#!/usr/bin/env python3
import pathlib
import sys

import bpy


def set_socket(node, name, value):
    socket = node.inputs.get(name)
    if socket is not None:
        socket.default_value = value


def main(output: pathlib.Path) -> None:
    bpy.ops.wm.read_factory_settings(use_empty=True)
    material = bpy.data.materials.new("WebGapMaterial")
    material.use_nodes = True
    material.diffuse_color = (0.2, 0.4, 0.8, 0.9)
    nodes = material.node_tree.nodes
    links = material.node_tree.links
    principled = nodes.get("Principled BSDF")
    output_node = nodes.get("Material Output")
    if principled is None or output_node is None:
        raise RuntimeError("default Principled/Output nodes are missing")
    set_socket(principled, "Base Color", (0.2, 0.4, 0.8, 0.9))
    set_socket(principled, "Metallic", 0.35)
    set_socket(principled, "Roughness", 0.6)
    set_socket(principled, "IOR", 1.6)
    set_socket(principled, "Specular IOR Level", 0.35)
    set_socket(principled, "Transmission Weight", 0.27)
    set_socket(principled, "Coat Weight", 0.64)
    set_socket(principled, "Coat Roughness", 0.12)
    set_socket(principled, "Emission Color", (0.05, 0.1, 0.2, 1.0))
    set_socket(principled, "Emission Strength", 3.5)
    set_socket(principled, "Alpha", 0.9)
    if not any(link.from_node == principled and link.to_node == output_node for link in links):
        links.new(principled.outputs["BSDF"], output_node.inputs["Surface"])
    mesh = bpy.data.meshes.new("WebGapMaterialMesh")
    mesh.from_pydata([(-1.0, -1.0, 0.0), (1.0, -1.0, 0.0), (0.0, 1.0, 0.0)], [], [(0, 1, 2)])
    mesh.materials.append(material)
    obj = bpy.data.objects.new("WebGapMaterialObject", mesh)
    bpy.context.collection.objects.link(obj)
    bpy.ops.wm.save_as_mainfile(filepath=str(output.resolve()), check_existing=False, compress=True)


if __name__ == "__main__":
    arguments = sys.argv[sys.argv.index("--") + 1 :]
    if len(arguments) != 1:
        raise SystemExit("usage: blender -b --python M16-GAP-00013.py -- OUTPUT")
    main(pathlib.Path(arguments[0]))