hledger/hledger-lib/Hledger/Data/Dates.hs
Simon Michael ce7e155934 parsing: fix obscured date parse errors with parsec 3; require split
With parsec 3, invalid date errors were not being reported properly.
This should be more robust.
2010-09-03 23:22:58 +00:00

493 lines
18 KiB
Haskell

{-|
Date parsing and utilities for hledger.
For date and time values, we use the standard Day and UTCTime types.
A 'SmartDate' is a date which may be partially-specified or relative.
Eg 2008\/12\/31, but also 2008\/12, 12\/31, tomorrow, last week, next year.
We represent these as a triple of strings like (\"2008\",\"12\",\"\"),
(\"\",\"\",\"tomorrow\"), (\"\",\"last\",\"week\").
A 'DateSpan' is the span of time between two specific calendar dates, or
an open-ended span where one or both dates are unspecified. (A date span
with both ends unspecified matches all dates.)
An 'Interval' is ledger's "reporting interval" - weekly, monthly,
quarterly, etc.
-}
module Hledger.Data.Dates
where
import Data.Time.Format
import Data.Time.Calendar.OrdinalDate
import Safe (readMay)
import System.Locale (defaultTimeLocale)
import Text.ParserCombinators.Parsec
import Hledger.Data.Types
import Hledger.Data.Utils
showDate :: Day -> String
showDate = formatTime defaultTimeLocale "%C%y/%m/%d"
getCurrentDay :: IO Day
getCurrentDay = do
t <- getZonedTime
return $ localDay (zonedTimeToLocalTime t)
elapsedSeconds :: Fractional a => UTCTime -> UTCTime -> a
elapsedSeconds t1 = realToFrac . diffUTCTime t1
-- | Split a DateSpan into one or more consecutive spans at the specified interval.
splitSpan :: Interval -> DateSpan -> [DateSpan]
splitSpan _ (DateSpan Nothing Nothing) = [DateSpan Nothing Nothing]
splitSpan NoInterval s = [s]
splitSpan Daily s = splitspan startofday nextday s
splitSpan Weekly s = splitspan startofweek nextweek s
splitSpan Monthly s = splitspan startofmonth nextmonth s
splitSpan Quarterly s = splitspan startofquarter nextquarter s
splitSpan Yearly s = splitspan startofyear nextyear s
splitspan :: (Day -> Day) -> (Day -> Day) -> DateSpan -> [DateSpan]
splitspan _ _ (DateSpan Nothing Nothing) = []
splitspan start next (DateSpan Nothing (Just e)) = [DateSpan (Just $ start e) (Just $ next $ start e)]
splitspan start next (DateSpan (Just b) Nothing) = [DateSpan (Just $ start b) (Just $ next $ start b)]
splitspan start next span@(DateSpan (Just b) (Just e))
| b == e = [span]
| otherwise = splitspan' start next span
where
splitspan' start next (DateSpan (Just b) (Just e))
| b >= e = []
| otherwise = DateSpan (Just s) (Just n)
: splitspan' start next (DateSpan (Just n) (Just e))
where s = start b
n = next s
splitspan' _ _ _ = error "won't happen, avoids warnings"
-- | Count the days in a DateSpan, or if it is open-ended return Nothing.
daysInSpan :: DateSpan -> Maybe Integer
daysInSpan (DateSpan (Just d1) (Just d2)) = Just $ diffDays d2 d1
daysInSpan _ = Nothing
-- | Does the span include the given date ?
spanContainsDate :: DateSpan -> Day -> Bool
spanContainsDate (DateSpan Nothing Nothing) _ = True
spanContainsDate (DateSpan Nothing (Just e)) d = d < e
spanContainsDate (DateSpan (Just b) Nothing) d = d >= b
spanContainsDate (DateSpan (Just b) (Just e)) d = d >= b && d < e
-- | Combine two datespans, filling any unspecified dates in the first
-- with dates from the second.
orDatesFrom (DateSpan a1 b1) (DateSpan a2 b2) = DateSpan a b
where a = if isJust a1 then a1 else a2
b = if isJust b1 then b1 else b2
-- | Parse a period expression to an Interval and overall DateSpan using
-- the provided reference date, or return a parse error.
parsePeriodExpr :: Day -> String -> Either ParseError (Interval, DateSpan)
parsePeriodExpr refdate = parsewith (periodexpr refdate)
-- | Show a DateSpan as a human-readable pseudo-period-expression string.
dateSpanAsText :: DateSpan -> String
dateSpanAsText (DateSpan Nothing Nothing) = "all"
dateSpanAsText (DateSpan Nothing (Just e)) = printf "to %s" (show e)
dateSpanAsText (DateSpan (Just b) Nothing) = printf "from %s" (show b)
dateSpanAsText (DateSpan (Just b) (Just e)) = printf "%s to %s" (show b) (show e)
-- | Convert a single smart date string to a date span using the provided
-- reference date, or raise an error.
spanFromSmartDateString :: Day -> String -> DateSpan
spanFromSmartDateString refdate s = spanFromSmartDate refdate sdate
where
sdate = fromparse $ parsewith smartdateonly s
spanFromSmartDate :: Day -> SmartDate -> DateSpan
spanFromSmartDate refdate sdate = DateSpan (Just b) (Just e)
where
(ry,rm,_) = toGregorian refdate
(b,e) = span sdate
span :: SmartDate -> (Day,Day)
span ("","","today") = (refdate, nextday refdate)
span ("","this","day") = (refdate, nextday refdate)
span ("","","yesterday") = (prevday refdate, refdate)
span ("","last","day") = (prevday refdate, refdate)
span ("","","tomorrow") = (nextday refdate, addDays 2 refdate)
span ("","next","day") = (nextday refdate, addDays 2 refdate)
span ("","last","week") = (prevweek refdate, thisweek refdate)
span ("","this","week") = (thisweek refdate, nextweek refdate)
span ("","next","week") = (nextweek refdate, startofweek $ addDays 14 refdate)
span ("","last","month") = (prevmonth refdate, thismonth refdate)
span ("","this","month") = (thismonth refdate, nextmonth refdate)
span ("","next","month") = (nextmonth refdate, startofmonth $ addGregorianMonthsClip 2 refdate)
span ("","last","quarter") = (prevquarter refdate, thisquarter refdate)
span ("","this","quarter") = (thisquarter refdate, nextquarter refdate)
span ("","next","quarter") = (nextquarter refdate, startofquarter $ addGregorianMonthsClip 6 refdate)
span ("","last","year") = (prevyear refdate, thisyear refdate)
span ("","this","year") = (thisyear refdate, nextyear refdate)
span ("","next","year") = (nextyear refdate, startofyear $ addGregorianYearsClip 2 refdate)
span ("","",d) = (day, nextday day) where day = fromGregorian ry rm (read d)
span ("",m,"") = (startofmonth day, nextmonth day) where day = fromGregorian ry (read m) 1
span ("",m,d) = (day, nextday day) where day = fromGregorian ry (read m) (read d)
span (y,"","") = (startofyear day, nextyear day) where day = fromGregorian (read y) 1 1
span (y,m,"") = (startofmonth day, nextmonth day) where day = fromGregorian (read y) (read m) 1
span (y,m,d) = (day, nextday day) where day = fromGregorian (read y) (read m) (read d)
showDay :: Day -> String
showDay day = printf "%04d/%02d/%02d" y m d where (y,m,d) = toGregorian day
-- | Convert a smart date string to an explicit yyyy\/mm\/dd string using
-- the provided reference date, or raise an error.
fixSmartDateStr :: Day -> String -> String
fixSmartDateStr t s = either parseerror id $ fixSmartDateStrEither t s
-- | A safe version of fixSmartDateStr.
fixSmartDateStrEither :: Day -> String -> Either ParseError String
fixSmartDateStrEither t s = case parsewith smartdateonly (lowercase s) of
Right sd -> Right $ showDay $ fixSmartDate t sd
Left e -> Left e
-- | Convert a SmartDate to an absolute date using the provided reference date.
fixSmartDate :: Day -> SmartDate -> Day
fixSmartDate refdate sdate = fix sdate
where
fix :: SmartDate -> Day
fix ("","","today") = fromGregorian ry rm rd
fix ("","this","day") = fromGregorian ry rm rd
fix ("","","yesterday") = prevday refdate
fix ("","last","day") = prevday refdate
fix ("","","tomorrow") = nextday refdate
fix ("","next","day") = nextday refdate
fix ("","last","week") = prevweek refdate
fix ("","this","week") = thisweek refdate
fix ("","next","week") = nextweek refdate
fix ("","last","month") = prevmonth refdate
fix ("","this","month") = thismonth refdate
fix ("","next","month") = nextmonth refdate
fix ("","last","quarter") = prevquarter refdate
fix ("","this","quarter") = thisquarter refdate
fix ("","next","quarter") = nextquarter refdate
fix ("","last","year") = prevyear refdate
fix ("","this","year") = thisyear refdate
fix ("","next","year") = nextyear refdate
fix ("","",d) = fromGregorian ry rm (read d)
fix ("",m,"") = fromGregorian ry (read m) 1
fix ("",m,d) = fromGregorian ry (read m) (read d)
fix (y,"","") = fromGregorian (read y) 1 1
fix (y,m,"") = fromGregorian (read y) (read m) 1
fix (y,m,d) = fromGregorian (read y) (read m) (read d)
(ry,rm,rd) = toGregorian refdate
prevday :: Day -> Day
prevday = addDays (-1)
nextday = addDays 1
startofday = id
thisweek = startofweek
prevweek = startofweek . addDays (-7)
nextweek = startofweek . addDays 7
startofweek day = fromMondayStartWeek y w 1
where
(y,_,_) = toGregorian day
(w,_) = mondayStartWeek day
thismonth = startofmonth
prevmonth = startofmonth . addGregorianMonthsClip (-1)
nextmonth = startofmonth . addGregorianMonthsClip 1
startofmonth day = fromGregorian y m 1 where (y,m,_) = toGregorian day
thisquarter = startofquarter
prevquarter = startofquarter . addGregorianMonthsClip (-3)
nextquarter = startofquarter . addGregorianMonthsClip 3
startofquarter day = fromGregorian y (firstmonthofquarter m) 1
where
(y,m,_) = toGregorian day
firstmonthofquarter m = ((m-1) `div` 3) * 3 + 1
thisyear = startofyear
prevyear = startofyear . addGregorianYearsClip (-1)
nextyear = startofyear . addGregorianYearsClip 1
startofyear day = fromGregorian y 1 1 where (y,_,_) = toGregorian day
----------------------------------------------------------------------
-- parsing
firstJust ms = case dropWhile (==Nothing) ms of
[] -> Nothing
(md:_) -> md
-- | Parse a couple of date-time string formats to a time type.
parsedatetimeM :: String -> Maybe LocalTime
parsedatetimeM s = firstJust [
parseTime defaultTimeLocale "%Y/%m/%d %H:%M:%S" s,
parseTime defaultTimeLocale "%Y-%m-%d %H:%M:%S" s
]
-- | Parse a couple of date string formats to a time type.
parsedateM :: String -> Maybe Day
parsedateM s = firstJust [
parseTime defaultTimeLocale "%Y/%m/%d" s,
parseTime defaultTimeLocale "%Y-%m-%d" s
]
-- | Parse a date-time string to a time type, or raise an error.
parsedatetime :: String -> LocalTime
parsedatetime s = fromMaybe (error $ "could not parse timestamp \"" ++ s ++ "\"")
(parsedatetimeM s)
-- | Parse a date string to a time type, or raise an error.
parsedate :: String -> Day
parsedate s = fromMaybe (error $ "could not parse date \"" ++ s ++ "\"")
(parsedateM s)
-- | Parse a time string to a time type using the provided pattern, or
-- return the default.
parsetimewith :: ParseTime t => String -> String -> t -> t
parsetimewith pat s def = fromMaybe def $ parseTime defaultTimeLocale pat s
{-|
Parse a date in any of the formats allowed in ledger's period expressions,
and maybe some others:
> 2004
> 2004/10
> 2004/10/1
> 10/1
> 21
> october, oct
> yesterday, today, tomorrow
> (not yet) this/next/last week/day/month/quarter/year
Returns a SmartDate, to be converted to a full date later (see fixSmartDate).
Assumes any text in the parse stream has been lowercased.
-}
smartdate :: GenParser Char st SmartDate
smartdate = do
-- XXX maybe obscures date errors ? see ledgerdate
(y,m,d) <- choice' [yyyymmdd, ymd, ym, md, y, d, month, mon, today, yesterday, tomorrow, lastthisnextthing]
return (y,m,d)
-- | Like smartdate, but there must be nothing other than whitespace after the date.
smartdateonly :: GenParser Char st SmartDate
smartdateonly = do
d <- smartdate
many spacenonewline
eof
return d
datesepchars = "/-."
datesepchar = oneOf datesepchars
validYear, validMonth, validDay :: String -> Bool
validYear s = length s >= 4 && isJust (readMay s :: Maybe Int)
validMonth s = maybe False (\n -> n>=1 && n<=12) $ readMay s
validDay s = maybe False (\n -> n>=1 && n<=31) $ readMay s
-- failIfInvalidYear, failIfInvalidMonth, failIfInvalidDay :: a
failIfInvalidYear s = unless (validYear s) $ fail $ "bad year number: " ++ s
failIfInvalidMonth s = unless (validMonth s) $ fail $ "bad month number: " ++ s
failIfInvalidDay s = unless (validDay s) $ fail $ "bad day number: " ++ s
yyyymmdd :: GenParser Char st SmartDate
yyyymmdd = do
y <- count 4 digit
m <- count 2 digit
failIfInvalidMonth m
d <- count 2 digit
failIfInvalidDay d
return (y,m,d)
ymd :: GenParser Char st SmartDate
ymd = do
y <- many1 digit
failIfInvalidYear y
datesepchar
m <- many1 digit
failIfInvalidMonth m
datesepchar
d <- many1 digit
failIfInvalidDay d
return $ (y,m,d)
ym :: GenParser Char st SmartDate
ym = do
y <- many1 digit
failIfInvalidYear y
datesepchar
m <- many1 digit
failIfInvalidMonth m
return (y,m,"")
y :: GenParser Char st SmartDate
y = do
y <- many1 digit
failIfInvalidYear y
return (y,"","")
d :: GenParser Char st SmartDate
d = do
d <- many1 digit
failIfInvalidDay d
return ("","",d)
md :: GenParser Char st SmartDate
md = do
m <- many1 digit
failIfInvalidMonth m
datesepchar
d <- many1 digit
failIfInvalidDay d
return ("",m,d)
months = ["january","february","march","april","may","june",
"july","august","september","october","november","december"]
monthabbrevs = ["jan","feb","mar","apr","may","jun","jul","aug","sep","oct","nov","dec"]
weekdays = ["monday","tuesday","wednesday","thursday","friday","saturday","sunday"]
weekdayabbrevs = ["mon","tue","wed","thu","fri","sat","sun"]
monthIndex s = maybe 0 (+1) $ lowercase s `elemIndex` months
monIndex s = maybe 0 (+1) $ lowercase s `elemIndex` monthabbrevs
month :: GenParser Char st SmartDate
month = do
m <- choice $ map (try . string) months
let i = monthIndex m
return ("",show i,"")
mon :: GenParser Char st SmartDate
mon = do
m <- choice $ map (try . string) monthabbrevs
let i = monIndex m
return ("",show i,"")
today,yesterday,tomorrow :: GenParser Char st SmartDate
today = string "today" >> return ("","","today")
yesterday = string "yesterday" >> return ("","","yesterday")
tomorrow = string "tomorrow" >> return ("","","tomorrow")
lastthisnextthing :: GenParser Char st SmartDate
lastthisnextthing = do
r <- choice [
string "last"
,string "this"
,string "next"
]
many spacenonewline -- make the space optional for easier scripting
p <- choice [
string "day"
,string "week"
,string "month"
,string "quarter"
,string "year"
]
-- XXX support these in fixSmartDate
-- ++ (map string $ months ++ monthabbrevs ++ weekdays ++ weekdayabbrevs)
return ("",r,p)
periodexpr :: Day -> GenParser Char st (Interval, DateSpan)
periodexpr rdate = choice $ map try [
intervalanddateperiodexpr rdate,
intervalperiodexpr,
dateperiodexpr rdate,
(return (NoInterval,DateSpan Nothing Nothing))
]
intervalanddateperiodexpr :: Day -> GenParser Char st (Interval, DateSpan)
intervalanddateperiodexpr rdate = do
many spacenonewline
i <- periodexprinterval
many spacenonewline
s <- periodexprdatespan rdate
return (i,s)
intervalperiodexpr :: GenParser Char st (Interval, DateSpan)
intervalperiodexpr = do
many spacenonewline
i <- periodexprinterval
return (i, DateSpan Nothing Nothing)
dateperiodexpr :: Day -> GenParser Char st (Interval, DateSpan)
dateperiodexpr rdate = do
many spacenonewline
s <- periodexprdatespan rdate
return (NoInterval, s)
periodexprinterval :: GenParser Char st Interval
periodexprinterval =
choice $ map try [
tryinterval "day" "daily" Daily,
tryinterval "week" "weekly" Weekly,
tryinterval "month" "monthly" Monthly,
tryinterval "quarter" "quarterly" Quarterly,
tryinterval "year" "yearly" Yearly
]
where
tryinterval s1 s2 v =
choice [try (string $ "every "++s1), try (string s2)] >> return v
periodexprdatespan :: Day -> GenParser Char st DateSpan
periodexprdatespan rdate = choice $ map try [
doubledatespan rdate,
fromdatespan rdate,
todatespan rdate,
justdatespan rdate
]
doubledatespan :: Day -> GenParser Char st DateSpan
doubledatespan rdate = do
optional (string "from" >> many spacenonewline)
b <- smartdate
many spacenonewline
optional (string "to" >> many spacenonewline)
e <- smartdate
return $ DateSpan (Just $ fixSmartDate rdate b) (Just $ fixSmartDate rdate e)
fromdatespan :: Day -> GenParser Char st DateSpan
fromdatespan rdate = do
string "from" >> many spacenonewline
b <- smartdate
return $ DateSpan (Just $ fixSmartDate rdate b) Nothing
todatespan :: Day -> GenParser Char st DateSpan
todatespan rdate = do
string "to" >> many spacenonewline
e <- smartdate
return $ DateSpan Nothing (Just $ fixSmartDate rdate e)
justdatespan :: Day -> GenParser Char st DateSpan
justdatespan rdate = do
optional (string "in" >> many spacenonewline)
d <- smartdate
return $ spanFromSmartDate rdate d
mkdatespan :: String -> String -> DateSpan
mkdatespan b = DateSpan (Just $ parsedate b) . Just . parsedate
nulldatespan = DateSpan Nothing Nothing
nulldate = parsedate "1900/01/01"
tests_Dates = TestList [
"splitSpan" ~: do
let gives (interval, span) = (splitSpan interval span `is`)
(NoInterval,mkdatespan "2008/01/01" "2009/01/01") `gives`
[mkdatespan "2008/01/01" "2009/01/01"]
(Quarterly,mkdatespan "2008/01/01" "2009/01/01") `gives`
[mkdatespan "2008/01/01" "2008/04/01"
,mkdatespan "2008/04/01" "2008/07/01"
,mkdatespan "2008/07/01" "2008/10/01"
,mkdatespan "2008/10/01" "2009/01/01"
]
(Quarterly,nulldatespan) `gives`
[nulldatespan]
(Daily,mkdatespan "2008/01/01" "2008/01/01") `gives`
[mkdatespan "2008/01/01" "2008/01/01"]
(Quarterly,mkdatespan "2008/01/01" "2008/01/01") `gives`
[mkdatespan "2008/01/01" "2008/01/01"]
]