#!/usr/bin/python
#
# Copyright (C) 2010, Benjamin Drung <bdrung@ubuntu.com>
#
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

import debian.changelog
import debian.deb822
import debian.debian_support
import launchpadlib.launchpad
import optparse
import os
import pwd
import re
import shutil
import subprocess
import sys
import urllib

USER_ABORT = 2

class BugTask(object):
	def __init__(self, bug_task, launchpad):
		self.bug_task = bug_task
		self.launchpad = launchpad

		components = re.split(" \(| ", self.bug_task.bug_target_name.strip(")"))
		assert len(components) >= 1 and len(components) <= 3
		if len(components) == 1:
			self.package = None
			self.project = components[0]
			self.series = None
		elif len(components) == 2:
			self.package = components[0]
			self.project = components[1].lower()
			self.series = None
		elif len(components) == 3:
			self.package = components[0]
			self.project = components[1].lower()
			self.series = components[2].lower()

	def download_source(self):
		source_files = self.get_source().sourceFileUrls()
		dsc_file = None
		for url in source_files:
			filename = urllib.unquote(os.path.basename(url))
			Print.info("Downloading %s..." % (filename))
			urllib.urlretrieve(url, filename)
			if url.endswith(".dsc"):
				dsc_file = filename
		return os.path.join(os.getcwd(), dsc_file)

	def get_branch_link(self):
		return "lp:" + self.project + "/" + self.get_series() + "/" + self.package

	def get_long_info(self):
		return "Bug task: " + str(self.bug_task) + "\n" + \
				"Package: " + str(self.package) + "\n" + \
				"Project: " + str(self.project) + "\n" + \
				"Series: " + str(self.series)

	def get_package_and_series(self):
		result = self.package
		if self.series:
			result += " (" + self.series + ")"
		return result

	def get_previous_version(self):
		if self.is_merge():
			previous_version = self.get_latest_released_version()
		else:
			previous_version = self.get_version()
		return previous_version

	def get_series(self, latest_release=False):
		if self.series is None or latest_release:
			return self.launchpad.distributions[self.project].current_series.name
		else:
			return self.series

	def get_short_info(self):
		return self.bug_task.bug_target_name + ": " + self.bug_task.status

	def get_source(self, latest_release=False):
		assert self.package is not None

		if self.is_merge() and not latest_release:
			project = "debian"
			title = self.bug_task.title.lower().split()
			if "experimental" in title:
				series = "experimental"
			elif "testing" in title:
				# TODO: Do not hard code series!
				series = "squeeze"
			else:
				series = "sid"
			status = "Pending"
		else:
			project = self.project
			series = self.get_series(latest_release)
			status = "Published"

		dist = self.launchpad.distributions[project]
		archive = dist.getArchive(name="primary")
		distro_series = dist.getSeries(name_or_version=series)
		published = archive.getPublishedSources(source_name=self.package,
				distro_series=distro_series, status=status, exact_match=True)

		latest_source = None
		for source in published:
			if source.pocket in ('Release', 'Security', 'Updates', 'Proposed'):
				latest_source = source
				break
		return latest_source

	def get_version(self):
		return debian.debian_support.Version(self.get_source().source_package_version)

	def get_latest_released_version(self):
		version = self.get_source(True).source_package_version
		return debian.debian_support.Version(version)

	def is_complete(self):
		return self.bug_task.is_complete

	def is_merge(self):
		bug = self.bug_task.bug
		return "merge" in bug.title.lower().split(" ") or "merge" in bug.tags

	def is_ubuntu_task(self):
		return self.project == "ubuntu"


class Patch(object):
	def __init__(self, patch_file):
		self.patch_file = patch_file
		self.full_path = os.path.realpath(self.patch_file)
		assert os.path.isfile(self.full_path), "%s does not exist." % (self.full_path)
		cmd = ["diffstat", "-l", "-p0", self.full_path]
		changed_files = subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()[0]
		self.changed_files = filter(lambda l: l != "", changed_files.split("\n"))

	def get_name(self):
		return self.patch_file

	def get_strip_level(self):
		strip_level = None
		if self.is_debdiff():
			changelog = filter(lambda f: f.endswith("debian/changelog"), self.changed_files)[0]
			strip_level = len(changelog.split(os.sep)) - 2
		return strip_level

	def is_debdiff(self):
		return len(filter(lambda f: f.endswith("debian/changelog"), self.changed_files)) > 0


class Print(object):
	script_name = os.path.basename(sys.argv[0])
	verbose = False

	@classmethod
	def command(self, cmd):
		if self.verbose:
			for i in xrange(len(cmd)):
				if cmd[i].find(" ") >= 0:
					cmd[i] = '"' + cmd[i] + '"'
			print "%s: I: %s" % (script_name, " ".join(cmd))

	@classmethod
	def debug(self, message):
		if self.verbose:
			print "%s: D: %s" % (script_name, message)

	@classmethod
	def error(self, message):
		print >> sys.stderr, "%s: Error: %s" % (script_name, message)

	@classmethod
	def info(self, message):
		if self.verbose:
			print "%s: I: %s" % (script_name, message)

	@classmethod
	def normal(self, message):
		print "%s: %s" % (script_name, message)

	@classmethod
	def set_verbosity(self, verbose):
		self.verbose = verbose


def get_source_package_name(bug_task):
	package = None
	if bug_task.bug_target_name != "ubuntu":
		assert bug_task.bug_target_name.endswith("(Ubuntu)")
		package = bug_task.bug_target_name.split(" ")[0]
	return package

def get_user_shell():
	try:
		shell = os.environ["SHELL"]
	except KeyError:
		shell = pwd.getpwuid(os.getuid())[6]
	return shell

def input_number(question, min_number, max_number, default=None):
	if default:
		question += " [%i]? " % (default)
	else:
		question += "? "
	selected = None
	while selected < min_number or selected > max_number:
		selected = raw_input(question).strip()
		if default and selected == "":
			selected = default
		else:
			try:
				selected = int(selected)
				if selected < min_number or selected > max_number:
					print "Please input a number between %i and %i." % \
							(min_number, max_number)
			except ValueError:
				print "Please input a number."
	assert type(selected) == int
	return selected

def boolean_question(question, default):
	if default is True:
		question += " [Y/n]? "
	else:
		question += " [y/N]? "
	selected = None
	while type(selected) != bool:
		selected = raw_input(question).strip().lower()
		if selected == "":
			selected = default
		elif selected in ("y", "yes"):
			selected = True
		elif selected in ("n", "no"):
			selected = False
		else:
			print "Please answer the question with yes or no."
	return selected

def yes_edit_no_question(question, default):
	assert default in ("yes", "edit", "no")
	if default == "yes":
		question += " [Y/e/n]? "
	elif default == "edit":
		question += " [y/E/n]? "
	else:
		question += " [y/e/N]? "
	selected = None
	while selected not in ("yes", "edit", "no"):
		selected = raw_input(question).strip().lower()
		if selected == "":
			selected = default
		elif selected in ("y", "yes"):
			selected = "yes"
		elif selected in ("e", "edit"):
			selected = "edit"
		elif selected in ("n", "no"):
			selected = "no"
		else:
			print "Please answer the question with yes, edit, or no."
	return selected

def edit_source():
	# Spawn shell to allow modifications
	cmd = [get_user_shell()]
	Print.command(cmd)
	print """An interactive shell in file://%s was launched.
Edit your files. When you are done, exit the shell. If you wish to abort the
process, exit the shell such that it returns an exit code other than zero.""" % \
			(os.getcwd())
	returncode = subprocess.call(cmd)
	if returncode != 0:
		Print.error("Shell exited with exit value %i." % (returncode))
		sys.exit(1)

def get_fixed_lauchpad_bugs(changes_file):
	assert os.path.isfile(changes_file), "%s does not exist." % (changes_file)
	changes = debian.deb822.Changes(file(changes_file))
	fixed_bugs = []
	if "Launchpad-Bugs-Fixed" in changes:
		fixed_bugs = changes["Launchpad-Bugs-Fixed"].split(" ")
	fixed_bugs = map(int, fixed_bugs)
	return fixed_bugs

def strip_epoch(version):
	'''Removes the epoch from a Debian version string.

	strip_epoch(1:1.52-1) will return "1.52-1" and strip_epoch(1.1.3-1) will
	return "1.1.3-1".'''

	parts = version.full_version.split(':')
	if len(parts) > 1:
		del parts[0]
	version_without_epoch = ':'.join(parts)
	return version_without_epoch

def ask_for_manual_fixing():
	if not boolean_question("Do you want to resolve this issue manually", True):
		print "Abort."
		sys.exit(USER_ABORT)

def get_patch_or_branch(bug):
	patch = None
	branch = None
	attached_patches = filter(lambda a: a.type == "Patch", bug.attachments)
	linked_branches = map(lambda b: b.branch, bug.linked_branches)
	if len(attached_patches) == 0 and len(linked_branches) == 0:
		if len(bug.attachments) == 0:
			Print.error("No attachment and no linked branch found on bug #%i." % \
					(bug.id))
		else:
			Print.error(("No attached patch and no linked branch found. Go to"
					" https://launchpad.net/bugs/%i and mark an attachment as"
					" patch.") % (bug.id))
		sys.exit(1)
	elif len(attached_patches) == 1 and len(linked_branches) == 0:
		patch = attached_patches[0]
	elif len(attached_patches) == 0 and len(linked_branches) == 1:
		branch = linked_branches[0].bzr_identity
	else:
		if len(attached_patches) == 0:
			Print.normal("https://launchpad.net/bugs/%i has %i branches linked:" % \
					(bug.id, len(linked_branches)))
		elif len(linked_branches) == 0:
			Print.normal("https://launchpad.net/bugs/%i has %i patches attached:" % \
					(bug.id, len(attached_patches)))
		else:
			Print.normal("https://launchpad.net/bugs/%i has %i branch(es) linked and %i patch(es) attached:" % \
					(bug.id, len(linked_branches), len(attached_patches)))
		i = 0
		for linked_branch in linked_branches:
			i += 1
			print "%i) %s" % (i, linked_branch.display_name)
		for attached_patch in attached_patches:
			i += 1
			print "%i) %s" % (i, attached_patch.title)
		selected = input_number("Which branch or patch do you want to download",
				1, i, i)
		if selected <= len(linked_branches):
			branch = linked_branches[selected - 1].bzr_identity
		else:
			patch = attached_patches[selected - len(linked_branches) - 1]
	return (patch, branch)

def download_patch(patch):
	patch_file = re.sub(" ", "_", patch.title)
	if not reduce(lambda r, x: r or patch.title.endswith(x), (".debdiff", ".diff", ".patch"), False):
		Print.info("Patch %s does not have a proper file extension." % (patch.title))
		patch_file += ".patch"

	Print.info("Downloading %s." % (patch_file))
	f = open(patch_file, "w")
	f.write(patch.data.open().read())
	f.close()
	return Patch(patch_file)

def download_branch(branch):
	dir_name = os.path.basename(branch)
	if os.path.isdir(dir_name):
		shutil.rmtree(dir_name)
	cmd = ["bzr", "branch", branch]
	Print.command(cmd)
	if subprocess.call(cmd) != 0:
		Print.error("Failed to download branch %s." % (branch))
		sys.exit(1)
	return dir_name

def merge_branch(branch):
	edit = False
	cmd = ["bzr", "merge", branch]
	Print.command(cmd)
	if subprocess.call(cmd) != 0:
		Print.error("Failed to merge branch %s." % (branch))
		ask_for_manual_fixing()
		edit = True
	return edit

def extract_source(dsc_file, verbose=False):
	cmd = ["dpkg-source", "-x", dsc_file]
	if not verbose:
		cmd.insert(1, "-q")
	Print.command(cmd)
	if subprocess.call(cmd) != 0:
		Print.error("Extraction of %s failed." % (os.path.basename(dsc_file)))
		sys.exit(1)

def apply_patch(task, patch):
	edit = False
	if patch.is_debdiff():
		cmd = ["patch", "--merge", "--force", "-p", str(patch.get_strip_level()),
				"-i", patch.full_path]
		Print.command(cmd)
		if subprocess.call(cmd) != 0:
			Print.error("Failed to apply debdiff %s to %s %s." % \
					(patch.get_name(), task.package, task.get_version()))
			if not edit:
				ask_for_manual_fixing()
				edit = True
	else:
		# FIXME: edit-patch needs a non-interactive mode
		# https://launchpad.net/bugs/612566
		cmd = ["edit-patch", patch.full_path]
		Print.command(cmd)
		if subprocess.call(cmd) != 0:
			Print.error("Failed to apply diff %s to %s %s." % \
					(patch.get_name(), task.package, task.get_version()))
			if not edit:
				ask_for_manual_fixing()
				edit = True
	return edit

def main(script_name, bug_number, build, edit, keyid, upload, verbose=False):
	if "SPONSOR_PATCH_WORKDIR" in os.environ:
		# FIXME: add command line parameter
		workdir = os.path.abspath(os.environ["SPONSOR_PATCH_WORKDIR"])
		if not os.path.isdir(workdir):
			os.makedirs(workdir)
			# FIXME: Print nice error message on failure
		Print.command(["cd", workdir])
		os.chdir(workdir)
	else:
		workdir = os.getcwd()

	script_name = os.path.basename(sys.argv[0])
	launchpad = launchpadlib.launchpad.Launchpad.login_anonymously(script_name, "production")
	bug = launchpad.bugs[bug_number]

	(patch, branch) = get_patch_or_branch(bug)

	bug_tasks = map(lambda x: BugTask(x, launchpad), bug.bug_tasks)
	ubuntu_tasks = filter(lambda x: x.is_ubuntu_task(), bug_tasks)
	if len(ubuntu_tasks) == 0:
		Print.error("No Ubuntu bug task found on bug #%i." % (bug_number))
		sys.exit(1)
	elif len(ubuntu_tasks) == 1:
		task = ubuntu_tasks[0]
	if len(ubuntu_tasks) > 1:
		if verbose:
			Print.info("%i Ubuntu tasks exist for bug #%i." % \
					(len(ubuntu_tasks), bug_number))
			for task in ubuntu_tasks:
				print task.get_short_info()
		open_ubuntu_tasks = filter(lambda x: not x.is_complete(), ubuntu_tasks)
		if len(open_ubuntu_tasks) == 1:
			task = open_ubuntu_tasks[0]
		else:
			Print.normal("https://launchpad.net/bugs/%i has %i Ubuntu tasks:" % \
					(bug_number, len(ubuntu_tasks)))
			for i in xrange(len(ubuntu_tasks)):
				print "%i) %s" % (i + 1, ubuntu_tasks[i].get_package_and_series())
			selected = input_number("To which Ubuntu tasks do the patch belong",
					1, len(ubuntu_tasks))
			task = ubuntu_tasks[selected - 1]
	Print.info("Selected Ubuntu task: %s" % (task.get_short_info()))

	dsc_file = task.download_source()
	assert os.path.isfile(dsc_file), "%s does not exist." % (dsc_file)

	if patch:
		patch = download_patch(patch)

		Print.info("Ubuntu package: %s" % (task.package))
		if task.is_merge():
			Print.info("The task is a merge request.")

		extract_source(dsc_file, verbose)

		# change directory
		directory = task.package + '-' + task.get_version().upstream_version
		Print.command(["cd", directory])
		os.chdir(directory)

		edit |= apply_patch(task, patch)
	elif branch:
		branch_dir = download_branch(task.get_branch_link())

		# change directory
		Print.command(["cd", branch_dir])
		os.chdir(branch_dir)

		edit |= merge_branch(branch)

	while True:
		if edit:
			edit_source()
		# All following loop executions require manual editing.
		edit = True

		# update the Maintainer field
		cmd = ["update-maintainer"]
		if not verbose:
			cmd.append("-q")
		Print.command(cmd)
		subprocess.check_call(cmd)

		# Get new version of package
		changelog = debian.changelog.Changelog(file("debian/changelog"))
		try:
			new_version = changelog.get_version()
		except IndexError:
			Print.error("Debian package version could not be determined. debian/changelog is probably malformed.")
			ask_for_manual_fixing()
			continue

		# Check if version of the new package is greater than the version in the archive.
		if new_version <= task.get_version():
			Print.error("The version %s is not greater than the already available %s." % \
					(new_version, task.get_version()))
			ask_for_manual_fixing()
			continue

		cmd = ["dch", "--maintmaint", "--edit", ""]
		Print.command(cmd)
		if subprocess.call(cmd) != 0:
			Print.info("Failed to update timetamp in debian/changelog.")

		# Build source package
		if patch:
			cmd = ['debuild', '--no-lintian', '-S']
		elif branch:
			cmd = ['bzr', 'bd', '-S', '--', '--no-lintian']
		previous_version = task.get_previous_version()
		cmd.append("-v" + previous_version.full_version)
		if previous_version.upstream_version == changelog.upstream_version \
				and upload == "ubuntu":
			cmd.append("-sd")
		else:
			cmd.append("-sa")
		if not keyid is None:
			cmd += ["-k" + keyid]
		env = os.environ
		if upload == 'ubuntu':
			env['DEB_VENDOR'] = 'Ubuntu'
		Print.command(cmd)
		if subprocess.call(cmd, env=env) != 0:
			Print.error("Failed to build source tarball.")
			# TODO: Add a "retry" option
			ask_for_manual_fixing()
			continue

		# Generate debdiff
		new_dsc_file = os.path.join(workdir,
				task.package + "_" + strip_epoch(new_version) + ".dsc")
		assert os.path.isfile(dsc_file), "%s does not exist." % (dsc_file)
		assert os.path.isfile(new_dsc_file), "%s does not exist." % (new_dsc_file)
		cmd = ["debdiff", dsc_file, new_dsc_file]
		debdiff_file = os.path.join(workdir,
				task.package + "_" + strip_epoch(new_version) + ".debdiff")
		if not verbose:
			cmd.insert(1, "-q")
		Print.command(cmd + [">", debdiff_file])
		debdiff = subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()[0]

		# write debdiff file
		f = open(debdiff_file, "w")
		f.writelines(debdiff)
		f.close()

		# Make sure that the Launchpad bug will be closed
		changes_file = new_dsc_file[:-4] + "_source.changes"
		if bug_number not in get_fixed_lauchpad_bugs(changes_file):
			Print.error("Launchpad bug #%i is not closed by new version." % \
					(bug_number))
			ask_for_manual_fixing()
			continue

		ubuntu = launchpad.distributions['ubuntu']
		devel_series = ubuntu.current_series.name
		supported_series = [series.name for series in ubuntu.series
				if series.active and series.name != devel_series]
		# Make sure that the target is correct
		if upload == "ubuntu":
			allowed = map(lambda s: s + "-proposed", supported_series) + \
					[devel_series]
			if changelog.distributions not in allowed:
				Print.error("%s is not an allowed series. It needs to be one of %s." \
						% (changelog.distributions, ", ".join(allowed)))
				ask_for_manual_fixing()
				continue
		elif upload and upload.startwith("ppa/"):
			allowed = supported_series + [devel_series]
			if changelog.distributions not in allowed:
				Print.error("%s is not an allowed series. It needs to be one of %s." \
						% (changelog.distributions, ", ".join(allowed)))
				ask_for_manual_fixing()
				continue

		if build:
			buildresult = os.path.join(workdir, task.package + "-buildresult")
			if not os.path.isdir(buildresult):
				os.makedirs(buildresult)
			cmd = ["dpkg-architecture", "-qDEB_BUILD_ARCH_CPU"]
			architecture = subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()[0].strip()

			# build package
			dist = re.sub("-.*$", "", changelog.distributions)
			# TODO: Do not rely on a specific pbuilder configuration.
			cmd = ["sudo", "-E", "DIST=" + dist, "pbuilder", "--build",
					"--distribution", dist, "--buildresult", buildresult,
					"--architecture", architecture, new_dsc_file]
			Print.command(cmd)
			if subprocess.call(cmd) != 0:
				Print.error("Failed to build %s from source." % \
						(os.path.basename(new_dsc_file)))
				# TODO: Add "retry" and "update" option
				ask_for_manual_fixing()
				continue

			# Check lintian
			build_changes = os.path.join(buildresult, task.package + "_" + \
					strip_epoch(new_version) + "_" + architecture + ".changes")
			assert os.path.isfile(build_changes), "%s does not exist." % (build_changes)
			cmd = ["lintian", "-IE", "--pedantic", "-q", build_changes]
			lintian_file = os.path.join(workdir,
					task.package + "_" + strip_epoch(new_version) + ".lintian")
			Print.command(cmd + [">", lintian_file])
			report = subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()[0]

			# write lintian report file
			f = open(lintian_file, "w")
			f.writelines(report)
			f.close()

		# Upload package
		if upload:
			if upload == "ubuntu":
				build_log = os.path.join(buildresult, task.package + "_" + \
						strip_epoch(new_version) + "_" + architecture + ".build")
				print "Please check %s %s carefully:\nfile://%s\nfile://%s\nfile://%s" % \
						(task.package, new_version, debdiff_file, lintian_file, build_log)
				answer = yes_edit_no_question("Do you want to upload the package to the official Ubuntu archive", "yes")
				if answer == "edit":
					continue
				elif answer == "no":
					print "Abort."
					sys.exit(USER_ABORT)
				cmd = ["dput", "--force", upload, changes_file]
				Print.command(cmd)
				if subprocess.call(cmd) != 0:
					Print.error("Upload of %s to %s failed." % \
							(os.path.basename(changes_file), upload))
					sys.exit(1)

		# Leave while loop if everything worked
		break

if __name__ == "__main__":
	script_name = os.path.basename(sys.argv[0])
	usage = "%s [options] <bug number>" % (script_name)
	epilog = "See %s(1) for more info." % (script_name)
	parser = optparse.OptionParser(usage=usage, epilog=epilog)

	parser.add_option("-b", "--build", help="Build the package with pbuilder.",
			dest="build", action="store_true", default=False)
	parser.add_option("-e", "--edit", help="launch sub-shell to allow editing of the patch",
			dest="edit", action="store_true", default=False)
	parser.add_option("-k", "--key", dest="keyid",
			help="Specify the key ID to be used for signing.", default=None)
	parser.add_option("-s", "--sponsor", help="sponsoring; equals -b -u ubuntu",
			dest="sponsoring", action="store_true", default=False)
	parser.add_option("-u", "--upload", dest="upload",
			help="Specify an upload destination (default none).", default=None)
	parser.add_option("-v", "--verbose", help="print more information",
			dest="verbose", action="store_true", default=False)

	(options, args) = parser.parse_args()
	Print.set_verbosity(options.verbose)

	if len(args) == 0:
		Print.error("No bug number specified.")
		sys.exit(1)
	elif len(args) > 1:
		Print.error("Multiple bug numbers specified: %s" % (", ".join(args)))
		sys.exit(1)

	bug_number = args[0]
	if bug_number.isdigit():
		bug_number = int(bug_number)
	else:
		Print.error("Invalid bug number specified: %s" % (bug_number))
		sys.exit(1)

	if options.sponsoring:
		options.build = True
		options.upload = "ubuntu"

	main(script_name, bug_number, options.build, options.edit, options.keyid,
			options.upload, options.verbose)

# vim: set noet: