# -*- coding: utf-8 -*-
#
#   common.py - common methods used by requestsync
#
#   Copyright © 2009 Michael Bienia <geser@ubuntu.com>
#
#   This module may contain code written by other authors/contributors to
#   the main requestsync script. See there for their names.
#
#   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; version 2
# 
#   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.
#
#   Please see the /usr/share/common-licenses/GPL-2 file for the full text
#   of the GNU General Public License license.

import os
import sys
import urllib2
import re
import tempfile
import subprocess
from debian.changelog import Changelog

def raw_input_exit_on_ctrlc(*args, **kwargs):
	'''
	A wrapper around raw_input() to exit with a normalized message on Control-C
	'''
	try:
		return raw_input(*args, **kwargs)
	except KeyboardInterrupt:
		print '\nAbort requested. No sync request filed.'
		sys.exit(1)

def getDebianChangelog(srcpkg, version):
	'''
	Return the new changelog entries upto 'version'.
	'''
	pkgname = srcpkg.getPackageName()
	pkgversion = srcpkg.getVersion()
	component = srcpkg.getComponent()
	if pkgname.startswith('lib'):
		subdir = 'lib%s' % pkgname[3]
	else:
		subdir = pkgname[0]
	# Strip epoch from version
	if ':' in pkgversion:
		pkgversion = pkgversion[pkgversion.find(':')+1:]

	# Get the debian changelog file from packages.debian.org
	try:
		changelog = urllib2.urlopen(
			'http://packages.debian.org/changelogs/pool/%s/%s/%s/%s_%s/changelog.txt' % \
			(component, subdir, pkgname, pkgname, pkgversion))
	except urllib2.HTTPError, error:
		print >> sys.stderr, 'Unable to connect to packages.debian.org: %s' % error
		return None

	new_entries = ''
	changelog = Changelog(changelog.read())
	for block in changelog:
		if block.version > version:
			# see also Debian #561805
			new_entries += unicode(str(block).decode('utf-8'))

	return new_entries

def edit_report(subject, body, changes_required = False):
	'''
	Ask if the user wants to edit a report (consisting of subject and body)
	in sensible-editor.

	If changes_required is True then the file has to be edited before we
	can proceed.

	Returns (new_subject, new_body).
	'''

	editing_finished = False
	while not editing_finished:
		report = 'Summary (one line):\n%s\n\nDescription:\n%s' % (subject, body)

		if not changes_required:
			print 'Currently the report looks as follows:\n%s' % report
			while True:
				val = raw_input_exit_on_ctrlc('Do you want to edit the report [y/N]? ')
				if val.lower() in ('y', 'yes'):
					break
				elif val.lower() in ('n', 'no', ''):
					editing_finished = True
					break
				else:
					print 'Invalid answer.'

		if not editing_finished:
			# Create tempfile and remember mtime
			report_file = tempfile.NamedTemporaryFile(prefix='requestsync_')
			report_file.write(report.encode('utf-8'))
			report_file.flush()
			mtime_before = os.stat(report_file.name).st_mtime

			# Launch editor
			try:
				subprocess.check_call(['sensible-editor', report_file.name])
			except subprocess.CalledProcessError, e:
				print >> sys.stderr, 'Error calling sensible-editor: %s\nAborting.' % e
				sys.exit(1)

			# Check if the tempfile has been changed
			if changes_required:
				if mtime_before == os.stat(report_file.name).st_mtime:
					print 'The report has not been changed, but you have to explain why ' \
						'the Ubuntu changes can be dropped.'
					raw_input_exit_on_ctrlc('Press [Enter] to retry or [Control-C] to abort. ')
				else:
					changes_required = False

			report_file.seek(0)
			report = report_file.read().decode('utf-8')
			report_file.close()

			# Undecorate report again
			(subject, body) = report.split("\nDescription:\n", 1)
			# Remove prefix and whitespace from subject
			subject = re.sub('^Summary \(one line\):\s*', '', subject, 1).strip()

	return (subject, body)