module Data.Duration
( humanReadableDuration
-- durations
, ms
, oneSecond
, minute
, hour
, day
, year
-- Retrieve
, getMs
, getSeconds
, getMinutes
, getHours
, getDays
, getYears
) where
-- | `humanReadableDuration` take some time in micro-seconds and render a human readable duration.
--
-- > let duration = 2 * ms + 3 * oneSecond + 2 * minute + 33*day + 2*year
-- > humanReadableDuration duration
-- > -- will return: "2 years 33 days 2 min 3s 32ms"
humanReadableDuration :: Int -> String
humanReadableDuration n
| n < oneSecond = let mi = getMs n in if mi > 0 then show mi ++ "ms" else ""
| n < minute = let s = getSeconds n in if s > 0 then show s ++ "s " ++ humanReadableDuration (n `rem` oneSecond) else ""
| n < hour = let m = getMinutes n in if m > 0 then show m ++ " min " ++ humanReadableDuration (n `rem` minute) else ""
| n < day = let h = getHours n in if h > 0 then show h ++ " hours " ++ humanReadableDuration (n `rem` hour) else ""
| n < year = let d = getDays n in if d > 0 then show d ++ " days " ++ humanReadableDuration (n `rem` day) else ""
| otherwise = let y = getYears n in if y > 0 then show y ++ " years " ++ humanReadableDuration (n `rem` year) else ""
--------------------------------------------------------------------------------
-- Durations
--------------------------------------------------------------------------------
-- | number of micro seconds in one millisecond
ms :: Int
ms = 1000
-- | number of micro seconds in one second
oneSecond :: Int
oneSecond = 1000 * ms
-- | number of micro seconds in one minute
minute :: Int
minute = 60 * oneSecond
-- | number of micro seconds in one hour
hour :: Int
hour = 60 * minute
-- | number of micro seconds in one day
day :: Int
day = 24 * hour
-- | number of micro seconds in one year
year :: Int
year = 365 * day
--------------------------------------------------------------------------------
-- Retrieve some durations
--------------------------------------------------------------------------------
-- | number of milli seconds given a duration in micro seconds
getMs :: Int -> Int
getMs n = n `div` ms
-- | number of seconds given a duration in micro seconds
getSeconds :: Int -> Int
getSeconds n = n `div` oneSecond
-- | number of minutes given a duration in micro seconds
getMinutes :: Int -> Int
getMinutes n = n `div` minute
-- | number of hours given a duration in micro seconds
getHours :: Int -> Int
getHours n = n `div` hour
-- | number of days given a duration in micro seconds
getDays :: Int -> Int
getDays n = n `div` day
-- | number of years given a duration in micro seconds
getYears :: Int -> Int
getYears n = n `div` year