# -*- coding: utf-8 -*-
from zope.i18n import translate
from Acquisition import aq_inner
from Products.Five.browser import BrowserView
from Products.Five.browser.pagetemplatefile import ViewPageTemplateFile
from Products.CMFCore.utils import getToolByName
from Products.CMFEditions import CMFEditionsMessageFactory as _


class DiffView(BrowserView):
    template = ViewPageTemplateFile("diff.pt")

    def __init__(self, *args):
        super(DiffView, self).__init__(*args)
        self.repo_tool = getToolByName(self.context, "portal_repository")

    def getVersion(self, version):
        context = aq_inner(self.context)
        if version == "current":
            return context
        else:
            return self.repo_tool.retrieve(context, int(version)).object

    def versionName(self, version):
        """
        Translate the version name. This is needed to allow translation when `version`
        is the string 'current'.
        """
        return _(version)

    def versionTitle(self, version):
        version_name = self.versionName(version)

        return translate(
            _(u"version ${version}",
              mapping=dict(version=version_name)),
            context=self.request
        )

    def __call__(self):
        version1 = self.request.get("one", "current")
        version2 = self.request.get("two", "current")

        history_metadata = self.repo_tool.getHistoryMetadata(self.context)
        retrieve = history_metadata.retrieve
        getId = history_metadata.getVersionId
        history = self.history = []
        # Count backwards from most recent to least recent
        for i in xrange(history_metadata.getLength(countPurged=False)-1, -1, -1):
            version = retrieve(i, countPurged=False)['metadata'].copy()
            version['version_id'] = getId(i, countPurged=False)
            history.append(version)
        dt = getToolByName(self.context, "portal_diff")
        self.changeset = dt.createChangeSet(
            self.getVersion(version2),
            self.getVersion(version1),
            id1=self.versionTitle(version2),
            id2=self.versionTitle(version1))
        self.changes = [change for change in self.changeset.getDiffs()
                        if not change.same]

        return self.template()


class CanDiff(BrowserView):

    def can_diff(self):
        """Return True if content is diffable
        """
        context = self.context
        portal_diff = getToolByName(context, 'portal_diff', None)
        return portal_diff \
            and len(portal_diff.getDiffForPortalType(context.portal_type)) > 0