move language detection to a plugin, remove config.php constant

plugins/af_lang_detect/init.php

@@ -0,0 +1,46 @@
+<?php
+class Af_Lang_Detect extends Plugin {
+	private $host;
+	private $lang;
+
+	function about() {
+		return array(1.0,
+			"Detect article language",
+			"fox");
+	}
+
+	function init($host) {
+		$this->host = $host;
+
+		$host->add_hook($host::HOOK_ARTICLE_FILTER, $this);
+
+		require_once __DIR__ . "/languagedetect/LanguageDetect.php";
+
+		$this->lang = new Text_LanguageDetect();
+		$this->lang->setNameMode(2);
+	}
+
+	function hook_article_filter($article) {
+
+		if ($this->lang) {
+			$entry_language = $this->lang->detect($article['title'] . " " . $article['content'], 1);
+
+			if (count($entry_language) > 0) {
+				$possible = array_keys($entry_language);
+				$entry_language = $possible[0];
+
+				_debug("detected language: $entry_language");
+
+				$article["language"] = $entry_language;
+			}
+		}
+
+		return $article;
+	}
+
+	function api_version() {
+		return 2;
+	}
+
+}
+?>