import bpy


class ADDONNAME_PT_main_panel(bpy.types.Panel):

    bl_label = "Add Shader Panel"
    bl_idname = "ADDONNAME_PT_main_panel"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = 'New Tab'

    def draw(self, context):
        layout = self.layout
        layout.operator("addonname.addbasic_operator")



class ADDONNAME_OT_add_basic(bpy.types.Operator):
    bl_label = "Add Basic Shader"
    bl_idname = "addonname.addbasic_operator"


    col = bpy.props.FloatVectorProperty(name= "Color", subtype= 'COLOR_GAMMA' , size=4, default= (0,1,0,1))


    def execute(self, context):


        material_basic = bpy.data.materials.new(name= "Basic")
        material_basic.use_nodes = True

        principled_node = material_basic.node_tree.nodes.get('Principled BSDF')
        principled_node.inputs[7].default_value = 0.08

        rgb_node = material_basic.node_tree.nodes.new('ShaderNodeRGB')
        rgb_node.location = (-250, 0)
        rgb_node.outputs[0].default_value = self.col


        link = material_basic.node_tree.links.new
        link(rgb_node.outputs[0], principled_node.inputs[0])

        bpy.context.object.active_material = material_basic

        return {'FINISHED'}

    def invoke(self, context, event):
        return context.window_manager.invoke_props_dialog(self)




classes = [ADDONNAME_PT_main_panel, ADDONNAME_OT_add_basic]



def register():
    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)



if __name__ == "__main__":
    register()