Move hardcoded summary options to configuration file

Fixes #175

README.md

@@ -144,7 +144,7 @@ Use the `blogCategories` component to display a list of blog post categories wit
 
 The component injects the following variables to the page where it's used:
 
-* **categoryPage** - contains the value of the `categoryPage` component's property. 
+* **categoryPage** - contains the value of the `categoryPage` component's property.
 * **categories** - a list of blog categories loaded from the database.
 * **currentCategorySlug** - slug of the current category. This property is used for marking the current category in the category list.
 
@@ -183,6 +183,16 @@ The component can be used on any page, it will hijack the entire page cycle to d
     ==
     <!-- This markup will never be displayed -->
 
+## Configuration
+
+To overwrite the default configuration create a `config/rainlab/blog/config.php`. You can return only values you want to override.
+
+### Summary
+
+A summary attribute is generated for each post.
+
+If you enter an excerpt manually, it gets used as summary. Alternatively, you can use the `summary_separator` (default is `<!-- more -->`) to mark the end of the summary. If a post contains no separator, the text gets truncated after the number of characters specified in `summary_default_length` (default is 600 characters).
+
 ## Markdown guide
 
 October supports [standard markdown syntax](http://daringfireball.net/projects/markdown/) as well as [extended markdown syntax](http://michelf.ca/projects/php-markdown/extra/)
@@ -205,7 +215,7 @@ Markdown extra makes it possible to use fenced code blocks. With fenced code blo
     ```
     Code goes here
     ```
-    
+
 You can also use the `~` symbol:
 
     ~~~
@@ -219,8 +229,8 @@ A *simple* table can be defined as follows:
 ```
 First Header  | Second Header
 ------------- | -------------
-Content Cell  | Content Cell 
-Content Cell  | Content Cell 
+Content Cell  | Content Cell
+Content Cell  | Content Cell
 ```
 
 If you want to you can also add a leading and tailing pipe:

config/config.php

@@ -0,0 +1,18 @@
+<?php
+
+return [
+
+    /*
+    |--------------------------------------------------------------------------
+    | Summary Config
+    |--------------------------------------------------------------------------
+    |
+    | Specify a custom tag and length for blog post summaries
+    |
+    */
+
+    'summary_separator' => '<!-- more -->',
+
+    'summary_default_length' => 600
+
+];

models/Post.php

@@ -4,6 +4,7 @@
 use Html;
 use Lang;
 use Model;
+use Config;
 use Markdown;
 use BackendAuth;
 use Carbon\Carbon;
@@ -371,12 +372,13 @@ public function scopeFilterCategories($query, $categories)
      */
     public function getHasSummaryAttribute()
     {
-        $more = '<!-- more -->';
+        $more = Config::get('rainlab.blog::summary_separator', '<!-- more -->');
+        $length = Config::get('rainlab.blog::summary_default_length', 600);
 
         return (
             !!strlen(trim($this->excerpt)) ||
             strpos($this->content_html, $more) !== false ||
-            strlen(Html::strip($this->content_html)) > 600
+            strlen(Html::strip($this->content_html)) > $length
         );
     }
 
@@ -394,14 +396,17 @@ public function getSummaryAttribute()
             return $excerpt;
         }
 
-        $more = '<!-- more -->';
+        $more = Config::get('rainlab.blog::summary_separator', '<!-- more -->');
+
         if (strpos($this->content_html, $more) !== false) {
             $parts = explode($more, $this->content_html);
 
             return array_get($parts, 0);
         }
 
-        return Html::limit($this->content_html, 600);
+        $length = Config::get('rainlab.blog::summary_default_length', 600);
+
+        return Html::limit($this->content_html, $length);
     }
 
     //