"""
See BENTO_BUILD.txt.

Caveats:

    - no automatic detection for BLAS/LAPACK/etc... You need to set it up
      manually for now (except on Mac OS X and Debian/Ubuntu). The upside is
      that it is extremely easy to do so
    - bento is still in flux, and some things may changes between releases.
"""
    
import os
import sys
import subprocess

# Ugly but necessary hack: import numpy here so that wscript in sub directories
# will see this numpy and not an already installed one
import __builtin__
__builtin__.__NUMPY_SETUP__ = True

import waflib

from numpy.distutils.conv_template \
    import \
        process_str as process_c_str

from bento.commands import hooks
from bento.utils.utils \
    import \
        cmd_is_runnable
from bento.backends.waf_backend \
    import \
        WAF_TOOLDIR
from bento.backends.waf_tools \
    import \
        blas_lapack

sys.path.insert(0, os.getcwd())
try:
    _SETUP_PY = __import__("setup")
finally:
    sys.path.pop(0)

def compute_git_revision(top_node):
    git_repo_node = top_node.find_node(".git")
    if git_repo_node and cmd_is_runnable(["git", "--version"]):
        s = subprocess.Popen(["git", "rev-parse", "HEAD"],
                stdout=subprocess.PIPE, stderr=subprocess.STDOUT, cwd=top_node.abspath())
        out = s.communicate()[0]
        return out.decode().strip()
    else:
        return ""

def _register_metadata(context):
    git_revision = compute_git_revision(context.top_node)
    full_version = context.pkg.version
    if not _SETUP_PY.ISRELEASED:
        full_version += '.dev-' + git_revision[:7]

    context.register_metadata("git_revision", git_revision)
    context.register_metadata("is_released", _SETUP_PY.ISRELEASED)
    context.register_metadata("full_version", full_version)

def _generate_cython():
    print("Cythonizing sources")
    cwd = os.path.abspath(os.path.dirname(__file__))
    p = subprocess.call([sys.executable,
                          os.path.join(cwd, 'tools', 'cythonize.py'),
                          'numpy'],
                         cwd=cwd)
    if p != 0:
        raise RuntimeError("Running cythonize failed!")

@hooks.post_configure
def post_configure(context):
    conf = context.waf_context
    if conf.env["CC_NAME"] == "gcc":
        conf.env.CFLAGS_PYEXT.append("-Wfatal-errors")

    conf.load("arch", tooldir=[WAF_TOOLDIR])
    if sys.platform == "darwin":
        conf.env["MACOSX_DEPLOYMENT_TARGET"] = "10.4"
        conf.check_cc_default_arch()
        archs = [conf.env.DEFAULT_CC_ARCH]
        conf.env.ARCH = archs

    blas_lapack.check_blas_lapack(context)

    _generate_cython()

@hooks.pre_build
def pre_build(context):
    _register_metadata(context)

@hooks.pre_sdist
def pre_sdist(context):
    _register_metadata(context)

@hooks.options
def options(global_context):
    blas_lapack.add_options(global_context)


class CTemplateTask(waflib.Task.Task):
    color = 'BLUE'
    before = ['c']
    def run(self):
        s = self.inputs[0]
        cnt = s.read()
        writestr = process_c_str(cnt)
        o = self.outputs[0]
        o.write(writestr)

@waflib.TaskGen.extension(".src")
def c_template(self, node):
    outs = []
    outs.append(node.change_ext(""))

    tsk = self.create_task('CTemplateTask', node, outs)
    if "c" in self.features and not node.name[-6:] == (".h.src"):
        self.source.append(outs[0])