Account namespace updates: part 5 (valuations) (#901)

* Move Valuation to Account namespace

* Move account history to controller

* Clean up valuation controller and views

* Translations and cleanup

* Remove unused scopes and methods

* Pass brakeman

app/models/account/valuation.rb

@@ -0,0 +1,52 @@
+class Account::Valuation < ApplicationRecord
+  include Monetizable
+
+  monetize :value
+
+  belongs_to :account
+
+  validates :account, :date, :value, presence: true
+  validates :date, uniqueness: { scope: :account_id }
+
+  scope :chronological, -> { order(:date) }
+  scope :reverse_chronological, -> { order(date: :desc) }
+
+  def trend
+    @trend ||= create_trend
+  end
+
+  def first_of_series?
+    account.valuations.chronological.limit(1).pluck(:date).first == self.date
+  end
+
+  def last_of_series?
+    account.valuations.reverse_chronological.limit(1).pluck(:date).first == self.date
+  end
+
+  def sync_account_later
+    if destroyed?
+      sync_start_date = previous_valuation&.date
+    else
+      sync_start_date = [ date_previously_was, date ].compact.min
+    end
+
+    account.sync_later(sync_start_date)
+  end
+
+  private
+
+    def previous_valuation
+      @previous_valuation ||= self.account
+                                .valuations
+                                .where("date < ?", date)
+                                .order(date: :desc)
+                                  .first
+    end
+
+    def create_trend
+      TimeSeries::Trend.new \
+        current: self.value,
+        previous: previous_valuation&.value,
+        favorable_direction: account.favorable_direction
+    end
+end