Moves all empty objects into collections named after them for easy importing into Blender's Asset Library

Blender KB3D Collection Maker.py

# Open your KB3D Pack. Make sure the textures are loaded and everything works as intended. This script assumes the Scene is named KB3D_"TitleCasePackName"-Native. It should be that by default.
# Create a new folder in your Asset Library Folder for Blender. (Edit>Preferences>FilePaths>AssetLibraries). I recommend a setup like this 
# (D:/BlenderAssetLibraries/KB3D/CyberDistricts/Cyberdistricts.blend)
# Where "CyberDistricts" would be the AssetLibrary.
# Open the script in Blender by going to the Text Editor and clicking "Open" to locate the file, or paste it from the Gist.
# Run the script by clicking the "Run Script" button in the Text Editor or pressing Alt+P.
# The script will create new collections for each type of asset in your scene and move the assets into these collections. It will also generate a unique ID for the asset pack and each asset in the pack.
# The script will then update the asset catalog file to include the new asset pack and each asset in the pack.
# Once the script is finished, you can save your Blender file and close it.
# You should now see it in the asset libraries section on Blender.
# Troubleshooting: If something goes wrong or a mistake is maid I have minimal errorchecking. Just undo before the script was run and delete the Catalogs or the "blender_assets.cats.txt" file, 
# they may trip up the script if it failed partway through.
# I put a lot of effort into making this, so if you'd like to show your appreciation-
#   you can donate to me through PayPal at the link below: https://paypal.me/mintyfresh

# Update: Remade better.
# TODO: Add simple GUI, test all packs, ensure consistent sizing and proper integration for easy placing of props.

import bpy
import os
from pathlib import Path
import uuid

#filename
file_name = str(bpy.data.scenes.keys()[0].split('_')[1].split('-')[0])
folder = Path(bpy.data.filepath).parent
new_uuid = str(uuid.uuid4())

# Mapping for collections to asset types
collection_map = {
    "Props": "Prop",
    "Buildings": "Bldg",
    "Structures": "Strc",
    "Vehicles": "Vehi",
    "Creatures": "Crea"
}
kit_catalog = {}

flipped_cmap = {v: k for k, v in collection_map.items()}

# Create the primary collections
primary_collections = ["Props", "Buildings", "Structures", "Vehicles", "Creatures", "Other"]
for collection_name in primary_collections:
    new_collection = bpy.data.collections.new(collection_name)
    bpy.context.scene.collection.children.link(new_collection)

# Loop through all the empties and sort them into the collections for the library
for obj in bpy.data.objects:
    if obj.type == "EMPTY" and obj.name.startswith("KB3D_"):

        # Sort the new collection into the correct group
        asset_type = obj.name.split("_")[2][:4]

        # Check if the asset_type exists in the flipped_cmap dictionary
        if asset_type in flipped_cmap:
            cm_col_name = flipped_cmap[asset_type]
        else:
            cm_col_name = "Other"

        # Create a new collection with Empty's name
        new_collection = bpy.data.collections.new(obj.name)
        bpy.data.collections[obj.name].objects.link(obj)

        # Linking Object groups
        cm_col = bpy.data.collections[cm_col_name]
        # Move the object's children to the new collection
        bpy.data.collections[cm_col.name].children.link(bpy.data.collections[obj.name])
        kit_catalog[obj.name] = cm_col.name
        
print(kit_catalog.values())

# Loop over Object and relink to parents.
for obj in bpy.data.objects:
    if obj.type == "MESH" and obj.parent != None:
        bpy.data.collections[obj.parent.name].objects.link(obj)
        
for empty in bpy.data.objects:
    if empty.type == 'EMPTY' and empty.name.startswith('KB3D_'):
        bpy.context.scene.collection.objects.unlink(empty)
        for child in empty.children:
            bpy.context.scene.collection.objects.unlink(child)

for col in bpy.data.collections:
    if col.name.startswith('KB3D_'):
        col.asset_mark()

# Create a list of all empty objects
empty_objects = [obj for obj in bpy.data.objects if obj.type == "EMPTY" and obj.name.startswith("KB3D_")]

# Loop through the list of empty objects and clear their locations
for obj in empty_objects:
    obj.location = (0, 0, 0)

asset_catalog_path = folder / "blender_assets.cats.txt"

# Initialize the list of lines and the asset_uuids dictionary
lines = []
asset_uuids = {}

# Read the existing asset catalog file into a list of lines
with asset_catalog_path.open('a+') as f:
    f.seek(0)  # Move the file pointer to the beginning of the file
    lines = f.readlines()

# Check if the blender_assets.cats.txt file is empty and initialize it if necessary
if os.path.getsize(asset_catalog_path) == 0:
    header_lines = [
        "# This is an Asset Catalog Definition file for Blender.\n",
        "#\n",
        "# Empty lines and lines starting with `#` will be ignored.\n",
        "# The first non-ignored line should be the version indicator.\n",
        "# Other lines are of the format \"UUID:catalog/path/for/assets:simple catalog name\"\n",
        "\n",
        "VERSION 1\n\n"
    ]
    lines.extend(header_lines)

# Add new lines to the catalog if necessary
file_contents = ''.join(lines)

# Initialize the asset_uuids dictionary outside the condition
collection_uuids = {collection_name: [] for collection_name in collection_map.keys()}
collection_uuids["Other"] = []

if file_name not in file_contents:
    if "KB3D" not in file_contents:
        lines.append(f"{str(uuid.uuid4())}:KB3D:KB3D\n")
    lines.append(f"{str(uuid.uuid4())}:KB3D/{file_name}:{file_name}\n")

    for collection_name in collection_map.keys():
        asset_uuid = str(uuid.uuid4())
        asset_uuids[collection_name] = asset_uuid
        lines.append(f"{asset_uuid}:KB3D/{file_name}/{collection_name}:{collection_name}\n")

    asset_uuid = str(uuid.uuid4())
    asset_uuids["Other"] = asset_uuid
    lines.append(f"{asset_uuid}:KB3D/{file_name}/Other:Other\n")

# Write the updated list of lines back to the file
with asset_catalog_path.open("w") as f:
    f.writelines(lines)

kit_catalog = {}

# Asset Library Adder
for col in bpy.data.collections:
    if col.name.startswith("KB3D_"):
        # Gets the asset type of an object from the Name
        # Ex: Bldg Prop Strc
        asset_type = col.name.split("_")[2][:4]  # e.g. "Bldg"

        # Check if the asset_type exists in the flipped_cmap dictionary
        if asset_type in flipped_cmap:
            asset_name = flipped_cmap[asset_type]  # e.g. "Buildings"
            col.asset_data.catalog_id = asset_uuids[asset_name]
        else:
            asset_name = "Other"
            col.asset_data.catalog_id = asset_uuids[asset_name]  # Set the catalog_id for the "Other" category

        print(col.name, asset_name)
        # Linking Object groups
        cm_col = bpy.data.collections[col.name]  # Buildings [Collection]
        print('adding', col.name, 'asset_data')

Could you try again @DomiTorfs?
I've gone ahead and remade the entire script to clean up the code, comment better, and finish concept ideas.

Just gotta find the kb3d asset file, delete any blender asset cat file if its in the same folder, then run the script.

If it cannot find the file you mentioned, it will now create one, but if one exists, it tends to have some trouble adjusting it.

Once its run with no errors, and is sorted in the asset library its ready to be tested. If it works, save the file and make sure the folder the blend file is in, is added to the Preferences>filepaths>asset libraries area so you can use it everywhere.

Getting :
Error: Python: Traceback (most recent call last):
File "D:\BlenderAssetLibraries\KB3D\Roads\KB3D_Roads-Native.blend\Blender KB3D Collection Maker.py", line 25, in
IndexError: list index out of range
I followed the instructions in the title , not sure what i'm doing wrong.
Any help would be appreciated, thanks.

@MeltedSynapse I don't have access to that Prop pack currently. Could you give me a screenshot of your outliner? I'm going to assume the file naming conventions are different in some packs.