# -*- coding: utf-8 -*-

"""

    rhodecode.controllers.changeset

    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    changeset controller for pylons showoing changes beetween

    revisions

    :created_on: Apr 25, 2010

    :author: marcink

    :copyright: (C) 2009-2011 Marcin Kuzminski <marcin@python-works.com>

    :license: GPLv3, see COPYING for more details.

"""

# 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 logging

import traceback

from pylons import tmpl_context as c, url, request, response

from pylons.i18n.translation import _

from pylons.controllers.util import redirect

from pylons.decorators import jsonify

import rhodecode.lib.helpers as h

from rhodecode.lib.auth import LoginRequired, HasRepoPermissionAnyDecorator, \

    NotAnonymous

from rhodecode.lib.base import BaseRepoController, render

from rhodecode.lib.utils import EmptyChangeset

from rhodecode.lib.compat import OrderedDict

from rhodecode.model.db import ChangesetComment

from rhodecode.model.comment import ChangesetCommentsModel

from vcs.exceptions import RepositoryError, ChangesetError, \

    ChangesetDoesNotExistError

from vcs.nodes import FileNode

from vcs.utils import diffs as differ

from webob.exc import HTTPForbidden

log = logging.getLogger(__name__)

class ChangesetController(BaseRepoController):

    @LoginRequired()

    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',

                                   'repository.admin')

    def __before__(self):

        super(ChangesetController, self).__before__()

        c.affected_files_cut_off = 60

    def index(self, revision):

        def wrap_to_table(str):

            return '''<table class="code-difftable">

                        <tr class="line">

                        <td class="lineno new"></td>

                        <td class="code"><pre>%s</pre></td>

                        </tr>

                      </table>''' % str

        #get ranges of revisions if preset

        rev_range = revision.split('...')[:2]

        try:

            if len(rev_range) == 2:

                rev_start = rev_range[0]

                rev_end = rev_range[1]

                rev_ranges = c.rhodecode_repo.get_changesets(start=rev_start,

                                                            end=rev_end)

            else:

                rev_ranges = [c.rhodecode_repo.get_changeset(revision)]

            c.cs_ranges = list(rev_ranges)

            if not c.cs_ranges:

                raise RepositoryError('Changeset range returned empty result')

        except (RepositoryError, ChangesetDoesNotExistError, Exception), e:

            log.error(traceback.format_exc())

            h.flash(str(e), category='warning')

            return redirect(url('home'))

        c.changes = OrderedDict()

        c.sum_added = 0

        c.sum_removed = 0

        c.lines_added = 0

        c.lines_deleted = 0

        c.cut_off = False  # defines if cut off limit is reached

        c.comments = []

        # Iterate over ranges (default changeset view is always one changeset)

        for changeset in c.cs_ranges:

            c.comments.extend(ChangesetCommentsModel()\

                              .get_comments(c.rhodecode_db_repo.repo_id,

                                            changeset.raw_id))

            c.changes[changeset.raw_id] = []

            try:

                changeset_parent = changeset.parents[0]

            except IndexError:

                changeset_parent = None

            #==================================================================

            # ADDED FILES

            #==================================================================

            for node in changeset.added:

                filenode_old = FileNode(node.path, '', EmptyChangeset())

                if filenode_old.is_binary or node.is_binary:

                    diff = wrap_to_table(_('binary file'))

                    st = (0, 0)

                else:

                    # in this case node.size is good parameter since those are

                    # added nodes and their size defines how many changes were

                    # made

                    c.sum_added += node.size

                    if c.sum_added < self.cut_off_limit:

                        f_gitdiff = differ.get_gitdiff(filenode_old, node)

                        d = differ.DiffProcessor(f_gitdiff, format='gitdiff')

                        st = d.stat()

                        diff = d.as_html()

                    else:

                        diff = wrap_to_table(_('Changeset is to big and '

                                               'was cut off, see raw '

                                               'changeset instead'))

                        c.cut_off = True

                        break

                cs1 = None

                cs2 = node.last_changeset.raw_id

                c.lines_added += st[0]

                c.lines_deleted += st[1]

                c.changes[changeset.raw_id].append(('added', node, diff,

                                                    cs1, cs2, st))

            #==================================================================

            # CHANGED FILES

            #==================================================================

            if not c.cut_off:

                for node in changeset.changed:

                    try:

                        filenode_old = changeset_parent.get_node(node.path)

                    except ChangesetError:

                        log.warning('Unable to fetch parent node for diff')

                        filenode_old = FileNode(node.path, '',

                                                EmptyChangeset())

                    if filenode_old.is_binary or node.is_binary:

                        diff = wrap_to_table(_('binary file'))

                        st = (0, 0)

                    else:

                        if c.sum_removed < self.cut_off_limit:

                            f_gitdiff = differ.get_gitdiff(filenode_old, node)

                            d = differ.DiffProcessor(f_gitdiff,

                                                     format='gitdiff')

                            st = d.stat()

                            if (st[0] + st[1]) * 256 > self.cut_off_limit:

                                diff = wrap_to_table(_('Diff is to big '

                                                       'and was cut off, see '

                                                       'raw diff instead'))

                            else:

                                diff = d.as_html()

                            if diff:

                                c.sum_removed += len(diff)

                        else:

                            diff = wrap_to_table(_('Changeset is to big and '

                                                   'was cut off, see raw '

                                                   'changeset instead'))

                            c.cut_off = True

                            break

                    cs1 = filenode_old.last_changeset.raw_id

                    cs2 = node.last_changeset.raw_id

                    c.lines_added += st[0]

                    c.lines_deleted += st[1]

                    c.changes[changeset.raw_id].append(('changed', node, diff,

                                                        cs1, cs2, st))

            #==================================================================

            # REMOVED FILES

            #==================================================================

            if not c.cut_off:

                for node in changeset.removed:

                    c.changes[changeset.raw_id].append(('removed', node, None,

                                                        None, None, (0, 0)))

        if len(c.cs_ranges) == 1:

            c.changeset = c.cs_ranges[0]

            c.changes = c.changes[c.changeset.raw_id]

            return render('changeset/changeset.html')

        else:

            return render('changeset/changeset_range.html')

    def raw_changeset(self, revision):

        method = request.GET.get('diff', 'show')

        try:

            c.scm_type = c.rhodecode_repo.alias

            c.changeset = c.rhodecode_repo.get_changeset(revision)

        except RepositoryError:

            log.error(traceback.format_exc())

            return redirect(url('home'))

        else:

            try:

                c.changeset_parent = c.changeset.parents[0]

            except IndexError:

                c.changeset_parent = None

            c.changes = []

            for node in c.changeset.added:

                filenode_old = FileNode(node.path, '')

                if filenode_old.is_binary or node.is_binary:

                    diff = _('binary file') + '\n'

                else:

                    f_gitdiff = differ.get_gitdiff(filenode_old, node)

                    diff = differ.DiffProcessor(f_gitdiff,

                                                format='gitdiff').raw_diff()

                cs1 = None

                cs2 = node.last_changeset.raw_id

                c.changes.append(('added', node, diff, cs1, cs2))

            for node in c.changeset.changed:

                filenode_old = c.changeset_parent.get_node(node.path)

                if filenode_old.is_binary or node.is_binary:

                    diff = _('binary file')

                else:

                    f_gitdiff = differ.get_gitdiff(filenode_old, node)

                    diff = differ.DiffProcessor(f_gitdiff,

                                                format='gitdiff').raw_diff()

                cs1 = filenode_old.last_changeset.raw_id

                cs2 = node.last_changeset.raw_id

                c.changes.append(('changed', node, diff, cs1, cs2))

        response.content_type = 'text/plain'

        if method == 'download':

            response.content_disposition = 'attachment; filename=%s.patch' \

                                            % revision

        c.parent_tmpl = ''.join(['# Parent  %s\n' % x.raw_id for x in

                                                 c.changeset.parents])

        c.diffs = ''

        for x in c.changes:

            c.diffs += x[2]

        return render('changeset/raw_changeset.html')

    def comment(self, repo_name, revision):

        ccmodel = ChangesetCommentsModel()

        ccmodel.create(text=request.POST.get('text'),

        return redirect(h.url('changeset_home', repo_name=repo_name,

                              revision=revision))

    @jsonify

    def delete_comment(self, comment_id):

        co = ChangesetComment.get(comment_id)

        if (h.HasPermissionAny('hg.admin', 'repository.admin')() or

            co.author.user_id == c.rhodecode_user.user_id):

            ccmodel = ChangesetCommentsModel()

            ccmodel.delete(comment_id=comment_id)

            return True

        else:

            raise HTTPForbidden()

"""Helper functions

Consists of functions to typically be used within templates, but also

available to Controllers. This module is available to both as 'h'.

"""

import random

import hashlib

import StringIO

import urllib

import math

from datetime import datetime

from pygments.formatters import HtmlFormatter

from pygments import highlight as code_highlight

from pylons import url, request, config

from pylons.i18n.translation import _, ungettext

from webhelpers.html import literal, HTML, escape

from webhelpers.html.tools import *

from webhelpers.html.builder import make_tag

from webhelpers.html.tags import auto_discovery_link, checkbox, css_classes, \

    end_form, file, form, hidden, image, javascript_link, link_to, link_to_if, \

    link_to_unless, ol, required_legend, select, stylesheet_link, submit, text, \

    password, textarea, title, ul, xml_declaration, radio

from webhelpers.html.tools import auto_link, button_to, highlight, js_obfuscate, \

    mail_to, strip_links, strip_tags, tag_re

from webhelpers.number import format_byte_size, format_bit_size

from webhelpers.pylonslib import Flash as _Flash

from webhelpers.pylonslib.secure_form import secure_form

from webhelpers.text import chop_at, collapse, convert_accented_entities, \

    convert_misc_entities, lchop, plural, rchop, remove_formatting, \

    replace_whitespace, urlify, truncate, wrap_paragraphs

from webhelpers.date import time_ago_in_words

from webhelpers.paginate import Page

from webhelpers.html.tags import _set_input_attrs, _set_id_attr, \

from vcs.utils.annotate import annotate_highlight

from rhodecode.lib.utils import repo_name_slug

from rhodecode.lib import str2bool, safe_unicode, safe_str, get_changeset_safe

from rhodecode.lib.markup_renderer import MarkupRenderer

def _reset(name, value=None, id=NotGiven, type="reset", **attrs):

    """

    Reset button

    """

    _set_input_attrs(attrs, type, name, value)

    _set_id_attr(attrs, id, name)

    convert_boolean_attrs(attrs, ["disabled"])

    return HTML.input(**attrs)

reset = _reset

def get_token():

    """Return the current authentication token, creating one if one doesn't

    already exist.

    """

    token_key = "_authentication_token"

    from pylons import session

    if not token_key in session:

        try:

            token = hashlib.sha1(str(random.getrandbits(128))).hexdigest()

        except AttributeError: # Python < 2.4

            token = hashlib.sha1(str(random.randrange(2 ** 128))).hexdigest()

        session[token_key] = token

        if hasattr(session, 'save'):

            session.save()

    return session[token_key]

class _GetError(object):

    """Get error from form_errors, and represent it as span wrapped error

    message

    :param field_name: field to fetch errors for

    :param form_errors: form errors dict

    """

    def __call__(self, field_name, form_errors):

        tmpl = """<span class="error_msg">%s</span>"""

        if form_errors and form_errors.has_key(field_name):

            return literal(tmpl % form_errors.get(field_name))

get_error = _GetError()

class _ToolTip(object):

    def __call__(self, tooltip_title, trim_at=50):

        """Special function just to wrap our text into nice formatted

        autowrapped text

        :param tooltip_title:

        """

        return escape(tooltip_title)

tooltip = _ToolTip()

class _FilesBreadCrumbs(object):

    def __call__(self, repo_name, rev, paths):

        if isinstance(paths, str):

            paths = safe_unicode(paths)

        url_l = [link_to(repo_name, url('files_home',

                                        repo_name=repo_name,

                                        revision=rev, f_path=''))]

        paths_l = paths.split('/')

        for cnt, p in enumerate(paths_l):

            if p != '':

                url_l.append(link_to(p, url('files_home',

                                            repo_name=repo_name,

                                            revision=rev,

                                            f_path='/'.join(paths_l[:cnt + 1]))))

        return literal('/'.join(url_l))

files_breadcrumbs = _FilesBreadCrumbs()

class CodeHtmlFormatter(HtmlFormatter):

    """My code Html Formatter for source codes

    """

    def wrap(self, source, outfile):

        return self._wrap_div(self._wrap_pre(self._wrap_code(source)))

    def _wrap_code(self, source):

        for cnt, it in enumerate(source):

            i, t = it

            t = '<div id="L%s">%s</div>' % (cnt + 1, t)

            yield i, t

    def _wrap_tablelinenos(self, inner):

        dummyoutfile = StringIO.StringIO()

        lncount = 0

        for t, line in inner:

            if t:

                lncount += 1

            dummyoutfile.write(line)

        fl = self.linenostart

        mw = len(str(lncount + fl - 1))

        sp = self.linenospecial

        st = self.linenostep

        la = self.lineanchors

        aln = self.anchorlinenos

        nocls = self.noclasses

        if sp:

            lines = []

            for i in range(fl, fl + lncount):

                if i % st == 0:

                    if i % sp == 0:

                        if aln:

                            lines.append('<a href="#%s%d" class="special">%*d</a>' %

                                         (la, i, mw, i))

                        else:

                            lines.append('<span class="special">%*d</span>' % (mw, i))

                    else:

                        if aln:

                            lines.append('<a href="#%s%d">%*d</a>' % (la, i, mw, i))

                        else:

                            lines.append('%*d' % (mw, i))

                else:

                    lines.append('')

            ls = '\n'.join(lines)

        else:

            lines = []

            for i in range(fl, fl + lncount):

                if i % st == 0:

                    if aln:

                        lines.append('<a href="#%s%d">%*d</a>' % (la, i, mw, i))

                    else:

                        lines.append('%*d' % (mw, i))

                else:

                    lines.append('')

            ls = '\n'.join(lines)

        # in case you wonder about the seemingly redundant <div> here: since the

        # content in the other cell also is wrapped in a div, some browsers in

        # some configurations seem to mess up the formatting...

        if nocls:

            yield 0, ('<table class="%stable">' % self.cssclass +

                      '<tr><td><div class="linenodiv" '

                      'style="background-color: #f0f0f0; padding-right: 10px">'

                      '<pre style="line-height: 125%">' +

                      ls + '</pre></div></td><td id="hlcode" class="code">')

        else:

            yield 0, ('<table class="%stable">' % self.cssclass +

                      '<tr><td class="linenos"><div class="linenodiv"><pre>' +

                      ls + '</pre></div></td><td id="hlcode" class="code">')

        yield 0, dummyoutfile.getvalue()

        yield 0, '</td></tr></table>'

def pygmentize(filenode, **kwargs):

    """pygmentize function using pygments

    :param filenode:

    """

    return literal(code_highlight(filenode.content,

                                  filenode.lexer, CodeHtmlFormatter(**kwargs)))

def pygmentize_annotation(repo_name, filenode, **kwargs):

    """pygmentize function for annotation

    :param filenode:

    """

    color_dict = {}

    def gen_color(n=10000):

        """generator for getting n of evenly distributed colors using

        hsv color and golden ratio. It always return same order of colors

        :returns: RGB tuple

        """

        def hsv_to_rgb(h, s, v):

            if s == 0.0: return v, v, v

            i = int(h * 6.0) # XXX assume int() truncates!

            f = (h * 6.0) - i

            p = v * (1.0 - s)

            q = v * (1.0 - s * f)

            t = v * (1.0 - s * (1.0 - f))

            i = i % 6

            if i == 0: return v, t, p

            if i == 1: return q, v, p

            if i == 2: return p, v, t

            if i == 3: return p, q, v

            if i == 4: return t, p, v

            if i == 5: return v, p, q

        golden_ratio = 0.618033988749895

        h = 0.22717784590367374

        for _ in xrange(n):

            h += golden_ratio

            h %= 1

            HSV_tuple = [h, 0.95, 0.95]

            RGB_tuple = hsv_to_rgb(*HSV_tuple)

            yield map(lambda x:str(int(x * 256)), RGB_tuple)

    cgenerator = gen_color()

    def get_color_string(cs):

        if color_dict.has_key(cs):

            col = color_dict[cs]

        else:

            col = color_dict[cs] = cgenerator.next()

        return "color: rgb(%s)! important;" % (', '.join(col))

    def url_func(repo_name):

        def _url_func(changeset):

            author = changeset.author

            date = changeset.date

            message = tooltip(changeset.message)

            tooltip_html = ("<div style='font-size:0.8em'><b>Author:</b>"

                            " %s<br/><b>Date:</b> %s</b><br/><b>Message:"

                            "</b> %s<br/></div>")

            tooltip_html = tooltip_html % (author, date, message)

            lnk_format = '%5s:%s' % ('r%s' % changeset.revision,

                                     short_id(changeset.raw_id))

            uri = link_to(

                    lnk_format,

                    url('changeset_home', repo_name=repo_name,

                        revision=changeset.raw_id),

                    style=get_color_string(changeset.raw_id),

                    class_='tooltip',

                    title=tooltip_html

                  )

            uri += '\n'

            return uri

        return _url_func

    return literal(annotate_highlight(filenode, url_func(repo_name), **kwargs))

def is_following_repo(repo_name, user_id):

    from rhodecode.model.scm import ScmModel

    return ScmModel().is_following_repo(repo_name, user_id)

flash = _Flash()

#==============================================================================

# SCM FILTERS available via h.

#==============================================================================

from vcs.utils import author_name, author_email

from rhodecode.lib import credentials_filter, age as _age

age = lambda  x:_age(x)

capitalize = lambda x: x.capitalize()

email = author_email

email_or_none = lambda x: email(x) if email(x) != x else None

person = lambda x: author_name(x)

short_id = lambda x: x[:12]

hide_credentials = lambda x: ''.join(credentials_filter(x))

def bool2icon(value):

    """Returns True/False values represented as small html image of true/false

    icons

    :param value: bool value

    """

    if value is True:

        return HTML.tag('img', src=url("/images/icons/accept.png"),

                        alt=_('True'))

    if value is False:

        return HTML.tag('img', src=url("/images/icons/cancel.png"),

                        alt=_('False'))

    return value

def action_parser(user_log, feed=False):

    """This helper will action_map the specified string action into translated

    fancy names with icons and links

    :param user_log: user log instance

    :param feed: use output for feeds (no html and fancy icons)

    """

    action = user_log.action

    action_params = ' '

    x = action.split(':')

    if len(x) > 1:

        action, action_params = x

    def get_cs_links():

        revs_limit = 3 #display this amount always

        revs_top_limit = 50 #show upto this amount of changesets hidden

        revs = action_params.split(',')

        repo_name = user_log.repository.repo_name

        from rhodecode.model.scm import ScmModel

        repo = user_log.repository.scm_instance

        message = lambda rev: get_changeset_safe(repo, rev).message

        cs_links = []

        cs_links.append(" " + ', '.join ([link_to(rev,

                url('changeset_home',

                repo_name=repo_name,

                revision=rev), title=tooltip(message(rev)),

                class_='tooltip') for rev in revs[:revs_limit] ]))

        compare_view = (' <div class="compare_view tooltip" title="%s">'

                        '<a href="%s">%s</a> '

                        '</div>' % (_('Show all combined changesets %s->%s' \

                                      % (revs[0], revs[-1])),

                                    url('changeset_home', repo_name=repo_name,

                                        revision='%s...%s' % (revs[0], revs[-1])

                                    ),

                                    _('compare view'))

                        )

        if len(revs) > revs_limit:

            uniq_id = revs[0]

            html_tmpl = ('<span> %s '

            '<a class="show_more" id="_%s" href="#more">%s</a> '

            '%s</span>')

            if not feed:

                cs_links.append(html_tmpl % (_('and'), uniq_id, _('%s more') \

                                        % (len(revs) - revs_limit),

                                        _('revisions')))

            if not feed:

                html_tmpl = '<span id="%s" style="display:none"> %s </span>'

            else:

                html_tmpl = '<span id="%s"> %s </span>'

            cs_links.append(html_tmpl % (uniq_id, ', '.join([link_to(rev,

                url('changeset_home',

                repo_name=repo_name, revision=rev),

                title=message(rev), class_='tooltip')

                for rev in revs[revs_limit:revs_top_limit]])))

        if len(revs) > 1:

            cs_links.append(compare_view)

        return ''.join(cs_links)

    def get_fork_name():

        repo_name = action_params

        return _('fork name ') + str(link_to(action_params, url('summary_home',

                                          repo_name=repo_name,)))

    action_map = {'user_deleted_repo':(_('[deleted] repository'), None),

           'user_created_repo':(_('[created] repository'), None),

           'user_forked_repo':(_('[forked] repository'), get_fork_name),

           'user_updated_repo':(_('[updated] repository'), None),

           'admin_deleted_repo':(_('[delete] repository'), None),

           'admin_created_repo':(_('[created] repository'), None),

           'admin_forked_repo':(_('[forked] repository'), None),

           'admin_updated_repo':(_('[updated] repository'), None),

           'push':(_('[pushed] into'), get_cs_links),

           'push_local':(_('[committed via RhodeCode] into'), get_cs_links),

           'push_remote':(_('[pulled from remote] into'), get_cs_links),

           'pull':(_('[pulled] from'), None),

           'started_following_repo':(_('[started following] repository'), None),

           'stopped_following_repo':(_('[stopped following] repository'), None),

            }

    action_str = action_map.get(action, action)

    if feed:

        action = action_str[0].replace('[', '').replace(']', '')

    else:

        action = action_str[0].replace('[', '<span class="journal_highlight">')\

                   .replace(']', '</span>')

    action_params_func = lambda :""

    if callable(action_str[1]):

        action_params_func = action_str[1]

    return [literal(action), action_params_func]

def action_parser_icon(user_log):

    action = user_log.action

    action_params = None

    x = action.split(':')

    if len(x) > 1:

        action, action_params = x

    tmpl = """<img src="%s%s" alt="%s"/>"""

    map = {'user_deleted_repo':'database_delete.png',

           'user_created_repo':'database_add.png',

           'user_forked_repo':'arrow_divide.png',

           'user_updated_repo':'database_edit.png',

           'admin_deleted_repo':'database_delete.png',

           'admin_created_repo':'database_add.png',

           'admin_forked_repo':'arrow_divide.png',

           'admin_updated_repo':'database_edit.png',

           'push':'script_add.png',

           'push_local':'script_edit.png',

           'push_remote':'connect.png',

           'pull':'down_16.png',

           'started_following_repo':'heart_add.png',

           'stopped_following_repo':'heart_delete.png',

            }

    return literal(tmpl % ((url('/images/icons/')),

                           map.get(action, action), action))

#==============================================================================

# PERMS

#==============================================================================

from rhodecode.lib.auth import HasPermissionAny, HasPermissionAll, \

HasRepoPermissionAny, HasRepoPermissionAll

#==============================================================================

# GRAVATAR URL

#==============================================================================

def gravatar_url(email_address, size=30):

    if (not str2bool(config['app_conf'].get('use_gravatar')) or

        not email_address or email_address == 'anonymous@rhodecode.org'):

        return url("/images/user%s.png" % size)

    ssl_enabled = 'https' == request.environ.get('wsgi.url_scheme')

    default = 'identicon'

    baseurl_nossl = "http://www.gravatar.com/avatar/"

    baseurl_ssl = "https://secure.gravatar.com/avatar/"

    baseurl = baseurl_ssl if ssl_enabled else baseurl_nossl

    if isinstance(email_address, unicode):

        #hashlib crashes on unicode items

        email_address = safe_str(email_address)

    # construct the url

    gravatar_url = baseurl + hashlib.md5(email_address.lower()).hexdigest() + "?"

    gravatar_url += urllib.urlencode({'d':default, 's':str(size)})

    return gravatar_url

#==============================================================================

# REPO PAGER, PAGER FOR REPOSITORY

#==============================================================================

class RepoPage(Page):

    def __init__(self, collection, page=1, items_per_page=20,

                 item_count=None, url=None, **kwargs):

        """Create a "RepoPage" instance. special pager for paging

        repository

        """

        self._url_generator = url

        # Safe the kwargs class-wide so they can be used in the pager() method

        self.kwargs = kwargs

        # Save a reference to the collection

        self.original_collection = collection

        self.collection = collection

        # The self.page is the number of the current page.

        # The first page has the number 1!

        try:

            self.page = int(page) # make it int() if we get it as a string

        except (ValueError, TypeError):

            self.page = 1

        self.items_per_page = items_per_page

        # Unless the user tells us how many items the collections has

        # we calculate that ourselves.

        if item_count is not None:

            self.item_count = item_count

        else:

            self.item_count = len(self.collection)

        # Compute the number of the first and last available page

        if self.item_count > 0:

            self.first_page = 1

            self.page_count = int(math.ceil(float(self.item_count) /

                                            self.items_per_page))

            self.last_page = self.first_page + self.page_count - 1

            # Make sure that the requested page number is the range of valid pages

            if self.page > self.last_page:

                self.page = self.last_page

            elif self.page < self.first_page:

                self.page = self.first_page

            # Note: the number of items on this page can be less than

            #       items_per_page if the last page is not full

            self.first_item = max(0, (self.item_count) - (self.page *

                                                          items_per_page))

            self.last_item = ((self.item_count - 1) - items_per_page *

                              (self.page - 1))

            self.items = list(self.collection[self.first_item:self.last_item + 1])

            # Links to previous and next page

            if self.page > self.first_page:

                self.previous_page = self.page - 1

            else:

                self.previous_page = None

            if self.page < self.last_page:

                self.next_page = self.page + 1

            else:

                self.next_page = None

        # No items available

        else:

            self.first_page = None

            self.page_count = 0

            self.last_page = None

            self.first_item = None

            self.last_item = None

            self.previous_page = None

            self.next_page = None

            self.items = []

        # This is a subclass of the 'list' type. Initialise the list now.

        list.__init__(self, reversed(self.items))

def changed_tooltip(nodes):

    """

    Generates a html string for changed nodes in changeset page.

    It limits the output to 30 entries

    :param nodes: LazyNodesGenerator

    """

    if nodes:

        pref = ': <br/> '

        suf = ''

        if len(nodes) > 30:

            suf = '<br/>' + _(' and %s more') % (len(nodes) - 30)

        return literal(pref + '<br/> '.join([safe_unicode(x.path)