Show cash + holdings value for investment account view (#1046)

* Handle missing tickers in security price syncs

* Show combined cash and holdings value on account page

* Improve partial locals

app/models/investment.rb

@@ -13,4 +13,35 @@ class Investment < ApplicationRecord
     [ "Roth 401k", "roth_401k" ],
     [ "Angel", "angel" ]
   ].freeze
+
+  def value
+    account.balance_money + holdings_value
+  end
+
+  def holdings_value
+    account.holdings.current.known_value.sum(&:amount) || Money.new(0, account.currency)
+  end
+
+  def series(period: Period.all, currency: account.currency)
+    balance_series = account.balances.in_period(period).where(currency: currency)
+    holding_series = account.holdings.known_value.in_period(period).where(currency: currency)
+
+    holdings_by_date = holding_series.group_by(&:date).transform_values do |holdings|
+      holdings.sum(&:amount)
+    end
+
+    combined_series = balance_series.map do |balance|
+      holding_amount = holdings_by_date[balance.date] || 0
+
+      { date: balance.date, value: Money.new(balance.balance + holding_amount, currency) }
+    end
+
+    if combined_series.empty? && period.date_range.end == Date.current
+      TimeSeries.new([ { date: Date.current, value: self.value.exchange_to(currency) } ])
+    else
+      TimeSeries.new(combined_series)
+    end
+  rescue Money::ConversionError
+    TimeSeries.new([])
+  end
 end