"""CMake helpers for xtensor-python.

This module provides CMake compatibility layer functions for projects

that use CMake to build C++ extensions with xtensor-python.

"""

import os

import platform

from pathlib import Path

from typing import Dict, List, Optional, Union

def get_cmake_dir() -> str:

"""Get the directory containing CMake configuration files.

Returns:

Path to the CMake configuration directory

"""

# For now, return the package directory since we don't have CMake files yet

# In a full implementation, this would point to installed CMake config files

package_dir = Path(__file__).parent

return str(package_dir)

def get_cmake_variables() -> Dict[str, str]:

"""Get CMake variables for xtensor-python configuration.

Returns:

Dictionary of CMake variable names and values

"""

from .build_helpers import get_include_dirs

from ._version import get_version_info, get_version_string

variables = {}

# Version information

try:

version_info = get_version_info()

version_string = get_version_string()

variables.update({

"xtensor-python_VERSION": version_string,

"xtensor-python_VERSION_MAJOR": str(version_info.major),

"xtensor-python_VERSION_MINOR": str(version_info.minor),

"xtensor-python_VERSION_PATCH": str(version_info.patch),

})

except Exception:

# Fallback values if version extraction fails

variables.update({

"xtensor-python_VERSION": "0.0.0",

"xtensor-python_VERSION_MAJOR": "0",

"xtensor-python_VERSION_MINOR": "0",

"xtensor-python_VERSION_PATCH": "0",

})

# Include directories

try:

include_dirs = get_include_dirs()

# Convert to CMake list format (semicolon-separated)

variables["xtensor-python_INCLUDE_DIRS"] = ";".join(include_dirs)

# Also provide the main xtensor-python include directory

package_dir = Path(__file__).parent

xtensor_python_include = str(package_dir / "include")

variables["xtensor-python_INCLUDE_DIR"] = xtensor_python_include

except Exception:

variables["xtensor-python_INCLUDE_DIRS"] = ""

variables["xtensor-python_INCLUDE_DIR"] = ""

# Compiler definitions

variables["xtensor-python_DEFINITIONS"] = ";".join([

"FORCE_IMPORT_ARRAY",

"NPY_NO_DEPRECATED_API=NPY_1_7_API_VERSION",

])

# Library information (header-only, so no actual libraries)

variables["xtensor-python_LIBRARIES"] = ""

variables["xtensor-python_LIBRARY_DIRS"] = ""

# CMake target information

variables["xtensor-python_TARGETS"] = "xtensor-python::xtensor-python"

return variables

def generate_cmake_config(output_dir: Union[str, Path]) -> Path:

"""Generate CMake configuration files for xtensor-python.

Args:

output_dir: Directory where CMake config files will be written

Returns:

Path to the generated config file

Raises:

OSError: If files cannot be written

"""

output_dir = Path(output_dir)

output_dir.mkdir(parents=True, exist_ok=True)

# Get CMake variables

variables = get_cmake_variables()

# Generate the main config file

config_content = _generate_config_file_content(variables)

config_file = output_dir / "xtensor-pythonConfig.cmake"

with open(config_file, 'w', encoding='utf-8') as f:

f.write(config_content)

# Generate version file

version_content = _generate_version_file_content(variables)

version_file = output_dir / "xtensor-pythonConfigVersion.cmake"

with open(version_file, 'w', encoding='utf-8') as f:

f.write(version_content)

return config_file

def _generate_config_file_content(variables: Dict[str, str]) -> str:

"""Generate the content for xtensor-pythonConfig.cmake file."""

content = f'''# xtensor-python CMake configuration file

# Generated by xtensor-python Python package

# Version information

set(xtensor-python_VERSION "{variables.get('xtensor-python_VERSION', '0.0.0')}")

set(xtensor-python_VERSION_MAJOR "{variables.get('xtensor-python_VERSION_MAJOR', '0')}")

set(xtensor-python_VERSION_MINOR "{variables.get('xtensor-python_VERSION_MINOR', '0')}")

set(xtensor-python_VERSION_PATCH "{variables.get('xtensor-python_VERSION_PATCH', '0')}")

# Include directories

set(xtensor-python_INCLUDE_DIRS "{variables.get('xtensor-python_INCLUDE_DIRS', '')}")

set(xtensor-python_INCLUDE_DIR "{variables.get('xtensor-python_INCLUDE_DIR', '')}")

# Compiler definitions

set(xtensor-python_DEFINITIONS "{variables.get('xtensor-python_DEFINITIONS', '')}")

# Libraries (header-only library, so empty)

set(xtensor-python_LIBRARIES "")

set(xtensor-python_LIBRARY_DIRS "")

# Find required dependencies

find_package(Python COMPONENTS Interpreter Development REQUIRED)

find_package(pybind11 REQUIRED)

# Find NumPy

if(NOT DEFINED NumPy_INCLUDE_DIR)

execute_process(

COMMAND "${{Python_EXECUTABLE}}" -c "import numpy; print(numpy.get_include())"

OUTPUT_VARIABLE NumPy_INCLUDE_DIR

OUTPUT_STRIP_TRAILING_WHITESPACE

RESULT_VARIABLE NumPy_RESULT

)

if(NOT NumPy_RESULT EQUAL 0)

message(FATAL_ERROR "Could not find NumPy include directory")

endif()

endif()

# Create imported target

if(NOT TARGET xtensor-python::xtensor-python)

add_library(xtensor-python::xtensor-python INTERFACE IMPORTED)

# Set include directories

set_target_properties(xtensor-python::xtensor-python PROPERTIES

INTERFACE_INCLUDE_DIRECTORIES "${{xtensor-python_INCLUDE_DIR}};${{NumPy_INCLUDE_DIR}}"

)

# Set compile definitions

set_target_properties(xtensor-python::xtensor-python PROPERTIES

INTERFACE_COMPILE_DEFINITIONS "FORCE_IMPORT_ARRAY;NPY_NO_DEPRECATED_API=NPY_1_7_API_VERSION"

)

# Set C++ standard requirement

set_target_properties(xtensor-python::xtensor-python PROPERTIES

INTERFACE_COMPILE_FEATURES "cxx_std_17"

)

# Link to pybind11

set_target_properties(xtensor-python::xtensor-python PROPERTIES

INTERFACE_LINK_LIBRARIES "pybind11::pybind11"

)

endif()

# Compatibility variables

set(xtensor-python_FOUND TRUE)

set(XTENSOR_PYTHON_FOUND TRUE)

# Helper function to create xtensor-python extensions

function(xtensor_python_add_module target_name)

cmake_parse_arguments(XTENSOR_PYTHON "" "" "SOURCES" ${{ARGN}})

pybind11_add_module(${{target_name}} ${{XTENSOR_PYTHON_SOURCES}})

target_link_libraries(${{target_name}} PRIVATE xtensor-python::xtensor-python)

# Set additional properties for better performance

target_compile_options(${{target_name}} PRIVATE

$<$<CXX_COMPILER_ID:GNU,Clang>:-O3 -ffast-math>

$<$<CXX_COMPILER_ID:MSVC>:/O2>

)

endfunction()

message(STATUS "Found xtensor-python: ${{xtensor-python_VERSION}}")

'''

return content

def _generate_version_file_content(variables: Dict[str, str]) -> str:

"""Generate the content for xtensor-pythonConfigVersion.cmake file."""

version = variables.get('xtensor-python_VERSION', '0.0.0')

content = f'''# xtensor-python CMake version file

# Generated by xtensor-python Python package

set(PACKAGE_VERSION "{version}")

# Check whether the requested PACKAGE_FIND_VERSION is compatible

if("${{PACKAGE_VERSION}}" VERSION_LESS "${{PACKAGE_FIND_VERSION}}")

set(PACKAGE_VERSION_COMPATIBLE FALSE)

else()

set(PACKAGE_VERSION_COMPATIBLE TRUE)

if("${{PACKAGE_VERSION}}" VERSION_EQUAL "${{PACKAGE_FIND_VERSION}}")

set(PACKAGE_VERSION_EXACT TRUE)

endif()

endif()

'''

return content

def get_cmake_prefix_path() -> List[str]:

"""Get CMake prefix paths for finding xtensor-python.

Returns:

List of paths to add to CMAKE_PREFIX_PATH

"""

paths = []

# Add the package directory

package_dir = Path(__file__).parent

paths.append(str(package_dir))

return paths

def get_cmake_find_commands() -> List[str]:

"""Get CMake commands for finding xtensor-python.

Returns:

List of CMake find_package commands

"""

commands = [

"find_package(xtensor-python REQUIRED)",

"target_link_libraries(your_target PRIVATE xtensor-python::xtensor-python)",

]

return commands

def print_cmake_info():

"""Print CMake configuration information for debugging."""

print("xtensor-python CMake Information")

print("=" * 40)

# CMake directory

cmake_dir = get_cmake_dir()

print(f"CMake directory: {cmake_dir}")

# CMake variables

variables = get_cmake_variables()

print("\nCMake variables:")

for name, value in variables.items():

print(f" {name}: {value}")

# Prefix paths

prefix_paths = get_cmake_prefix_path()

print(f"\nCMake prefix paths:")

for path in prefix_paths:

print(f" {path}")

# Find commands

commands = get_cmake_find_commands()

print(f"\nCMake usage:")

for cmd in commands:

print(f" {cmd}")

def create_cmake_example(output_dir: Union[str, Path]) -> Path:

"""Create an example CMakeLists.txt file showing xtensor-python usage.

Args:

output_dir: Directory where the example will be written

Returns:

Path to the generated example file

"""

output_dir = Path(output_dir)

output_dir.mkdir(parents=True, exist_ok=True)

example_content = '''# Example CMakeLists.txt for xtensor-python

cmake_minimum_required(VERSION 3.12)

project(xtensor_python_example)

# Set C++ standard

set(CMAKE_CXX_STANDARD 17)

set(CMAKE_CXX_STANDARD_REQUIRED ON)

# Find required packages

find_package(Python COMPONENTS Interpreter Development REQUIRED)

find_package(pybind11 REQUIRED)

find_package(xtensor-python REQUIRED)

# Create a pybind11 module

pybind11_add_module(example_module src/example.cpp)

# Link xtensor-python

target_link_libraries(example_module PRIVATE xtensor-python::xtensor-python)

# Alternative: use the helper function

# xtensor_python_add_module(example_module SOURCES src/example.cpp)

# Compiler-specific options for better performance

target_compile_definitions(example_module PRIVATE VERSION_INFO="${EXAMPLE_VERSION_INFO}")

'''

example_file = output_dir / "CMakeLists.txt.example"

with open(example_file, 'w', encoding='utf-8') as f:

f.write(example_content)

return example_file

# Backward compatibility aliases

get_include_dir = get_cmake_dir

get_cmake_include_dirs = lambda: get_cmake_variables().get("xtensor-python_INCLUDE_DIRS", "").split(";")