# Copyright (C) 2007, 2008 by Intevation GmbH
# Authors:
# Bernhard Herzog <bh@intevation.de>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with the software for details.

"""Support code for debian packages"""

import os

from treepkg.util import extract_value_for_key
import treepkg.run


class DebianControlFile(object):

    """Parses a debian/control file and makes some of it available.

    Instances have the following instance variables:

      packages -- A list of the names of all packages defined in the
                  control file

      build_depends -- A list with the names of all package listed as
                       Build-Depends.
    """

    def __init__(self, filename):
        """Initialize the instance from a file given by filename"""
        self.packages = []
        self.build_depends = []
        self.parse(filename)

    def parse(self, filename):
        paragraph = []
        paragraphs = [paragraph]
        for lineno, line in enumerate(open(filename)):
            stripped = line.strip()
            if stripped.startswith("#"):
                continue
            if not stripped:
                if paragraph:
                    paragraph = []
                    paragraphs.append(paragraph)
            else:
                if line[:1] in " \t":
                    # handle continuation line
                    if paragraph:
                        paragraph[-1] += " " + stripped
                    else:
                        raise RuntimeError("%s:%d: Continuation line without"
                                           " preceding line"
                                           % (filename, lineno))
                else:
                    paragraph.append(stripped)
        if not paragraphs[-1]:
            del paragraphs[-1]

        self.handle_source_paragraph(paragraphs[0])
        for paragraph in paragraphs[1:]:
            self.handle_package_paragraph(paragraph)

    def handle_source_paragraph(self, paragraph):
        raw_deps = extract_value_for_key(paragraph, "Build-Depends:")
        for dep in raw_deps.split(","):
            # sanity check
            if dep.strip() != "":
                self.build_depends.append(dep.split()[0])

    def handle_package_paragraph(self, paragraph):
        package_name = extract_value_for_key(paragraph, "Package:")
        arch = extract_value_for_key(paragraph, "Architecture:")
        self.packages.append((package_name, arch))



def sign_file(filename, keyid):
    """Signs a debian .dsc or .control file"""
    contents = open(filename).read()

    # make sure contents ends with an empty line.  The signed files have
    # to have an empty line before the OpenPGP signature block
    if not contents.endswith("\n"):
        contents += "\n"
    contents += "\n"

    asc_file = filename + ".asc"
    treepkg.run.call(["gpg", "--clearsign", "--armor", "--textmode",
                      "--local-user", keyid, "-o", asc_file, "-"],
                     inputdata=contents, suppress_output=True)
    os.rename(asc_file, filename)