Budgeting V1 (#1609)

* Budgeting V1

* Basic UI template

* Fully scaffolded budgeting v1

* Basic working budget

* Finalize donut chart for budgets

* Allow categorization of loan payments for budget

* Include loan payments in incomes_and_expenses scope

* Add budget allocations progress

* Empty states

* Clean up budget methods

* Category aggregation queries

* Handle overage scenarios in form

* Finalize budget donut chart controller

* Passing tests

* Fix allocation naming

* Add income category migration

* Native support for uncategorized budget category

* Formatting

* Fix subcategory sort order, padding

* Fix calculation for category rollups in budget

app/models/family.rb

@@ -17,6 +17,8 @@ class Family < ApplicationRecord
   has_many :issues, through: :accounts
   has_many :holdings, through: :accounts
   has_many :plaid_items, dependent: :destroy
+  has_many :budgets, dependent: :destroy
+  has_many :budget_categories, through: :budgets
 
   validates :locale, inclusion: { in: I18n.available_locales.map(&:to_s) }
   validates :date_format, inclusion: { in: DATE_FORMATS }
@@ -56,6 +58,22 @@ class Family < ApplicationRecord
     ).link_token
   end
 
+  def income_categories_with_totals(date: Date.current)
+    categories_with_stats(classification: "income", date: date)
+  end
+
+  def expense_categories_with_totals(date: Date.current)
+    categories_with_stats(classification: "expense", date: date)
+  end
+
+  def category_stats
+    CategoryStats.new(self)
+  end
+
+  def budgeting_stats
+    BudgetingStats.new(self)
+  end
+
   def snapshot(period = Period.all)
     query = accounts.active.joins(:balances)
               .where("account_balances.currency = ?", self.currency)
@@ -172,4 +190,41 @@ class Family < ApplicationRecord
   def primary_user
     users.order(:created_at).first
   end
+
+  def oldest_entry_date
+    entries.order(:date).first&.date || Date.current
+  end
+
+  private
+    CategoriesWithTotals = Struct.new(:total_money, :category_totals, keyword_init: true)
+    CategoryWithStats = Struct.new(:category, :amount_money, :percentage, keyword_init: true)
+
+    def categories_with_stats(classification:, date: Date.current)
+      totals = category_stats.month_category_totals(date: date)
+
+      classified_totals = totals.category_totals.select { |t| t.classification == classification }
+
+      if classification == "income"
+        total = totals.total_income
+        categories_scope = categories.incomes
+      else
+        total = totals.total_expense
+        categories_scope = categories.expenses
+      end
+
+      categories_with_uncategorized = categories_scope + [ categories_scope.uncategorized ]
+
+      CategoriesWithTotals.new(
+        total_money: Money.new(total, currency),
+        category_totals: categories_with_uncategorized.map do |category|
+          ct = classified_totals.find { |ct| ct.category_id == category&.id }
+
+          CategoryWithStats.new(
+            category: category,
+            amount_money: Money.new(ct&.amount || 0, currency),
+            percentage: ct&.percentage || 0
+          )
+        end
+      )
+    end
 end