From 3cb58ab6460048b5f9195155a119409018569e49 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lars=20Rune=20N=C3=B8stdal?= <larsnostdal@gmail.com>
Date: Wed, 19 Mar 2014 05:20:54 +0100
Subject: [PATCH] mk-HTMLCTemplate: New feature; client side templating. Still
 needs more work, but this is the gist of it.

---
 src/symbolicweb/handy_handlers.clj |  1 +
 src/symbolicweb/html_template.clj  | 48 ++++++++++++++++++++++++++++++
 src/symbolicweb/viewport.clj       |  1 +
 3 files changed, 50 insertions(+)

diff --git a/src/symbolicweb/handy_handlers.clj b/src/symbolicweb/handy_handlers.clj
index 6dfe449..aa5b5a0 100644
--- a/src/symbolicweb/handy_handlers.clj
+++ b/src/symbolicweb/handy_handlers.clj
@@ -180,6 +180,7 @@
                  assoc k (assoc entry :already-added? true))))]
 
      [:body {:id "_body"}
+      [:div {:id "_sw_htmlctemplates" :style "display: none;"}]
       [:noscript
        [:h3 "JavaScript needs to be enabled in your browser"]
        [:p [:a {:href "https://encrypted.google.com/search?hl=en&q=how%20to%20enable%20javascript"}
diff --git a/src/symbolicweb/html_template.clj b/src/symbolicweb/html_template.clj
index 2f621e6..e9537b7 100644
--- a/src/symbolicweb/html_template.clj
+++ b/src/symbolicweb/html_template.clj
@@ -56,6 +56,54 @@
 
 
 
+(defn mk-HTMLCTemplate [^String html-resource ^Fn content-fn & args]
+  "Like mk-HTMLTemplate, but does the templating client side; in the browser, using jQuery."
+  (let [resource-hash (str "_sw_htmlctemplate-" (hash html-resource))]
+    (mk-WidgetBase
+     (fn [^WidgetBase template-widget]
+       (vm-observe (.viewport template-widget) (.lifetime template-widget) true
+         #(when %3
+            ;; Add template to Viewport once. It will be cloned and filled in (templated) later.
+            (when-not (get (ensure (:html-templates @%3)) resource-hash)
+              (alter (:html-templates @%3) conj resource-hash)
+              (js-run template-widget
+                "$('#_sw_htmlctemplates').append($(" (js-handle-value html-resource false) ").attr('id', '" resource-hash "'));"))
+            (let [transformation-data (content-fn template-widget)]
+              (js-run template-widget
+                "$('#" (.id template-widget) "').replaceWith($('#" resource-hash "').clone().attr('id', '"
+                (.id template-widget) "'));")
+              (doseq [[^String selector content] (partition 2 transformation-data)]
+                (let [content-class (class content)]
+                  (cond
+                   (= java.lang.String content-class)
+                   (js-run template-widget
+                     "$('#" (.id template-widget) " > " selector "').text(" (js-handle-value content false) ");")
+
+                   (= clojure.lang.PersistentVector content-class)
+                   (let [cmd (first content)]
+                     (case cmd
+                       :attr
+                       (let [[^Keyword attr-key ^String attr-value] (rest content)]
+                         (js-run template-widget
+                           "$('#" (.id template-widget) " > " selector "').attr('" (name attr-key) "', "
+                           (js-handle-value attr-value false) ");"))
+
+                       :html
+                       (js-run template-widget
+                         "$('#" (.id template-widget) " > " selector "').html(" (js-handle-value (second content) false) ");")))
+
+                   (= symbolicweb.core.WidgetBase content-class)
+                   (do
+                     (js-run template-widget
+                       "$('#" (.id template-widget) " > " selector "').attr('id', '" (.id ^WidgetBase content) "');")
+                     (when-not (= content template-widget)
+                       (binding [*in-html-container?* template-widget]
+                         (attach-branch template-widget content))))))))))
+       (str "<div id='" (.id template-widget) "' style='display: none;'></div>"))
+     (apply hash-map args))))
+
+
+
 (defn ^WidgetBase mk-TemplateElement [^ValueModel value-model & args]
   "TemplateElements are meant to be used in context of HTMLContainer and its subtypes."
   (apply mk-he "%TemplateElement" value-model args))
diff --git a/src/symbolicweb/viewport.clj b/src/symbolicweb/viewport.clj
index 6e3a5bf..7d4a271 100644
--- a/src/symbolicweb/viewport.clj
+++ b/src/symbolicweb/viewport.clj
@@ -41,6 +41,7 @@
                              :rest-css-entries (ref {})
                              :rest-js-entries (ref {})
                              :rest-head-entries (ref [])
+                             :html-templates (ref #{}) ;; mk-HTMLCTemplate
 
                              :session session
                              :root-element root-widget ;; TODO: Rename...