#!/usr/bin/python3
# DpkgControl -*- mode: python; coding: utf-8 -*-
#
# This module implements control file parsing.
#
# Copyright (c) 2001 Adam Heath <doogie@debian.org>
#
# DpkgParagraph is a low-level class, that reads/parses a single paragraph
# from a file object.
#
# DpkgControl uses DpkgParagraph in a loop, pulling out the value of a
# defined key(package), and using that as a key in it's internal
# dictionary.
#
# DpkgSourceControl grabs the first paragraph from the file object, stores
# it in object.source, then passes control to DpkgControl.load, to parse
# the rest of the file.
#
# To test this, pass it a filetype char, a filename, then, optionally,
# the key to a paragraph to display, and if a fourth arg is given, only
# show that field.

# This file is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

from .DpkgDatalist import *
from .SignedFile import *

class DpkgParagraph(DpkgOrderedDatalist):
    trueFieldCasing = {}

    def load( self, f ):
        """Paragraph data from a file object"""
        key = None
        while True:
            line = f.readline()
            if not line:
                return
            # skip blank lines until we reach a paragraph
            if line == '\n':
                if not self:
                    continue
                else:
                    return
            if line[ 0 ] != ' ':
                ( truekey, value ) = line.split( ":", 1 )
                key = truekey.lower()
                self.trueFieldCasing[ key ] = truekey
                self[ key ] = value.strip()
            else:
                self[ key ] += "\n%s" % line.strip()

    def _storeField( self, f, value, lead = " " ):
        value = "\n".join(list(map( lambda v, lead = lead: lead + v if v else "", value.splitlines() )))
        f.write( "%s\n" % value )

    def _store( self, f ):
        """Write our paragraph data to a file object"""
        for ( key, value ) in list(self.items()):
            truekey = self.trueFieldCasing[ key ]
            f.write( "%s:" % truekey )
            self._storeField( f, value )

class DpkgControl(DpkgParagraph):
    def load( self, f, source = False ):
        while True:
            para = DpkgParagraph()
            para.load( f )
            if not para:
                break
            if "source" not in para:
                self[ para[ "package" ] ] = para
            elif source:
                self[ "source" ] = para

    def _store( self, f ):
        """Write our control data to a file object"""
        keys = list(self.keys())
        while keys:
            self[ keys.pop( 0 ) ]._store( f )
            if keys:
                f.write( "\n" )

class DpkgSourceControl(DpkgControl):
    def load( self, f ):
        f = SignedFile( f )
        DpkgControl.load( self, f, source = True )

if __name__ == "__main__":
    import sys
    types = { 'p': DpkgParagraph, 'c': DpkgControl, 's': DpkgSourceControl }
    type = sys.argv[ 1 ]
    if type not in types:
        print( "Unknown type `%s'!" % type )
        sys.exit( 1 )
    file = open( sys.argv[ 2 ], "r" )
    data = types[ type ]()
    data.load( file )
    if len( sys.argv ) > 3:
        rargs = sys.argv[ 3: ]
        if type != 'p':
            data = data[ rargs.pop( 0 ) ]
        if rargs:
            data._storeField( sys.stdout, data[ rargs[ 0 ].lower() ], "" )
        else:
            data._store( sys.stdout )
    else:
        data._store( sys.stdout )

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