# SPDX-License-Identifier: Apache-2.0
# Copyright 2018-2021 The glTF-Blender-IO authors.

import os
import sys
from pathlib import Path
import bpy

from ...io.com.gltf2_io_debug import print_console


def dll_path() -> Path:
    """
    Get the DLL path depending on the underlying platform.
    :return: DLL path.
    """
    lib_name = 'extern_draco'
    blender_root = Path(bpy.app.binary_path).parent
    python_lib = Path('{v[0]}.{v[1]}/python/lib'.format(v=bpy.app.version))
    python_version = 'python{v[0]}.{v[1]}'.format(v=sys.version_info)

    path = os.environ.get('BLENDER_EXTERN_DRACO_LIBRARY_PATH')
    if path is None:
        path = {
            'win32': blender_root / python_lib / 'site-packages',
            'linux': blender_root / python_lib / python_version / 'site-packages',
            'darwin': blender_root.parent / 'Resources' / python_lib / python_version / 'site-packages'
        }.get(sys.platform)
    else:
        return Path(path)

    library_name = {
        'win32': '{}.dll'.format(lib_name),
        'linux': 'lib{}.so'.format(lib_name),
        'darwin': 'lib{}.dylib'.format(lib_name)
    }.get(sys.platform)

    if path is None or library_name is None:
        print_console('WARNING', 'Unsupported platform {}, Draco mesh compression is unavailable'.format(sys.platform))

    return path / library_name


def dll_exists(quiet=False) -> bool:
    """
    Checks whether the DLL path exists.
    :return: True if the DLL exists.
    """
    path = dll_path()
    exists = path.exists() and path.is_file()
    if quiet is False:
        if exists:
            print_console('INFO', 'Draco mesh compression is available, use library at %s' % dll_path().absolute())
        else:
            print_console('ERROR', 'Draco mesh compression is not available because library could not be found at %s' % dll_path().absolute())
    return exists
