/stdhome

# copy_base.py

#

# Copyright (C) 2013 to 2014 Tim Marston <tim@edm.am>

#

# This file is part of stdhome (hereafter referred to as "this program").

# See http://ed.am/dev/stdhome for more information.

#

# This program 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 3 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, see <http://www.gnu.org/licenses/>.

import filecmp, os, shutil

from walker import Walker

import stdhome.the as the

class CopyBaseWalker( Walker ):

	"""The copy-base walker traverses a walklist ruthlessly mirroring src to dst.

	It is designed to be the base class of both the copy-in and copy-out walker,

	both of which are specialisations of this purpose.  See them for more

	information.

	"""

	accept_list = None

	def process( self, rel_file, src, dst ):

		# src entity is directory

		if src.type == 'd':

			# if dst entity doesn't exist, create directory (no need to recurse,

			# since we're copying the whole directory)

			if dst.type == '_':

				if the.verbose >= 2: self.print_op( rel_file, 'd>_' )

				shutil.copytree( src.file, dst.file, True )

			# if dst entity is a directory, copy permissions, as required (and

			# recurse)

			elif dst.type == 'd':

				# TODO: should check permission and only do as necessary

				if the.verbose >= 2: self.print_op( rel_file, 'd>d' )

				shutil.copystat( src.file, dst.file )

				return True

			# if dst entity is a symlink to a directory, and this is an

			# acceptable substitute, just recurse

			elif dst.link_type == 'd' and \

					self.accept_list and self.accept_list.match( rel_file ):

				if the.verbose >= 2: self.print_op( rel_file, 'd@d' )

				return True

			# if dst entity is a file or symlink in home dir, replace it with

			# directory (no need to recurse, since we're copying the whole

			# directory)

			elif dst.type == 'f' or dst.type == 'l':

				if the.verbose >= 2: self.print_op( rel_file, 'd>' + dst.type )

				os.unlink( dst.file )

				shutil.copytree( src.file, dst.file, True )

			else:

				raise NotImplementedError()

		# src entity is file

		elif src.type == 'f':

			# if dst entity doesn't exist, copy file

			if dst.type == '_':

				if the.verbose >= 2: self.print_op( rel_file, 'f>_' )

				shutil.copy( src.file, dst.file )

				shutil.copystat( src.file, dst.file )

			# if dst entity is a file, replace it only if it differs

			elif dst.type == 'f':

				if not filecmp.cmp( src.file, dst.file ):

					if the.verbose >= 2: self.print_op( rel_file, 'f>f' )

					os.unlink( dst.file )

					shutil.copy( src.file, dst.file )

					shutil.copystat( src.file, dst.file )

				else:

					if the.verbose >= 2: self.print_op( rel_file, 'f=f' )

			# if dst entity is a directory, replace it with file

			elif dst.type == 'd':

				if the.verbose >= 2: self.print_op( rel_file, 'f>d' )

				shutil.rmtree( dst.file )

				shutil.copy( src.file, dst.file )

				shutil.copystat( src.file, dst.file )

			# if dst entity is a symlink, replace it with file

			elif dst.type == 'l':

				if the.verbose >= 2: self.print_op( rel_file, 'f>l' )

				os.unlink( dst.file )

				shutil.copy( src.file, dst.file )

				shutil.copystat( src.file, dst.file )

			else:

				raise NotImplementedError()

		# src entity is a symlink

		elif src.type == 'l':

			# if dst entity doesn't exist, copy symlink

			if dst.type == '_':

				if the.verbose >= 2: self.print_op( rel_file, 'l>_' )

				os.symlink( os.readlink( src.file ), dst.file )

			# if dst entity is a symlink, replace it only if it differs

			elif dst.type == 'l':

				if os.readlink( src.file ) != os.readlink( dst.file ):

					if the.verbose >= 2: self.print_op( rel_file, 'l>l' )

					os.unlink( dst.file )

					os.symlink( os.readlink( src.file ), dst.file )

				else:

					if the.verbose >= 2: self.print_op( rel_file, 'l=l' )

			# if dst entity is a file, replace it with symlink

			elif dst.type == 'f':

				if the.verbose >= 2: self.print_op( rel_file, 'l>f' )

				os.unlink( dst.file )

				os.symlink( os.readlink( src.file ), dst.file )

			# if dst entity is a directory, and src entity is a symlink to a

			# directory, and this is an acceptable substitute, just recurse

			elif dst.type == 'd' and src.link_type == 'd' and \

					self.accept_list and self.accept_list.match( rel_file ):

				if the.verbose >= 2: self.print_op( rel_file, 'd@d' )

				return True

			# if dst entity is a directory, replace it with symlink

			elif dst.type == 'd':

				if the.verbose >= 2: self.print_op( rel_file, 'l>d' )

				shutil.rmtree( dst.file )

				os.symlink( os.readlink( src.file ), dst.file )

			else:

				raise NotImplementedError()

		# src entity is missing

		elif src.type == '_':

			# if dst entity doesn't exist, we're good

			if dst.type == '_':

				pass;

			# if dst entity is a file or symlink, delete it

			elif dst.type == 'f' or dst.type == 'l':

				if the.verbose >= 2: self.print_op( rel_file, '_>' + dst.type )

				os.unlink( dst.file )

			# if dst entity is a directory, delete it

			elif dst.type == 'd':

				if the.verbose >= 2: self.print_op( rel_file, '_>d' )

				shutil.rmtree( dst.file )

			else:

				raise NotImplementedError()

		# if we got here, we don't want to recurse...

		return False