using System;

using System.IO;

using System.Runtime.InteropServices;

namespace Python.Runtime.Codecs

{

partial class TestsRuntimeConfig

{

public static void Ensure()

{

if (Path.IsPathFullyQualified(Runtime.PythonDLL)) return;

string pyVer = Environment.GetEnvironmentVariable("PYTHON_VERSION");

if (!string.IsNullOrEmpty(pyVer))

{

Runtime.PythonVersion = Version.Parse(pyVer);

}

if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))

{

// work around Python.NET unstable issue with dll suffixes on *nix

if (!Runtime.PythonDLL.StartsWith("lib"))

{

string dllExtension = RuntimeInformation.IsOSPlatform(OSPlatform.OSX) ? ".dylib" : ".so";

Runtime.PythonDLL = "lib" + Runtime.PythonDLL + dllExtension;

}

}

else

{

Runtime.PythonDLL += ".dll";

}

string pyHome = Environment.GetEnvironmentVariable("PYTHON_HOME")

// defined in GitHub action setup-python

?? Environment.GetEnvironmentVariable("pythonLocation");

if (!string.IsNullOrEmpty(pyHome))

{

string dll = RuntimeInformation.IsOSPlatform(OSPlatform.Windows)

? Path.Combine(pyHome, Runtime.PythonDLL)

: Path.Combine(pyHome, "lib", Runtime.PythonDLL);

if (File.Exists(dll))

{

Runtime.PythonDLL = dll;

}

}

if (!Path.IsPathFullyQualified(Runtime.PythonDLL))

{

string[] paths = Environment.GetEnvironmentVariable("PATH")

.Split(Path.PathSeparator, StringSplitOptions.RemoveEmptyEntries);

foreach (string pathDir in paths)

{

string dll = Path.Combine(pathDir, Runtime.PythonDLL);

if (File.Exists(dll))

{

Runtime.PythonDLL = dll;

if (string.IsNullOrEmpty(pyHome))

{

pyHome = RuntimeInformation.IsOSPlatform(OSPlatform.Windows)

// on Windows, paths is PYTHON_HOME/dll

? Path.GetDirectoryName(dll)

// on *nix the path is HOME/lib/dll

: Path.GetDirectoryName(Path.GetDirectoryName(dll));

}

break;

}

}

}

if (!string.IsNullOrEmpty(pyHome))

{

PythonEngine.PythonHome = pyHome;

}

}

}

}