dnl Functions for Python bindings
dnl
dnl Version: 20140622

dnl Function to check if the python binary is available
dnl "python python# python#.#"
AC_DEFUN([AX_PROG_PYTHON],
 [AS_IF(
  [test "x${PYTHON_VERSION}" != x],
  [ax_python_progs="python${PYTHON_VERSION}"],
  [ax_python_progs="python python2 python2.7 python2.6 python2.5 python3 python3.4 python3.3 python3.2 python3.1 python3.0"])
 AC_CHECK_PROGS(
  [PYTHON],
  [$ax_python_progs])
 AS_IF(
  [test "x${PYTHON}" != x],
  [ax_prog_python_version=`${PYTHON} -c "import sys; sys.stdout.write(sys.version[[:3]])" 2>/dev/null`;
  AC_SUBST(
   [PYTHON_VERSION],
   [$ax_prog_python_version])

  ax_prog_python_platform=`${PYTHON} -c "import sys; sys.stdout.write(sys.platform)" 2>/dev/null`;
  AC_SUBST(
   [PYTHON_PLATFORM],
   [$ax_prog_python_platform])
  ],
  [AC_MSG_ERROR(
   [Unable to find python])
  ])
 AC_SUBST(
  [PYTHON],
  [$PYTHON])
 ])

dnl Function to check if the python-config binary is available
dnl "python${PYTHON_VERSION}-config python-config"
AC_DEFUN([AX_PROG_PYTHON_CONFIG],
 [AS_IF(
  [test "x${PYTHON}" != x],
  [AC_CHECK_PROGS(
   [PYTHON_CONFIG],
   [python${PYTHON_VERSION}-config python-config])
  ])
 AS_IF(
  [test "x${PYTHON_CONFIG}" = x],
  [AC_MSG_ERROR(
   [Unable to find python-config])
  ])
 AC_SUBST(
  [PYTHON_CONFIG],
  [$PYTHON_CONFIG])
 ])

dnl Function to detect if Python build environment is available
AC_DEFUN([AX_PYTHON_CHECK],
 [AX_PROG_PYTHON
 AX_PROG_PYTHON_CONFIG

 AS_IF(
  [test "x${PYTHON_CONFIG}" != x],
  [dnl Check for Python includes
  PYTHON_INCLUDES=`${PYTHON_CONFIG} --includes 2>/dev/null`;

  AC_MSG_CHECKING(
   [for Python includes])
  AC_MSG_RESULT(
   [$PYTHON_INCLUDES])

  dnl Check for Python libraries
  PYTHON_LDFLAGS=`${PYTHON_CONFIG} --ldflags 2>/dev/null`;

  AC_MSG_CHECKING(
   [for Python libraries])
  AC_MSG_RESULT(
   [$PYTHON_LDFLAGS])

  dnl Check for the existence of Python.h
  BACKUP_CPPFLAGS="${CPPFLAGS}"
  CPPFLAGS="${CPPFLAGS} ${PYTHON_INCLUDES}"

  AC_CHECK_HEADERS(
   [Python.h],
   [ac_cv_header_python_h=yes],
   [ac_cv_header_python_h=no])

  CPPFLAGS="${BACKUP_CPPFLAGS}"
 ])

 AS_IF(
  [test "x${ac_cv_header_python_h}" != xyes],
  [ac_cv_enable_python=no],
  [ac_cv_enable_python=$PYTHON_VERSION
  AC_SUBST(
   [PYTHON_CPPFLAGS],
   [$PYTHON_INCLUDES])

  AC_SUBST(
   [PYTHON_LDFLAGS],
   [$PYTHON_LDFLAGS])

  dnl Check for Python prefix
  AS_IF(
   [test "x${ac_cv_with_pyprefix}" = x || test "x${ac_cv_with_pyprefix}" = xno],
   [ax_python_prefix="\${prefix}"],
   [ax_python_prefix=`${PYTHON_CONFIG} --prefix 2>/dev/null`])

  AC_SUBST(
   [PYTHON_PREFIX],
   [$ax_python_prefix])

  dnl Check for Python exec-prefix
  AS_IF(
   [test "x${ac_cv_with_pyprefix}" = x || test "x${ac_cv_with_pyprefix}" = xno],
   [ax_python_exec_prefix="\${exec_prefix}"],
   [ax_python_exec_prefix=`${PYTHON_CONFIG} --exec-prefix 2>/dev/null`])

  AC_SUBST(
   [PYTHON_EXEC_PREFIX],
   [$ax_python_exec_prefix])

  dnl Check for Python library directory
  ax_python_pythondir_suffix=`${PYTHON} -c "import sys; import distutils.sysconfig; sys.stdout.write(distutils.sysconfig.get_python_lib(0, 0, prefix=''))" 2>/dev/null`;

  AS_IF(
   [test "x${ac_cv_with_pythondir}" = x || test "x${ac_cv_with_pythondir}" = xno],
   [AS_IF(
    [test "x${ac_cv_with_pyprefix}" = x || test "x${ac_cv_with_pyprefix}" = xno],
    [ax_python_pythondir="${ax_python_prefix}/${ax_python_pythondir_suffix}"],
    [ax_python_pythondir=`${PYTHON} -c "import distutils.sysconfig; print distutils.sysconfig.get_python_lib() " 2>/dev/null`])],
   [ax_python_pythondir=$ac_cv_with_pythondir])

  AC_SUBST(
   [pythondir],
   [$ax_python_pythondir])

  dnl Check for Python platform specific library directory
  ax_python_pyexecdir_suffix=`${PYTHON} -c "import sys; import distutils.sysconfig; sys.stdout.write(distutils.sysconfig.get_python_lib(1, 0, prefix=''))" 2>/dev/null`;
  ax_python_library_dir=`${PYTHON} -c "import distutils.sysconfig; print distutils.sysconfig.get_python_lib(True) " 2>/dev/null`;

  AS_IF(
   [test "x${ac_cv_with_pyprefix}" = x || test "x${ac_cv_with_pyprefix}" = xno],
   [ax_python_pyexecdir="${ax_python_exec_prefix}/${ax_python_pyexecdir_suffix}"],
   [ax_python_pyexecdir=$ax_python_library_dir])

  AC_SUBST(
   [pyexecdir],
   [$ax_python_pyexecdir])

  AC_SUBST(
   [PYTHON_LIBRARY_DIR],
   [$ax_python_pyexecdir_suffix])

  AC_SUBST(
   [PYTHON_PACKAGE_DIR],
   [$ax_python_library_dir])
  ])
 ])

dnl Function to detect if to enable Python
AC_DEFUN([AX_PYTHON_CHECK_ENABLE],
 [dnl Deprecated way of enabling Python bindings
 AX_COMMON_ARG_ENABLE(
  [python],
  [python],
  [build Python bindings],
  [no])
 AX_COMMON_ARG_WITH(
  [pythondir],
  [pythondir],
  [use to specify the Python directory (pythondir)],
  [no],
  [no])
 AX_COMMON_ARG_WITH(
  [pyprefix],
  [pyprefix],
  [use `python-config --prefix' to determine the prefix of pythondir instead of --prefix],
  [no],
  [no])

 AS_IF(
  [test "x${ac_cv_enable_python}" != xno],
  [AX_PYTHON_CHECK])

 AS_IF(
  [test "x${ac_cv_enable_python}" != xno],
  [AC_DEFINE(
   [HAVE_PYTHON],
   [1],
   [Define to 1 if you have Python])
  ])

 AM_CONDITIONAL(
  HAVE_PYTHON,
  [test "x${ac_cv_enable_python}" != xno])
])