Add a locale-aware relative-time helper; drop stale locale overrides

Node.recently_changed and the new dashboard need "X ago" rendered
correctly in both locales. Rails' own distance_of_time_in_words/
time_ago_in_words can't do this on their own -- the scope option
changes which translation key is looked up, not the underlying
grammar, and German's "vor" requires dative case, which is a
different word form than the nominative plural Rails computes by
default. relative_time_phrase/relative_distance is a small, from-
scratch bucketing helper instead, with an explicit, hand-checked
translation table per unit per locale.

Also removes de.yml's datetime.distance_in_words and activerecord.
errors blocks. Both used the old {{count}}/{{model}} interpolation
syntax the current i18n gem no longer recognizes -- it silently
leaves the literal placeholder text in the rendered output rather
than erroring, which is why this went unnoticed until now. Both were
shadowing rails-i18n's own current, correct translations for exactly
these keys; deleting the local override lets the gem's version take
over instead of maintaining a second, broken copy.

4 files changed, 80 insertions, 66 deletions

diff --git a/app/helpers/datetime_helper.rb b/app/helpers/datetime_helper.rb
new file mode 100644
index 0000000..8497b1c
--- /dev/null
+++ b/app/helpers/datetime_helper.rb
@@ -0,0 +1,53 @@
+module DatetimeHelper
+
+  def relative_distance(time, now = Time.current)
+    seconds = (now - time).abs
+
+    case seconds
+    when 0...90
+      [1, :minute]
+    when 90...45.minutes
+      [(seconds / 60).round, :minute]
+    when 45.minutes...24.hours
+      [(seconds / 1.hour).round, :hour]
+    when 24.hours...30.days
+      [(seconds / 1.day).round, :day]
+    when 30.days...365.days
+      [(seconds / 30.days).round, :month]
+    else
+      [(seconds / 365.days).round, :year]
+    end
+  end
+
+  RELATIVE_TIME_UNIT_FORMS = {
+    en: {
+      minute: { one: "minute", other: "minutes" },
+      hour:   { one: "hour",   other: "hours" },
+      day:    { one: "day",    other: "days" },
+      month:  { one: "month",  other: "months" },
+      year:   { one: "year",   other: "years" },
+    },
+    de: {
+      # "other" here is the DATIVE plural needed after "vor" -- not the
+      # nominative plural you'd use standing alone ("3 Tage" vs "vor 3
+      # Tagen"). All five happen to be the nominative plural + "n", since
+      # none of them already end in -n or -s -- a property of these five
+      # specific words, not a rule to extend to new units without checking.
+      minute: { one: "Minute", other: "Minuten" },
+      hour:   { one: "Stunde", other: "Stunden" },
+      day:    { one: "Tag",    other: "Tagen" },
+      month:  { one: "Monat",  other: "Monaten" },
+      year:   { one: "Jahr",   other: "Jahren" },
+    },
+  }.freeze
+
+  def relative_time_phrase(time, now = Time.current)
+    count, unit = relative_distance(time, now)
+    locale = I18n.locale.to_sym
+    forms = RELATIVE_TIME_UNIT_FORMS.fetch(locale, RELATIVE_TIME_UNIT_FORMS[:en])
+    word = forms.fetch(unit).fetch(count == 1 ? :one : :other)
+
+    locale == :de ? "vor #{count} #{word}" : "#{count} #{word} ago"
+  end
+
+end
diff --git a/config/locales/de.yml b/config/locales/de.yml
index 1f2222c..550ccb3 100644
--- a/config/locales/de.yml
+++ b/config/locales/de.yml
@@ -14,6 +14,10 @@ de:
   open_days_label: "Offene Tage"
   upcoming_events: "Weitere Termine"
   open_today: "Das Chaos, lokal und heute offen"
+  published: "veröffentlicht"
+  published_by: "veröffentlicht durch %{editor}"
+  editor_self: "du"
+  publisher_self: "dich"
   date:
     formats:
       default: "%d.%m.%Y"
@@ -29,7 +33,6 @@ de:
       - :day
       - :month
       - :year
-
   time:
     formats:
       default: "%A, %e. %B %Y, %H:%M Uhr"
@@ -41,42 +44,6 @@ de:
     am: "vormittags"
     pm: "nachmittags"
 
-  datetime:
-    distance_in_words:
-      half_a_minute: 'eine halbe Minute'
-      less_than_x_seconds:
-        zero: 'weniger als 1 Sekunde'
-        one: 'weniger als 1 Sekunde'
-        other: 'weniger als {{count}} Sekunden'
-      x_seconds:
-        one: '1 Sekunde'
-        other: '{{count}} Sekunden'
-      less_than_x_minutes:
-        zero: 'weniger als 1 Minute'
-        one: 'weniger als eine Minute'
-        other: 'weniger als {{count}} Minuten'
-      x_minutes:
-        one: '1 Minute'
-        other: '{{count}} Minuten'
-      about_x_hours:
-        one: 'etwa 1 Stunde'
-        other: 'etwa {{count}} Stunden'
-      x_days:
-        one: '1 Tag'
-        other: '{{count}} Tage'
-      about_x_months:
-        one: 'etwa 1 Monat'
-        other: 'etwa {{count}} Monate'
-      x_months:
-        one: '1 Monat'
-        other: '{{count}} Monate'
-      about_x_years:
-        one: 'etwa 1 Jahr'
-        other: 'etwa {{count}} Jahre'
-      over_x_years:
-        one: 'mehr als 1 Jahr'
-        other: 'mehr als {{count}} Jahre'
-
   number:
     format:
       precision: 2
@@ -105,35 +72,6 @@ de:
       sentence_connector: "und"
       skip_last_comma: true
 
-  activerecord:
-    errors:
-      template:
-        header:
-          one: 1 error prohibited this {{model}} from being saved
-          other: "{{count}} errors prohibited this {{model}} from being saved"
-        body: "There were problems with the following fields:"
-
-      messages:
-        inclusion: "is not included in the list"
-        exclusion: "is reserved"
-        invalid: "is invalid"
-        confirmation: "doesn't match confirmation"
-        accepted: "must be accepted"
-        empty: "can't be empty"
-        blank: "can't be blank"
-        too_long: "is too long (maximum is {{count}} characters)"
-        too_short: "is too short (minimum is {{count}} characters)"
-        wrong_length: "is the wrong length (should be {{count}} characters)"
-        taken: "has already been taken"
-        not_a_number: "is not a number"
-        greater_than: "must be greater than {{count}}"
-        greater_than_or_equal_to: "must be greater than or equal to {{count}}"
-        equal_to: "must be equal to {{count}}"
-        less_than: "must be less than {{count}}"
-        less_than_or_equal_to: "must be less than or equal to {{count}}"
-        odd: "must be odd"
-        even: "must be even"
-
   will_paginate:
     previous_label: "← Zurück"
     previous_aria_label: "Vorherige Seite"
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 59c7304..73271ed 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -15,6 +15,10 @@ en:
   open_days_label: "Open days"
   upcoming_events: "Upcoming events"
   open_today: "Open today"
+  published: "published"
+  published_by: "published by %{editor}"
+  publisher_self: "you"
+  editor_self: "you"
 
   time:
     formats:
diff --git a/test/models/helpers/datetime_helper_test.rb b/test/models/helpers/datetime_helper_test.rb
new file mode 100644
index 0000000..a24e5d3
--- /dev/null
+++ b/test/models/helpers/datetime_helper_test.rb
@@ -0,0 +1,19 @@
+require 'test_helper'
+
+class DatetimeHelperTest < ActionView::TestCase
+  test "relative_time_phrase pluralizes correctly in English and German" do
+    travel_to Time.zone.parse("2026-07-12 12:00:00") do
+      I18n.with_locale(:en) do
+        assert_equal "1 day ago", relative_time_phrase(1.day.ago)
+        assert_equal "3 days ago", relative_time_phrase(3.days.ago)
+      end
+      I18n.with_locale(:de) do
+        assert_equal "vor 1 Tag", relative_time_phrase(1.day.ago)
+        assert_equal "vor 3 Tagen", relative_time_phrase(3.days.ago)
+        assert_equal "vor 1 Monat", relative_time_phrase(30.days.ago)
+        assert_equal "vor 2 Monaten", relative_time_phrase(45.days.ago)
+        assert_equal "vor 2 Jahren", relative_time_phrase(2.years.ago)
+      end
+    end
+  end
+end