From 3c4cb4eeeb14e3fa0d585554283b057db7cc517a Mon Sep 17 00:00:00 2001
From: Simon Michael <simon@joyful.com>
Date: Wed, 7 Dec 2016 15:07:59 -0800
Subject: [PATCH] ui: --watch: track date only when a standard period is in
 effect

---
 hledger-lib/Hledger/Data/Period.hs         | 15 +++++++++++++--
 hledger-ui/Hledger/UI/AccountsScreen.hs    |  4 +++-
 hledger-ui/Hledger/UI/RegisterScreen.hs    |  4 +++-
 hledger-ui/Hledger/UI/TransactionScreen.hs |  4 +++-
 4 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/hledger-lib/Hledger/Data/Period.hs b/hledger-lib/Hledger/Data/Period.hs
index ea07bb0da..fe6e0dcf5 100644
--- a/hledger-lib/Hledger/Data/Period.hs
+++ b/hledger-lib/Hledger/Data/Period.hs
@@ -118,6 +118,17 @@ isLastDayOfMonth y m d =
     12 -> d==31
     _ -> False
 
+-- | Is this period a "standard" period, referencing a particular day, week, month, quarter, or year ?
+-- Periods of other durations, or infinite duration, or not starting on a standard period boundary, are not.
+isStandardPeriod = isStandardPeriod' . simplifyPeriod
+  where
+    isStandardPeriod' (DayPeriod _) = True
+    isStandardPeriod' (WeekPeriod _) = True
+    isStandardPeriod' (MonthPeriod _ _) = True
+    isStandardPeriod' (QuarterPeriod _ _) = True
+    isStandardPeriod' (YearPeriod _) = True
+    isStandardPeriod' _ = False
+
 -- | Render a period as a compact display string suitable for user output.
 --
 -- >>> showPeriod (WeekPeriod (fromGregorian 2016 7 25))
@@ -143,7 +154,7 @@ periodEnd p = me
   where
     DateSpan _ me = periodAsDateSpan p
 
--- | Move a standard period (day, week, month etc.) to the following period of same duration.
+-- | Move a standard period to the following period of same duration.
 -- Non-standard periods are unaffected.
 periodNext :: Period -> Period
 periodNext (DayPeriod b) = DayPeriod (addDays 1 b)
@@ -155,7 +166,7 @@ periodNext (QuarterPeriod y q) = QuarterPeriod y (q+1)
 periodNext (YearPeriod y) = YearPeriod (y+1)
 periodNext p = p
 
--- | Move a standard period (day, week, month etc.) to the preceding period of same duration.
+-- | Move a standard period to the preceding period of same duration.
 -- Non-standard periods are unaffected.
 periodPrevious :: Period -> Period
 periodPrevious (DayPeriod b) = DayPeriod (addDays (-1) b)
diff --git a/hledger-ui/Hledger/UI/AccountsScreen.hs b/hledger-ui/Hledger/UI/AccountsScreen.hs
index 7a51e0783..e0f670988 100644
--- a/hledger-ui/Hledger/UI/AccountsScreen.hs
+++ b/hledger-ui/Hledger/UI/AccountsScreen.hs
@@ -291,8 +291,10 @@ asHandle ui0@UIState{
         VtyEvent (EvKey (KChar c)   []) | c `elem` ['?'] -> continue $ setMode Help ui
         -- XXX AppEvents currently handled only in Normal mode
         -- XXX be sure we don't leave unconsumed events piling up
-        AppEvent (DateChange old _) | periodContainsDate (reportPeriod ui) old ->
+        AppEvent (DateChange old _) | isStandardPeriod p && p `periodContainsDate` old ->
           continue $ regenerateScreens j d $ setReportPeriod (DayPeriod d) ui
+          where
+            p = reportPeriod ui
         e | e `elem` [VtyEvent (EvKey (KChar 'g') []), AppEvent FileChange] ->
           liftIO (uiReloadJournal copts d ui) >>= continue
         VtyEvent (EvKey (KChar 'I') []) -> continue $ uiCheckBalanceAssertions d (toggleIgnoreBalanceAssertions ui)
diff --git a/hledger-ui/Hledger/UI/RegisterScreen.hs b/hledger-ui/Hledger/UI/RegisterScreen.hs
index 542d8ae85..a09ff7855 100644
--- a/hledger-ui/Hledger/UI/RegisterScreen.hs
+++ b/hledger-ui/Hledger/UI/RegisterScreen.hs
@@ -267,8 +267,10 @@ rsHandle ui@UIState{
         VtyEvent (EvKey (KChar 'q') []) -> halt ui
         VtyEvent (EvKey KEsc        []) -> continue $ resetScreens d ui
         VtyEvent (EvKey (KChar c)   []) | c `elem` ['?'] -> continue $ setMode Help ui
-        AppEvent (DateChange old _) | periodContainsDate (reportPeriod ui) old ->
+        AppEvent (DateChange old _) | isStandardPeriod p && p `periodContainsDate` old ->
           continue $ regenerateScreens j d $ setReportPeriod (DayPeriod d) ui
+          where
+            p = reportPeriod ui
         e | e `elem` [VtyEvent (EvKey (KChar 'g') []), AppEvent FileChange] ->
           liftIO (uiReloadJournal copts d ui) >>= continue
         VtyEvent (EvKey (KChar 'I') []) -> continue $ uiCheckBalanceAssertions d (toggleIgnoreBalanceAssertions ui)
diff --git a/hledger-ui/Hledger/UI/TransactionScreen.hs b/hledger-ui/Hledger/UI/TransactionScreen.hs
index 301fa6d99..043ac5e49 100644
--- a/hledger-ui/Hledger/UI/TransactionScreen.hs
+++ b/hledger-ui/Hledger/UI/TransactionScreen.hs
@@ -129,8 +129,10 @@ tsHandle ui@UIState{aScreen=s@TransactionScreen{tsTransaction=(i,t)
         VtyEvent (EvKey (KChar 'E') []) -> suspendAndResume $ void (runEditor pos f) >> uiReloadJournalIfChanged copts d j ui
           where
             (pos,f) = let GenericSourcePos f l c = tsourcepos t in (Just (l, Just c),f)
-        AppEvent (DateChange old _) | periodContainsDate (reportPeriod ui) old ->
+        AppEvent (DateChange old _) | isStandardPeriod p && p `periodContainsDate` old ->
           continue $ regenerateScreens j d $ setReportPeriod (DayPeriod d) ui
+          where
+            p = reportPeriod ui
         e | e `elem` [VtyEvent (EvKey (KChar 'g') []), AppEvent FileChange] -> do
           d <- liftIO getCurrentDay
           ej <- liftIO $ journalReload copts