import bpy
import os

def cleanup():
    # 删除所有meshes，这样我们可以从一个干净的环境开始
    bpy.ops.object.select_all(action='DESELECT')
    bpy.ops.object.select_by_type(type='MESH')
    bpy.ops.object.delete()

def add_thickness_to_stl(input_file_path, output_file_path, thickness=0.1):
    cleanup()

    # 激活STL导入插件
    bpy.ops.preferences.addon_enable(module="io_mesh_stl")
    
    # 导入STL
    bpy.ops.import_mesh.stl(filepath=input_file_path)

    # 确保导入的模型是当前活跃的
    obj = bpy.context.selected_objects[0]
    bpy.context.view_layer.objects.active = obj

    # 进入编辑模式
    bpy.ops.object.editmode_toggle()

    # 选择所有顶点
    bpy.ops.mesh.select_all(action='SELECT')

    # 使用Solidify修饰器来增加壁厚
    bpy.ops.object.modifier_add(type='SOLIDIFY')
    solidify = obj.modifiers["Solidify"]
    solidify.thickness = thickness

    # 应用修饰器
    bpy.ops.object.modifier_apply({"object": obj}, modifier="Solidify")

    # 返回对象模式
    bpy.ops.object.editmode_toggle()

    # 导出为STL
    bpy.ops.export_mesh.stl(filepath=output_file_path)

    cleanup()