588. Design In-Memory File System

solution.py

from collections import deque

class FileObject:
    def __init__(self, name):
        self.content = None
        self.name = name
        self.children = []
        
        
class FileSystem:

    def __init__(self):
        # initalize empty directory, aka root directory
        self.root = FileObject("",)
        
    def get_path(self, path):
        path_list = path.split("/")
        
        if not path_list:
            return []
        
        return path_list[1:]
        

    def ls(self, path: str) -> List[str]:
        path_list = self.get_path(path)
        
        if not path_list:
            return []
        
        current_node = self.root
        
        for p in path_list:
            for child in current_node.children:
                if child.name == p:
                    current_node = child
                    break
        
        return [current_node.name]  if current_node.content else sorted([x.name for x in current_node.children]) 
            
          
    
    def get_object(self, path:str) -> FileObject:
        path_list = self.get_path(path)
        
        if not path_list:
            return []
        
        current_node = self.root
        
        for p in path_list:
            if p not in [x.name for x in current_node.children]:
                new_directory = FileObject(name=p)
                current_node.children.append(
                    new_directory
                )      
                current_node = new_directory
            else:
                current_node = next(filter(lambda x: x.name == p, current_node.children), None)
                
        return current_node
        
            

    def mkdir(self, path: str) -> None:
        self.get_object(path)
                

    def addContentToFile(self, filePath: str, content: str) -> None:
        obj = self.get_object(filePath)

        if obj.content:
            obj.content += content
        else:
            obj.content = content

    def readContentFromFile(self, filePath: str) -> str:
        return self.get_object(filePath).content