#!/usr/bin/env python
#
# Copyright (c) 2006-2007, Hans Meine <hans_meine@gmx.net>
#  All rights reserved.
#
# This is licensed according to the new BSD license.
# Please send patches / comments, I would be happy about any feedback.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# * Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in the
#   documentation and/or other materials provided with the distribution.
#
# * Neither the name of the University of Hamburg nor the names of its
#   contributors may be used to endorse or promote products derived from
#   this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

import os, sys

# USAGE: cvs-chroot [old] [new]

from optparse import OptionParser

op = OptionParser(
	usage = "%prog [options] [<oldroot> <newroot>]",
	description = "Recursively looks for CVS/Root files, and changes occurences of <oldroot> to <newroot> (without arguments, just displays current roots).\nUse empty strings for <oldroot> or <newroot> to remove/create CVS/Root files.")
op.add_option("-v", "--verbose", action = "count", default = 1,
			  dest = "verbosity", help = "verbose output (default)")
op.add_option("-q", "--quiet", action = "store_const", const = 0,
			  dest = "verbosity", help = "quite mode (only errors)")
op.add_option("-c", "--columns", action = "store_true", default = False,
			  dest = "outputColumns", help = "format output in columns")
op.add_option("-s", "--skiplinks", action = "store_true", default = False,
			  dest = "skipLinks", help = "skip symbolic links to directories (default: follow)")
options, args = op.parse_args()

changeMode = (len(args) == 2)
if changeMode:
	sourceRoot = args[0]
	if not sourceRoot or sourceRoot == "<none>":
		sourceRoot = None
	targetRoot = args[1]
	if not targetRoot:
		targetRoot = None

LOG_ERROR = 0
LOG_NORMAL = 1
LOG_VERBOSE = 2

def log(level, str):
	if level:
		if level <= options.verbosity:
			sys.stdout.write(str)
	else:
		sys.stderr.write(str)

def recursiveCVSDirs(startDir):
	result = []
	for name in os.listdir(startDir):
		subPath = os.path.join(startDir, name)
		if os.path.isdir(subPath) and (
			not options.skipLinks or not os.path.islink(subPath)):
			if name == "CVS":
				result.append(startDir[2:])
			else:
				result.extend(recursiveCVSDirs(subPath))
	return result

# ATTENTION: first 2 chars from paths are stripped, expected to be "./"
cvsPaths = recursiveCVSDirs(".")

formatStr = "%s: %s\n"

if options.outputColumns:
	maxLen = 0
	for cp in cvsPaths:
		maxLen = max(maxLen, len(cp))
	formatStr = "%-"+str(maxLen)+"s | %s\n"

for cvsPath in cvsPaths:
	if not cvsPath:
		cvsPath = "." # nicer display

	rootPath = os.path.join(cvsPath, "CVS/Root")
	if os.path.isfile(rootPath):
		root = file(rootPath).readline()[:-1]
	else:
		root = None

	if not changeMode:
		if root:
			log(LOG_NORMAL, formatStr % (cvsPath, root))
		else:
			log(LOG_VERBOSE, formatStr % (cvsPath, "<none>"))
	else:
		if root == sourceRoot:
			if targetRoot:
				file(rootPath, "w").write(targetRoot + "\n")
				log(LOG_NORMAL, formatStr % (cvsPath, "changed"))
			else:
				os.unlink(rootPath)
				log(LOG_NORMAL, formatStr % (cvsPath, "removed"))
		else:
			log(LOG_VERBOSE, formatStr % (cvsPath, "IGNORED"))