/stdhome

# bzr.py

#

# Copyright (C) 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 subprocess, os, re, shutil

from subprocess import Popen

import StringIO

from vcs import Vcs

from stdhome import the

class BzrVcs( Vcs ):

	def __init__( self, dir ):

		"""Init class

		@param dir the fully-qualified directory to work in.

		"""

		self.dir = dir

	def init( self ):

		"""Create a new, empty branch

		"""

		# the directory shouldn't exist

		os.mkdir( self.dir )

		# bzr init

		try:

			self.run( [ 'bzr', 'init', '.' ] )

		except self.VcsError as e:

			# attempt to clean-up dir

			try:

				shutil.rmtree( self.dir )

			except OSError:

				pass

			raise

	def checkout( self, url ):

		"""Checkout a new copy of a remote branch.

		@param url the remote repository URL

		"""

		# the directory shouldn't exist

		os.mkdir( self.dir )

		# bzr co

		try:

			self.run( [ 'bzr', 'checkout', url, '.' ] )

		except self.VcsError as e:

			# attempt to clean-up dir

			try:

				shutil.rmtree( self.dir )

			except OSError:

				pass

			raise

	def get_revno( self ):

		"""Obtain some sort of revision identifier

		"""

		# bzr revert

		output = self.run( [ 'bzr', 'revno', '--tree' ] )

		# parse revno

		buf = StringIO.StringIO( output )

		return buf.readline().rstrip()

	def revert( self, revno = None ):

		"""Revert the branch so that there are no outstanding changes or unknown files.

		If a revno is supplied, then the repository is reverted to that

		revision.

		"""

		# bzr st

		output = self.run( [ 'bzr', 'status' ] )

		files = self.parse_file_blocks( output )

		# remove kind changed files (or they can cause `bzr revert` to break in

		# strange situations, like when a directory has been replaced with a

		# symlink to a non-existant file)

		if 'kind changed' in files:

			for file in files[ 'kind changed' ]:

				matches = re.match( r'(.+?)[/@+]? \([^)]+\)', file )

				if not matches:

					raise RunTimeError(

						'failed to parse bzr kind change: %s' % file )

				file = matches.group( 1 )

				if the.verbose >= 2: print "removing (kind changed): " + file

				full_file = os.path.join( self.dir, file )

				if os.path.isfile( full_file ) or os.path.islink( full_file ):

					os.unlink( full_file )

				elif os.path.isdir( full_file ):

					shutil.rmtree( full_file )

				else:

					raise RuntimeError( 'exotic file in repo: %s' % file )

		# bzr revert

		self.run( [ 'bzr', 'revert', '--no-backup' ] )

		# bzr st

		output = self.run( [ 'bzr', 'status' ] )

		files = self.parse_file_blocks( output )

		# remove unknown files

		if 'unknown' in files:

			for file in files[ 'unknown' ]:

				if the.verbose >= 2: print "removing (unknown): " + file

				full_file = os.path.join( self.dir, file )

				if os.path.isfile( full_file ):

					os.unlink( full_file )

				elif os.path.isdir( full_file ):

					shutil.rmtree( full_file )

				else:

					raise RuntimeError( 'exotic file in repo: %s' % file )

		# if a revision identifyer has been given, update to that

		if revno is not None:

			# bzr update

			self.run( [ 'bzr', 'update', '-r', revno ] )

	def update( self ):

		"""Update the branch, pulling down any upstream changes and merging them.  This

		method returns a list of the files that were modified as part of this

		operation.

		"""

#		WARNING: the following might cause bzr to ask for your ssh password more than

#		once during an update!!!

#

#		# get revno

#		revno = self.get_revno()

#

#		# update to current revision (pull in history without updating tree)

#		self.run( [ 'bzr', 'update', '-r', revno ] )

#

#		# get log output

#		next_revno = str( int( revno ) + 1 )

#		output = self.run( [ 'bzr', 'log', '-r', next_revno + '..' ] )

#

#		# parse output

#		keep_files = list()

#		buf = StringIO.StringIO( output )

#		in_message = False

#		for line in buf:

#			line = line.rstrip( '\n' )

#			if line.lower() == 'message:':

#				in_message = True

#			elif in_message:

#				if line[ : 2 ] != '  ':

#					in_message = False

#				else:

#					line = line[ 2 : ]

#

#					# process directives

#					if line[ : 6 ].lower() == 'keep: ':

#						file = line[ 6 : ]

#						if file in rename_files: file = rename_files[ file ]

#						keep_files.append( file )

#					elif line[ : 8 ].lower() == 'rename: ':

#						rename_from = line[ 8 : ]

#					elif line[ : 4 ].lower() == 'to: ':

#						if rename_from in rename_files:

#							rename_from = rename_files[ rename_from ]

#						rename_files[ line[ 4 : ] ] = rename_from

		# bzr update properly

		output = self.run( [ 'bzr', 'update' ] )

		# parse output (see logic in report() in bzrlib/delta.py)

		files = list()

		buf = StringIO.StringIO( output )

		for line in buf:

			if not re.search( '^[-R+ ?][K NMD!][* ] ', line ): continue

			line = line.rstrip()

			if the.verbose >= 2: print '  %s' % line

			# renames show before and after file names

			matches = re.search( '^R.. (.*?)[/@+]? => (.*?)[/@+]?$', line )

			if matches:

				files.append( matches.group( 1 ) )

				files.append( matches.group( 2 ) )

				continue

			# kind changes shows the same name twice

			matches = re.search( '^.K. (.*?)[/@+]? => (.*?)[/@+]?$', line )

			if matches:

				files.append( matches.group( 1 ) )

				continue

			# other entries have only one filename

			matches = re.search( '^... (.*?)[/@+]?$', line )

			if matches:

				files.append( matches.group( 1 ) )

				continue

			raise RuntimeError(

				'failed to parse bzr update output line:\n%s' % line )

		return files

	def has_changes( self ):

		"""Check if the branch has any local modifications.

		"""

		# bzr status

		output = self.run( [ 'bzr', 'status', '--no-pending' ] )

		# parse output

		files = self.parse_file_blocks( output )

		return True if len( files ) else False

	def get_conflicts( self ):

		"""Return a list of files that have conflicts.

		"""

		# bzr status

		output = self.run( [ 'bzr', 'status', '--no-pending' ] )

		# parse output

		files = self.parse_file_blocks( output )

		return files['conflicts'] if 'conflicts' in files else None

	def run( self, cmd ):

		if the.verbose >= 2: print 'exec: %s' % ' '.join( cmd )

		p = Popen( cmd, cwd = self.dir,

				   stdout = subprocess.PIPE, stderr = subprocess.STDOUT )

		output = p.communicate()[ 0 ]

		if p.returncode > 0:

			raise self.VcsError( ' '.join( cmd[ : 2 ] ), output )

		return output

	def parse_file_blocks( self, output ):

		res = dict()

		current = None

		buf = StringIO.StringIO( output )

		for line in buf:

			matches = re.search( '^([a-z ]+):$', line, re.I )

			if matches:

				current = matches.group( 1 )

				continue

			if current:

				matches = re.search( '^  ([^ ].*)$', line )

				if matches:

					if not current in res:

						res[ current ] = list()

					res[ current ].append( matches.group( 1 ) )

					continue

			if re.search( '^[0-9]+ shel(?:f|ves) exists?', line ): continue

			if re.search( '^working tree is out of date', line ): continue

			raise self.ParseError( "unrecognised line: %s" % line )

		return res

	class ParseError( Exception ):

		pass