Add ability to preview notes without publishing

Resolves #604

Web/Models/Entities/Note.php

@@ -75,8 +75,18 @@ class Note extends Postable
             "underline",
         ]);
     
+        $source = NULL;
+        if(is_null($this->getRecord())) {
+            if(isset($this->changes["source"]))
+                $source = $this->changes["source"];
+            else
+                throw new \LogicException("Can't render note without content set.");
+        } else {
+            $source = $this->getRecord()->source;
+        }
+        
         $purifier = new HTMLPurifier($config);
-        return $purifier->purify($this->getRecord()->source);
+        return $purifier->purify($source);
     }
     
     function getName(): string
@@ -91,6 +101,9 @@ class Note extends Postable
     
     function getText(): string
     {
+        if(is_null($this->getRecord()))
+            return $this->renderHTML();
+        
         $cached = $this->getRecord()->cached_content;
         if(!$cached) {
             $cached = $this->renderHTML();

Web/Presenters/NotesPresenter.php

@@ -46,6 +46,29 @@ final class NotesPresenter extends OpenVKPresenter
         $this->template->note     = $note;
     }
     
+    function renderPreView(): void
+    {
+        $this->assertUserLoggedIn();
+        $this->willExecuteWriteAction();
+    
+        if($_SERVER["REQUEST_METHOD"] !== "POST") {
+            header("HTTP/1.1 400 Bad Request");
+            exit;
+        }
+        
+        if(empty($this->postParam("html")) || empty($this->postParam("title"))) {
+            header("HTTP/1.1 400 Bad Request");
+            exit(tr("note_preview_empty_err"));
+        }
+    
+        $note = new Note;
+        $note->setSource($this->postParam("html"));
+        
+        $this->flash("info", tr("note_preview_warn"), tr("note_preview_warn_details"));
+        $this->template->title = $this->postParam("title");
+        $this->template->html  = $note->getText();
+    }
+    
     function renderCreate(): void
     {
         $this->assertUserLoggedIn();

Web/Presenters/templates/Notes/Create.xml

@@ -17,6 +17,7 @@
         
         <input type="hidden" name="hash" value="{$csrfToken}" />
         <button class="button">{_save}</button>
+        <a href="javascript:openPreviewWindow()" style="float: right;">{_note_preview}</a>
     </form>
     
     {script "js/node_modules/monaco-editor/min/vs/loader.js"}
@@ -38,5 +39,20 @@
         document.querySelector("#noteFactory").addEventListener("submit", function() {
             document.querySelector("textarea").value = window._editor.getValue();
         });
+
+        window._preview = undefined;
+        function openPreviewWindow() {
+            if(typeof window._preview != "undefined") {
+                window._preview.close();
+                window._preview = undefined;
+            }
+
+            window._preview = window.open("data:text/html,", "_blank", { popup: true });
+            window._preview.document.write(`<style>form { display: none; }</style><form action="${ location.origin }/notes/prerender" method="POST" enctype="multipart/form-data"><input name="title" /><input name="html" /><input name="hash" /></form>`);
+            window._preview.document.querySelector("input[name=title]").value = document.querySelector("input[name=name]").value;
+            window._preview.document.querySelector("input[name=html]").value = window._editor.getValue();
+            window._preview.document.querySelector("input[name=hash]").value = document.querySelector("meta[name=csrf]").attributes.value.value;
+            window._preview.document.querySelector("form").submit();
+        }
     </script>
 {/block}

Web/Presenters/templates/Notes/PreView.xml

@@ -0,0 +1,37 @@
+{extends "../@layout.xml"}
+
+{block title}
+    {$title}
+{/block}
+
+{block header}
+    {$title}
+{/block}
+
+{block content}
+    <style>
+        .sidebar {
+            display: none;
+        }
+
+        .page_header {
+            display: none;
+        }
+
+        .page_content {
+            display: unset;
+            width: unset;
+        }
+
+        .page_body {
+            width: unset;
+            float: unset;
+        }
+
+        .page_footer {
+            display: none;
+        }
+    </style>
+
+    {$html|noescape}
+{/block}

Web/routes.yml

@@ -241,6 +241,8 @@ routes:
       handler: "Notes->list"
     - url: "/note{num}_{num}"
       handler: "Notes->view"
+    - url: "/notes/prerender"
+      handler: "Notes->preView"
     - url: "/notes/create"
       handler: "Notes->create"
     - url: "/note{num}_{num}/edit"

locales/en.strings

@@ -357,6 +357,10 @@
 "notes_one" = "$1 note";
 "notes_other" = "$1 notes";
 "notes_start_screen" = "With notes, you can share your events with friends and see what's going on with them.";
+"note_preview" = "Preview draft";
+"note_preview_warn" = "Preview mode active";
+"note_preview_warn_details" = "Notes may change their behaviour or looks after being saved. Also, try not to use preview very often.";
+"note_preview_empty_err" = "Preview of empty or nameless note? Why, Mr. White?";
 
 "notes_list_zero" = "No notes found";
 "notes_list_one" = "$1 note found";

locales/ru.strings

@@ -383,6 +383,10 @@
 "edit_note" = "Редактировать заметку";
 "actions" = "Действия";
 "notes_start_screen" = "С помощью заметок Вы можете делиться событиями из жизни с друзьями, а так же быть в курсе того, что происходит у них.";
+"note_preview" = "Предпросмотр";
+"note_preview_warn" = "Это всего лишь предпросмотр";
+"note_preview_warn_details" = "После сохранения заметки могут выглядеть иначе. К тому же, не вызывайте предпросмотр слишком часто.";
+"note_preview_empty_err" = "Зачем вам предпросмотр для заметки без имени или содержания?";
 
 "edited" = "Отредактировано";