(FEAT): Working on node implementation.

The inline and structure nodes have some basic implementations. The
parser needs to begin next.

flake.nix

@@ -11,7 +11,7 @@
       let
         pkgs = import nixpkgs { inherit system; };
       in
-      {
+        {
         # Define the development shell.
         # When you run `nix develop` (or direnv activates), you'll enter this shell.
         devShells.default = pkgs.mkShell {
@@ -35,7 +35,7 @@
             # Exec zsh to replace the current shell process with zsh.
             # This ensures your prompt and zsh configurations load correctly.
             exec zsh
-          '';
+            '';
         };
       }
     );

lib/inlindeNode.h

@@ -1,17 +0,0 @@
-#ifndef INLINENODE_H
-#define INLINENODE_H
-#include "node.h"
-
-class InlineNode : public Node{
-    public:
-        InlineNode(std::string content) : content(content);
-    protected:
-        std::string content;
-};
-
-class TextNode : public InlineNode{};
-class BoldNode : public InlineNode{};
-class Italic : public InlineNode{};
-class BoldItalic : public InlineNode{};
-
-#endif 

lib/inlineNode.cpp

@@ -0,0 +1,23 @@
+#include "inlineNode.h"
+
+#include <memory>
+#include <stdexcept>
+#include <string>
+
+using std::string;
+
+void InlineNode::AddChild(std::unique_ptr<Node> child) {
+  throw std::runtime_error("Cannot add a child to an InlineNode.");
+}
+
+string TextNode::ToHtml() const { return this->content; }
+
+string ItalicNode::ToHtml() const { return "<em>" + this->content + "</em>"; }
+
+string BoldNode::ToHtml() const {
+  return "<strong>" + this->content + "</strong>";
+}
+
+string BoldItalicNode::ToHtml() const {
+  return "<strong><em>" + this->content + "</em></strong>";
+}

lib/inlineNode.h

@@ -0,0 +1,97 @@
+#ifndef INLINENODE_H
+#define INLINENODE_H
+
+#include "node.h"
+#include <vector>
+
+/**
+ * @desc ABC inline node for textual nodes.
+ *
+ * An inline node has content, but no children. An attempt to add children to
+ * this node will result in a runtime exception.
+ * Inline nodes define text itself, not textual tags, but the actual text inside
+ * the tags.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class InlineNode : public Node {
+public:
+  InlineNode(std::string content) : content(content) {};
+
+  /**
+   * @brief Return node as HTML string.
+   *
+   * This method is virtual and required to be overridden.
+   *
+   * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+   */
+  virtual std::string ToHtml() const = 0;
+
+  /**
+   * @brief Cannot add a child to this class.
+   *
+   * This method simply returns a runtime error, since there is no reason to add
+   * a child to a textual node.
+   *
+   * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+   */
+  void AddChild(std::unique_ptr<Node> child);
+
+protected:
+  std::string content;
+};
+
+/**
+ * @desc A raw textual node.
+ *
+ * This node is simple, it simple returns it's content with no formatting.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class TextNode : public InlineNode {
+public:
+  TextNode(std::string content) : InlineNode(content) {};
+  std::string ToHtml() const;
+};
+
+/**
+ * @desc A italic textual node.
+ *
+ * This node returns it's content wrapped with <em></em> tags.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class ItalicNode : public InlineNode {
+public:
+  ItalicNode(std::string content) : InlineNode(content) {};
+  std::string ToHtml() const;
+};
+
+/**
+ * @desc A bold textual node.
+ *
+ * This node returns it's content wrapped with <strong></strong> tags.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class BoldNode : public InlineNode {
+public:
+  BoldNode(std::string content) : InlineNode(content) {};
+  std::string ToHtml() const;
+};
+
+/**
+ * @desc A bold and italic textual node.
+ *
+ * This node returns it's content wrapped with <strong></strong> AND <em>/<em>
+ * tags.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class BoldItalicNode : public InlineNode {
+public:
+  BoldItalicNode(std::string content) : InlineNode(content) {};
+  std::string ToHtml() const;
+};
+
+#endif

lib/node.h

@@ -16,6 +16,7 @@
 /// method is required. When calling a function that accepts a reference, the
 /// reference operator (*) works perfectly fine. Hence, in this project we will
 /// try to avoid using raw pointers, and only use references when needed.
+/// Reference: https://www.youtube.com/watch?v=AmjoK55h68Y&t=166s
 
 // NOTE ABC
 class Node {

lib/structureNode.cpp

@@ -1 +1,65 @@
 #include "structureNode.h"
+#include <cstdio>
+#include <sstream>
+#include <stdexcept>
+#include <string>
+
+using std::string;
+
+string DocumentNode::ToHtml() const {
+  std::stringstream ss;
+  ss << "<!DOCTYPE html>\n\t<html lang=\"en\">\n\t\t<head>\n\t\t\t<meta "
+        "charset=\"UTF-8\">\n\t\t\t<meta "
+        "name=\"viewport\" content=\"width=device-width, "
+        "initial-scale=1.0\">\n\t\t\t<title>Document</title>\n\t\t</"
+        "head>\n\t<body>\n";
+
+  for (const auto &child : this->GetChilren()) {
+    ss << child->ToHtml();
+  }
+
+  ss << "\n\t</body>\n</html>";
+  return ss.str();
+}
+
+HeadingNode::HeadingNode(int size) {
+  if (1 <= size && size <= 6) {
+    this->size = size;
+    return;
+  }
+
+  throw std::runtime_error("HeadingNode.size must be between 1 and 6.");
+}
+
+string HeadingNode::ToHtml() const {
+  std::stringstream ss;
+  ss << "<h" << size << ">";
+
+  for (const auto &child : this->GetChilren()) {
+    ss << child->ToHtml();
+  }
+
+  ss << "</h" << size << ">\n";
+  return ss.str();
+}
+
+string ParagraphNode::ToHtml() const {
+  std::stringstream ss;
+  ss << "<p>";
+
+  for (const auto &child : this->GetChilren()) {
+    ss << child->ToHtml();
+  }
+
+  ss << "</p>\n";
+  return ss.str();
+}
+
+// TODO: Implement
+string ListNode::ToHtml() const {
+  std::stringstream ss;
+  ss << (this->ordered ? "<ol>NOT YET IMPLEMENTED</ol>"
+                       : "<ul>NOT YET IMPLEMENTED</ul>");
+
+  return ss.str();
+}

lib/structureNode.h

@@ -2,12 +2,103 @@
 #define STRUCTURENODE_H
 
 #include "node.h"
+#include <string>
 
-class StructureNode : public Node {};
+/**
+ * @desc ABC inline node for structure nodes.
+ *
+ * A structure node has no content, but instead it has children which contain
+ * content. These children can be other structure nodes, or they can be inline
+ * nodes. Inline nodes allow this node to display textual content.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class StructureNode : public Node {
+public:
+  /**
+   * @brief Return node as HTML string.
+   *
+   * This method is virtual and required to be overridden.
+   *
+   * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+   */
+  virtual std::string ToHtml() const = 0;
+};
 
-class ListNode : public StructureNode {};
+/**
-class HeadingNode : public StructureNode {};
+ * @desc A main HTML document node.
-class DocumentNode : public StructureNode {};
+ *
-class ParagraphNode : public StructureNode {};
+ * This node should be used as the root of the DOM. Calling `ToHtml` will yield
+ * an HTML document boiler plate with it's children rendered as the body.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class DocumentNode : public StructureNode {
+public:
+  std::string ToHtml() const;
+};
+
+/**
+ * @desc A heading node.
+ *
+ * A heading contains children that are expected to be inline nodes. These
+ * children represent the textual content of the node. This heading node simply
+ * stores the children and the size of the heading. A size of 1 means <h1>, etc.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class HeadingNode : public StructureNode {
+protected:
+  /**
+   * @brief Size of the heading.
+   *
+   * The constructor will enforce size requirements.
+   *
+   * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+   */
+  int size;
+
+public:
+  HeadingNode(int size);
+  std::string ToHtml() const;
+};
+
+/**
+ * @desc A paragraph node.
+ *
+ * A paragraph contains children that are expected to be inline nodes. These
+ * children represent the textual content of the node. This heading node simply
+ * stores the children.
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class ParagraphNode : public StructureNode {
+public:
+  std::string ToHtml() const;
+};
+
+/**
+ * @desc A list container node.
+ *
+ * This node is used to wrap list elements. Not to be confused with the list
+ * elements themselves. This is the parent (<ul> or <ol>), and must be created
+ * with a boolean which defines whether the list should be ordered or not.
+ * i.e., should have numbers (use the <ol> tags).
+ *
+ * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+ */
+class ListNode : public StructureNode {
+protected:
+  /**
+   * @brief Should the list be ordered (numeric).
+   *
+   * @author Hayden Hargreaves (hhargreaves2006@gmail.com)
+   */
+  bool ordered;
+
+public:
+  ListNode(bool ordered = false) : ordered(ordered) {};
+  std::string ToHtml() const;
+};
 
 #endif

src/main.cpp

@@ -1,4 +1,8 @@
+#include "../lib/inlineNode.h"
 #include "../lib/parser.h"
+#include "../lib/structureNode.h"
+
+#include <memory>
 #include <stdexcept>
 
 int main(int argc, char **argv) {
@@ -23,5 +27,29 @@ int main(int argc, char **argv) {
 
   std::cout << std::endl;
 
+  DocumentNode root;
+  std::unique_ptr<TextNode> node = std::make_unique<TextNode>("text node");
+  std::unique_ptr<BoldNode> bold = std::make_unique<BoldNode>("bold node");
+  std::unique_ptr<ItalicNode> italic =
+      std::make_unique<ItalicNode>("italic node");
+  std::unique_ptr<BoldItalicNode> bolditalic =
+      std::make_unique<BoldItalicNode>("bold italic node");
+
+  std::unique_ptr<HeadingNode> heading = std::make_unique<HeadingNode>(2);
+  heading->AddChild(std::move(node));
+  heading->AddChild(std::move(bold));
+
+  std::unique_ptr<ParagraphNode> para = std::make_unique<ParagraphNode>();
+  para->AddChild(std::move(italic));
+  para->AddChild(std::move(bolditalic));
+
+  std::unique_ptr<ListNode> list = std::make_unique<ListNode>();
+
+  root.AddChild(std::move(heading));
+  root.AddChild(std::move(para));
+  root.AddChild(std::move(list));
+
+  std::cout << root.ToHtml() << std::endl;
+
   return 0;
 }