Experimental code for issue #452

app/Generator/Chart/Basic/ChartJsGenerator.php

@@ -0,0 +1,64 @@
+<?php
+/**
+ * ChartJsGenerator.php
+ * Copyright (C) 2016 thegrumpydictator@gmail.com
+ *
+ * This software may be modified and distributed under the terms of the
+ * Creative Commons Attribution-ShareAlike 4.0 International License.
+ *
+ * See the LICENSE file for details.
+ */
+
+declare(strict_types = 1);
+
+namespace FireflyIII\Generator\Chart\Basic;
+
+/**
+ * Class ChartJsGenerator
+ *
+ * @package FireflyIII\Generator\Chart\Basic
+ */
+class ChartJsGenerator implements GeneratorInterface
+{
+
+    /**
+     * Will generate a Chart JS compatible array from the given input. Expects this format:
+     *
+     * 0: [
+     *    'label' => 'label of set',
+     *    'entries' =>
+     *        [
+     *         'label-of-entry' => 'value'
+     *        ]
+     *    ]
+     * 1: [
+     *    'label' => 'label of another set',
+     *    'entries' =>
+     *        [
+     *         'label-of-entry' => 'value'
+     *        ]
+     *    ]
+     *
+     *
+     * @param array $data
+     *
+     * @return array
+     */
+    public function multiSet(array $data): array
+    {
+        $chartData = [
+            'count'    => count($data),
+            'labels'   => array_keys($data[0]['entries']), // take ALL labels from the first set.
+            'datasets' => [],
+        ];
+
+        foreach ($data as $set) {
+            $chartData['datasets'][] = [
+                'label' => $set['label'],
+                'data'  => array_values($set['entries']),
+            ];
+        }
+
+        return $chartData;
+    }
+}

app/Generator/Chart/Basic/GeneratorInterface.php

@@ -0,0 +1,48 @@
+<?php
+/**
+ * GeneratorInterface.php
+ * Copyright (C) 2016 thegrumpydictator@gmail.com
+ *
+ * This software may be modified and distributed under the terms of the
+ * Creative Commons Attribution-ShareAlike 4.0 International License.
+ *
+ * See the LICENSE file for details.
+ */
+
+declare(strict_types = 1);
+
+namespace FireflyIII\Generator\Chart\Basic;
+
+/**
+ * Interface GeneratorInterface
+ *
+ * @package FireflyIII\Generator\Chart\Basic
+ */
+interface GeneratorInterface
+{
+    /**
+     * Will generate a Chart JS compatible array from the given input. Expects this format:
+     *
+     * 0: [
+     *    'label' => 'label of set',
+     *    'entries' =>
+     *        [
+     *         'label-of-entry' => 'value'
+     *        ]
+     *    ]
+     * 1: [
+     *    'label' => 'label of another set',
+     *    'entries' =>
+     *        [
+     *         'label-of-entry' => 'value'
+     *        ]
+     *    ]
+     *
+     *
+     * @param array $data
+     *
+     * @return array
+     */
+    public function multiSet(array $data): array;
+
+}