hledger/Models.hs

222 lines
7.7 KiB
Haskell

module Models -- data types & behaviours
where
import Text.Printf
import Data.List
-- basic types
type Date = String
type Status = Bool
type Account = String
data Amount = Amount {
currency :: String,
quantity :: Double
} deriving (Eq)
-- amount arithmetic, ignores currency conversion
instance Num Amount where
abs (Amount c q) = Amount c (abs q)
signum (Amount c q) = Amount c (signum q)
fromInteger i = Amount "$" (fromInteger i)
(+) = amountAdd
(-) = amountSub
(*) = amountMult
Amount ca qa `amountAdd` Amount cb qb = Amount ca (qa + qb)
Amount ca qa `amountSub` Amount cb qb = Amount ca (qa - qb)
Amount ca qa `amountMult` Amount cb qb = Amount ca (qa * qb)
instance Show Amount where
show (Amount cur qty) =
let roundedqty = printf "%.2f" qty in
case roundedqty of
"0.00" -> "0"
otherwise -> cur ++ roundedqty
-- modifier & periodic entries
data ModifierEntry = ModifierEntry { -- aka "automated entry"
valueexpr :: String,
m_transactions :: [Transaction]
} deriving (Eq)
instance Show ModifierEntry where
show e = "= " ++ (valueexpr e) ++ "\n" ++ unlines (map show (m_transactions e))
data PeriodicEntry = PeriodicEntry {
periodexpr :: String,
p_transactions :: [Transaction]
} deriving (Eq)
instance Show PeriodicEntry where
show e = "~ " ++ (periodexpr e) ++ "\n" ++ unlines (map show (p_transactions e))
-- entries
-- a register entry is displayed as two or more lines like this:
-- date description account amount balance
-- DDDDDDDDDD dddddddddddddddddddd aaaaaaaaaaaaaaaaaaaaaaaaa AAAAAAAAAA AAAAAAAAAA
-- aaaaaaaaaaaaaaaaaaaaaaaaa AAAAAAAAAA AAAAAAAAAA
-- ... ... ...
-- dateWidth = 10
-- descWidth = 20
-- acctWidth = 25
-- amtWidth = 10
-- balWidth = 10
data Entry = Entry {
edate :: Date,
estatus :: Status,
ecode :: String,
edescription :: String,
etransactions :: [Transaction]
} deriving (Eq)
instance Show Entry where show = showEntryDetails
showEntryDetails e = printf "%-10s %-20s " (edate e) (take 20 $ edescription e)
isEntryBalanced :: Entry -> Bool
isEntryBalanced e = (sumTransactions . etransactions) e == 0
autofillEntry :: Entry -> Entry
autofillEntry e =
Entry (edate e) (estatus e) (ecode e) (edescription e)
(autofillTransactions (etransactions e))
-- transactions
data Transaction = Transaction {
taccount :: Account,
tamount :: Amount
} deriving (Eq)
instance Show Transaction where
show t = printf "%-25s %10s" (take 25 $ taccount t) (show $ tamount t)
autofillTransactions :: [Transaction] -> [Transaction]
autofillTransactions ts =
let (ns, as) = normalAndAutoTransactions ts in
case (length as) of
0 -> ns
1 -> ns ++ [balanceTransaction $ head as]
where balanceTransaction t = t{tamount = -(sumTransactions ns)}
otherwise -> error "too many blank transactions in this entry"
normalAndAutoTransactions :: [Transaction] -> ([Transaction], [Transaction])
normalAndAutoTransactions ts =
partition isNormal ts
where isNormal t = (currency $ tamount t) /= "AUTO"
sumTransactions :: [Transaction] -> Amount
sumTransactions ts = sum [tamount t | t <- ts]
-- entrytransactions
-- the entry/transaction types used in app-level functions have morphed
-- through E->T; (T,E); ET; E<->T; (E,T). Currently, we parse Entries
-- containing Transactions and flatten them into (Entry,Transaction) pairs
-- (hereafter referred to as "transactions") for processing
type EntryTransaction = (Entry,Transaction)
entry (e,t) = e
transaction (e,t) = t
date (e,t) = edate e
status (e,t) = estatus e
code (e,t) = ecode e
description (e,t) = edescription e
account (e,t) = taccount t
amount (e,t) = tamount t
flattenEntry :: Entry -> [EntryTransaction]
flattenEntry e = [(e,t) | t <- etransactions e]
entryTransactionsFrom :: [Entry] -> [EntryTransaction]
entryTransactionsFrom es = concat $ map flattenEntry es
matchTransactionAccount :: String -> EntryTransaction -> Bool
matchTransactionAccount s t = s `isInfixOf` (account t)
matchTransactionDescription :: String -> EntryTransaction -> Bool
matchTransactionDescription s t = s `isInfixOf` (description t)
showTransactionsWithBalances :: [EntryTransaction] -> Amount -> String
showTransactionsWithBalances [] _ = []
showTransactionsWithBalances ts b =
unlines $ showTransactionsWithBalances' ts dummyt b
where
dummyt = (Entry "" False "" "" [], Transaction "" (Amount "" 0))
showTransactionsWithBalances' [] _ _ = []
showTransactionsWithBalances' (t:ts) tprev b =
(if (entry t /= (entry tprev))
then [showTransactionDescriptionAndBalance t b']
else [showTransactionAndBalance t b'])
++ (showTransactionsWithBalances' ts t b')
where b' = b + (amount t)
showTransactionDescriptionAndBalance :: EntryTransaction -> Amount -> String
showTransactionDescriptionAndBalance t b =
(showTransactionEntryDetails t) ++ (showTransactionDetails t) ++ (showBalance b)
showTransactionAndBalance :: EntryTransaction -> Amount -> String
showTransactionAndBalance t b =
(replicate 32 ' ') ++ (showTransactionDetails t) ++ (showBalance b)
-- like showEntryDetails
showTransactionEntryDetails t = printf "%-10s %-20s " (date t) (take 20 $ description t)
showTransactionDetails t = printf "%-25s %10s" (take 25 $ account t) (show $ amount t)
showBalance b = printf " %10.2s" (show b)
-- accounts
accountsFromTransactions :: [EntryTransaction] -> [Account]
accountsFromTransactions ts = nub $ map account ts
-- ["a:b:c","d:e"] -> ["a","a:b","a:b:c","d","d:e"]
expandAccounts :: [Account] -> [Account]
expandAccounts l = nub $ concat $ map expand l
where
expand l' = map (concat . intersperse ":") (tail $ inits $ splitAtElement ':' l')
splitAtElement :: Eq a => a -> [a] -> [[a]]
splitAtElement e l =
case dropWhile (e==) l of
[] -> []
l' -> first : splitAtElement e rest
where
(first,rest) = break (e==) l'
-- ledger
data Ledger = Ledger {
modifier_entries :: [ModifierEntry],
periodic_entries :: [PeriodicEntry],
entries :: [Entry]
} deriving (Eq)
instance Show Ledger where
show l = "Ledger with " ++ m ++ " modifier, " ++ p ++ " periodic, " ++ e ++ " normal entries:\n"
++ (concat $ map show (modifier_entries l))
++ (concat $ map show (periodic_entries l))
++ (concat $ map show (entries l))
where
m = show $ length $ modifier_entries l
p = show $ length $ periodic_entries l
e = show $ length $ entries l
ledgerAccountsUsed :: Ledger -> [Account]
ledgerAccountsUsed l = accountsFromTransactions $ entryTransactionsFrom $ entries l
ledgerAccountTree :: Ledger -> [Account]
ledgerAccountTree = sort . expandAccounts . ledgerAccountsUsed
ledgerTransactions :: Ledger -> [EntryTransaction]
ledgerTransactions l = entryTransactionsFrom $ entries l
ledgerTransactionsMatching :: String -> Ledger -> [EntryTransaction]
ledgerTransactionsMatching s l = filter (\t -> matchTransactionAccount s t) (ledgerTransactions l)