From 862cafb653cfaada29a741c89daa7d3509042714 Mon Sep 17 00:00:00 2001
From: viclpk <victor.kusumota@hotmail.com>
Date: Tue, 21 Jan 2025 20:25:56 -0300
Subject: [PATCH] Implement Node and NodeManager classes

The Node class represents a node with an 'id' and 'parent', ensuring valid values through type hints and validation. It includes methods for initialization, string representation, and equality comparison.

The NodeManager class manages a list of Node objects, with methods for retrieving, adding, and removing nodes. It includes a cascade removal feature, which ensures that nodes and their children are properly removed from the list. The class also validates that the input is a list of Node instances and prevents mutations to the original list.
---
 nodes/manager.py | 54 ++++++++++++++++++++++++++++++++++++++++++++++--
 nodes/node.py    | 25 +++++++++++++++++++---
 2 files changed, 74 insertions(+), 5 deletions(-)

diff --git a/nodes/manager.py b/nodes/manager.py
index b3c1178..cccbf44 100644
--- a/nodes/manager.py
+++ b/nodes/manager.py
@@ -1,5 +1,55 @@
-# Create here the NodeManager Class
+from typing import List
+import copy
+import sys
+import os
 
+sys.path.append(os.path.dirname(os.path.abspath(__file__)))
+from nodes.node import Node
 
 class NodeManager:
-    pass
+    nodes: List[Node]   # Adding the type hint for the 'nodes' attribute
+    
+    # Initializes the NodeManager with a list of Node objects.
+    # Ensures that the input is a list of Node instances.
+    def __init__(self, nodes: List[Node]):
+        if not isinstance(nodes, list):
+            raise ValueError("The nodes must be a list of Node objects.")
+
+        if not all(isinstance(node, Node) for node in nodes):
+            raise ValueError("The nodes must be a list of Node objects.")
+		
+        #This object must not mutate the received List
+        self.nodes: List[Node] = copy.deepcopy(nodes)
+		
+    # Returns the number of nodes in the NodeManager.
+    def __len__(self) -> int:
+        return len(self.nodes)
+    
+	# Retrieves a Node object by index from the nodes list.	
+    def __getitem__(self, index: int) -> Node:
+        return self.nodes[index]
+    
+	
+    # Removes a Node from the manager.
+    # Raises a ValueError if the node is not in the list of nodes.
+    def remove(self, node: Node) -> None:
+        if node not in self.nodes:
+            raise ValueError("The node does not exist in the nodes member.")
+            
+        self.nodes.remove(node)	
+        
+			
+    # Removes a Node and all its children (cascade removal).
+    # If the node has children, they are recursively removed as well.
+    def remove_cascade(self, node: Node) -> None:
+        #Check if the node exists in the list
+        if node not in self.nodes:
+            raise ValueError("The node does not exist in the nodes member.")
+			
+		# First remove the node itself
+        self.remove(node)
+        
+        # Cascade removal of nodes where the parent is the removed node
+        to_remove = [n for n in self.nodes if n.parent == node.id]
+        for child in to_remove:
+            self.remove_cascade(child)
\ No newline at end of file
diff --git a/nodes/node.py b/nodes/node.py
index 644ab4e..c380c23 100644
--- a/nodes/node.py
+++ b/nodes/node.py
@@ -1,5 +1,24 @@
-# Create here the Node Class
+class Node:
+    id: int  # Adding the type hint for the 'id' attribute
+    parent: int  # Adding the type hint for the 'parent' attribute
 
 
-class Node:
-    pass
+    # Initializes the Node with id and parent, ensuring valid values.
+    def __init__(self, id: int, parent: int):
+        if not isinstance(id, int) or not isinstance(parent, int):
+            raise ValueError("Both id and parent must be integers.")
+        if parent >= id:
+            raise ValueError("The parent cannot be greater than or equal to the id.")
+		
+        self.id: int = id
+        self.parent: int = parent
+		
+    # Returns a string representation of the Node.
+    def __repr__(self):
+        return f"Node({self.id}, {self.parent})"
+    
+    # Compares two Nodes based on id and parent.
+    def __eq__(self, other):
+        if isinstance(other, Node):
+            return self.id == other.id and self.parent == other.parent
+        return False
\ No newline at end of file