README.md

Root and Nodes library

This is a framework for implementing a tree-like structure in C#. It consists of two main classes: Root and Node.

Root

The Root class represents the root of the tree. It has the following responsibilities:

• Keeping a list of nodes that are owned by the root.
• Keeping track of the currently active node.
• Setting the start node for the tree.
• Running the tree by setting the active node to the start node and calling the Entry method on the start node.
• Passing input to the OnKeyboard method of the active node.
• Setting the active node to the next node in the tree, as determined by the output of the current node.

Node

The Node class represents a node in the tree. It has the following responsibilities:

• Being able to connect to a child node.
• Keeping a list of possible outputs.
• Returning the child node corresponding to a given output.
• Implementing an OnEntry method that is called when the node is entered.
• Implementing an OnKeyboard method that is called when input is received.

Usage

To use the framework, you will need to create your own classes that inherit from Root and Node and implement their abstract methods. You can then create an instance of your Root class and use the SetStartNode and Run methods to start the tree. Input can be passed to the Root instance using the OnKeyboard method.

Root and Nodes Console Example

This is a console application demonstrating the usage of the RootAndNodesPattern library. The application displays a message, asks the user a question, and based on their answer, either prints a series of asterisks or displays another message. The user can then exit the application by pressing any key.

See full implementation in Root-Nodes-Workflow-Pattern/RootAndNodesPattern/RootAndNodesConsoleExample directory. Here you can only see a snippet of the main code:

class Program
{
	static void Main(string[] args)
	{
		Console.WriteLine("OGNIA...");

		var root = new ExampleTree("teo");
		Node showMessage = new MessageNode(root, "Welcome", "This is start node...");
		Node asterisks = new AsteriskPrinterkNode(root, "Asterisks", 50);
		Node question = new YesOrNoMenuNode(root, "Question about asterisk", "Do you want to write asterisks?");
		Node notAsterisksMessage = new MessageNode(root, "Not asterisk", "You didn't want to asterisks.");
		Node wrongChoiceMessage = new MessageNode(root, "Bad choice.", "Bad choice. Try once again.");
		Node endMessage = new MessageNode(root, "End", "Fine.");

		showMessage.JoinChildNode(question);
		question.JoinChildNode(YesOrNoMenuNode.YES_OUTPUT, asterisks);
		question.JoinChildNode(YesOrNoMenuNode.NO_OUTPUT, notAsterisksMessage);
		question.JoinChildNode(wrongChoiceMessage);
		wrongChoiceMessage.JoinChildNode(question);
		asterisks.JoinChildNode(endMessage);
		notAsterisksMessage.JoinChildNode(endMessage);

		root.SetStartNode(showMessage);
		root.Run();

		while (true)
			root.OnKeyboard(Console.ReadKey().KeyChar);
	}
}