Add support for directory creation and binary files

- Use the `Path` module instead of `os`
- Add ability to create any amount of missing directories for a given file
- Add ability to save both text and binary files to save images (or other file types) later

gpt_engineer/db.py

@@ -1,35 +1,52 @@
 from dataclasses import dataclass
-import os
 from pathlib import Path
 
-
+# This class represents a simple database that stores its data as files in a directory.
+# It supports both text and binary files, and can handle directory structures.
 class DB:
-    """A simple key-value store, where keys are filenames and values are file contents."""
-
     def __init__(self, path):
+        # Convert the path string to a Path object and get its absolute path.
         self.path = Path(path).absolute()
-        os.makedirs(self.path, exist_ok=True)
+
+        # Create the directory if it doesn't exist.
+        self.path.mkdir(parents=True, exist_ok=True)
 
     def __getitem__(self, key):
-        with open(self.path / key, encoding='utf-8') as f:
-            return f.read()
+        # Combine the database directory with the provided file path.
+        full_path = self.path / key
+
+        # Check if the file exists before trying to open it.
+        if full_path.is_file():
+            # Open the file in text mode and return its content.
+            with full_path.open('r') as f:
+                return f.read()
+        else:
+            # If the file doesn't exist, raise an error.
+            raise FileNotFoundError(f"No such file: '{full_path}'")
 
     def __setitem__(self, key, val):
-        Path(self.path / key).absolute().parent.mkdir(parents=True, exist_ok=True)
+        # Combine the database directory with the provided file path.
+        full_path = self.path / key
 
-        with open(self.path / key, 'w', encoding='utf-8') as f:
-            f.write(val)
+        # Create the directory tree if it doesn't exist.
+        full_path.parent.mkdir(parents=True, exist_ok=True)
 
-    def __contains__(self, key):
-        return (self.path / key).exists()
+        # Write the data to the file. If val is a string, it's written as text.
+        # If val is bytes, it's written as binary data.
+        if isinstance(val, str):
+            full_path.write_text(val)
+        elif isinstance(val, bytes):
+            full_path.write_bytes(val)
+        else:
+            # If val is neither a string nor bytes, raise an error.
+            raise TypeError("val must be either a str or bytes")
 
 
+# dataclass for all dbs:
 @dataclass
 class DBs:
-    """A dataclass for all dbs"""
-
     memory: DB
     logs: DB
     identity: DB
     input: DB
-    workspace: DB
+    workspace: DB