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reports/monthly_net_worth.lua

@@ -0,0 +1,60 @@
+function account_series_map(accounts, tabulation)
+    map = {}
+
+    for i=1,100 do -- we're not messing with accounts more than 100 levels deep
+        all_handled = true
+        for id, acct in pairs(accounts) do
+            if not map[id] then
+                all_handled = false
+                if not acct.parent then
+                    map[id] = tabulation:series(acct.name)
+                elseif map[acct.parent.accountid] then
+                    map[id] = map[acct.parent.accountid]:series(acct.name)
+                end
+            end
+        end
+        if all_handled then
+            return map
+        end
+    end
+
+    error("Accounts nested (at least) 100 levels deep")
+end
+
+function generate()
+    year = date.now().year
+
+    accounts = get_accounts()
+    t = tabulation.new(12)
+    t:title(year .. " Monthly Net Worth")
+    series_map = account_series_map(accounts, t)
+    default_currency = get_default_currency()
+
+    for month=1,12 do
+        end_date = date.new(year, month+1, 1)
+
+        t:label(month, tostring(end_date))
+
+        for id, acct in pairs(accounts) do
+            series = series_map[id]
+            if acct.type ~= account.Expense and acct.type ~= account.Income and acct.type ~= account.Trading then
+                balance = acct:balance(end_date)
+                multiplier = 1
+                if acct.security ~= default_currency and balance.amount ~= 0 then
+                    price = acct.security:closestprice(default_currency, end_date)
+                    if price == nil then
+                        --[[
+                        -- This should contain code to warn the user that their report is missing some information
+                        --]]
+                        multiplier = 0
+                    else
+                        multiplier = price.value
+                    end
+                end
+                series:value(month, balance.amount * multiplier)
+            end
+        end
+    end
+
+    return t
+end