Create draft_utils.py

Author: CodeIter

src/draft_utils.py

@@ -0,0 +1,46 @@
+import os
+import json
+
+def ensure_drafts_file(drafts_file: str) -> str:
+    """
+    Ensure the drafts file exists following these rules:
+
+    - If the provided drafts_file does not exist and it is a simple filename (i.e., it does not contain
+      any path separator), then use the XDG Base Directory Specification to determine a cache directory:
+        * It checks for the XDG_CACHE_HOME environment variable.
+        * If not set, defaults to HOME/.cache.
+      Then, a sub-folder named "threads-cli" is created within that cache directory, and
+      drafts_file is placed inside that sub-folder.
+      
+    - If drafts_file is a simple filename, but a file does not exist at that location, or if it is given as a full 
+      path, the application uses that path exactly as given.
+      
+    - If the drafts file does not exist, create an empty JSON file (with an empty dict as content by default).
+
+    Returns:
+        The final path to the drafts file.
+    
+    Raises:
+        EnvironmentError: If the required HOME environment variable is not set when needed.
+    """
+    # Check if drafts_file doesn't exist and is a simple filename (without path separator).
+    if not os.path.exists(drafts_file) and os.path.sep not in drafts_file:
+        # Determine the cache directory using XDG_CACHE_HOME if available,
+        # otherwise default to HOME/.cache.
+        xdg_cache_home = os.getenv('XDG_CACHE_HOME')
+        if not xdg_cache_home:
+            home = os.getenv('HOME')
+            if not home:
+                raise EnvironmentError("HOME environment variable is not set.")
+            xdg_cache_home = os.path.join(home, '.cache')
+        # Define the final path: XDG_CACHE_HOME/threads-cli/drafts_file
+        drafts_dir = os.path.join(xdg_cache_home, "threads-cli")
+        os.makedirs(drafts_dir, exist_ok=True)
+        drafts_file = os.path.join(drafts_dir, drafts_file)
+
+    # If the drafts file still does not exist, create an empty JSON file.
+    if not os.path.exists(drafts_file):
+        with open(drafts_file, "w") as f:
+            json.dump({}, f)
+    
+    return drafts_file