hledger/hledger-lib/Hledger/Data/AccountName.hs
2011-06-11 18:35:20 +00:00

225 lines
8.6 KiB
Haskell

{-# LANGUAGE NoMonomorphismRestriction#-}
{-|
'AccountName's are strings like @assets:cash:petty@, with multiple
components separated by ':'. From a set of these we derive the account
hierarchy.
-}
module Hledger.Data.AccountName
where
import Data.List
import Data.Map (Map)
import Data.Tree
import Test.HUnit
import Text.Printf
import qualified Data.Map as M
import Hledger.Data.Types
import Hledger.Utils
-- change to use a different separator for nested accounts
acctsepchar = ':'
accountNameComponents :: AccountName -> [String]
accountNameComponents = splitAtElement acctsepchar
accountNameFromComponents :: [String] -> AccountName
accountNameFromComponents = concat . intersperse [acctsepchar]
accountLeafName :: AccountName -> String
accountLeafName = last . accountNameComponents
accountNameLevel :: AccountName -> Int
accountNameLevel "" = 0
accountNameLevel a = length (filter (==acctsepchar) a) + 1
accountNameDrop :: Int -> AccountName -> AccountName
accountNameDrop n = accountNameFromComponents . drop n . accountNameComponents
-- | ["a:b:c","d:e"] -> ["a","a:b","a:b:c","d","d:e"]
expandAccountNames :: [AccountName] -> [AccountName]
expandAccountNames as = nub $ concatMap expand as
where expand = map accountNameFromComponents . tail . inits . accountNameComponents
-- | ["a:b:c","d:e"] -> ["a","d"]
topAccountNames :: [AccountName] -> [AccountName]
topAccountNames as = [a | a <- expandAccountNames as, accountNameLevel a == 1]
parentAccountName :: AccountName -> AccountName
parentAccountName = accountNameFromComponents . init . accountNameComponents
parentAccountNames :: AccountName -> [AccountName]
parentAccountNames a = parentAccountNames' $ parentAccountName a
where
parentAccountNames' "" = []
parentAccountNames' a = a : parentAccountNames' (parentAccountName a)
isAccountNamePrefixOf :: AccountName -> AccountName -> Bool
isAccountNamePrefixOf = isPrefixOf . (++ [acctsepchar])
isSubAccountNameOf :: AccountName -> AccountName -> Bool
s `isSubAccountNameOf` p =
(p `isAccountNamePrefixOf` s) && (accountNameLevel s == (accountNameLevel p + 1))
-- | From a list of account names, select those which are direct
-- subaccounts of the given account name.
subAccountNamesFrom :: [AccountName] -> AccountName -> [AccountName]
subAccountNamesFrom accts a = filter (`isSubAccountNameOf` a) accts
-- | Convert a list of account names to a tree.
accountNameTreeFrom :: [AccountName] -> Tree AccountName
accountNameTreeFrom = accountNameTreeFrom1
accountNameTreeFrom1 accts =
Node "top" (accounttreesfrom (topAccountNames accts))
where
accounttreesfrom :: [AccountName] -> [Tree AccountName]
accounttreesfrom [] = []
accounttreesfrom as = [Node a (accounttreesfrom $ subs a) | a <- as]
subs = subAccountNamesFrom (expandAccountNames accts)
nullaccountnametree = Node "top" []
accountNameTreeFrom2 accts =
Node "top" $ unfoldForest (\a -> (a, subs a)) $ topAccountNames accts
where
subs = subAccountNamesFrom allaccts
allaccts = expandAccountNames accts
-- subs' a = subsmap ! a
-- subsmap :: Map AccountName [AccountName]
-- subsmap = Data.Map.fromList [(a, subAccountNamesFrom allaccts a) | a <- allaccts]
accountNameTreeFrom3 accts =
Node "top" $ forestfrom allaccts $ topAccountNames accts
where
-- drop accts from the list of potential subs as we add them to the tree
forestfrom :: [AccountName] -> [AccountName] -> Forest AccountName
forestfrom subaccts accts =
[let subaccts' = subaccts \\ accts in Node a $ forestfrom subaccts' (subAccountNamesFrom subaccts' a) | a <- accts]
allaccts = expandAccountNames accts
-- a more efficient tree builder from Cale Gibbard
newtype Tree' a = T (Map a (Tree' a))
deriving (Show, Eq, Ord)
mergeTrees :: (Ord a) => Tree' a -> Tree' a -> Tree' a
mergeTrees (T m) (T m') = T (M.unionWith mergeTrees m m')
emptyTree = T M.empty
pathtree :: [a] -> Tree' a
pathtree [] = T M.empty
pathtree (x:xs) = T (M.singleton x (pathtree xs))
fromPaths :: (Ord a) => [[a]] -> Tree' a
fromPaths = foldl' mergeTrees emptyTree . map pathtree
-- the above, but trying to build Tree directly
-- mergeTrees' :: (Ord a) => Tree a -> Tree a -> Tree a
-- mergeTrees' (Node m ms) (Node m' ms') = Node undefined (ms `union` ms')
-- emptyTree' = Node "top" []
-- pathtree' :: [a] -> Tree a
-- pathtree' [] = Node undefined []
-- pathtree' (x:xs) = Node x [pathtree' xs]
-- fromPaths' :: (Ord a) => [[a]] -> Tree a
-- fromPaths' = foldl' mergeTrees' emptyTree' . map pathtree'
-- converttree :: [AccountName] -> Tree' AccountName -> [Tree AccountName]
-- converttree parents (T m) = [Node (accountNameFromComponents $ parents ++ [a]) (converttree (parents++[a]) b) | (a,b) <- M.toList m]
-- accountNameTreeFrom4 :: [AccountName] -> Tree AccountName
-- accountNameTreeFrom4 accts = Node "top" (converttree [] $ fromPaths $ map accountNameComponents accts)
converttree :: Tree' AccountName -> [Tree AccountName]
converttree (T m) = [Node a (converttree b) | (a,b) <- M.toList m]
expandTreeNames :: Tree AccountName -> Tree AccountName
expandTreeNames (Node x ts) = Node x (map (treemap (\n -> accountNameFromComponents [x,n]) . expandTreeNames) ts)
accountNameTreeFrom4 :: [AccountName] -> Tree AccountName
accountNameTreeFrom4 = Node "top" . map expandTreeNames . converttree . fromPaths . map accountNameComponents
-- | Elide an account name to fit in the specified width.
-- From the ledger 2.6 news:
--
-- @
-- What Ledger now does is that if an account name is too long, it will
-- start abbreviating the first parts of the account name down to two
-- letters in length. If this results in a string that is still too
-- long, the front will be elided -- not the end. For example:
--
-- Expenses:Cash ; OK, not too long
-- Ex:Wednesday:Cash ; "Expenses" was abbreviated to fit
-- Ex:We:Afternoon:Cash ; "Expenses" and "Wednesday" abbreviated
-- ; Expenses:Wednesday:Afternoon:Lunch:Snack:Candy:Chocolate:Cash
-- ..:Af:Lu:Sn:Ca:Ch:Cash ; Abbreviated and elided!
-- @
elideAccountName :: Int -> AccountName -> AccountName
elideAccountName width s =
elideLeft width $ accountNameFromComponents $ elideparts width [] $ accountNameComponents s
where
elideparts :: Int -> [String] -> [String] -> [String]
elideparts width done ss
| length (accountNameFromComponents $ done++ss) <= width = done++ss
| length ss > 1 = elideparts width (done++[take 2 $ head ss]) (tail ss)
| otherwise = done++ss
clipAccountName :: Int -> AccountName -> AccountName
clipAccountName n = accountNameFromComponents . take n . accountNameComponents
-- | Convert an account name to a regular expression matching it and its subaccounts.
accountNameToAccountRegex :: String -> String
accountNameToAccountRegex "" = ""
accountNameToAccountRegex a = printf "^%s(:|$)" a
-- | Convert an account name to a regular expression matching it and its subaccounts.
accountNameToAccountOnlyRegex :: String -> String
accountNameToAccountOnlyRegex "" = ""
accountNameToAccountOnlyRegex a = printf "^%s$" a
-- | Convert an exact account-matching regular expression to a plain account name.
accountRegexToAccountName :: String -> String
accountRegexToAccountName = regexReplace "^\\^(.*?)\\(:\\|\\$\\)$" "\\1"
-- | Does this string look like an exact account-matching regular expression ?
isAccountRegex :: String -> Bool
isAccountRegex s = take 1 s == "^" && (take 5 $ reverse s) == ")$|:("
tests_Hledger_Data_AccountName = TestList
[
"accountNameTreeFrom" ~: do
accountNameTreeFrom ["a"] `is` Node "top" [Node "a" []]
accountNameTreeFrom ["a","b"] `is` Node "top" [Node "a" [], Node "b" []]
accountNameTreeFrom ["a","a:b"] `is` Node "top" [Node "a" [Node "a:b" []]]
accountNameTreeFrom ["a:b:c"] `is` Node "top" [Node "a" [Node "a:b" [Node "a:b:c" []]]]
,"expandAccountNames" ~:
expandAccountNames ["assets:cash","assets:checking","expenses:vacation"] `is`
["assets","assets:cash","assets:checking","expenses","expenses:vacation"]
,"isAccountNamePrefixOf" ~: do
"assets" `isAccountNamePrefixOf` "assets" `is` False
"assets" `isAccountNamePrefixOf` "assets:bank" `is` True
"assets" `isAccountNamePrefixOf` "assets:bank:checking" `is` True
"my assets" `isAccountNamePrefixOf` "assets:bank" `is` False
,"isSubAccountNameOf" ~: do
"assets" `isSubAccountNameOf` "assets" `is` False
"assets:bank" `isSubAccountNameOf` "assets" `is` True
"assets:bank:checking" `isSubAccountNameOf` "assets" `is` False
"assets:bank" `isSubAccountNameOf` "my assets" `is` False
]