1 files changed, 42 insertions, 0 deletions
diff --git a/app/models/target.rb b/app/models/target.rb
new file mode 100644
index 0000000..3063b42
--- /dev/null
+++ b/app/models/target.rb
@@ -0,0 +1,42 @@
+# app/models/target.rb
+class Target < ApplicationRecord
+  has_many :target_allocations, dependent: :destroy
+  has_many :nutrient_profiles, through: :target_allocations
+
+  accepts_nested_attributes_for :target_allocations, allow_destroy: true
+  validate :percentages_sum_to_100
+
+  def weighted_requirements
+    totals = Hash.new(0.0)
+    denom  = 100.0
+
+    target_allocations.includes(:nutrient_profile).each do |alloc|
+      profile = alloc.nutrient_profile
+      next unless profile
+
+      weight = (alloc.percentage || 0).to_f / denom
+      next if weight <= 0
+
+      # Prefer the helper, but gracefully fall back to slicing attributes.
+      reqs = if profile.respond_to?(:requirements_hash)
+               profile.requirements_hash
+      else
+               profile.attributes.slice(*NutrientProfile::NUTRIENT_KEYS.map(&:to_s))
+      end
+
+      reqs.each do |nutrient_key, value|
+        next if value.nil?
+        totals[nutrient_key.to_s] += value.to_f * weight
+      end
+    end
+
+    totals
+  end
+
+  private
+
+  def percentages_sum_to_100
+    sum = target_allocations.reject(&:marked_for_destruction?).sum { |a| a.percentage.to_f }
+    errors.add(:base, "La somme des pourcentages doit être égale à 100%") unless (sum - 100.0).abs <= 0.01
+  end
+end