support multiple files for drag-drop import

addons/blender_dds_addon/ui/drag_drop.py

@@ -1,3 +1,4 @@
+import os
 import time
 import traceback
 
@@ -18,27 +19,31 @@ class DDS_OT_drag_drop_import(bpy.types.Operator):
     """Operator to import dropped .dds files."""
     bl_idname = "dds.drag_drop_import"
     bl_label = "Import a dropped dds file"
-    filepath: bpy.props.StringProperty(subtype='FILE_PATH', options={'SKIP_SAVE'})
+    directory: bpy.props.StringProperty(subtype='FILE_PATH', options={'SKIP_SAVE'})
+    files: bpy.props.CollectionProperty(type=bpy.types.OperatorFileListElement, options={'SKIP_SAVE'})
 
     @classmethod
     def poll(cls, context):
         return is_dds_panel(context)
 
     def execute(self, context):
         """ Calls to this Operator can set unfiltered filepaths, ensure the file extension is .txt. """
-        if not self.filepath or not self.filepath.endswith(".dds"):
+        if not self.directory or not self.files:
             return {'CANCELLED'}
 
         texconv = Texconv()
         astcenc = Astcenc()
 
         try:
             start_time = time.time()
-
-            import_dds(context, self.filepath,
-                       texconv=texconv, astcenc=astcenc)
-            flush_stdout()
-            count = 1
+            count = 0
+
+            for file in self.files:
+                filepath = os.path.join(self.directory, file.name)
+                import_dds(context, filepath,
+                           texconv=texconv, astcenc=astcenc)
+                flush_stdout()
+                count += 1
             elapsed_s = f'{(time.time() - start_time):.2f}s'
             if count == 0:
                 raise RuntimeError("Imported no DDS files.")
@@ -62,7 +67,7 @@ def execute(self, context):
         return ret
 
     def invoke(self, context, event):
-        if self.filepath:
+        if self.directory and self.files:
             return self.execute(context)
         context.window_manager.fileselect_add(self)
         return {'RUNNING_MODAL'}