<?php

namespace MongoDB;

use MongoDB\Driver\Cursor;
use MongoDB\Driver\Manager;
use MongoDB\Driver\ReadConcern;
use MongoDB\Driver\ReadPreference;
use MongoDB\Driver\WriteConcern;
use MongoDB\Exception\InvalidArgumentException;
use MongoDB\Model\IndexInfoIterator;
use MongoDB\Operation\Aggregate;
use MongoDB\Operation\BulkWrite;
use MongoDB\Operation\CreateIndexes;
use MongoDB\Operation\Count;
use MongoDB\Operation\DeleteMany;
use MongoDB\Operation\DeleteOne;
use MongoDB\Operation\Distinct;
use MongoDB\Operation\DropCollection;
use MongoDB\Operation\DropIndexes;
use MongoDB\Operation\Find;
use MongoDB\Operation\FindOne;
use MongoDB\Operation\FindOneAndDelete;
use MongoDB\Operation\FindOneAndReplace;
use MongoDB\Operation\FindOneAndUpdate;
use MongoDB\Operation\InsertMany;
use MongoDB\Operation\InsertOne;
use MongoDB\Operation\ListIndexes;
use MongoDB\Operation\ReplaceOne;
use MongoDB\Operation\UpdateMany;
use MongoDB\Operation\UpdateOne;
use Traversable;

class Collection
{
    private static $defaultTypeMap = [
        'array' => 'MongoDB\Model\BSONArray',
        'document' => 'MongoDB\Model\BSONDocument',
        'root' => 'MongoDB\Model\BSONDocument',
    ];
    private static $wireVersionForFindAndModifyWriteConcern = 4;

    private $collectionName;
    private $databaseName;
    private $manager;
    private $readConcern;
    private $readPreference;
    private $typeMap;
    private $writeConcern;

    /**
     * Constructs new Collection instance.
     *
     * This class provides methods for collection-specific operations, such as
     * CRUD (i.e. create, read, update, and delete) and index management.
     *
     * Supported options:
     *
     *  * readConcern (MongoDB\Driver\ReadConcern): The default read concern to
     *    use for collection operations. Defaults to the Manager's read concern.
     *
     *  * readPreference (MongoDB\Driver\ReadPreference): The default read
     *    preference to use for collection operations. Defaults to the Manager's
     *    read preference.
     *
     *  * typeMap (array): Default type map for cursors and BSON documents.
     *
     *  * writeConcern (MongoDB\Driver\WriteConcern): The default write concern
     *    to use for collection operations. Defaults to the Manager's write
     *    concern.
     *
     * @param Manager $manager        Manager instance from the driver
     * @param string  $databaseName   Database name
     * @param string  $collectionName Collection name
     * @param array   $options        Collection options
     * @throws InvalidArgumentException
     */
    public function __construct(Manager $manager, $databaseName, $collectionName, array $options = [])
    {
        if (strlen($databaseName) < 1) {
            throw new InvalidArgumentException('$databaseName is invalid: ' . $databaseName);
        }

        if (strlen($collectionName) < 1) {
            throw new InvalidArgumentException('$collectionName is invalid: ' . $collectionName);
        }

        if (isset($options['readConcern']) && ! $options['readConcern'] instanceof ReadConcern) {
            throw InvalidArgumentException::invalidType('"readConcern" option', $options['readConcern'], 'MongoDB\Driver\ReadConcern');
        }

        if (isset($options['readPreference']) && ! $options['readPreference'] instanceof ReadPreference) {
            throw InvalidArgumentException::invalidType('"readPreference" option', $options['readPreference'], 'MongoDB\Driver\ReadPreference');
        }

        if (isset($options['typeMap']) && ! is_array($options['typeMap'])) {
            throw InvalidArgumentException::invalidType('"typeMap" option', $options['typeMap'], 'array');
        }

        if (isset($options['writeConcern']) && ! $options['writeConcern'] instanceof WriteConcern) {
            throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], 'MongoDB\Driver\WriteConcern');
        }

        $this->manager = $manager;
        $this->databaseName = (string) $databaseName;
        $this->collectionName = (string) $collectionName;
        $this->readConcern = isset($options['readConcern']) ? $options['readConcern'] : $this->manager->getReadConcern();
        $this->readPreference = isset($options['readPreference']) ? $options['readPreference'] : $this->manager->getReadPreference();
        $this->typeMap = isset($options['typeMap']) ? $options['typeMap'] : self::$defaultTypeMap;
        $this->writeConcern = isset($options['writeConcern']) ? $options['writeConcern'] : $this->manager->getWriteConcern();
    }

    /**
     * Return internal properties for debugging purposes.
     *
     * @see http://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
     * @return array
     */
    public function __debugInfo()
    {
        return [
            'collectionName' => $this->collectionName,
            'databaseName' => $this->databaseName,
            'manager' => $this->manager,
            'readConcern' => $this->readConcern,
            'readPreference' => $this->readPreference,
            'typeMap' => $this->typeMap,
            'writeConcern' => $this->writeConcern,
        ];
    }

    /**
     * Return the collection namespace (e.g. "db.collection").
     *
     * @see https://docs.mongodb.org/manual/faq/developers/#faq-dev-namespace
     * @return string
     */
    public function __toString()
    {
        return $this->databaseName . '.' . $this->collectionName;
    }

    /**
     * Executes an aggregation framework pipeline on the collection.
     *
     * Note: this method's return value depends on the MongoDB server version
     * and the "useCursor" option. If "useCursor" is true, a Cursor will be
     * returned; otherwise, an ArrayIterator is returned, which wraps the
     * "result" array from the command response document.
     *
     * Note: BSON deserialization of inline aggregation results (i.e. not using
     * a command cursor) does not yet support a custom type map
     * (depends on: https://jira.mongodb.org/browse/PHPC-314).
     *
     * @see Aggregate::__construct() for supported options
     * @param array $pipeline List of pipeline operations
     * @param array $options  Command options
     * @return Traversable
     */
    public function aggregate(array $pipeline, array $options = [])
    {
        $hasOutStage = \MongoDB\is_last_pipeline_operator_out($pipeline);

        /* A "majority" read concern is not compatible with the $out stage, so
         * avoid providing the Collection's read concern if it would conflict.
         */
        if ( ! isset($options['readConcern']) && ! ($hasOutStage && $this->readConcern->getLevel() === ReadConcern::MAJORITY)) {
            $options['readConcern'] = $this->readConcern;
        }

        if ( ! isset($options['readPreference'])) {
            $options['readPreference'] = $this->readPreference;
        }

        if ($hasOutStage) {
            $options['readPreference'] = new ReadPreference(ReadPreference::RP_PRIMARY);
        }

        if ( ! isset($options['typeMap']) && ( ! isset($options['useCursor']) || $options['useCursor'])) {
            $options['typeMap'] = $this->typeMap;
        }

        $operation = new Aggregate($this->databaseName, $this->collectionName, $pipeline, $options);
        $server = $this->manager->selectServer($options['readPreference']);

        return $operation->execute($server);
    }

    /**
     * Executes multiple write operations.
     *
     * @see BulkWrite::__construct() for supported options
     * @param array[] $operations List of write operations
     * @param array   $options    Command options
     * @return BulkWriteResult
     */
    public function bulkWrite(array $operations, array $options = [])
    {
        if ( ! isset($options['writeConcern'])) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new BulkWrite($this->databaseName, $this->collectionName, $operations, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Gets the number of documents matching the filter.
     *
     * @see Count::__construct() for supported options
     * @param array|object $filter  Query by which to filter documents
     * @param array        $options Command options
     * @return integer
     */
    public function count($filter = [], array $options = [])
    {
        if ( ! isset($options['readConcern'])) {
            $options['readConcern'] = $this->readConcern;
        }

        if ( ! isset($options['readPreference'])) {
            $options['readPreference'] = $this->readPreference;
        }

        $operation = new Count($this->databaseName, $this->collectionName, $filter, $options);
        $server = $this->manager->selectServer($options['readPreference']);

        return $operation->execute($server);
    }

    /**
     * Create a single index for the collection.
     *
     * @see Collection::createIndexes()
     * @param array|object $key     Document containing fields mapped to values,
     *                              which denote order or an index type
     * @param array        $options Index options
     * @return string The name of the created index
     */
    public function createIndex($key, array $options = [])
    {
        return current($this->createIndexes([['key' => $key] + $options]));
    }

    /**
     * Create one or more indexes for the collection.
     *
     * Each element in the $indexes array must have a "key" document, which
     * contains fields mapped to an order or type. Other options may follow.
     * For example:
     *
     *     $indexes = [
     *         // Create a unique index on the "username" field
     *         [ 'key' => [ 'username' => 1 ], 'unique' => true ],
     *         // Create a 2dsphere index on the "loc" field with a custom name
     *         [ 'key' => [ 'loc' => '2dsphere' ], 'name' => 'geo' ],
     *     ];
     *
     * If the "name" option is unspecified, a name will be generated from the
     * "key" document.
     *
     * @see http://docs.mongodb.org/manual/reference/command/createIndexes/
     * @see http://docs.mongodb.org/manual/reference/method/db.collection.createIndex/
     * @param array[] $indexes List of index specifications
     * @return string[] The names of the created indexes
     * @throws InvalidArgumentException if an index specification is invalid
     */
    public function createIndexes(array $indexes)
    {
        $operation = new CreateIndexes($this->databaseName, $this->collectionName, $indexes);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Deletes all documents matching the filter.
     *
     * @see DeleteMany::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/delete/
     * @param array|object $filter  Query by which to delete documents
     * @param array        $options Command options
     * @return DeleteResult
     */
    public function deleteMany($filter, array $options = [])
    {
        if ( ! isset($options['writeConcern'])) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new DeleteMany($this->databaseName, $this->collectionName, $filter, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Deletes at most one document matching the filter.
     *
     * @see DeleteOne::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/delete/
     * @param array|object $filter  Query by which to delete documents
     * @param array        $options Command options
     * @return DeleteResult
     */
    public function deleteOne($filter, array $options = [])
    {
        if ( ! isset($options['writeConcern'])) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new DeleteOne($this->databaseName, $this->collectionName, $filter, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Finds the distinct values for a specified field across the collection.
     *
     * @see Distinct::__construct() for supported options
     * @param string $fieldName Field for which to return distinct values
     * @param array|object $filter  Query by which to filter documents
     * @param array        $options Command options
     * @return mixed[]
     */
    public function distinct($fieldName, $filter = [], array $options = [])
    {
        if ( ! isset($options['readConcern'])) {
            $options['readConcern'] = $this->readConcern;
        }

        if ( ! isset($options['readPreference'])) {
            $options['readPreference'] = $this->readPreference;
        }

        $operation = new Distinct($this->databaseName, $this->collectionName, $fieldName, $filter, $options);
        $server = $this->manager->selectServer($options['readPreference']);

        return $operation->execute($server);
    }

    /**
     * Drop this collection.
     *
     * @see DropCollection::__construct() for supported options
     * @param array $options Additional options
     * @return array|object Command result document
     */
    public function drop(array $options = [])
    {
        if ( ! isset($options['typeMap'])) {
            $options['typeMap'] = $this->typeMap;
        }

        $operation = new DropCollection($this->databaseName, $this->collectionName, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Drop a single index in the collection.
     *
     * @see DropIndexes::__construct() for supported options
     * @param string $indexName Index name
     * @param array  $options   Additional options
     * @return array|object Command result document
     * @throws InvalidArgumentException if $indexName is an empty string or "*"
     */
    public function dropIndex($indexName, array $options = [])
    {
        $indexName = (string) $indexName;

        if ($indexName === '*') {
            throw new InvalidArgumentException('dropIndexes() must be used to drop multiple indexes');
        }

        if ( ! isset($options['typeMap'])) {
            $options['typeMap'] = $this->typeMap;
        }

        $operation = new DropIndexes($this->databaseName, $this->collectionName, $indexName, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Drop all indexes in the collection.
     *
     * @see DropIndexes::__construct() for supported options
     * @param array $options Additional options
     * @return array|object Command result document
     */
    public function dropIndexes(array $options = [])
    {
        if ( ! isset($options['typeMap'])) {
            $options['typeMap'] = $this->typeMap;
        }

        $operation = new DropIndexes($this->databaseName, $this->collectionName, '*', $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Finds documents matching the query.
     *
     * @see Find::__construct() for supported options
     * @see http://docs.mongodb.org/manual/core/read-operations-introduction/
     * @param array|object $filter  Query by which to filter documents
     * @param array        $options Additional options
     * @return Cursor
     */
    public function find($filter = [], array $options = [])
    {
        if ( ! isset($options['readConcern'])) {
            $options['readConcern'] = $this->readConcern;
        }

        if ( ! isset($options['readPreference'])) {
            $options['readPreference'] = $this->readPreference;
        }

        if ( ! isset($options['typeMap'])) {
            $options['typeMap'] = $this->typeMap;
        }

        $operation = new Find($this->databaseName, $this->collectionName, $filter, $options);
        $server = $this->manager->selectServer($options['readPreference']);

        return $operation->execute($server);
    }

    /**
     * Finds a single document matching the query.
     *
     * @see FindOne::__construct() for supported options
     * @see http://docs.mongodb.org/manual/core/read-operations-introduction/
     * @param array|object $filter  Query by which to filter documents
     * @param array        $options Additional options
     * @return array|object|null
     */
    public function findOne($filter = [], array $options = [])
    {
        if ( ! isset($options['readConcern'])) {
            $options['readConcern'] = $this->readConcern;
        }

        if ( ! isset($options['readPreference'])) {
            $options['readPreference'] = $this->readPreference;
        }

        if ( ! isset($options['typeMap'])) {
            $options['typeMap'] = $this->typeMap;
        }

        $operation = new FindOne($this->databaseName, $this->collectionName, $filter, $options);
        $server = $this->manager->selectServer($options['readPreference']);

        return $operation->execute($server);
    }

    /**
     * Finds a single document and deletes it, returning the original.
     *
     * The document to return may be null if no document matched the filter.
     *
     * Note: BSON deserialization of the returned document does not yet support
     * a custom type map (depends on: https://jira.mongodb.org/browse/PHPC-314).
     *
     * @see FindOneAndDelete::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
     * @param array|object $filter  Query by which to filter documents
     * @param array        $options Command options
     * @return object|null
     */
    public function findOneAndDelete($filter, array $options = [])
    {
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        if ( ! isset($options['writeConcern']) && \MongoDB\server_supports_feature($server, self::$wireVersionForFindAndModifyWriteConcern)) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new FindOneAndDelete($this->databaseName, $this->collectionName, $filter, $options);

        return $operation->execute($server);
    }

    /**
     * Finds a single document and replaces it, returning either the original or
     * the replaced document.
     *
     * The document to return may be null if no document matched the filter. By
     * default, the original document is returned. Specify
     * FindOneAndReplace::RETURN_DOCUMENT_AFTER for the "returnDocument" option
     * to return the updated document.
     *
     * Note: BSON deserialization of the returned document does not yet support
     * a custom type map (depends on: https://jira.mongodb.org/browse/PHPC-314).
     *
     * @see FindOneAndReplace::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
     * @param array|object $filter      Query by which to filter documents
     * @param array|object $replacement Replacement document
     * @param array        $options     Command options
     * @return object|null
     */
    public function findOneAndReplace($filter, $replacement, array $options = [])
    {
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        if ( ! isset($options['writeConcern']) && \MongoDB\server_supports_feature($server, self::$wireVersionForFindAndModifyWriteConcern)) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new FindOneAndReplace($this->databaseName, $this->collectionName, $filter, $replacement, $options);

        return $operation->execute($server);
    }

    /**
     * Finds a single document and updates it, returning either the original or
     * the updated document.
     *
     * The document to return may be null if no document matched the filter. By
     * default, the original document is returned. Specify
     * FindOneAndUpdate::RETURN_DOCUMENT_AFTER for the "returnDocument" option
     * to return the updated document.
     *
     * Note: BSON deserialization of the returned document does not yet support
     * a custom type map (depends on: https://jira.mongodb.org/browse/PHPC-314).
     *
     * @see FindOneAndReplace::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
     * @param array|object $filter  Query by which to filter documents
     * @param array|object $update  Update to apply to the matched document
     * @param array        $options Command options
     * @return object|null
     */
    public function findOneAndUpdate($filter, $update, array $options = [])
    {
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        if ( ! isset($options['writeConcern']) && \MongoDB\server_supports_feature($server, self::$wireVersionForFindAndModifyWriteConcern)) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new FindOneAndUpdate($this->databaseName, $this->collectionName, $filter, $update, $options);

        return $operation->execute($server);
    }

    /**
     * Return the collection name.
     *
     * @return string
     */
    public function getCollectionName()
    {
        return $this->collectionName;
    }

    /**
     * Return the database name.
     *
     * @return string
     */
    public function getDatabaseName()
    {
        return $this->databaseName;
    }

    /**
     * Return the Manager.
     *
     * @return Manager
     */
    public function getManager()
    {
        return $this->manager;
    }

    /**
     * Return the collection namespace.
     *
     * @see https://docs.mongodb.org/manual/reference/glossary/#term-namespace
     * @return string
     */
    public function getNamespace()
    {
        return $this->databaseName . '.' . $this->collectionName;
    }

    /**
     * Inserts multiple documents.
     *
     * @see InsertMany::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/insert/
     * @param array[]|object[] $documents The documents to insert
     * @param array            $options   Command options
     * @return InsertManyResult
     */
    public function insertMany(array $documents, array $options = [])
    {
        if ( ! isset($options['writeConcern'])) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new InsertMany($this->databaseName, $this->collectionName, $documents, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Inserts one document.
     *
     * @see InsertOne::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/insert/
     * @param array|object $document The document to insert
     * @param array        $options  Command options
     * @return InsertOneResult
     */
    public function insertOne($document, array $options = [])
    {
        if ( ! isset($options['writeConcern'])) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new InsertOne($this->databaseName, $this->collectionName, $document, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Returns information for all indexes for the collection.
     *
     * @see ListIndexes::__construct() for supported options
     * @return IndexInfoIterator
     */
    public function listIndexes(array $options = [])
    {
        $operation = new ListIndexes($this->databaseName, $this->collectionName, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Replaces at most one document matching the filter.
     *
     * @see ReplaceOne::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/update/
     * @param array|object $filter      Query by which to filter documents
     * @param array|object $replacement Replacement document
     * @param array        $options     Command options
     * @return UpdateResult
     */
    public function replaceOne($filter, $replacement, array $options = [])
    {
        if ( ! isset($options['writeConcern'])) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new ReplaceOne($this->databaseName, $this->collectionName, $filter, $replacement, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Updates all documents matching the filter.
     *
     * @see UpdateMany::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/update/
     * @param array|object $filter  Query by which to filter documents
     * @param array|object $update  Update to apply to the matched documents
     * @param array        $options Command options
     * @return UpdateResult
     */
    public function updateMany($filter, $update, array $options = [])
    {
        if ( ! isset($options['writeConcern'])) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new UpdateMany($this->databaseName, $this->collectionName, $filter, $update, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Updates at most one document matching the filter.
     *
     * @see UpdateOne::__construct() for supported options
     * @see http://docs.mongodb.org/manual/reference/command/update/
     * @param array|object $filter  Query by which to filter documents
     * @param array|object $update  Update to apply to the matched document
     * @param array        $options Command options
     * @return UpdateResult
     */
    public function updateOne($filter, $update, array $options = [])
    {
        if ( ! isset($options['writeConcern'])) {
            $options['writeConcern'] = $this->writeConcern;
        }

        $operation = new UpdateOne($this->databaseName, $this->collectionName, $filter, $update, $options);
        $server = $this->manager->selectServer(new ReadPreference(ReadPreference::RP_PRIMARY));

        return $operation->execute($server);
    }

    /**
     * Get a clone of this collection with different options.
     *
     * @see Collection::__construct() for supported options
     * @param array $options Collection constructor options
     * @return Collection
     */
    public function withOptions(array $options = [])
    {
        $options += [
            'readConcern' => $this->readConcern,
            'readPreference' => $this->readPreference,
            'typeMap' => $this->typeMap,
            'writeConcern' => $this->writeConcern,
        ];

        return new Collection($this->manager, $this->databaseName, $this->collectionName, $options);
    }
}
