From 73344d0dbfd38e9512091a8156ccda784cc474a7 Mon Sep 17 00:00:00 2001
From: Bodil Stokke <bodil@bodil.org>
Date: Mon, 12 Nov 2018 16:29:48 +0000
Subject: [PATCH] Build a virtual DOM structure.

---
 clippy.toml                |  5 ++++
 macros/src/declare.rs      | 59 +++++++++++++++++++++++++++++++++-----
 typed-html/src/bin/main.rs |  2 ++
 typed-html/src/elements.rs | 23 +++++++++++++--
 4 files changed, 80 insertions(+), 9 deletions(-)
 create mode 100644 clippy.toml

diff --git a/clippy.toml b/clippy.toml
new file mode 100644
index 0000000..d6f2aca
--- /dev/null
+++ b/clippy.toml
@@ -0,0 +1,5 @@
+blacklisted-names = []
+cyclomatic-complexity-threshold = 100
+single-char-binding-names-threshold = 15
+# I HAVE THE POWER OF OLEG
+type-complexity-threshold = 999999
diff --git a/macros/src/declare.rs b/macros/src/declare.rs
index 6058b39..197b4b6 100644
--- a/macros/src/declare.rs
+++ b/macros/src/declare.rs
@@ -96,11 +96,6 @@ impl Declare {
 
         let mut body = TokenStream::new();
 
-        body.extend(quote!(
-            pub attrs: $attr_type_name,
-            pub data_attributes: std::collections::BTreeMap<String, String>,
-        ));
-
         for (child_name, child_type, _) in self.req_children() {
             body.extend(quote!( pub $child_name: Box<$child_type>, ));
         }
@@ -112,6 +107,8 @@ impl Declare {
 
         quote!(
             pub struct $elem_name {
+                pub attrs: $attr_type_name,
+                pub data_attributes: std::collections::BTreeMap<String, String>,
                 $body
             }
         )
@@ -154,10 +151,58 @@ impl Declare {
         )
     }
 
+    fn impl_vnode(&self) -> TokenStream {
+        let elem_name = TokenTree::Literal(Literal::string(self.name.to_string().as_str()));
+        let mut req_children = TokenStream::new();
+        for (child_name, _, _) in self.req_children() {
+            req_children.extend(quote!(
+                children.push(self.$child_name.vnode());
+            ));
+        }
+        let mut opt_children = TokenStream::new();
+        if self.opt_children.is_some() {
+            opt_children.extend(quote!(for child in &self.children {
+                children.push(child.vnode());
+            }));
+        }
+
+        let mut push_attrs = TokenStream::new();
+        for (attr_name, _, attr_str) in self.attrs() {
+            push_attrs.extend(quote!(
+                if let Some(ref value) = self.attrs.$attr_name {
+                    attributes.push(($attr_str.to_string(), value.to_string()));
+                }
+            ));
+        }
+
+        quote!(
+            let mut attributes = Vec::new();
+            $push_attrs
+            for (key, value) in &self.data_attributes {
+                attributes.push((format!("data-{}", key), value.to_string()));
+            }
+
+            let mut children = Vec::new();
+            $req_children
+            $opt_children
+
+            ::elements::VNode::Element(::elements::VElement {
+                name: $elem_name,
+                attributes,
+                children
+            })
+        )
+    }
+
     fn impl_node(&self) -> TokenStream {
         let elem_name = self.elem_name();
+        let vnode = self.impl_vnode();
         quote!(
-            impl ::elements::Node for $elem_name {}
+            impl ::elements::Node for $elem_name {
+                fn vnode(&self) -> ::elements::VNode {
+                    $vnode
+                }
+            }
         )
     }
 
@@ -270,7 +315,7 @@ impl Declare {
         quote!(
             impl std::fmt::Display for $elem_name {
                 fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
-                    write!(f, "<{}", $name);
+                    write!(f, "<{}", $name)?;
                     $print_attrs
                     for (key, value) in &self.data_attributes {
                         write!(f, " data-{}={:?}", key, value)?;
diff --git a/typed-html/src/bin/main.rs b/typed-html/src/bin/main.rs
index de7cbb6..df52532 100644
--- a/typed-html/src/bin/main.rs
+++ b/typed-html/src/bin/main.rs
@@ -5,6 +5,7 @@
 extern crate typed_html;
 extern crate typed_html_macros;
 
+use typed_html::elements::Node;
 use typed_html::types::*;
 use typed_html_macros::html;
 
@@ -37,4 +38,5 @@ fn main() {
         </html>
     );
     println!("{}", doc.to_string());
+    println!("{:?}", doc.vnode());
 }
diff --git a/typed-html/src/elements.rs b/typed-html/src/elements.rs
index 7292991..47f4f3c 100644
--- a/typed-html/src/elements.rs
+++ b/typed-html/src/elements.rs
@@ -6,7 +6,22 @@ use typed_html_macros::declare_element;
 
 use super::types::*;
 
-pub trait Node: Display {}
+#[derive(Clone, Debug)]
+pub enum VNode {
+    Text(String),
+    Element(VElement),
+}
+
+#[derive(Clone, Debug)]
+pub struct VElement {
+    pub name: &'static str,
+    pub attributes: Vec<(String, String)>,
+    pub children: Vec<VNode>,
+}
+
+pub trait Node: Display {
+    fn vnode(&self) -> VNode;
+}
 
 pub trait Element: Node {
     fn name() -> &'static str;
@@ -61,7 +76,11 @@ impl Display for TextNode {
     }
 }
 
-impl Node for TextNode {}
+impl Node for TextNode {
+    fn vnode(&self) -> VNode {
+        VNode::Text(self.0.clone())
+    }
+}
 impl FlowContent for TextNode {}
 impl PhrasingContent for TextNode {}