From 2e999889bdc86d6aa41ad485215e45b59b8fabb1 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Fri, 4 Jun 2021 19:03:07 -0400
Subject: [PATCH] Attempts to implement tree construction.

---
 Machines/Utility/ROMCatalogue.cpp | 23 +++++++++++++++++++----
 Machines/Utility/ROMCatalogue.hpp |  2 ++
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/Machines/Utility/ROMCatalogue.cpp b/Machines/Utility/ROMCatalogue.cpp
index e38a8d4f9..8c8de8349 100644
--- a/Machines/Utility/ROMCatalogue.cpp
+++ b/Machines/Utility/ROMCatalogue.cpp
@@ -18,14 +18,29 @@ Request::Request(Name name, bool optional) {
 	node.is_optional = optional;
 }
 
+Request Request::append(Node::Type type, const Request &rhs) {
+	// Start with the easiest case: this is already an ::All request, and
+	// so is the new thing.
+	if(node.type == type && rhs.node.type == type) {
+		Request new_request = *this;
+		new_request.node.children.insert(new_request.node.children.end(), rhs.node.children.begin(), rhs.node.children.end());
+		return new_request;
+	}
+
+	// Otherwise create a new parent node.
+	Request parent;
+	parent.node.type = type;
+	parent.node.children.push_back(this->node);
+	parent.node.children.push_back(rhs.node);
+	return parent;
+}
+
 Request Request::operator &&(const Request &rhs) {
-	(void)rhs;
-	return *this;
+	return append(Node::Type::All, rhs);
 }
 
 Request Request::operator ||(const Request &rhs) {
-	(void)rhs;
-	return *this;
+	return append(Node::Type::Any, rhs);
 }
 
 bool Request::validate(Map &map) const {
diff --git a/Machines/Utility/ROMCatalogue.hpp b/Machines/Utility/ROMCatalogue.hpp
index ec69124c7..846095b19 100644
--- a/Machines/Utility/ROMCatalogue.hpp
+++ b/Machines/Utility/ROMCatalogue.hpp
@@ -179,6 +179,8 @@ struct Request {
 			bool validate(Map &) const;
 		};
 		Node node;
+
+		Request append(Node::Type type, const Request &rhs);
 };
 
 }