[APISDK-5] Added device fingerprint builder as frontend service

src/Exception/FrontendException.php

@@ -0,0 +1,16 @@
+<?php
+
+    namespace RatePAY\Exception;
+
+    class FrontendException extends ExceptionAbstract
+    {
+
+        /**
+         * @param string $message
+         */
+        public function __construct($message)
+        {
+            parent::__construct("Frontend exception : " . $message);
+        }
+
+    }

src/Frontend/DeviceFingerprintBuilder.php

@@ -0,0 +1,128 @@
+<?php
+
+namespace RatePAY\Frontend;
+
+use RatePAY\Exception\FrontendException;
+
+class DeviceFingerprintBuilder
+{
+
+    /**
+     * DFP Snippet Id (vendor)
+     *
+     * @var string
+     */
+    private $snippetId;
+
+    /**
+     * Location of DFP snippet
+     *
+     * @var string
+     */
+    private $location = "checkout";
+
+    /**
+     * DFP token
+     *
+     * @var string
+     */
+    private $token;
+
+    /**
+     * DFP URI
+     *
+     * @var string
+     */
+    private $uri = "//d.ratepay.com";
+
+
+    /**
+     * DeviceFingerprintBuilder constructor.
+     *
+     * @param $uniqueIdentifier
+     */
+    public function __construct($snippetId = "", $uniqueIdentifier = "")
+    {
+        if (!empty($snippetId)) {
+            $this->setSnippetId($snippetId);
+        } else {
+            throw new FrontendException("DeviceFingerprintBuilder: Snippet id must be set");
+        }
+
+        if (!empty($uniqueIdentifier)) {
+            $this->createToken($uniqueIdentifier);
+        } else {
+            throw new FrontendException("DeviceFingerprintBuilder: Transaction identifier must be set");
+        }
+    }
+
+    /**
+     * @param string $snippetId
+     */
+    public function setSnippetId($snippetId)
+    {
+        $this->snippetId = $snippetId;
+    }
+
+    /**
+     * Sets DFP token
+     *
+     * @param string $token
+     */
+    public function setToken($token)
+    {
+        $this->token = $token;
+    }
+
+    /**
+     * Returns DFP token
+     *
+     * @return string
+     */
+    public function getToken()
+    {
+        return $this->token;
+    }
+
+    /**
+     * Returns DFP snippet code (JS code)
+     * @return string
+     */
+    public function getDfpSnippetCode($smarty = false)
+    {
+        $snippet = sprintf(
+            (!$smarty) ? "<script language=\"JavaScript\">var di = %s;</script>" : "<script language=\"JavaScript\">{literal}var di = %s;{/literal}</script>",
+            json_encode([
+                't' => $this->token,
+                'v' => $this->snippetId,
+                'l' => $this->location
+            ])
+        );
+
+        $snippet .= sprintf(
+            "<script type=\"text/javascript\" src=\"%s/%s/di.js\"></script>",
+            $this->uri,
+            $this->snippetId
+        );
+
+        $snippet .= sprintf(
+            "<noscript><link rel=\"stylesheet\" type=\"text/css\" href=\"%s/di.css?t=%s&v=%s&l=%s\"></noscript>",
+            $this->uri,
+            $this->token,
+            $this->snippetId,
+            $this->location
+        );
+
+        return $snippet;
+    }
+
+    /**
+     * Creates unique token
+     *
+     * @param $uniqueIdentifier
+     */
+    private function createToken($uniqueIdentifier) {
+        $this->token = md5($this->snippetId . "_" . $uniqueIdentifier . "_" . microtime());
+    }
+
+}