bin-tree-pseudo-code-experiment

fn buildPathString(node) {
	var path = ''

	currentNode = node
	while (currentNode.parent) {

		if (currentNode.parent.left === currentNode) {
			// the current node was to the left of its parent, meaning a "."
			path = '.' + path
		} else {
			// the current node was to the right of its parent, meaning a "-"
			path = '-' + path
		}

		// Assuming that "rootNode.parent" would be null,
		// which would stop this while loop
		currentNode = currentNode.parent
	}

	return path
}

fn considerNode(string letter, Node node) {
	
	if (node.value === letter) {
		// bingo, found our letter, so the path leading to the current node is what we're looking for.
		return buildPathString(node)
	}

	// The current node is not the letter we're looking for.
	// Let's look in the left first ("dot" path)
	if (node.left) {
		// explore the node if it's available
		var response = considerNode(letter, node.left)
		if (response) {
			// Got a match
			return response
		}
	}

	// Looking in the right node ("dash" path)
	if (node.right) {
		// explore the node if it's available
		var response = considerNode(letter, node.right)
		if (response) {
			// Got a match
			return response
		}
	}

	// could not find our letter in either the left- or right node.
	return null

}


fn encode_letter(Tree tree, string letter) {
	
	var path = considerNode(letter, tree.rootNode)

	if (path) {
		// The letter was found. The response is a string representing the path, so something like: "--."
		return path
	} else {
		throw new Error('could not find the given letter')
	}

}