1 files changed, 193 insertions, 0 deletions
diff --git a/src/Model/Collection.php b/src/Model/Collection.php
new file mode 100644
index 0000000..8715f07
--- /dev/null
+++ b/src/Model/Collection.php
@@ -0,0 +1,193 @@
+<?php
+
+namespace App\Model;
+
+use App\Model\Model;
+use ArrayAccess;
+use Countable;
+use Exception;
+use Iterator;
+
+/**
+ * A collection of models
+ *
+ * @author Phil Burton <phil@pgburton.com>
+ */
+class Collection implements ArrayAccess, Iterator, Countable
+{
+    /**
+     * Raw array of models
+     *
+     * @var Model[]
+     */
+    protected $models;
+
+    /**
+     * Current index of array
+     *
+     * @var int
+     */
+    protected $position;
+
+    /**
+     * Initalise the collection
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @param $array
+     */
+    public function __construct($array = [])
+    {
+        // Initalise Index
+        $this->position = 0;
+
+        // Initalise empty array
+        $this->setFromArray($array);
+    }
+
+    /**
+     * Reset array to a new array of models
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @param array $array
+     */
+    public function setFromArray(array $array)
+    {
+        $this->models = [];
+        foreach ($array as $model) {
+            $this->models[] = $model;
+        }
+    }
+
+    /**
+     * Set the offset
+     * Only allow values that are an instance of User
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @param mixed $offset
+     * @param mixed $value
+     */
+    public function offsetSet($offset, $value)
+    {
+        if (!$value instanceof Model) {
+            throw new Exception(
+                'Collection expects a value of type ' . Model::class . ', ' . gettype($value) . ' given'
+            );
+        }
+        if (is_null($offset)) {
+            $this->models[] = $value;
+        } else {
+            $this->models[$offset] = $value;
+        }
+    }
+
+    /**
+     * Return true if the given offset exists
+     * Otherwise return false
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @param mixed $offset
+     */
+    public function offsetExists($offset)
+    {
+        return isset($this->models[$offset]);
+    }
+
+    /**
+     * Unset a given offset
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @param mixed $offset
+     */
+    public function offsetUnset($offset)
+    {
+        unset($this->models[$offset]);
+    }
+
+    /**
+     * Get the value at a given offset
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @param mixed $offset
+     */
+    public function offsetGet($offset)
+    {
+        return isset($this->models[$offset]) ? $this->models[$offset] : null;
+    }
+
+    /**
+     * Return current user
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @return Model
+     */
+    public function current()
+    {
+        return $this->models[$this->position];
+    }
+
+    /**
+     * Return true if the current index exists in user array
+     * Otherwise return false
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @return bool
+     */
+    public function valid()
+    {
+        return isset($this->models[$this->position]);
+    }
+
+    /**
+     * Reset index back to 0
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     */
+    public function rewind()
+    {
+        $this->position = 0;
+    }
+
+    /**
+     * Return the current index
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @return int
+     */
+    public function key()
+    {
+        return $this->position;
+    }
+
+    /**
+     * Increment index by 1
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     */
+    public function next()
+    {
+        ++$this->position;
+    }
+
+    /**
+     * Create and return new collection of the merged arrays from thsi and a given collection
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @param Collection $collection
+     * @return Collection
+     */
+    public function merge(Collection $collection): Collection
+    {
+        return new Collection(array_merge($collection->toArray(), $this->toArray()));
+    }
+
+    /**
+     * Return count of users
+     *
+     * @author Phil Burton <phil@pgburton.com>
+     * @return int
+     */
+    public function count(): int
+    {
+        return count($this->models);
+    }
+}