<?php
/**
 * @package Google Cloud Platform 
 *
 * @author Velz
 *
 *   
 * Description : To upload images and files.
 */
 
if (!defined('BASEPATH'))
    exit('No direct script access allowed');

include_once APPPATH.'/vendor/autoload.php';
use Google\Cloud\Storage\StorageClient;


class Googlecloud
{
    private $googleClient;
    private $CI;
	

	public function __construct()
    {
		// 'keyFilePath' => APPPATH.'/client_secret_storage_389134811365-cnd4r6014l500bfpskt7ahs2apvcu3mm.apps.googleusercontent.com.json'
		$this->CI =& get_instance();
		$this->googleClient = new StorageClient([
			'keyFilePath' => $_SERVER['DOCUMENT_ROOT'].'/env/cet_gcp_credential.json'		
		]);
		
		// Authenticate using keyfile data
		// $this->googleClient = new StorageClient([
		// 	'keyFile' => json_decode(file_get_contents(APPPATH.'/client_secret_storage_389134811365-cnd4r6014l500bfpskt7ahs2apvcu3mm.apps.googleusercontent.com.json'), true)
		// ]);
    }

	/**
	 * List all Cloud Storage buckets for the current project.
	 * Refer : get_bucket_metadata() in GCP Docs
	 */
	public function listAllBuckets() 
	{
		//    $storage = new StorageClient();
	          $storage = $this->googleClient;
			  $array = array();
	          try{$buckets = $storage->buckets();
				foreach ($storage->buckets() as $bucket) {
					// printf('Bucket: %s' . PHP_EOL, $bucket->name());
					array_push($array, $bucket->name());
				}
				return $array;
			  } 
			  catch (Exception $ex) {
				return $ex->getMessage() . "\n<pre>";
				       print_r($ex->getTraceAsString());
				       "</pre>";
			   }
	}
	

	/**
	 * Create a new bucket with a custom default storage class and location.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * Refer : create_bucket_class_location() in GCP Docs
	 */
	function createNewBucket(string $bucketName): string
	{
			// $storage = new StorageClient();
			try {
				$storage = $this->googleClient;
				$storageClass = 'COLDLINE';
				$location = 'ASIA';
				$bucket = $storage->createBucket($bucketName, [
					'storageClass' => $storageClass,
					'location' => $location,
				]);

				$objects = $bucket->objects([
					'encryption' => [ 'defaultKmsKeyName' => null,]
				]);
				return $bucketName;
				// printf('Created bucket %s in %s with storage class %s', $bucketName, $storageClass, $location);
		    } catch (Exception $ex) {
				return $ex->getMessage() . "\n<pre>";
				       print_r($ex->getTraceAsString());
				       "</pre>";
				
			}
	}

	/**
	 * Upload a file.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * @param string $objectName The name of your Cloud Storage object.
	 *        (e.g. 'my-object')
	 * @param string $source The path to the file to upload.
	 *        (e.g. '/path/to/your/file')
	 * Refer : upload_object() in GCP Docs
	 */
	function uploadFileToGCPBucket(string $bucketName, string $objectName, string $source)
	{ 
		// $storage = new StorageClient();
		$result = '';
		try {
			$storage = $this->googleClient;
			$file = fopen($source, 'r');
			$bucket = $storage->bucket($bucketName);
			$object = $bucket->upload($file, [
				'name' => $objectName
			]);
			// $result = $object;
			// print_r($result);
			$result =  true;
		} 
		catch (Exception $ex) {
			$result =  false;
		 }
		 return $result;
			// printf('Uploaded %s to gs://%s/%s' . PHP_EOL, basename($source), $bucketName, $objectName);
	}

	/**
	 * Generate a v4 signed URL for downloading an object.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * @param string $objectName The name of your Cloud Storage object.
	 *        (e.g. 'my-object')
	 * Refer : get_object_v4_signed_url() in GCP Docs
	 */
	function getSingleObjectInaBucketAsSignedURI(string $bucketName, string $objectName): string
	{
		
		try {
			$storage = $this->googleClient;
			$bucket = $storage->bucket($bucketName);
			$object = $bucket->object($objectName);
			$url = $object->signedUrl(
				# This URL is valid for 15 minutes
				new \DateTime('15 min'),
				[
					'version' => 'v4',
				]
			);
			$presignedUrl = (string) $url;		

			// print('Generated GET signed URL:' . PHP_EOL);
			// print($url . PHP_EOL);
			// print('You can use this URL with any user agent, for example:' . PHP_EOL);
			// print('curl ' . $url . PHP_EOL);
		}catch (Exception $ex) {
			return $ex->getMessage() . "\n<pre>";
				   print_r($ex->getTraceAsString());
				   "</pre>";
		   }
		
			return $presignedUrl;
	}

	/**
	 * List Cloud Storage bucket objects.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * Refer : list_objects() in GCP Docs
	 */
	function getAllObjectsInaBucket(string $bucketName)
	{
		// $storage = new StorageClient();
		$objects = array();
		try {
					$storage = $this->googleClient;
					$bucket = $storage->bucket($bucketName);
					
					foreach ($bucket->objects() as $object) {
						// printf('Object: %s' . PHP_EOL, $object->name());
						array_push($objects, $object->name());
					}
		} catch (Exception $ex) {
			return $ex->getMessage() . "\n<pre>";
				   print_r($ex->getTraceAsString());
				   "</pre>";
		   }
				
		return $objects;
	}
	/**
	 * Delete an object.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * @param string $objectName The name of your Cloud Storage object.
	 *        (e.g. 'my-object')
	 * Refer : delete_object() in GCP Docs
	 */
	function deleteSingleObjFromBucket(string $bucketName, string $objectName): string
	{
		// $storage = new StorageClient();
		$storage = $this->googleClient;
		$bucket = $storage->bucket($bucketName);
		$object = $bucket->object($objectName);
		$object->delete();
		// printf('Deleted gs://%s/%s' . PHP_EOL, $bucketName, $objectName);
		return 'Deleted gs://%s/%s' . PHP_EOL.$objectName;
	}

	/**
	 * Change the default storage class for the given bucket.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 */
	function change_default_storage_class(string $bucketName): void
	{
		$storage = new StorageClient();
		$bucket = $storage->bucket($bucketName);

		$storageClass = 'COLDLINE';

		$bucket->update([
			'storageClass' => $storageClass,
		]);

		printf(
			'Default storage class for bucket %s has been set to %s',
			$bucketName,
			$storageClass
		);
	}

	/**
	 * Delete a Cloud Storage Bucket.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * Refer : delete_bucket() in GCP Docs.
	 */
	function delete_bucket(string $bucketName): void
	{
		// $storage = new StorageClient();
		$storage = $this->googleClient;
		$bucket = $storage->bucket($bucketName);
		$bucket->delete();
		printf('Bucket deleted: %s' . PHP_EOL, $bucket->name());
	}

	/**
	 * Get bucket metadata.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * Refer : get_bucket_metadata() in GCP Docs
	 */
	function get_bucket_metadata(string $bucketName): void
	{
		// $storage = new StorageClient();
		$storage = $this->googleClient;
		$bucket = $storage->bucket($bucketName);
		$info = $bucket->info();

		printf('Bucket Metadata: %s' . PHP_EOL, print_r($info));
	}

	/**
	 * Download an object from Cloud Storage and save it as a local file.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * @param string $objectName The name of your Cloud Storage object.
	 *        (e.g. 'my-object')
	 * @param string $destination The local destination to save the object.
	 *        (e.g. '/path/to/your/file')
	 * Refer : download_object() in GCP Docs
	 */
	function download_object(string $bucketName, string $objectName, string $destination): void
	{
		
			$storage = $this->googleClient;
			$bucket = $storage->bucket($bucketName);
			$object = $bucket->object($objectName);
			$object->downloadToFile($destination);
			printf(
				'Downloaded gs://%s/%s to %s' . PHP_EOL,
				$bucketName,
				$objectName,
				basename($destination));
	}


	/**
	 * Copy an object to a new name and/or bucket.
	 *
	 * @param string $bucketName The name of your Cloud Storage bucket.
	 *        (e.g. 'my-bucket')
	 * @param string $objectName The name of your Cloud Storage object.
	 *        (e.g. 'my-object')
	 * @param string $newBucketName The destination bucket name.
	 *        (e.g. 'my-other-bucket')
	 * @param string $newObjectName The destination object name.
	 *        (e.g. 'my-other-object')
	 * Refer : copy_object() in GCP Docs
	 */
	function copyGCPObject(string $bucketName, string $objectName, string $newBucketName, string $newObjectName): void
	{
		$storage = new StorageClient();
		$bucket = $storage->bucket($bucketName);
		$object = $bucket->object($objectName);
		$object->copy($newBucketName, ['name' => $newObjectName]);
		printf('Copied gs://%s/%s to gs://%s/%s' . PHP_EOL,
			$bucketName, $objectName, $newBucketName, $newObjectName);
	}
	
}

?>