From 25c25ceadd490384a03214311111f50d399dbf3e Mon Sep 17 00:00:00 2001
From: Thomas <thomas@lekoala.be>
Date: Mon, 5 Feb 2024 17:04:48 +0100
Subject: [PATCH] make phpstan happy

---
 .travis.yml                    |  68 ------------
 src/EmailUtils.php             |   7 +-
 src/SparkPostAdmin.php         | 169 +++++++++++++++++++++--------
 src/SparkPostApiTransport.php  |  59 ++++++----
 src/SparkPostController.php    |  44 ++++++--
 src/SparkPostHelper.php        |  47 ++++++--
 src/api/SparkPostApiClient.php | 192 +++++++++++++++++++--------------
 7 files changed, 352 insertions(+), 234 deletions(-)
 delete mode 100644 .travis.yml

diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index f16d7f1..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,68 +0,0 @@
-language: php
-
-os: linux
-
-dist: xenial
-
-services:
-  - mysql
-  - postgresql
-
-cache:
-  directories:
-    - $HOME/.composer/cache/files
-
-env:
-  global:
-    - SS_ENVIRONMENT_TYPE=dev
-    - SS_BASE_URL="http://localhost:8080/"
-
-jobs:
-  fast_finish: true
-  include:
-    - php: 7.4
-      env:
-        - DB=PGSQL
-        - PDO=1
-        - PHPCS_TEST=1
-        - PHPUNIT_TEST=1
-        - PHPUNIT_COVERAGE_TEST=1
-    - php: 8.0
-      env:
-        - DB=MYSQL
-        - PDO=1
-    - php: 8.1
-      env:
-        - DB=MYSQL
-        - PDO=1
-
-before_script:
-  # COMPOSER
-  # install $COMPOSER_VERSION if defined, otherwise use Composer v1 with PHP <= 7.3, Composer v2 for >= 7.3
-  - if [ $COMPOSER_VERSION ] ; then composer self-update --$COMPOSER_VERSION ; elif [ $(php -r 'echo (int) version_compare(phpversion(), "7.3.0", "<=");') = "1" ] ; then composer self-update --1; else composer self-update --2; fi
-  - composer --version
-
-  # PHPENV
-  - phpenv rehash
-  - phpenv config-rm xdebug.ini || true
-  - if [[ $PHPUNIT_COVERAGE_TEST ]]; then memlimit='8192M'; else memlimit='4096M'; fi
-  - echo "memory_limit = ${memlimit}" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
-  - echo 'always_populate_raw_post_data = -1' >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
-
-  # Install composer dependencies
-  - composer validate
-  - if [[ $DB == PGSQL ]]; then composer require silverstripe/postgresql:^2 --no-update; fi
-  - if [[ $DB == SQLITE ]]; then composer require silverstripe/sqlite3:^2 --no-update; fi
-  - if [[ $PHPCS_TEST ]]; then composer global require squizlabs/php_codesniffer:^3 --prefer-dist --no-interaction --no-progress --no-suggest -o; fi
-  - composer install --prefer-source --no-interaction --no-progress --no-suggest --optimize-autoloader --verbose --profile
-
-  # Log constants to CI for debugging purposes
-  - php vendor/silverstripe/framework/tests/dump_constants.php
-
-script:
-  - if [[ $PHPUNIT_TEST ]]; then vendor/bin/phpunit; fi
-  - if [[ $PHPCS_TEST ]]; then composer run-script lint; fi
-  - if [[ $PHPUNIT_COVERAGE_TEST ]]; then phpdbg -qrr vendor/bin/phpunit --coverage-clover=coverage.xml; fi
-
-after_success:
-  - if [[ $PHPUNIT_COVERAGE_TEST ]]; then bash <(curl -s https://codecov.io/bash) -f coverage.xml; fi
diff --git a/src/EmailUtils.php b/src/EmailUtils.php
index 3ce26d8..bbb4706 100644
--- a/src/EmailUtils.php
+++ b/src/EmailUtils.php
@@ -9,7 +9,7 @@
 class EmailUtils
 {
     /**
-     * Inline styles using Pelago Emogrifier V6
+     * Inline styles using Pelago Emogrifier V7
      *
      * This is much better than the functionnality provided by SparkPost anyway
      *
@@ -90,10 +90,9 @@ public static function get_email_from_rfc_email($rfc_email_string)
     }
 
     /**
-     * Useful when dealing with legacy code
-     *
+     * @deprecated
      * @param \SilverStripe\Control\Email\Email $Email
-     * @return \Symfony\Component\Mime\Header\Headers|Swift_Mime_SimpleHeaderSet
+     * @return \Symfony\Component\Mime\Header\Headers
      */
     public static function getHeaders($Email)
     {
diff --git a/src/SparkPostAdmin.php b/src/SparkPostAdmin.php
index 319656a..40156b2 100644
--- a/src/SparkPostAdmin.php
+++ b/src/SparkPostAdmin.php
@@ -8,6 +8,7 @@
 use SilverStripe\Forms\TabSet;
 use SilverStripe\ORM\ArrayLib;
 use SilverStripe\ORM\ArrayList;
+use SilverStripe\ORM\DataObject;
 use SilverStripe\View\ArrayData;
 use SilverStripe\Control\Session;
 use SilverStripe\Forms\DateField;
@@ -23,9 +24,11 @@
 use SilverStripe\View\ViewableData;
 use SilverStripe\Forms\LiteralField;
 use SilverStripe\Control\Email\Email;
+use SilverStripe\Control\HTTPRequest;
 use SilverStripe\Forms\DropdownField;
 use SilverStripe\Security\Permission;
 use LeKoala\SparkPost\SparkPostHelper;
+use SilverStripe\Control\HTTPResponse;
 use SilverStripe\Forms\CompositeField;
 use SilverStripe\SiteConfig\SiteConfig;
 use SilverStripe\Forms\GridField\GridField;
@@ -46,15 +49,33 @@
  */
 class SparkPostAdmin extends LeftAndMain implements PermissionProvider
 {
-
     const MESSAGE_CACHE_MINUTES = 5;
     const WEBHOOK_CACHE_MINUTES = 1440; // 1 day
     const SENDINGDOMAIN_CACHE_MINUTES = 1440; // 1 day
 
+    /**
+     * @var string
+     */
     private static $menu_title = "SparkPost";
+
+    /**
+     * @var string
+     */
     private static $url_segment = "sparkpost";
+
+    /**
+     * @var string
+     */
     private static $menu_icon = "sparkpost/images/sparkpost-icon.png";
+
+    /**
+     * @var string
+     */
     private static $url_rule = '/$Action/$ID/$OtherID';
+
+    /**
+     * @var array<string>
+     */
     private static $allowed_actions = [
         'settings',
         'SearchForm',
@@ -66,6 +87,9 @@ class SparkPostAdmin extends LeftAndMain implements PermissionProvider
         "send_test",
     ];
 
+    /**
+     * @var boolean
+     */
     private static $cache_enabled = true;
 
     /**
@@ -74,19 +98,19 @@ class SparkPostAdmin extends LeftAndMain implements PermissionProvider
     protected $subaccountKey = false;
 
     /**
-     * @var Exception
+     * @var Exception|null
      */
-    protected $lastException;
+    protected $lastException = null;
 
     /**
-     * @var ViewableData
+     * @var ViewableData|null
      */
-    protected $currentMessage;
+    protected $currentMessage = null;
 
     /**
      * Inject public dependencies into the controller
      *
-     * @var array
+     * @var array<string,string>
      */
     private static $dependencies = [
         'logger' => '%$Psr\Log\LoggerInterface',
@@ -94,15 +118,18 @@ class SparkPostAdmin extends LeftAndMain implements PermissionProvider
     ];
 
     /**
-     * @var Psr\Log\LoggerInterface
+     * @var \Psr\Log\LoggerInterface
      */
     public $logger;
 
     /**
-     * @var Psr\SimpleCache\CacheInterface
+     * @var \Psr\SimpleCache\CacheInterface
      */
     public $cache;
 
+    /**
+     * @return void
+     */
     public function init()
     {
         parent::init();
@@ -112,11 +139,19 @@ public function init()
         }
     }
 
+    /**
+     * @param HTTPRequest $request
+     * @return HTTPResponse
+     */
     public function settings($request)
     {
         return parent::index($request);
     }
 
+    /**
+     * @param HTTPRequest $request
+     * @return HTTPResponse|null
+     */
     public function send_test($request)
     {
         if (!$this->CanConfigureApi()) {
@@ -132,8 +167,9 @@ public function send_test($request)
         $email->setBody("Test " . date('Y-m-d H:i:s'));
         $email->setTo($to);
 
-        $result = $email->send();
-        var_dump($result);
+        $email->send();
+        var_dump('Email sent!');
+        return null;
     }
 
     /**
@@ -146,7 +182,9 @@ public function getSession()
 
     /**
      * Returns a GridField of messages
-     * @return CMSForm
+     * @param mixed $id
+     * @param mixed $fields
+     * @return null|Form
      */
     public function getEditForm($id = null, $fields = null)
     {
@@ -156,6 +194,7 @@ public function getEditForm($id = null, $fields = null)
 
         $form = parent::getEditForm($id);
 
+        /** @var DataObject|null $record */
         $record = $this->getRecord($id);
 
         // Check if this record is viewable
@@ -208,7 +247,7 @@ public function getEditForm($id = null, $fields = null)
             }
 
             if ($validator) {
-                /** @var GridFieldDetailForm $detailForm  */
+                /** @var GridFieldDetailForm|null $detailForm  */
                 $detailForm = $messageListConfig->getComponentByType(GridFieldDetailForm::class);
                 if ($detailForm) {
                     $detailForm->setValidator($validator);
@@ -223,16 +262,15 @@ public function getEditForm($id = null, $fields = null)
             $this->SearchFields(),
             $messagesList,
             // necessary for tree node selection in LeftAndMain.EditForm.js
-            new HiddenField('ID', false, 0)
+            new HiddenField('ID', null, 0)
         );
 
         $fields = new FieldList([
             $root = new TabSet('Root', $messagesTab)
         ]);
 
+        $settingsTab = new Tab('Settings', _t('SparkPostAdmin.Settings', 'Settings'));
         if ($this->CanConfigureApi()) {
-            $settingsTab = new Tab('Settings', _t('SparkPostAdmin.Settings', 'Settings'));
-
             $domainTabData = $this->DomainTab();
             $settingsTab->push($domainTabData);
 
@@ -312,7 +350,7 @@ public function getEditForm($id = null, $fields = null)
     /**
      * Get logger
      *
-     * @return  Psr\Log\LoggerInterface
+     * @return \Psr\Log\LoggerInterface
      */
     public function getLogger()
     {
@@ -322,7 +360,7 @@ public function getLogger()
     /**
      * Get the cache
      *
-     * @return Psr\SimpleCache\CacheInterface
+     * @return \Psr\SimpleCache\CacheInterface
      */
     public function getCache()
     {
@@ -351,9 +389,9 @@ public function getCacheEnabled()
      * A simple cache helper
      *
      * @param string $method
-     * @param array $params
+     * @param array<mixed>|null|string|bool $params
      * @param int $expireInSeconds
-     * @return array
+     * @return array<mixed>|false
      */
     protected function getCachedData($method, $params, $expireInSeconds = 60)
     {
@@ -384,6 +422,9 @@ protected function getCachedData($method, $params, $expireInSeconds = 60)
         return $data;
     }
 
+    /**
+     * @return array<mixed>
+     */
     public function getParams()
     {
         $params = $this->config()->default_search_params;
@@ -399,9 +440,11 @@ public function getParams()
 
         // Respect api formats
         if (!empty($params['to'])) {
+            //@phpstan-ignore-next-line
             $params['to'] = date('Y-m-d', strtotime(str_replace('/', '-', $params['to']))) . 'T00:00';
         }
         if (!empty($params['from'])) {
+            //@phpstan-ignore-next-line
             $params['from'] = date('Y-m-d', strtotime(str_replace('/', '-', $params['from']))) . 'T23:59';
         }
 
@@ -410,6 +453,11 @@ public function getParams()
         return $params;
     }
 
+    /**
+     * @param string $name
+     * @param mixed $default
+     * @return mixed
+     */
     public function getParam($name, $default = null)
     {
         $data = $this->getSession()->get(__class__ . '.Search');
@@ -419,6 +467,9 @@ public function getParam($name, $default = null)
         return (isset($data[$name]) && strlen($data[$name])) ? $data[$name] : $default;
     }
 
+    /**
+     * @return CompositeField
+     */
     public function SearchFields()
     {
         $disabled_filters = $this->config()->disabled_search_filters;
@@ -467,6 +518,9 @@ public function SearchFields()
         return $fields;
     }
 
+    /**
+     * @return Form
+     */
     public function SearchForm()
     {
         $SearchForm = new Form($this, 'SearchForm', new FieldList(), new FieldList([
@@ -476,6 +530,11 @@ public function SearchForm()
         return $SearchForm;
     }
 
+    /**
+     * @param array<mixed> $data
+     * @param Form $form
+     * @return HTTPResponse
+     */
     public function doSearch($data, Form $form)
     {
         $post = $this->getRequest()->postVar('params');
@@ -554,7 +613,7 @@ public function Messages()
     /**
      * Provides custom permissions to the Security section
      *
-     * @return array
+     * @return array<string,mixed>
      */
     public function providePermissions()
     {
@@ -619,7 +678,7 @@ protected function FormGroupHelper($html)
      */
     public function IsAdmin()
     {
-        return Permission::check("ADMIN");
+        return boolval(Permission::check("ADMIN"));
     }
 
     /**
@@ -635,11 +694,10 @@ public function canView($member = null)
         if (!($transport instanceof SparkPostApiTransport)) {
             return false;
         }
-        return Permission::check("CMS_ACCESS_SparkPost", 'any', $member);
+        return boolval(Permission::check("CMS_ACCESS_SparkPost", 'any', $member));
     }
 
     /**
-     *
      * @return bool
      */
     public function CanConfigureApi()
@@ -650,7 +708,7 @@ public function CanConfigureApi()
     /**
      * Check if webhook is installed
      *
-     * @return array|false
+     * @return array<mixed>|false
      */
     public function WebhookInstalled()
     {
@@ -689,7 +747,7 @@ public function WebhookInstalled()
 
     /**
      * Hook details for template
-     * @return \ArrayData
+     * @return ArrayData|null
      */
     public function WebhookDetails()
     {
@@ -697,6 +755,7 @@ public function WebhookDetails()
         if ($el) {
             return new ArrayData($el);
         }
+        return null;
     }
 
     /**
@@ -710,7 +769,7 @@ public function WebhookTab()
         if ($webhook) {
             return $this->UninstallHookForm($webhook);
         }
-        return $this->InstallHookForm($webhook);
+        return $this->InstallHookForm();
     }
 
     /**
@@ -722,7 +781,10 @@ public function WebhookUrl()
             return rtrim(self::config()->webhook_base_url, '/') . '/sparkpost/incoming';
         }
         if (Director::isLive()) {
-            return Director::absoluteURL('/sparkpost/incoming');
+            $absurl = Director::absoluteURL('/sparkpost/incoming');
+            if ($absurl && is_string($absurl)) {
+                return $absurl;
+            }
         }
         $protocol = Director::protocol();
         return $protocol . $this->getDomain() . '/sparkpost/incoming';
@@ -731,10 +793,9 @@ public function WebhookUrl()
     /**
      * Install hook form
      *
-     * @param array $data
      * @return FormField
      */
-    public function InstallHookForm($data)
+    public function InstallHookForm()
     {
         $fields = new CompositeField();
         $fields->push(new LiteralField('Info', $this->MessageHelper(
@@ -748,6 +809,9 @@ public function InstallHookForm($data)
         return $fields;
     }
 
+    /**
+     * @return HTTPResponse
+     */
     public function doInstallHook()
     {
         if (!$this->CanConfigureApi()) {
@@ -784,7 +848,7 @@ public function doInstallHook()
     /**
      * Uninstall hook form
      *
-     * @param array $data
+     * @param array<mixed> $data
      * @return FormField
      */
     public function UninstallHookForm($data)
@@ -824,6 +888,11 @@ public function UninstallHookForm($data)
         return $fields;
     }
 
+    /**
+     * @param array<mixed> $data
+     * @param Form $form
+     * @return HTTPResponse
+     */
     public function doUninstallHook($data, Form $form)
     {
         if (!$this->CanConfigureApi()) {
@@ -848,7 +917,7 @@ public function doUninstallHook($data, Form $form)
     /**
      * Check if sending domain is installed
      *
-     * @return array
+     * @return array<mixed>|false
      */
     public function SendingDomainInstalled()
     {
@@ -863,16 +932,18 @@ public function SendingDomainInstalled()
     /**
      * Trigger request to check if sending domain is verified
      *
-     * @return array
+     * @return array<mixed>|false
      */
     public function VerifySendingDomain()
     {
         $client = SparkPostHelper::getClient();
 
         $host = $this->getDomain();
+        if (!$host && is_bool($host)) {
+            return false;
+        }
 
         $verification = $client->verifySendingDomain($host);
-
         if (empty($verification)) {
             return false;
         }
@@ -929,7 +1000,7 @@ public function DomainTab()
     }
 
     /**
-     * @return string
+     * @return ?string
      */
     public function InboundUrl()
     {
@@ -938,7 +1009,7 @@ public function InboundUrl()
         if ($domain) {
             return $subdomain . '.' . $domain;
         }
-        return false;
+        return null;
     }
 
     /**
@@ -953,6 +1024,9 @@ public function getDomainFromHost()
             $base = Director::protocolAndHost();
         }
         $host = parse_url($base, PHP_URL_HOST);
+        if (!$host) {
+            return false;
+        }
         $hostParts = explode('.', $host);
         $parts = count($hostParts);
         if ($parts < 2) {
@@ -971,7 +1045,10 @@ public function getDomainFromEmail()
     {
         $email = SparkPostHelper::resolveDefaultFromEmail(null, false);
         if ($email) {
-            $domain = substr(strrchr($email, "@"), 1);
+            $domain = substr((string)strrchr($email, "@"), 1);
+            if (!$domain) {
+                return false;
+            }
             return $domain;
         }
         return false;
@@ -994,8 +1071,8 @@ public function getDomain()
     /**
      * Install domain form
      *
-     * @param CompositeField $fieldsd
-     * @return FormField
+     * @param CompositeField $fields
+     * @return void
      */
     public function InstallDomainForm(CompositeField $fields)
     {
@@ -1011,6 +1088,9 @@ public function InstallDomainForm(CompositeField $fields)
         )));
     }
 
+    /**
+     * @return HTTPResponse
+     */
     public function doInstallDomain()
     {
         if (!$this->CanConfigureApi()) {
@@ -1021,7 +1101,7 @@ public function doInstallDomain()
 
         $domain = $this->getDomain();
 
-        if (!$domain) {
+        if (!$domain || is_bool($domain)) {
             return $this->redirectBack();
         }
 
@@ -1038,8 +1118,8 @@ public function doInstallDomain()
     /**
      * Uninstall domain form
      *
-     * @param CompositeField $fieldsd
-     * @return FormField
+     * @param CompositeField $fields
+     * @return void
      */
     public function UninstallDomainForm(CompositeField $fields)
     {
@@ -1065,6 +1145,11 @@ public function UninstallDomainForm(CompositeField $fields)
         )));
     }
 
+    /**
+     * @param array<mixed> $data
+     * @param Form $form
+     * @return HTTPResponse
+     */
     public function doUninstallDomain($data, Form $form)
     {
         if (!$this->CanConfigureApi()) {
@@ -1075,7 +1160,7 @@ public function doUninstallDomain($data, Form $form)
 
         $domain = $this->getDomain();
 
-        if (!$domain) {
+        if (!$domain || is_bool($domain)) {
             return $this->redirectBack();
         }
 
diff --git a/src/SparkPostApiTransport.php b/src/SparkPostApiTransport.php
index 3eabb3c..1d7239d 100644
--- a/src/SparkPostApiTransport.php
+++ b/src/SparkPostApiTransport.php
@@ -16,6 +16,7 @@
 use Symfony\Contracts\HttpClient\ResponseInterface;
 use Symfony\Component\Mime\Header\UnstructuredHeader;
 use Symfony\Contracts\HttpClient\HttpClientInterface;
+use Symfony\Component\Mime\Header\ParameterizedHeader;
 use Symfony\Component\HttpClient\Response\MockResponse;
 use Symfony\Component\Mailer\Transport\AbstractApiTransport;
 use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
@@ -38,8 +39,17 @@ class SparkPostApiTransport extends AbstractApiTransport
      */
     private $apiClient;
 
+    /**
+     * @var array<mixed>
+     */
     private $apiResult;
 
+    /**
+     * @param SparkPostApiClient $apiClient
+     * @param HttpClientInterface|null $client
+     * @param EventDispatcherInterface|null $dispatcher
+     * @param LoggerInterface|null $logger
+     */
     public function __construct(SparkPostApiClient $apiClient, HttpClientInterface $client = null, EventDispatcherInterface $dispatcher = null, LoggerInterface $logger = null)
     {
         $this->apiClient = $apiClient;
@@ -98,24 +108,35 @@ protected function doSendApi(SentMessage $sentMessage, Email $email, Envelope $e
         return $response;
     }
 
+    /**
+     * @return array<mixed>
+     */
     public function getApiResult(): array
     {
         return $this->apiResult;
     }
 
-    private function getEndpoint(): ?string
+    /**
+     * @return string
+     */
+    private function getEndpoint(): string
     {
         return ($this->host ?: self::HOST) . ($this->port ? ':' . $this->port : '');
     }
 
+    /**
+     * @param Email $email
+     * @return array<array<mixed>>
+     */
     private function buildAttachments(Email $email): array
     {
         $result = [];
         foreach ($email->getAttachments() as $attachment) {
+            $preparedHeaders = $attachment->getPreparedHeaders();
             /** @var ParameterizedHeader $file */
-            $file = $attachment->getPreparedHeaders()->get('Content-Disposition');
+            $file = $preparedHeaders->get('Content-Disposition');
             /** @var ParameterizedHeader $type */
-            $type = $attachment->getPreparedHeaders()->get('Content-Type');
+            $type = $preparedHeaders->get('Content-Type');
 
             $result[] = [
                 'name' => $file->getParameter('filename'),
@@ -130,7 +151,7 @@ private function buildAttachments(Email $email): array
     /**
      * @param Email $email
      * @param Envelope $envelope
-     * @return array
+     * @return array<mixed>
      */
     private function getPayload(Email $email, Envelope $envelope): array
     {
@@ -198,7 +219,7 @@ private function getPayload(Email $email, Envelope $envelope): array
         }
         if ($emailHeaders->has('X-MC-Metadata')) {
             $metadataHeader = $emailHeaders->get('X-MC-Metadata');
-            $metadata = json_decode(self::getHeaderValue($metadataHeader), JSON_OBJECT_AS_ARRAY);
+            $metadata = json_decode(self::getHeaderValue($metadataHeader), true);
             $emailHeaders->remove('X-MC-Metadata');
         }
         if ($emailHeaders->has('X-MC-InlineCSS')) {
@@ -213,7 +234,7 @@ private function getPayload(Email $email, Envelope $envelope): array
         $msysHeader = [];
         if ($emailHeaders->has('X-MSYS-API')) {
             $msysHeaderObj = $emailHeaders->get('X-MSYS-API');
-            $msysHeader = json_decode(self::getHeaderValue($msysHeaderObj), JSON_OBJECT_AS_ARRAY);
+            $msysHeader = json_decode(self::getHeaderValue($msysHeaderObj), true);
             if (!empty($msysHeader['tags'])) {
                 $tags = array_merge($tags, $msysHeader['tags']);
             }
@@ -262,22 +283,23 @@ private function getPayload(Email $email, Envelope $envelope): array
             $bcc[] = array(
                 'email' => $bccEmail,
                 'name' => $bccName,
-                'header_to' => $primaryEmail ? $primaryEmail : $ccEmail,
+                'header_to' => $primaryEmail ? $primaryEmail : $bccEmail,
             );
         }
 
         $bodyHtml = $email->getHtmlBody();
         $bodyText = $email->getTextBody();
 
+        if ($bodyHtml && is_string($bodyHtml)) {
+            // If we ask to provide plain, use our custom method instead of the provided one
+            if (SparkPostHelper::config()->provide_plain) {
+                $bodyText = EmailUtils::convert_html_to_text($bodyHtml);
+            }
 
-        // If we ask to provide plain, use our custom method instead of the provided one
-        if ($bodyHtml && SparkPostHelper::config()->provide_plain) {
-            $bodyText = EmailUtils::convert_html_to_text($bodyHtml);
-        }
-
-        // Should we inline css
-        if (!$inlineCss && SparkPostHelper::config()->inline_styles) {
-            $bodyHtml = EmailUtils::inline_styles($bodyHtml);
+            // Should we inline css
+            if (!$inlineCss && SparkPostHelper::config()->inline_styles) {
+                $bodyHtml = EmailUtils::inline_styles($bodyHtml);
+            }
         }
 
         // Custom unsubscribe list
@@ -351,8 +373,9 @@ protected static function getHeaderValue(HeaderInterface $header = null)
      * Log message content
      *
      * @param Email $message
-     * @param array $results Results from the api
+     * @param array<mixed> $results Results from the api
      * @throws Exception
+     * @return void
      */
     protected function logMessageContent(Email $message, $results = [])
     {
@@ -382,9 +405,7 @@ protected function logMessageContent(Email $message, $results = [])
         $logContent .= 'Subject : ' . $subject . "\n";
         $logContent .= 'From : ' . print_r($message->getFrom(), true) . "\n";
         $logContent .= 'Headers:' . "\n" . $emailHeaders->toString() . "\n";
-        if (!empty($params['recipients'])) {
-            $logContent .= 'Recipients : ' . print_r($message->getTo(), true) . "\n";
-        }
+        $logContent .= 'Recipients : ' . print_r($message->getTo(), true) . "\n";
         $logContent .= 'Results:' . "\n";
         $logContent .= print_r($results, true) . "\n";
         $logContent .= '</pre>';
diff --git a/src/SparkPostController.php b/src/SparkPostController.php
index 07a6620..23c18b7 100644
--- a/src/SparkPostController.php
+++ b/src/SparkPostController.php
@@ -9,6 +9,7 @@
 use SilverStripe\Control\Controller;
 use SilverStripe\Control\HTTPRequest;
 use SilverStripe\Security\Permission;
+use SilverStripe\Control\HTTPResponse;
 use LeKoala\SparkPost\Api\SparkPostApiClient;
 
 /**
@@ -18,8 +19,19 @@
  */
 class SparkPostController extends Controller
 {
+    /**
+     * @var int
+     */
     protected $eventsCount = 0;
+
+    /**
+     * @var int
+     */
     protected $skipCount = 0;
+
+    /**
+     * @var array<string>
+     */
     private static $allowed_actions = [
         'incoming',
         'test',
@@ -29,17 +41,21 @@ class SparkPostController extends Controller
     /**
      * Inject public dependencies into the controller
      *
-     * @var array
+     * @var array<string,string>
      */
     private static $dependencies = [
         'logger' => '%$Psr\Log\LoggerInterface',
     ];
 
     /**
-     * @var Psr\Log\LoggerInterface
+     * @var \Psr\Log\LoggerInterface
      */
     public $logger;
 
+    /**
+     * @param HTTPRequest $req
+     * @return HTTPResponse|string
+     */
     public function index(HTTPRequest $req)
     {
         return $this->render([
@@ -52,6 +68,7 @@ public function index(HTTPRequest $req)
      * You can also see /resources/sample.json
      *
      * @param HTTPRequest $req
+     * @return string
      */
     public function test(HTTPRequest $req)
     {
@@ -65,7 +82,10 @@ public function test(HTTPRequest $req)
         } else {
             $data = file_get_contents(dirname(__DIR__) . '/resources/sample.json');
         }
-        $payload = json_decode($data, JSON_OBJECT_AS_ARRAY);
+        if (!$data) {
+            throw new Exception("Failed to get data");
+        }
+        $payload = json_decode($data, true);
         $payload['@headers'] = $req->getHeaders();
 
         $this->processPayload($payload, 'TEST');
@@ -195,6 +215,7 @@ public function configure_inbound_emails(HTTPRequest $req)
         } else {
             echo "Webhook already configured";
         }
+        return '';
     }
 
     /**
@@ -204,6 +225,7 @@ public function configure_inbound_emails(HTTPRequest $req)
      * @link https://www.sparkpost.com/blog/webhooks-beyond-the-basics/
      * @link https://support.sparkpost.com/customer/portal/articles/1976204-webhook-event-reference
      * @param HTTPRequest $req
+     * @return HTTPResponse
      */
     public function incoming(HTTPRequest $req)
     {
@@ -225,7 +247,7 @@ public function incoming(HTTPRequest $req)
             return $response;
         }
 
-        $payload = json_decode($json, JSON_OBJECT_AS_ARRAY);
+        $payload = json_decode($json, true);
 
         // Check credentials if defined
         $isAuthenticated = true;
@@ -274,10 +296,13 @@ public function incoming(HTTPRequest $req)
         }
 
         $response->setBody('OK');
-
         return $response;
     }
 
+    /**
+     * @param HTTPRequest $req
+     * @return void
+     */
     protected function authRequest(HTTPRequest $req)
     {
         $requestUser = $req->getHeader('php_auth_user');
@@ -310,8 +335,9 @@ protected function authRequest(HTTPRequest $req)
     /**
      * Process data
      *
-     * @param array $payload
+     * @param array<mixed> $payload
      * @param string $batchId
+     * @return void
      */
     protected function processPayload(array $payload, $batchId = null)
     {
@@ -333,14 +359,14 @@ protected function processPayload(array $payload, $batchId = null)
 
             // Invalid payload: it should always be an object with a msys key containing the event
             if ($ev === null) {
-                $this->getLogger()->warn("Invalid payload: " . substr(json_encode($r), 0, 100) . '...');
+                $this->getLogger()->warning("Invalid payload: " . substr((string)json_encode($r), 0, 100) . '...');
                 continue;
             }
 
             // Check type: it should be an object with the type as key
             $type = key($ev);
             if (!isset($ev[$type])) {
-                $this->getLogger()->warn("Invalid type $type in SparkPost payload");
+                $this->getLogger()->warning("Invalid type $type in SparkPost payload");
                 continue;
             }
             $data = $ev[$type];
@@ -385,7 +411,7 @@ protected function processPayload(array $payload, $batchId = null)
     /**
      * Get logger
      *
-     * @return Psr\SimpleCache\CacheInterface
+     * @return \Psr\Log\LoggerInterface
      */
     public function getLogger()
     {
diff --git a/src/SparkPostHelper.php b/src/SparkPostHelper.php
index 8cbf920..eac500a 100644
--- a/src/SparkPostHelper.php
+++ b/src/SparkPostHelper.php
@@ -29,7 +29,7 @@ class SparkPostHelper
     /**
      * Client instance
      *
-     * @var SparkPostApiClient
+     * @var ?\LeKoala\SparkPost\Api\SparkPostApiClient
      */
     protected static $client;
 
@@ -45,7 +45,7 @@ public static function getMailer()
 
     /**
      * @param MailerInterface $mailer
-     * @return AbstractTransport|SparkpostApiTransport
+     * @return \Symfony\Component\Mailer\Transport\AbstractTransport|SparkpostApiTransport
      */
     public static function getTransportFromMailer($mailer)
     {
@@ -77,6 +77,7 @@ public static function getClient()
             }
             self::$client = new SparkPostApiClient($key);
             if (Director::isDev()) {
+                //@phpstan-ignore-next-line
                 self::$client->setCurlOption(CURLOPT_VERBOSE, true);
             }
             if (Environment::getEnv("SPARKPOST_EU")) {
@@ -92,8 +93,7 @@ public static function getClient()
 
     /**
      * Get the api client instance
-     * @return LeKoala\SparkPost\Api\SparkPostApiClient
-     *
+     * @return \LeKoala\SparkPost\Api\SparkPostApiClient
      * @throws Exception
      */
     public static function getMasterClient()
@@ -162,46 +162,73 @@ public static function init()
         }
     }
 
+    /**
+     * @return mixed
+     */
     public static function getEnvApiKey()
     {
         return Environment::getEnv('SPARKPOST_API_KEY');
     }
 
+    /**
+     * @return mixed
+     */
     public static function getEnvMasterApiKey()
     {
         return Environment::getEnv('SPARKPOST_MASTER_API_KEY');
     }
 
+    /**
+     * @return mixed
+     */
     public static function getEnvSendingDisabled()
     {
         return Environment::getEnv('SPARKPOST_SENDING_DISABLED');
     }
 
+    /**
+     * @return mixed
+     */
     public static function getEnvEnableLogging()
     {
         return  Environment::getEnv('SPARKPOST_ENABLE_LOGGING');
     }
 
+    /**
+     * @return mixed
+     */
     public static function getEnvSubaccountId()
     {
         return  Environment::getEnv('SPARKPOST_SUBACCOUNT_ID');
     }
 
+    /**
+     * @return mixed
+     */
     public static function getSubaccountId()
     {
         return self::config()->subaccount_id;
     }
 
+    /**
+     * @return mixed
+     */
     public static function getEnvForceSender()
     {
         return Environment::getEnv('SPARKPOST_FORCE_SENDER');
     }
 
+    /**
+     * @return mixed
+     */
     public static function getWebhookUsername()
     {
         return self::config()->webhook_username;
     }
 
+    /**
+     * @return mixed
+     */
     public static function getWebhookPassword()
     {
         return self::config()->webhook_password;
@@ -210,7 +237,7 @@ public static function getWebhookPassword()
     /**
      * Register the transport with the client
      *
-     * @return SparkPostApiTransport The updated mailer
+     * @return Mailer The updated mailer
      * @throws Exception
      */
     public static function registerTransport()
@@ -279,7 +306,7 @@ public static function isEmailDomainReady($email)
      *
      * @param string $from
      * @param bool $createDefault
-     * @return string
+     * @return string|array<string,string>|false
      */
     public static function resolveDefaultFromEmail($from = null, $createDefault = true)
     {
@@ -302,7 +329,7 @@ public static function resolveDefaultFromEmail($from = null, $createDefault = tr
         }
         // Use admin email if set
         if ($adminEmail = Email::config()->admin_email) {
-            if (is_array($adminEmail) && count($adminEmail ?? []) > 0) {
+            if (is_array($adminEmail) && count($adminEmail) > 0) {
                 $email = array_keys($adminEmail)[0];
                 return [$email => $adminEmail[$email]];
             } elseif (is_string($adminEmail)) {
@@ -375,8 +402,8 @@ public static function isDefaultEmail($email)
     /**
      * Resolve default send to address
      *
-     * @param string $to
-     * @return string
+     * @param string|array<mixed>|null $to
+     * @return string|array<mixed>|null
      */
     public static function resolveDefaultToEmail($to = null)
     {
@@ -399,7 +426,7 @@ public static function resolveDefaultToEmail($to = null)
         if ($admin = Email::config()->admin_email) {
             return $admin;
         }
-        return false;
+        return null;
     }
 
     /**
diff --git a/src/api/SparkPostApiClient.php b/src/api/SparkPostApiClient.php
index 5193ac2..7850a98 100644
--- a/src/api/SparkPostApiClient.php
+++ b/src/api/SparkPostApiClient.php
@@ -54,7 +54,7 @@ class SparkPostApiClient
     /**
      * Your api key
      *
-     * @var string
+     * @var ?string
      */
     protected $key;
 
@@ -82,7 +82,7 @@ class SparkPostApiClient
     /**
      * Results from the api
      *
-     * @var array
+     * @var array<mixed>
      */
     protected $results = [];
 
@@ -96,7 +96,7 @@ class SparkPostApiClient
     /**
      * Client options
      *
-     * @var array
+     * @var array<mixed>
      */
     protected $curlOpts = [];
 
@@ -105,17 +105,20 @@ class SparkPostApiClient
      *
      * @param string $key Specify the string, or it will read env SPARKPOST_API_KEY or constant SPARKPOST_API_KEY
      * @param int $subaccount Specify a subaccount to limit data sent by the API
-     * @param array $curlOpts Additionnal options to configure the curl client
+     * @param array<mixed> $curlOpts Additionnal options to configure the curl client
      */
     public function __construct($key = null, $subaccount = null, $curlOpts = [])
     {
         if ($key) {
             $this->key = $key;
         } else {
-            $this->key = getenv('SPARKPOST_API_KEY');
+            $envkey = getenv('SPARKPOST_API_KEY');
+            if ($envkey) {
+                $this->key = $envkey;
+            }
         }
         if (getenv('SPARKPOST_EU')) {
-            $this->euEndpoint = getenv('SPARKPOST_EU');
+            $this->euEndpoint = boolval(getenv('SPARKPOST_EU'));
         } elseif (defined('SPARKPOST_EU')) {
             $this->euEndpoint = true;
         }
@@ -126,7 +129,7 @@ public function __construct($key = null, $subaccount = null, $curlOpts = [])
     /**
      * Get default options
      *
-     * @return array
+     * @return array<mixed>
      */
     public function getDefaultCurlOptions()
     {
@@ -156,7 +159,8 @@ public function getCurlOption($name)
      * Set an option
      *
      * @param string $name
-     * @return mixed
+     * @param mixed $value
+     * @return void
      */
     public function setCurlOption($name, $value)
     {
@@ -177,6 +181,7 @@ public function getKey()
      * Set the current api key
      *
      * @param string $key
+     * @return void
      */
     public function setKey($key)
     {
@@ -186,7 +191,7 @@ public function setKey($key)
     /**
      * Get the use of eu endpoint
      *
-     * @return string
+     * @return bool
      */
     public function getEuEndpoint()
     {
@@ -196,7 +201,8 @@ public function getEuEndpoint()
     /**
      * Set the use of eu endpoint
      *
-     * @param string $euEndpoint
+     * @param bool $euEndpoint
+     * @return void
      */
     public function setEuEndpoint($euEndpoint)
     {
@@ -216,7 +222,7 @@ public function getVerboseLog()
     /**
      * Get the logger
      *
-     * @return type
+     * @return callable
      */
     public function getLogger()
     {
@@ -227,6 +233,7 @@ public function getLogger()
      * Set a logging method
      *
      * @param callable $logger
+     * @return void
      */
     public function setLogger(callable $logger)
     {
@@ -247,6 +254,7 @@ public function getSubaccount()
      * Set subaccount id
      *
      * @param int $subaccount
+     * @return void
      */
     public function setSubaccount($subaccount)
     {
@@ -256,7 +264,7 @@ public function setSubaccount($subaccount)
     /**
      * Helper that handles dot notation
      *
-     * @param array $arr
+     * @param array<mixed> $arr
      * @param string $path
      * @param string $val
      * @return mixed
@@ -273,9 +281,9 @@ protected function setMappedValue(array &$arr, $path, $val)
     /**
      * Map data using a given mapping array
      *
-     * @param array $data
-     * @param array $map
-     * @return array
+     * @param array<mixed> $data
+     * @param array<mixed> $map
+     * @return array<mixed>
      */
     protected function mapData($data, $map)
     {
@@ -318,8 +326,8 @@ protected function mapData($data, $map)
      * 'inlineCss'
      *
      * @link https://developers.sparkpost.com/api/transmissions.html
-     * @param array $data
-     * @return array An array containing 3 keys: total_rejected_recipients, total_accepted_recipients, id
+     * @param array<mixed> $data
+     * @return array<mixed> An array containing 3 keys: total_rejected_recipients, total_accepted_recipients, id
      */
     public function createTransmission($data)
     {
@@ -359,7 +367,7 @@ public function createTransmission($data)
      * Get the detail of a transmission
      *
      * @param string $id
-     * @return array
+     * @return array<mixed>
      */
     public function getTransmission($id)
     {
@@ -370,7 +378,7 @@ public function getTransmission($id)
      * Delete a transmission
      *
      * @param string $id
-     * @return array
+     * @return array<mixed>
      */
     public function deleteTransmission($id)
     {
@@ -382,7 +390,7 @@ public function deleteTransmission($id)
      *
      * @param string $campaignId
      * @param string $templateId
-     * @return array
+     * @return array<mixed>
      */
     public function listTransmissions($campaignId = null, $templateId = null)
     {
@@ -446,8 +454,8 @@ public function listTransmissions($campaignId = null, $templateId = null)
      * [timestamp] =>  2050-01-01T11:57:36.000Z
      *
      * @deprecated
-     * @param array $params
-     * @return array
+     * @param array<mixed> $params
+     * @return array<mixed>
      */
     public function searchMessageEvents($params = [])
     {
@@ -524,8 +532,8 @@ public function searchMessageEvents($params = [])
      * "transactional" => "1"
      * "msg_size" => "48613"
      *
-     * @param array $params
-     * @return array
+     * @param array<mixed> $params
+     * @return array<mixed>
      */
     public function searchEvents($params = [])
     {
@@ -557,8 +565,8 @@ public function searchEvents($params = [])
      * ]
      * }
      *
-     * @param string $params
-     * @return array
+     * @param array<mixed> $params
+     * @return array<mixed>
      */
     public function createWebhook($params = [])
     {
@@ -570,10 +578,10 @@ public function createWebhook($params = [])
      *
      * @param string $name
      * @param string $target
-     * @param array $events
+     * @param array<mixed> $events
      * @param bool $auth Should we use basic auth ?
-     * @param array $credentials An array containing "username" and "password"
-     * @return type
+     * @param array<mixed> $credentials An array containing "username" and "password"
+     * @return array<mixed>
      */
     public function createSimpleWebhook($name, $target, array $events = null, $auth = false, $credentials = null)
     {
@@ -603,7 +611,7 @@ public function createSimpleWebhook($name, $target, array $events = null, $auth
      * List all webhooks
      *
      * @param string $timezone
-     * @return array
+     * @return array<mixed>
      */
     public function listAllWebhooks($timezone = null)
     {
@@ -618,7 +626,7 @@ public function listAllWebhooks($timezone = null)
      * Get a webhook
      *
      * @param string $id
-     * @return array
+     * @return array<mixed>
      */
     public function getWebhook($id)
     {
@@ -629,8 +637,8 @@ public function getWebhook($id)
      * Update a webhook
      *
      * @param string $id
-     * @param array $params
-     * @return array
+     * @param array<mixed> $params
+     * @return array<mixed>
      */
     public function updateWebhook($id, $params = [])
     {
@@ -641,7 +649,7 @@ public function updateWebhook($id, $params = [])
      * Delete a webhook
      *
      * @param string $id
-     * @return array
+     * @return array<mixed>
      */
     public function deleteWebhook($id)
     {
@@ -652,7 +660,7 @@ public function deleteWebhook($id)
      * Validate a webhook
      *
      * @param string $id
-     * @return array
+     * @return array<mixed>
      */
     public function validateWebhook($id)
     {
@@ -667,7 +675,7 @@ public function validateWebhook($id)
      *
      * @param string $id
      * @param int $limit
-     * @return array
+     * @return array<mixed>
      */
     public function webhookBatchStatus($id, $limit = 1000)
     {
@@ -678,7 +686,7 @@ public function webhookBatchStatus($id, $limit = 1000)
      * List an example of the event data that will be posted by a Webhook for the specified events.
      *
      * @param string $events bounce, delivery...
-     * @return array
+     * @return array<mixed>
      */
     public function getSampleEvents($events = null)
     {
@@ -692,8 +700,8 @@ public function getSampleEvents($events = null)
     /**
      * Create a sending domain
      *
-     * @param string $params
-     * @return array
+     * @param array<mixed> $params
+     * @return array<mixed>
      */
     public function createSendingDomain($params = [])
     {
@@ -704,7 +712,7 @@ public function createSendingDomain($params = [])
      * A simpler call to the api
      *
      * @param string $name
-     * @return array
+     * @return array<mixed>
      */
     public function createSimpleSendingDomain($name)
     {
@@ -717,7 +725,7 @@ public function createSimpleSendingDomain($name)
     /**
      * List all sending domains
      *
-     * @return array
+     * @return array<mixed>
      */
     public function listAllSendingDomains()
     {
@@ -728,7 +736,7 @@ public function listAllSendingDomains()
      * Get a sending domain
      *
      * @param string $id
-     * @return array
+     * @return array<mixed>
      */
     public function getSendingDomain($id)
     {
@@ -739,7 +747,7 @@ public function getSendingDomain($id)
      * Verify a sending domain - This will ask SparkPost to check if SPF and DKIM are valid
      *
      * @param string $id
-     * @return array
+     * @return array<mixed>
      */
     public function verifySendingDomain($id)
     {
@@ -753,8 +761,8 @@ public function verifySendingDomain($id)
      * Update a sending domain
      *
      * @param string $id
-     * @param array $params
-     * @return array
+     * @param array<mixed> $params
+     * @return array<mixed>
      */
     public function updateSendingDomain($id, $params = [])
     {
@@ -765,7 +773,7 @@ public function updateSendingDomain($id, $params = [])
      * Delete a sending domain
      *
      * @param string $id
-     * @return array
+     * @return array<mixed>
      */
     public function deleteSendingDomain($id)
     {
@@ -776,7 +784,7 @@ public function deleteSendingDomain($id)
      * Create an inbound domain
      *
      * @param string $domain
-     * @return array
+     * @return array<mixed>
      */
     public function createInboundDomain($domain)
     {
@@ -786,7 +794,7 @@ public function createInboundDomain($domain)
     /**
      * List all inbound domains
      *
-     * @return array
+     * @return array<mixed>
      */
     public function listInboundDomains()
     {
@@ -797,7 +805,7 @@ public function listInboundDomains()
      * Get details of an inbound domain
      *
      * @param string $domain
-     * @return array
+     * @return array<mixed>
      */
     public function getInboundDomain($domain)
     {
@@ -808,7 +816,7 @@ public function getInboundDomain($domain)
      * Delete an inbound domain
      *
      * @param string $domain
-     * @return array
+     * @return array<mixed>
      */
     public function deleteInboundDomain($domain)
     {
@@ -826,8 +834,8 @@ public function deleteInboundDomain($domain)
      * "domain": "email.example.com"
      * }
      *
-     * @param array|string $params
-     * @return array
+     * @param array<mixed>|string $params
+     * @return array<mixed>
      */
     public function createRelayWebhook($params)
     {
@@ -837,7 +845,7 @@ public function createRelayWebhook($params)
     /**
      * List all relay webhooks
      *
-     * @return array
+     * @return array<mixed>
      */
     public function listRelayWebhooks()
     {
@@ -848,7 +856,7 @@ public function listRelayWebhooks()
      * Get the details of a relay webhook
      *
      * @param int $id
-     * @return array
+     * @return array<mixed>
      */
     public function getRelayWebhook($id)
     {
@@ -859,8 +867,8 @@ public function getRelayWebhook($id)
      * Update a relay webhook
      *
      * @param int $id
-     * @param array $params
-     * @return array
+     * @param array<mixed> $params
+     * @return array<mixed>
      */
     public function updateRelayWebhook($id, $params)
     {
@@ -871,7 +879,7 @@ public function updateRelayWebhook($id, $params)
      * Delete a relay webhook
      *
      * @param int $id
-     * @return array
+     * @return array<mixed>
      */
     public function deleteRelayWebhook($id)
     {
@@ -881,7 +889,7 @@ public function deleteRelayWebhook($id)
     /**
      * Create a valid date for the API
      *
-     * @param string $time
+     * @param string|int $time
      * @param string $format
      * @return string Datetime in format of YYYY-MM-DDTHH:MM
      */
@@ -890,10 +898,16 @@ public function createValidDatetime($time, $format = null)
         if (!is_int($time)) {
             $time = strtotime($time);
         }
+        if (!$time) {
+            throw new Exception("Invalid time");
+        }
         if (!$format) {
             $dt = new DateTime('@' . $time);
         } else {
-            $dt = DateTime::createFromFormat($format, $time);
+            $dt = DateTime::createFromFormat((string)$format, (string)$time);
+        }
+        if (!$dt) {
+            throw new Exception("Invalid datetime");
         }
         return $dt->format(self::DATETIME_FORMAT);
     }
@@ -904,7 +918,7 @@ public function createValidDatetime($time, $format = null)
      * @param string $email
      * @param string $name
      * @param string $header_to
-     * @return array
+     * @return array<mixed>
      */
     public function buildAddress($email, $name = null, $header_to = null)
     {
@@ -925,7 +939,7 @@ public function buildAddress($email, $name = null, $header_to = null)
      *
      * @param string $string
      * @param string $header_to
-     * @return array
+     * @return array<mixed>
      */
     public function buildAddressFromString($string, $header_to = null)
     {
@@ -937,11 +951,11 @@ public function buildAddressFromString($string, $header_to = null)
     /**
      * Build a recipient
      *
-     * @param string|array $address
-     * @param array $tags
-     * @param array $metadata
-     * @param array $substitution_data
-     * @return array
+     * @param string|array<mixed> $address
+     * @param array<mixed> $tags
+     * @param array<mixed> $metadata
+     * @param array<mixed> $substitution_data
+     * @return array<mixed>
      * @throws Exception
      */
     public function buildRecipient($address, array $tags = null, array $metadata = null, array $substitution_data = null)
@@ -973,8 +987,8 @@ public function buildRecipient($address, array $tags = null, array $metadata = n
      *
      * @param string $endpoint
      * @param string $action
-     * @param array $data
-     * @return array
+     * @param array<mixed>|string $data
+     * @return array<mixed>
      * @throws Exception
      */
     protected function makeRequest($endpoint, $action = null, $data = null)
@@ -991,11 +1005,13 @@ protected function makeRequest($endpoint, $action = null, $data = null)
             $action = strtoupper($action);
         }
 
-        if ($action === self::METHOD_GET && !empty($data)) {
-            $endpoint .= '?' . http_build_query($data);
-        }
-        if ($action === self::METHOD_POST && is_array($data)) {
-            $data = json_encode($data);
+        if (is_array($data) && !empty($data)) {
+            if ($action === self::METHOD_GET) {
+                $endpoint .= '?' . http_build_query($data);
+            }
+            if ($action === self::METHOD_POST) {
+                $data = json_encode($data);
+            }
         }
 
         $header = [];
@@ -1020,12 +1036,18 @@ protected function makeRequest($endpoint, $action = null, $data = null)
         if ($this->getCurlOption('verbose')) {
             curl_setopt($ch, CURLOPT_VERBOSE, true);
             $verbose = fopen('php://temp', 'w+');
+            if ($verbose === false) {
+                throw new Exception("Failed to open stream");
+            }
             curl_setopt($ch, CURLOPT_STDERR, $verbose);
         }
 
         // This fixes ca cert issues if server is not configured properly
-        if (strlen(ini_get('curl.cainfo')) === 0) {
-            curl_setopt($ch, CURLOPT_CAINFO, \Composer\CaBundle\CaBundle::getBundledCaBundlePath());
+        $cainfo = ini_get('curl.cainfo');
+        if ($cainfo !== false) {
+            if (strlen($cainfo) === 0) {
+                curl_setopt($ch, CURLOPT_CAINFO, \Composer\CaBundle\CaBundle::getBundledCaBundlePath());
+            }
         }
 
         switch ($action) {
@@ -1043,6 +1065,9 @@ protected function makeRequest($endpoint, $action = null, $data = null)
         if (!$result) {
             throw new Exception('Error: "' . curl_error($ch) . '" - Code: ' . curl_errno($ch));
         }
+        if (is_bool($result)) {
+            throw new Exception("CURLOPT_RETURNTRANSFER was not set");
+        }
 
         if ($this->getCurlOption('verbose')) {
             rewind($verbose);
@@ -1073,15 +1098,18 @@ protected function makeRequest($endpoint, $action = null, $data = null)
                     // For invalid domains, append domain name to make error more useful
                     if ($item['code'] == 7001) {
                         $from = '';
-                        if (!is_array($data)) {
-                            $data = json_decode($data, JSON_OBJECT_AS_ARRAY);
+                        if (!is_array($data) && is_string($data)) {
+                            $data = json_decode($data, true);
                         }
                         if (isset($data['content']['from'])) {
                             $from = $data['content']['from'];
                         }
                         if ($from && is_string($from)) {
-                            $domain = substr(strrchr($from, "@"), 1);
-                            $message .= ' (' . $domain . ')';
+                            $fromat = strrchr($from, "@");
+                            if ($fromat) {
+                                $domain = substr($fromat, 1);
+                                $message .= ' (' . $domain . ')';
+                            }
                         }
                     }
 
@@ -1091,8 +1119,8 @@ protected function makeRequest($endpoint, $action = null, $data = null)
                             if (empty($data['recipients'])) {
                                 $message .= ' (empty recipients list)';
                             } else {
+                                $addresses = [];
                                 if (is_array($data['recipients'])) {
-                                    $addresses = [];
                                     foreach ($data['recipients'] as $recipient) {
                                         $addresses[] = json_encode($recipient['address']);
                                     }
@@ -1118,7 +1146,7 @@ protected function makeRequest($endpoint, $action = null, $data = null)
     /**
      * Get all results from the api
      *
-     * @return array
+     * @return array<mixed>
      */
     public function getResults()
     {
@@ -1128,7 +1156,7 @@ public function getResults()
     /**
      * Get last result
      *
-     * @return array
+     * @return array<mixed>
      */
     public function getLastResult()
     {