Initial support for importing supplier costs

app/Traits/Import.php

@@ -0,0 +1,43 @@
+<?php
+
+/**
+ * Import from files
+ */
+namespace App\Traits;
+
+use Illuminate\Support\Collection;
+
+trait Import
+{
+	protected Collection $_columns;
+
+	/**
+	 * Return the columns from the file that we'll work with.
+	 * This creates an index of the position of each header in the file, which we use to find an value by getColumnKey()
+	 *
+	 * @param string $line
+	 * @return Collection
+	 * @throws \Exception
+	 */
+	private function setColumns(string $line): Collection
+	{
+		// If columns is not set, then this is an error
+		if (! $this->columns)
+			throw new \Exception('ERROR: Columns must be set before calling setColumns()');
+
+		$this->_columns = collect(explode(',',strtolower($line)))->filter();
+
+		return $this->_columns->intersect($this->columns);
+	}
+
+	/**
+	 * Get the index for the column in the file
+	 *
+	 * @param string $key
+	 * @return mixed
+	 */
+	private function getColumnKey(string $key)
+	{
+		return $this->_columns->search($this->columns->get($key));
+	}
+}