/**
     * Update the specified resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  int  $id
     * @return \Illuminate\Http\Response
     */
    public function update(Request $request, $id)
    {
        // Validate the data
        $post = Post::find($id);
        $categories = Category::pluck('name','id');

        $this->validate($request, array(
                'title' => 'required|max:255',
                'slug'  => 'required',
                'category_id' => 'required|integer',
                'body'  => 'required'
        ));


        $post = Post::find($id);

        $post->title = $request->input('title');
        $post->slug = $request->input('slug');
        $post->category_id = $request->input('category_id');
        $post->user_id = Auth::id();
        $post->body = $request->input('body');

        if ($request->hasFile('featured_img')) {
            // Ajoute la nouvelle photo
            $image = $request->file('featured_img');
            $filename = time() . '.' . $image->getClientOriginalExtension();
            $location = public_path('img/' . $filename);
            Image::make($image)->fit(1200, 500)->save($location);
            $oldFilename = $post->image;
            // Met à jour la BDD
            $post->image = $filename;
            // Efface l'ancienne photo
            Storage::delete($oldFilename);

        }

        $post->save();

        Session::flash('success', "L'article à été correctement mis à jour.");

        return redirect()->route('posts.index');
    }