1 files changed, 21 insertions, 0 deletions
diff --git a/app/helpers/nutrients_helper.rb b/app/helpers/nutrients_helper.rb
new file mode 100644
index 0000000..de98dc3
--- /dev/null
+++ b/app/helpers/nutrients_helper.rb
@@ -0,0 +1,21 @@
+module NutrientsHelper
+  NUTRIENTS = %i[nno3 p k ca mg s na cl si fe zn b mn cu mo nnh4].freeze
+
+  def percent_delta(measured, target)
+    return 0.0 if target.to_f.zero?
+    ((measured.to_f - target.to_f) / target.to_f) * 100.0
+  end
+
+  def fmt(v)
+    number_with_precision(v, precision: 2, strip_insignificant_zeros: true)
+  end
+
+  def delta_badge_class(delta)
+    d = delta.abs
+    case d
+    when d < 0 then "bg-info"
+    when 0..5 then "bg-secondary"
+    else "bg-warning"
+    end
+  end
+end