def update_suggestions(self, text=""):
        """
            * from previous activity | set time | minutes ago | start now
            * to ongoing | set time

            * activity
            * [@category]
            * #tags, #tags, #tags

            * we will leave description for later

            all our magic is space separated, strictly, start-end can be just dash

            phases:

            [start_time] | [-end_time] | activity | [@category] | [#tag]
        """

        res = []

        fact = Fact(text)
        now = dt.datetime.now()

        # figure out what we are looking for
        # time -> activity[@category] -> tags -> description
        # presence of an attribute means that we are not looking for the previous one
        # we still might be looking for the current one though
        looking_for = "start_time"
        fields = ["start_time", "end_time", "activity", "category", "tags", "description", "done"]
        for field in reversed(fields):
            if getattr(fact, field, None):
                looking_for = field
                if text[-1] == " ":
                    looking_for = fields[fields.index(field)+1]
                break


        fragments = [f for f in re.split("[\s|#]", text)]
        current_fragment = fragments[-1] if fragments else ""


        search = extract_search(text)

        matches = []
        for match, score in self.suggestions:
            if search in match:
                if match.startswith(search):
                    score += 10**8 # boost beginnings
                matches.append((match, score))

        # need to limit these guys, sorry
        matches = sorted(matches, key=lambda x: x[1], reverse=True)[:7]

        for match, score in matches:
            label = (fact.start_time or now).strftime("%H:%M")
            if fact.end_time:
                label += fact.end_time.strftime("-%H:%M")

            markup_label = label + " " + (stuff.escape_pango(match).replace(search, "<b>%s</b>" % search) if search else match)
            label += " " + match

            res.append(DataRow(markup_label, match, label))

        # list of tuples (description, variant)
        variants = []

        if self.original_fact:
            # editing an existing fact

            variant_fact = None
            if self.original_fact.end_time is None:
                description = "stop now"
                variant_fact = self.original_fact.copy()
                variant_fact.end_time = now
            elif self.original_fact == self.todays_facts[-1]:
                # that one is too dangerous, except for the last entry
                description = "keep up"
                # Do not use Fact(..., end_time=None): it would be a no-op
                variant_fact = self.original_fact.copy()
                variant_fact.end_time = None

            if variant_fact:
                variant = variant_fact.serialized(prepend_date=False)
                variants.append((description, variant))

        else:
            # brand new fact
            description = "start now"
            variant = now.strftime("%H:%M ")
            variants.append((description, variant))

            prev_fact = self.todays_facts[-1] if self.todays_facts else None
            if prev_fact and prev_fact.end_time:
                since = stuff.format_duration(now - prev_fact.end_time)
                description = "from previous activity, %s ago" % since
                variant = prev_fact.end_time.strftime("%H:%M ")
                variants.append((description, variant))

            description = "start activity -n minutes ago (1 or 3 digits allowed)"
            variant = "-"
            variants.append((description, variant))

        text = text.strip()
        if text:
            description = "clear"
            variant = ""
            variants.append((description, variant))

        for (description, variant) in variants:
            res.append(DataRow(variant, description=description))

        self.complete_tree.set_rows(res)
* from previous activity | set time | minutes ago | start now
            * to ongoing | set time

            * activity
            * [@category]
            * #tags, #tags, #tags

            * we will leave description for later

            all our magic is space separated, strictly, start-end can be just dash

            phases:

            [start_time] | [-end_time] | activity | [@category] | [#tag]