initial commit of validation classes.

system/validation/rules/uniqueness_of.php

@@ -0,0 +1,60 @@
+<?php namespace System\Validation\Rules;
+
+use System\DB;
+use System\DB\Eloquent;
+use System\Validation\Rule;
+
+class Uniqueness_Of extends Rule {
+
+	/**
+	 * The database table that should be checked.
+	 *
+	 * @var string
+	 */
+	public $table;
+
+	/**
+	 * The database column that should be checked.
+	 *
+	 * @var string
+	 */
+	public $column;
+
+	/**
+	 * Evaluate the validity of an attribute.
+	 *
+	 * @param  string  $attribute
+	 * @param  array   $attributes
+	 * @return void
+	 */
+	public function check($attribute, $attributes)
+	{
+		if ( ! array_key_exists($attribute, $attributes))
+		{
+			return true;
+		}
+
+		if (is_null($this->column))
+		{
+			$this->column = $attribute;
+		}
+
+		return DB::table(Eloquent::table($this->table)->where($this->column, '=', $attributes[$attribute])->count() == 0;
+	}
+
+	/**
+	 * Set the database table and column.
+	 *
+	 * @param  string  $table
+	 * @param  string  $column
+	 * @return Uniqueness_Of
+	 */
+	public function on($table, $column = null)
+	{
+		$this->table = $table;
+		$this->column = $column;
+
+		return $this;
+	}
+
+}