'''
sphinx_pipe.py - this file is part of S3QL.

Implements a Sphinx extension that provides a `pipeinclude` directive
to include the output of a program.


Copyright © 2008 Nikolaus Rath <Nikolaus@rath.org>

This work can be distributed under the terms of the GNU GPLv3.
'''

import os.path
import shlex
import subprocess
import sys
import tempfile

from docutils.parsers.rst.directives.misc import Include
from docutils.utils.error_reporting import SafeString


class PipeInclude(Include):
    """
    Include program output as ReST source.
    """

    def run(self):
        # To maximize code reuse, we just write the output in a temporary
        # file and call the base class. Otherwise we'd have to copy & paste
        # all the code to handle start-line, end-line etc options.

        source = self.state_machine.input_lines.source(
            self.lineno - self.state_machine.input_offset - 1
        )
        source_dir = os.path.dirname(os.path.abspath(source))

        command = self.arguments[0]
        command_list = shlex.split(command)

        if command_list[0] == 'python':
            command_list[0] = sys.executable

        with tempfile.NamedTemporaryFile() as fh:
            exitcode = subprocess.call(command_list, stdout=fh, cwd=source_dir)
            if exitcode != 0:
                raise self.severe(
                    'Problems with "%s" directive:\n'
                    'Command %s returned with exit code %d'
                    % (self.name, SafeString(command), exitcode)
                )

            fh.flush()
            self.arguments[0] = fh.name
            return super().run()


def setup(app):
    app.add_directive('pipeinclude', PipeInclude)
