import bpy

def popup_error(message: str):
    def _draw(self, context):
        self.layout.label(text=message)
    try:
        bpy.context.window_manager.popup_menu(_draw, title="HardHat", icon='ERROR')
    except Exception:
        print(f"ERROR: {message}")


def selected_hair_meshes():
    names = (bpy.context.scene.get('HH_HairTargets') or '').split(';')
    names = [n for n in names if n]
    if names:
        objs = [bpy.data.objects.get(n) for n in names]
        return [o for o in objs if o and o.type == 'MESH']
    popup_error("No HardHat hair targets set. Click 'Set HardHat Hair Targets' first.")
    return []


def ensure_basis(obj):
    if not obj.data.shape_keys:
        obj.shape_key_add(name='Basis', from_mix=False)


def ensure_hardhat_key(obj):
    # Ensure Basis
    ensure_basis(obj)
    # Find or create HardHat shapekey
    key = obj.data.shape_keys.key_blocks.get('HardHat')
    if not key:
        key = obj.shape_key_add(name='HardHat', from_mix=False)
    key.value = 0.0
    return key


def run():
    hair_objs = selected_hair_meshes()
    if not hair_objs:
        print("Error: Select hair mesh object(s) before running")
        return

    for obj in hair_objs:
        ensure_hardhat_key(obj)
        print(f"Ensured 'HardHat' shapekey on '{obj.name}' (value=0.0)")

    print("hh_shapekey: Done.")


run()