Add search functionality

jumpapp/classes/SearchEngines.php

@@ -0,0 +1,82 @@
+<?php
+
+namespace Jump;
+
+use \Exception;
+
+/**
+ * Loads and validates the search engines defined in searchengines.json.
+ *
+ * @author Dale Davies <dale@daledavies.co.uk>
+ * @license MIT
+ */
+class SearchEngines {
+    private array $default;
+    private string $searchfilelocation;
+    private array $loadedsearchengines;
+
+    /**
+     * Automatically load searchengines.json on instantiation.
+     */
+    public function __construct(private Config $config, private Cache $cache) {
+        $this->config = $config;
+        $this->loadedsearchengines = [];
+        $this->searchfilelocation = $this->config->get('searchenginesfile');
+        $this->cache = $cache;
+
+        // Retrieve search engines from cache. Load from json file if not cached or
+        // the cache has expired.
+        $this->loadedsearchengines = $this->cache->load(cachename: 'searchengines', callback: function() {
+            return $this->load_search_engines_from_json();
+        });
+
+    }
+    /**
+     * Try to load and validate the list of search engines from searchengines.json.
+     *
+     * Throws an exception if the file cannot be loaded, is empty, or cannot
+     * be decoded to an array.
+     *
+     * @return array AArray of parsed/validated search engine information from searchengines.json
+     * @throws Exception If searchengines.json cannot be found.
+     */
+    private function load_search_engines_from_json(): array {
+        $searchengines = [];
+        $rawjson = file_get_contents($this->searchfilelocation);
+        if ($rawjson === false) {
+            throw new Exception('There was a problem loading the searchengines.json file');
+        }
+        if ($rawjson === '') {
+            throw new Exception('The searchengines.json file is empty');
+        }
+        // Do some checks to see if the JSON decodes into something
+        // like what we expect to see...
+        $decodedjson = json_decode($rawjson);
+
+        if (!is_array($decodedjson)) {
+            throw new Exception('The searchengines.json file is invalid');
+        }
+
+        // Build a new array using the values we need...
+        foreach ($decodedjson as $item) {
+            if (!isset($item->name, $item->url)) {
+                throw new Exception('The searchengines.json does not contain the "name" or "url" properties');
+            }
+            $searchengine = new \stdClass();
+            $searchengine->name = $item->name;
+            $searchengine->url = $item->url;
+            $searchengines[] = $searchengine;
+        }
+
+        return $searchengines;
+    }
+
+    /**
+     * Get the list of loaded search engines.
+     *
+     * @return array Array of parsed/validated search engine information from searchengines.json
+     */
+    public function get_search_engines() {
+        return $this->loadedsearchengines;
+    }
+}