#!/usr/bin/env python3
import os
import argparse
import shlex

# Argument parsing
parser = argparse.ArgumentParser(
    description="Generate a meson crossfile based on environment variables")
parser.add_argument('file', type=argparse.FileType('w', encoding='UTF-8'),
    help="output file")
args = parser.parse_args()

# Helper to add env variable value to crossfile
def _add_environ_val(meson_key, env_key):
    env_value = os.environ.get(env_key, '')
    args.file.write("{} = '{}'\n".format(meson_key, env_value))

# Helper to add env variable array to crossfile
def _add_environ_arr(meson_key, env_key):
    env_values = shlex.split(os.environ.get(env_key, ''))
    arr_string = (', '.join("'" + item + "'" for item in env_values))
    args.file.write("{} = [{}]\n".format(meson_key, arr_string))

# Generate meson crossfile
args.file.write("# Automatically generated by contrib makefile\n")

# Binaries section
args.file.write("\n[binaries]\n")
_add_environ_val('c', 'CC')
_add_environ_val('cpp', 'CXX')
_add_environ_val('ar', 'AR')
_add_environ_val('strip', 'STRIP')
_add_environ_val('pkgconfig', 'PKG_CONFIG')
_add_environ_val('windres', 'WINDRES')

# Properties section
args.file.write("\n[properties]\n")
args.file.write("needs_exe_wrapper = true\n")
_add_environ_arr('c_args', 'CFLAGS')
_add_environ_arr('c_link_args', 'LDFLAGS')
_add_environ_arr('cpp_args', 'CXXFLAGS')
_add_environ_arr('cpp_link_args', 'LDFLAGS')

# Host machine section
args.file.write("\n[host_machine]\n")
_add_environ_val('system', 'HOST_SYSTEM')
_add_environ_val('cpu_family', 'HOST_ARCH')
args.file.write("endian = 'little'\n")

# Get first part of triplet
cpu = os.environ.get('HOST', '').split('-')[0]
args.file.write("cpu = '{}'\n".format(cpu))