4 files changed, 128 insertions, 3 deletions
diff --git a/src/DTS/Errors.php b/src/DTS/Errors.php
new file mode 100644
index 0000000..3c1dd5d
--- /dev/null
+++ b/src/DTS/Errors.php
@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DTS;
+
+class Errors
+{
+    private $errors = [];
+
+    public function add(string $key, string $value): void
+    {
+        $this->errors[$key][] = $value;
+    }
+
+    public function get(string $key): array
+    {
+        return $this->errors[$key];
+    }
+
+    public function has(string $key): bool
+    {
+        return array_key_exists($key, $this->errors);
+    }
+
+    public function count(): int
+    {
+        return count($this->errors);
+    }
+}
diff --git a/src/DTS/Session.php b/src/DTS/Session.php
index 956f4e5..e5da42f 100644
--- a/src/DTS/Session.php
+++ b/src/DTS/Session.php
@@ -29,13 +29,13 @@ class Session
         }
     }
 
-    public function set(string $key, string $value): void
+    public function set(string $key, mixed $value): void
     {
         $this->session[$key] = $_SESSION[$key] = $value;
     }
 
-    public function get(string $key): ?string
+    public function get(string $key, mixed $default = null): mixed
     {
-        return $this->session[$key] ?? null;
+        return $this->session[$key] ?? $default;
     }
 }
diff --git a/src/DTS/Validated.php b/src/DTS/Validated.php
new file mode 100644
index 0000000..5df8af7
--- /dev/null
+++ b/src/DTS/Validated.php
@@ -0,0 +1,14 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DTS;
+
+class Validated
+{
+    public ?string $url;
+
+    public ?string $title;
+
+    public ?string $tag;
+}
diff --git a/src/DTS/Validator.php b/src/DTS/Validator.php
new file mode 100644
index 0000000..7629e3b
--- /dev/null
+++ b/src/DTS/Validator.php
@@ -0,0 +1,81 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DTS;
+
+use DTS\Errors;
+use DTS\Validated;
+
+class Validator
+{
+    public Errors $errors;
+
+    public Validated $validated;
+
+    function __construct(array $request) {
+        $this->errors = new Errors();
+
+        $this->validated = new Validated();
+
+        $this->validateUrl($request['url'], 8, 512);
+
+        $this->validateTitle($request['title'], 8, 256);
+
+        $this->validateTag($request['tag'], 2, 8);
+    }
+
+    private function validateUrl(string $url, int $minLength, int $maxLength): void
+    {
+        $url = trim($url);
+
+        if (filter_var($url, FILTER_VALIDATE_URL) === false) {
+            $this->errors->add('url', 'Must be a URL');
+        }
+
+        if (strlen($url) < $minLength  || strlen($url) > $maxLength) {
+            $this->errors->add('url', "Must be between $minLength and $maxLength in characters in length");
+        }
+
+        if (!$this->errors->has('url')) {
+            $this->validated->url = $url;
+        }
+    }
+
+    private function validateTitle(string $title, int $minLength, int $maxLength): void
+    {
+        $title = trim($title);
+
+        if ($title === '') {
+            return;
+        }
+
+        if (strlen($title) < $minLength  || strlen($title) > $maxLength) {
+            $this->errors->add('title', "Must be between $minLength and $maxLength in characters in length");
+        }
+
+        if (!$this->errors->has('tite')) {
+            $this->validated->title = $title;
+        }
+    }
+
+    private function validateTag(string $tag, int $minLength, int $maxLength): void
+    {
+        $tag = trim($tag);
+
+        if ($tag === '') {
+            return;
+        }
+
+        if (strlen($tag) < $minLength  || strlen($tag) > $maxLength) {
+            $this->errors->add('tag', "Must be between $minLength and $maxLength in characters in length");
+        }
+        if (preg_match('/\W/', $tag) === 1) {
+            $this->errors->add('tag', 'May only contain word characters');
+        }
+
+        if (!$this->errors->has('tag')) {
+            $this->validated->tag = strtolower($tag);
+        }
+    }
+}