import bpy
from mathutils import Vector

def create_settings_bone():
    """
    Creates a new bone under the armature, parents it to the 'root' bone,
    and sets the bone colors to Theme Color Set 11.
    """
    # Get the active object (should be an armature)
    armature_obj = bpy.context.active_object
    
    if not armature_obj or armature_obj.type != 'ARMATURE':
        print("Error: Please select an armature object")
        return
    
    # Enter Edit Mode
    bpy.context.view_layer.objects.active = armature_obj
    bpy.ops.object.mode_set(mode='EDIT')
    
    armature = armature_obj.data
    
    # Find the 'root' bone
    root_bone = None
    for bone in armature.edit_bones:
        if bone.name.lower() == 'root':
            root_bone = bone
            break
    
    if not root_bone:
        print("Error: 'root' bone not found in armature")
        bpy.ops.object.mode_set(mode='OBJECT')
        return
    
    # Find the root bone collection
    root_collection = None
    for collection in armature.collections:
        if collection.name.lower() == 'root':
            root_collection = collection
            break
    
    # Create a new bone named 'Settings'
    new_bone = armature.edit_bones.new('Settings')
    
    # Position the new bone at y = 0.5
    new_bone.head = Vector((0, 0.5, 0))
    new_bone.tail = Vector((0, 0.5, 0.5))
    
    # Parent the new bone to the root bone
    new_bone.parent = root_bone
    
    # Switch to Object Mode to add bone to collection
    bpy.ops.object.mode_set(mode='OBJECT')
    
    # Add the new bone to the root collection
    if root_collection:
        # Get the bone data
        bone_data = armature.bones['Settings']
        # Add to root collection
        root_collection.assign(bone_data)
        print("Settings added to Root bone collection")
    
    # Switch to Pose Mode to set bone colors
    bpy.ops.object.mode_set(mode='POSE')
    
    # Get the pose bone
    pose_bone = armature_obj.pose.bones['Settings']
    
    # Set bone color to Theme Color Set 11
    pose_bone.color.palette = 'THEME11'
    
    # Set bone color custom (for viewport display)
    pose_bone.bone.color.palette = 'THEME11'
    
    # Return to Object Mode
    bpy.ops.object.mode_set(mode='OBJECT')
    
    # Go into Pose Mode and select Settings bone
    bpy.ops.object.mode_set(mode='POSE')
    
    # Deselect all bones first
    bpy.ops.pose.select_all(action='DESELECT')
    
    # Select the Settings bone (compatible with Blender 4.2/4.5 LTS and 5.0+)
    pose_bone = armature_obj.pose.bones['Settings']
    
    # Blender 5.0+ uses pose_bone.select, older versions use pose_bone.bone.select
    if hasattr(pose_bone, 'select'):
        # Blender 5.0+
        pose_bone.select = True
    elif hasattr(pose_bone.bone, 'select'):
        # Blender 4.2 LTS, 4.5 LTS
    pose_bone.bone.select = True
    
    armature_obj.data.bones.active = pose_bone.bone
    
    # Create widget for the Settings bone
    bpy.ops.bonewidget.create_widget()
    
    # Set the custom shape wire width to 1
    armature_obj.pose.bones['Settings'].custom_shape_wire_width = 1
    
    # Return to Object Mode
    bpy.ops.object.mode_set(mode='OBJECT')
    
    print("Settings created successfully and parented to root bone")
    print("Bone colors set to Theme Color Set 11")
    print("Widget created for Settings bone")

create_settings_bone()