graph.
     *
     * ### Example:
     *
     * ```
     * // Bring only articles that were not tagged with 'cake'
     * $query->notMatching('Tags', function ($q) {
     *     return $q->where(['name' => 'cake']);
     * );
     * ```
     *
     * It is possible to filter by deep associations by using dot notation:
     *
     * ### Example:
     *
     * ```
     * // Bring only articles that weren't commented by 'markstory'
     * $query->notMatching('Comments.Users', function ($q) {
     *     return $q->where(['username' => 'markstory']);
     * );
     * ```
     *
     * As this function will create a `LEFT JOIN`, you might want to consider
     * calling `distinct` on this query as you might get duplicate rows if
     * your conditions don't filter them already. This might be the case, for example,
     * of the same article having multiple comments.
     *
     * ### Example:
     *
     * ```
     * // Bring unique articles that were commented by 'markstory'
     * $query->distinct(['Articles.id'])
     * ->notMatching('Comments.Users', function ($q) {
     *     return $q->where(['username' => 'markstory']);
     * );
     * ```
     *
     * Please note that the query passed to the closure will only accept calling
     * `select`, `where`, `andWhere` and `orWhere` on it. If you wish to
     * add more complex clauses you can do it directly in the main query.
     *
     * @param string $assoc The association to filter by
     * @param callable|null $builder a function that will receive a pre-made query object
     * that can be used to add custom conditions or selecting some fields
     * @return $this
     */
    public function notMatching($assoc, callable $builder = null)
    {
        $result = $this->getEagerLoader()
            ->setMatching($assoc, $builder, [
                'joinType' => QueryInterface::JOIN_TYPE_LEFT,
                'fields' => false,
                'negateMatch' => true
            ])
            ->getMatching();
        $this->_addAssociationsToTypeMap($this->repository(), $this->getTypeMap(), $result);
        $this->_dirty();

        return $this;
    }

    /**
     * {@inheritDoc}
     *
     * Populates or adds parts to current query clauses using an array.
     * This is handy for passing all query clauses at once. The option array accepts:
     *
     * - fields: Maps to the select method
     * - conditions: Maps to the where method
     * - limit: Maps to the limit method
     * - order: Maps to the order method
     * - offset: Maps to the offset method
     * - group: Maps to the group method
     * - having: Maps to the having method
     * - contain: Maps to the contain options for eager loading
     * - join: Maps to the join method
     * - page: Maps to the page method
     *
     * ### Example:
     *
     * ```
     * $query->applyOptions([
     *   'fields' => ['id', 'name'],
     *   'conditions' => [
     *     'created >=' => '2013-01-01'
     *   ],
     *   'limit' => 10
     * ]);
     * ```
     *
     * Is equivalent to:
     *
     * ```
     * $query
     *   ->select(['id', 'name'])
     *   ->where(['created >=' => '2013-01-01'])
     *   ->limit(10)
     * ```
     */
    public function applyOptions(array $options)
    {
        $valid = [
            'fields' => 'select',
            'conditions' => 'where',
            'join' => 'join',
            'order' => 'order',
            'limit' => 'limit',
            'offset' => 'offset',
            'group' => 'group',
            'having' => 'having',
            'contain' => 'contain',
            'page' => 'page',
        ];

        ksort($options);
        foreach ($options as $option => $values) {
            if (isset($valid[$option], $values)) {
                $this->{$valid[$option]}($values);
            } else {
                $this->_options[$option] = $values;
            }
        }

        return $this;
    }

    /**
     * Creates a copy of this current query, triggers beforeFind and resets some state.
     *
     * The following state will be cleared:
     *
     * - autoFields
     * - limit
     * - offset
     * - map/reduce functions
     * - result formatters
     * - order
     * - containments
     *
     * This method creates query clones that are useful when working with subqueries.
     *
     * @return \Cake\ORM\Query
     */
    public function cleanCopy()
    {
        $clone = clone $this;
        $clone->setEagerLoader(clone $this->getEagerLoader());
        $clone->triggerBeforeFind();
        $clone->enableAutoFields(false);
        $clone->limit(null);
        $clone->order([], true);
        $clone->offset(null);
        $clone->mapReduce(null, null, true);
        $clone->formatResults(null, true);
        $clone->setSelectTypeMap(new TypeMap());
        $clone->decorateResults(null, true);

        return $clone;
    }

    /**
     * Object clone hook.
     *
     * Destroys the clones inner iterator and clones the value binder, and eagerloader instances.
     *
     * @return void
     */
    public function __clone()
    {
        parent::__clone();
        if ($this->_eagerLoader) {
            $this->_eagerLoader = clone $this->_eagerLoader;
        }
    }

    /**
     * {@inheritDoc}
     *
     * Returns the COUNT(*) for the query. If the query has not been
     * modified, and the count has already been performed the cached
     * value is returned
     */
    public function count()
    {
        if ($this->_resultsCount === null) {
            $this->_resultsCount = $this->_performCount();
        }

        return $this->_resultsCount;
    }

    /**
     * Performs and returns the COUNT(*) for the query.
     *
     * @return int
     */
    protected function _performCount()
    {
        $query = $this->cleanCopy();
        $counter = $this->_counter;
        if ($counter) {
            $query->counter(null);

            return (int)$counter($query);
        }

        $complex = (
            $query->clause('distinct') ||
            count($query->clause('group')) ||
            count($query->clause('union')) ||
            $query->clause('having')
        );

        if (!$complex) {
            // Expression fields could have bound parameters.
            foreach ($query->clause('select') as $field) {
                if ($field instanceof ExpressionInterface) {
                    $complex = true;
                    break;
                }
            }
        }

        if (!$complex && $this->_valueBinder !== null) {
            $order = $this->clause('order');
            $complex = $order === null ? false : $order->hasNestedExpression();
        }

        $count = ['count' => $query->func()->count('*')];

        if (!$complex) {
            $query->getEagerLoader()->enableAutoFields(false);
            $statement = $query
                ->select($count, true)
                ->enableAutoFields(false)
                ->execute();
        } else {
            $statement = $this->getConnection()->newQuery()
                ->select($count)
                ->from(['count_source' => $query])
                ->execute();
        }

        $result = $statement->fetch('assoc')['count'];
        $statement->closeCursor();

        return (int)$result;
    }

    /**
     * Registers a callable function that will be executed when the `count` method in
     * this query is called. The return value for the function will be set as the
     * return value of the `count` method.
     *
     * This is particularly useful when you need to optimize a query for returning the
     * count, for example removing unnecessary joins, removing group by or just return
     * an estimated number of rows.
     *
     * The callback will receive as first argument a clone of this query and not this
     * query itself.
     *
     * If the first param is a null value, the built-in counter function will be called
     * instead
     *
     * @param callable|null $counter The counter value
     * @return $this
     */
    public function counter($counter)
    {
        $this->_counter = $counter;

        return $this;
    }

    /**
     * Toggle hydrating entities.
     *
     * If set to false array results will be returned for the query.
     *
     * @param bool $enable Use a boolean to set the hydration mode.
     * @return $this
     */
    public function enableHydration($enable = true)
    {
        $this->_dirty();
        $this->_hydrate = (bool)$enable;

        return $this;
    }

    /**
     * Returns the current hydration mode.
     *
     * @return bool
     */
    public function isHydrationEnabled()
    {
        return $this->_hydrate;
    }

    /**
     * Toggle hydrating entities.
     *
     * If set to false array results will be returned.
     *
     * @deprecated 3.4.0 Use enableHydration()/isHydrationEnabled() instead.
     * @param bool|null $enable Use a boolean to set the hydration mode.
     *   Null will fetch the current hydration mode.
     * @return bool|$this A boolean when reading, and $this when setting the mode.
     */
    public function hydrate($enable = null)
    {
        deprecationWarning(
            'Query::hydrate() is deprecated. ' .
            'Use enableHydration()/isHydrationEnabled() instead.'
        );
        if ($enable === null) {
            return $this->isHydrationEnabled();
        }

        return $this->enableHydration($enable);
    }

    /**
     * {@inheritDoc}
     *
     * @return $this
     * @throws \RuntimeException When you attempt to cache a non-select query.
     */
    public function cache($key, $config = 'default')
    {
        if ($this->_type !== 'select' && $this->_type !== null) {
            throw new RuntimeException('You cannot cache the results of non-select queries.');
        }

        return $this->_cache($key, $config);
    }

    /**
     * {@inheritDoc}
     *
     * @throws \RuntimeException if this method is called on a non-select Query.
     */
    public function all()
    {
        if ($this->_type !== 'select' && $this->_type !== null) {
            throw new RuntimeException(
                'You cannot call all() on a non-select query. Use execute() instead.'
            );
        }

        return $this->_all();
    }

    /**
     * Trigger the beforeFind event on the query's repository object.
     *
     * Will not trigger more than once, and only for select queries.
     *
     * @return void
     */
    public function triggerBeforeFind()
    {
        if (!$this->_beforeFindFired && $this->_type === 'select') {
            $table = $this->repository();
            $this->_beforeFindFired = true;
            /* @var \Cake\Event\EventDispatcherInterface $table */
            $table->dispatchEvent('Model.beforeFind', [
                $this,
                new ArrayObject($this->_options),
                !$this->isEagerLoaded()
            ]);
        }
    }

    /**
     * {@inheritDoc}
     */
    public function sql(ValueBinder $binder = null)
    {
        $this->triggerBeforeFind();

        $this->_transformQuery();

        return parent::sql($binder);
    }

    /**
     * Executes this query and returns a ResultSet object containing the results.
     * This will also setup the correct statement class in order to eager load deep
     * associations.
     *
     * @return \Cake\ORM\ResultSet
     */
    protected function _execute()
    {
        $this->triggerBeforeFind();
        if ($this->_results) {
            $decorator = $this->_decoratorClass();

            return new $decorator($this->_results);
        }

        $statement = $this->getEagerLoader()->loadExternal($this, $this->execute());

        return new ResultSet($this, $statement);
    }

    /**
     * Applies some defaults to the query object before it is executed.
     *
     * Specifically add the FROM clause, adds default table fields if none are
     * specified and applies the joins required to eager load associations defined
     * using `contain`
     *
     * It also sets the default types for the columns in the select clause
     *
     * @see \Cake\Database\Query::execute()
     * @return void
     */
    protected function _transformQuery()
    {
        if (!$this->_dirty || $this->_type !== 'select') {
            return;
        }

        if (empty($this->_parts['from'])) {
            $this->from([$this->_repository->getAlias() => $this->_repository->getTable()]);
        }
        $this->_addDefaultFields();
        $this->getEagerLoader()->attachAssociations($this, $this->_repository, !$this->_hasFields);
        $this->_addDefaultSelectTypes();
    }

    /**
     * Inspects if there are any set fields for selecting, otherwise adds all
     * the fields for the default table.
     *
     * @return void
     */
    protected function _addDefaultFields()
    {
        $select = $this->clause('select');
        $this->_hasFields = true;

        if (!count($select) || $this->_autoFields === true) {
            $this->_hasFields = false;
            $this->select($this->repository()->getSchema()->columns());
            $select = $this->clause('select');
        }

        $aliased = $this->aliasFields($select, $this->repository()->getAlias());
        $this->select($aliased, true);
    }

    /**
     * Sets the default types for converting the fields in the select clause
     *
     * @return void
     */
    protected function _addDefaultSelectTypes()
    {
        $typeMap = $this->getTypeMap()->getDefaults();
        $select = $this->clause('select');
        $types = [];

        foreach ($select as $alias => $value) {
            if (isset($typeMap[$alias])) {
                $types[$alias] = $typeMap[$alias];
                continue;
            }
            if (is_string($value) && isset($typeMap[$value])) {
                $types[$alias] = $typeMap[$value];
            }
            if ($value instanceof TypedResultInterface) {
                $types[$alias] = $value->getReturnType();
            }
        }
        $this->getSelectTypeMap()->addDefaults($types);
    }

    /**
     * {@inheritDoc}
     *
     * @see \Cake\ORM\Table::find()
     */
    public function find($finder, array $options = [])
    {
        return $this->repository()->callFinder($finder, $this, $options);
    }

    /**
     * Marks a query as dirty, removing any preprocessed information
     * from in memory caching such as previous results
     *
     * @return void
     */
    protected function _dirty()
    {
        $this->_results = null;
        $this->_resultsCount = null;
        parent::_dirty();
    }

    /**
     * Create an update query.
     *
     * This changes the query type to be 'update'.
     * Can be combined with set() and where() methods to create update queries.
     *
     * @param string|null $table Unused parameter.
     * @return $this
     */
    public function update($table = null)
    {
        $table = $table ?: $this->repository()->getTable();

        return parent::update($table);
    }

    /**
     * Create a delete query.
     *
     * This changes the query type to be 'delete'.
     * Can be combined with the where() method to create delete queries.
     *
     * @param string|null $table Unused parameter.
     * @return $this
     */
    public function delete($table = null)
    {
        $repo = $this->repository();
        $this->from([$repo->getAlias() => $repo->getTable()]);

        return parent::delete();
    }

    /**
     * Create an insert query.
     *
     * This changes the query type to be 'insert'.
     * Note calling this method will reset any data previously set
     * with Query::values()
     *
     * Can be combined with the where() method to create delete queries.
     *
     * @param array $columns The columns to insert into.
     * @param array $types A map between columns & their datatypes.
     * @return $this
     */
    public function insert(array $columns, array $types = [])
    {
        $table = $this->repository()->getTable();
        $this->into($table);

        return parent::insert($columns, $types);
    }

    /**
     * {@inheritDoc}
     *
     * @throws \BadMethodCallException if the method is called for a non-select query
     */
    public function __call($method, $arguments)
    {
        if ($this->type() === 'select') {
            return $this->_call($method, $arguments);
        }

        throw new \BadMethodCallException(
            sprintf('Cannot call method "%s" on a "%s" query', $method, $this->type())
        );
    }

    /**
     * {@inheritDoc}
     */
    public function __debugInfo()
    {
        $eagerLoader = $this->getEagerLoader();

        return parent::__debugInfo() + [
            'hydrate' => $this->_hydrate,
            'buffered' => $this->_useBufferedResults,
            'formatters' => count($this->_formatters),
            'mapReducers' => count($this->_mapReduce),
            'contain' => $eagerLoader ? $eagerLoader->contain() : [],
            'matching' => $eagerLoader ? $eagerLoader->getMatching() : [],
            'extraOptions' => $this->_options,
            'repository' => $this->_repository
        ];
    }

    /**
     * Executes the query and converts the result set into JSON.
     *
     * Part of JsonSerializable interface.
     *
     * @return \Cake\Datasource\ResultSetInterface The data to convert to JSON.
     */
    public function jsonSerialize()
    {
        return $this->all();
    }

    /**
     * Sets whether or not the ORM should automatically append fields.
     *
     * By default calling select() will disable auto-fields. You can re-enable
     * auto-fields with this method.
     *
     * @param bool $value Set true to enable, false to disable.
     * @return $this
     */
    public function enableAutoFields($value = true)
    {
        $this->_autoFields = (bool)$value;

        return $this;
    }

    /**
     * Gets whether or not the ORM should automatically append fields.
     *
     * By default calling select() will disable auto-fields. You can re-enable
     * auto-fields with enableAutoFields().
     *
     * @return bool The current value.
     */
    public function isAutoFieldsEnabled()
    {
        return $this->_autoFields;
    }

    /**
     * Get/Set whether or not the ORM should automatically append fields.
     *
     * By default calling select() will disable auto-fields. You can re-enable
     * auto-fields with this method.
     *
     * @deprecated 3.4.0 Use enableAutoFields()/isAutoFieldsEnabled() instead.
     * @param bool|null $value The value to set or null to read the current value.
     * @return bool|$this Either the current value or the query object.
     */
    public function autoFields($value = null)
    {
        deprecationWarning(
            'Query::autoFields() is deprecated. ' .
            'Use enableAutoFields()/isAutoFieldsEnabled() instead.'
        );
        if ($value === null) {
            return $this->isAutoFieldsEnabled();
        }

        return $this->enableAutoFields($value);
    }

    /**
     * Decorates the results iterator with MapReduce routines and formatters
     *
     * @param \Traversable $result Original results
     * @return \Cake\Datasource\ResultSetInterface
     */
    protected function _decorateResults($result)
    {
        $result = $this->_applyDecorators($result);

        if (!($result instanceof ResultSet) && $this->isBufferedResultsEnabled()) {
            $class = $this->_decoratorClass();
            $result = new $class($result->buffered());
        }

        return $result;
    }
}