table-layout-0.5.2.0: src/Text/Layout/Table.hs
-- | This module provides tools to layout text as grid or table. Besides basic
-- things like specifying column positioning, alignment on the same character
-- and length restriction it also provides advanced features like justifying
-- text and fancy tables with styling support.
--
-- == Some examples
-- Layouting text as a plain grid (given a list of rows):
--
-- >>> putStrLn $ layoutToString [["a", "b"], ["c", "d"]] (repeat def)
-- a b
-- c d
--
-- Fancy table without header:
--
-- >>> putStrLn $ layoutTableToString [rowGroup [["Jack", "184.74"]], rowGroup [["Jane", "162.2"]]] def [def , numCol] unicodeRoundS
-- ╭──────┬────────╮
-- │ Jack │ 184.74 │
-- ├──────┼────────┤
-- │ Jane │ 162.2 │
-- ╰──────┴────────╯
--
-- Fancy table with header:
--
-- >>> putStrLn $ layoutTableToString [ rowGroup [["A very long text", "0.42000000"]]
-- , rowGroup [["Short text", "100200.5"]]
-- ]
-- (Just (["Title", "Length"], repeat def))
-- [fixedLeftCol 20, column (fixed 10) center dotAlign def]
-- unicodeRoundS
-- ╭──────────────────────┬────────────╮
-- │ Title │ Length │
-- ╞══════════════════════╪════════════╡
-- │ A very long text │ 0.4200… │
-- ├──────────────────────┼────────────┤
-- │ Short text │ …200.5 │
-- ╰──────────────────────┴────────────╯
--
-- Using justified text and 'RowGroup's to group multiple rows together to form one cell:
--
-- >>> putStrLn $ layoutTableToString [rowGroup $ columnsAsGrid center [justifyText 50 txt, [show $ length txt]]]
-- (Just (["Text", "Length"], repeat def))
-- [fixedLeftCol 50, numCol]
-- asciiS
-- +----------------------------------------------------+--------+
-- | Text | Length |
-- +----------------------------------------------------+--------+
-- | Lorem ipsum dolor sit amet, consetetur sadipscing | |
-- | elitr, sed diam nonumy eirmod tempor invidunt ut | |
-- | labore et dolore magna aliquyam erat, sed diam | |
-- | voluptua. At vero eos et accusam et justo duo | 295 |
-- | dolores et ea rebum. Stet clita kasd gubergren, no | |
-- | sea takimata sanctus est Lorem ipsum dolor sit | |
-- | amet. | |
-- +----------------------------------------------------+--------+
{-# LANGUAGE RecordWildCards #-}
module Text.Layout.Table
( -- * Layout combinators
-- | Specify how a column is rendered with the combinators in this
-- section. Sensible default values are provided with 'def'.
module Data.Default.Class
-- ** Columns
, ColSpec
, column
, numCol
, fixedCol
, fixedLeftCol
-- ** Length of columns
, LenSpec
, expand
, fixed
, expandUntil
, fixedUntil
-- ** Positional alignment
, Position
, H
, left
, right
, center
-- ** Alignment of cells at characters
, AlignSpec
, noAlign
, charAlign
, predAlign
, dotAlign
-- ** Cut marks
, CutMark
, noCutMark
, singleCutMark
, doubleCutMark
, ellipsisCutMark
-- * Basic grid and table layout
, Row
, layoutToCells
, layoutToLines
, layoutToString
-- * Grid modification functions
, altLines
, checkeredCells
-- * Advanced table layout
, RowGroup
, rowGroup
, HeaderColSpec
, headerColumn
, layoutTableToLines
, layoutTableToString
-- * Text justification
-- $justify
, justify
, justifyText
, Col
, columnsAsGrid
, top
, bottom
, V
, justifyTextsAsGrid
, justifyWordListsAsGrid
-- * Table styles
, module Text.Layout.Table.Style
-- * Column modification functions
, pad
, trimOrPad
, align
, alignFixed
-- * Column modifaction primitives
-- | Render your own kind of tables with the following functions.
, ColModInfo
, widthCMI
, unalignedCMI
, ensureWidthCMI
, ensureWidthOfCMI
, columnModifier
, AlignInfo
, widthAI
, deriveColModInfos
, deriveAlignInfo
, OccSpec
) where
-- TODO AlignSpec: multiple alignment points - useful?
-- TODO RowGroup: optional: vertical group labels
-- TODO RowGroup: optional: provide extra layout for a RowGroup
-- TODO ColModInfo: provide a special version of ensureWidthOfCMI to force header visibility
-- TODO ColSpec: add some kind of combinator to construct ColSpec values (e.g. via Monoid, see optparse-applicative)
-- TODO move functions not related to direct end-user into Primitives
import qualified Control.Arrow as A
import Data.List
import Data.Maybe
import Data.Default.Class
import Data.Default.Instances.Base ()
import Text.Layout.Table.Justify
import Text.Layout.Table.Style
import Text.Layout.Table.Position.Internal
import Text.Layout.Table.Primitives.AlignSpec.Internal
import Text.Layout.Table.Primitives.Basic
import Text.Layout.Table.Primitives.Column
import Text.Layout.Table.Primitives.LenSpec.Internal
import Text.Layout.Table.Primitives.Occurence
import Text.Layout.Table.Internal
-------------------------------------------------------------------------------
-- Layout types and combinators
-------------------------------------------------------------------------------
-- | Align all text at the first dot from the left. This is most useful for
-- floating point numbers.
dotAlign :: AlignSpec
dotAlign = charAlign '.'
-- | Numbers are positioned on the right and aligned on the floating point dot.
numCol :: ColSpec
numCol = column def right dotAlign def
-- | Fixes the column length and positions according to the given 'Position'.
fixedCol :: Int -> Position H -> ColSpec
fixedCol l pS = column (fixed l) pS def def
-- | Fixes the column length and positions on the left.
fixedLeftCol :: Int -> ColSpec
fixedLeftCol i = fixedCol i left
-------------------------------------------------------------------------------
-- Single-cell layout functions.
-------------------------------------------------------------------------------
-- | Assume the given length is greater or equal than the length of the 'String'
-- passed. Pads the given 'String' accordingly, using the position specification.
--
-- >>> pad left 10 "foo"
-- "foo "
--
pad :: Position o -> Int -> String -> String
pad p = case p of
Start -> fillRight
Center -> fillCenter
End -> fillLeft
-- | If the given text is too long, the 'String' will be shortened according to
-- the position specification, also adds some dots to indicate that the column
-- has been trimmed in length, otherwise behaves like 'pad'.
--
-- >>> trimOrPad left (singleCutMark "..") 10 "A longer text."
-- "A longer.."
--
trimOrPad :: Position o -> CutMark -> Int -> String -> String
trimOrPad p = case p of
Start -> fitRightWith
Center -> fitCenterWith
End -> fitLeftWith
-- | Align a column by first finding the position to pad with and then padding
-- the missing lengths to the maximum value. If no such position is found, it
-- will align it such that it gets aligned before that position.
--
-- This function assumes:
--
-- > ai <> deriveAlignInfo s = ai
--
align :: OccSpec -> AlignInfo -> String -> String
align oS (AlignInfo l r) s = case splitAtOcc oS s of
(ls, rs) -> fillLeft l ls ++ case rs of
-- No alignment character found.
[] -> (if r == 0 then "" else spaces r)
_ -> fillRight r rs
-- | Aligns a column using a fixed width, fitting it to the width by either
-- filling or cutting while respecting the alignment.
alignFixed :: Position o -> CutMark -> Int -> OccSpec -> AlignInfo -> String -> String
alignFixed _ cms 0 _ _ _ = ""
alignFixed _ cms 1 _ _ s@(_ : (_ : _)) = applyMarkLeftWith cms " "
alignFixed p cms i oS ai@(AlignInfo l r) s =
let n = l + r - i
in case splitAtOcc oS s of
(ls, rs) -> case p of
Start ->
let remRight = r - n
in if remRight < 0
then fitRight (l + remRight) $ fillLeft l ls
else fitRight (l + remRight) $ fillLeft l ls ++ rs
End ->
let remLeft = l - n
in if remLeft < 0
then fitLeft (r + remLeft) $ fillRight r rs
else fitLeft (r + remLeft) $ ls ++ fillRight r rs
Center ->
{-
This is really complicated, maybe there can be found
something better.
First case l > r:
l
|<----'----->|
|<-----------x----->|
|--.-->|
r
c1 = (l + r) div 2
|
|<---'--->|<---.--->|
. |
. c2 = c1 + (l + r) mod 2
.
. d2 = d1 + i mod 2
. |
|<-.->|<-'-->|
|
d1 = i div 2
|<----.----->|
i
needed length on the left side:
l - c1 + d1
needed length on the right side:
d2 - (l - c1)
Second case l < r:
l
|<--'-->|
|<------x---------->|
|<----.---->|
r
c1 = (l + r) div 2
|
|<---'--->|<---.--->|
. |
. c2 = c1 + (l + r) mod 2
.
. d2 = d1 + i mod 2
. |
|<-.->|<-'-->|
|
d1 = i div 2
|<----.----->|
i
needed length on the left side:
d1 - (r - c2)
needed length on the right side:
(c1 - l) + d2
-}
let (c, remC) = (l + r) `divMod` 2
(d, remD) = i `divMod` 2
d2 = d + remD
c2 = c + remC
-- Note: widthL and widthR can be negative if there is no
-- width left and we need to further trim into the other
-- side.
(widthL, widthR) = if l > c
then (l - c2 + d, d2 - (l - c2))
else (d - (r - c), (c2 - l) + d2)
lenL = length ls
lenR = length rs
toCutLfromR = negate $ min 0 widthL
toCutRfromL = max 0 $ negate widthR
(markL, funL) = if lenL > widthL
then ( applyMarkLeft
, take (widthL - toCutRfromL) . drop (lenL - widthL)
)
else ( id
, fillLeft (widthL - toCutRfromL) . take (lenL - toCutRfromL)
)
(markR, funR) = if lenR > widthR
then (applyMarkRight, take widthR)
else (id , fillRight widthR)
in markL $ markR $ funL ls ++ drop toCutLfromR (funR rs)
where
fitRight = fitRightWith cms
fitLeft = fitLeftWith cms
applyMarkRight = applyMarkRightWith cms
applyMarkLeft = applyMarkLeftWith cms
-- | Specifies how a column should be modified.
data ColModInfo = FillAligned OccSpec AlignInfo
| FillTo Int
| FitTo Int (Maybe (OccSpec, AlignInfo))
-- | Private show function.
showCMI :: ColModInfo -> String
showCMI cmi = case cmi of
FillAligned oS ai -> "FillAligned .. " ++ showAI ai
FillTo i -> "FillTo " ++ show i
FitTo i _ -> "FitTo " ++ show i ++ ".."
-- | Get the exact width after the modification.
widthCMI :: ColModInfo -> Int
widthCMI cmi = case cmi of
FillAligned _ ai -> widthAI ai
FillTo maxLen -> maxLen
FitTo lim _ -> lim
-- | Remove alignment from a 'ColModInfo'. This is used to change alignment of
-- headers, while using the combined width information.
unalignedCMI :: ColModInfo -> ColModInfo
unalignedCMI cmi = case cmi of
FillAligned _ ai -> FillTo $ widthAI ai
FitTo i _ -> FitTo i Nothing
_ -> cmi
-- | Ensures that the modification provides a minimum width, but only if it is
-- not limited.
ensureWidthCMI :: Int -> Position H -> ColModInfo -> ColModInfo
ensureWidthCMI w pos cmi = case cmi of
FillAligned oS ai@(AlignInfo lw rw) ->
let neededW = w - widthAI ai
in if neededW <= 0
then cmi
else FillAligned oS $ case pos of
Start -> AlignInfo lw (rw + neededW)
End -> AlignInfo (lw + neededW) rw
Center -> let (q, r) = neededW `divMod` 2
in AlignInfo (q + lw) (q + rw + r)
FillTo maxLen -> FillTo (max maxLen w)
_ -> cmi
-- | Ensures that the given 'String' will fit into the modified columns.
ensureWidthOfCMI :: String -> Position H -> ColModInfo -> ColModInfo
ensureWidthOfCMI = ensureWidthCMI . length
-- | Generates a function which modifies a given 'String' according to
-- 'Text.Layout.Table.Position.Position', 'CutMark' and 'ColModInfo'.
columnModifier :: Position H -> CutMark -> ColModInfo -> (String -> String)
columnModifier pos cms lenInfo = case lenInfo of
FillAligned oS ai -> align oS ai
FillTo maxLen -> pad pos maxLen
FitTo lim mT ->
maybe (trimOrPad pos cms lim) (uncurry $ alignFixed pos cms lim) mT
-- TODO factor out
-- | Specifies the length before and after a letter.
data AlignInfo = AlignInfo Int Int
-- | Private show function.
showAI :: AlignInfo -> String
showAI (AlignInfo l r) = "AlignInfo " ++ show l ++ " " ++ show r
-- | The column width when using the 'AlignInfo'.
widthAI :: AlignInfo -> Int
widthAI (AlignInfo l r) = l + r
-- | Since determining a maximum in two directions is not possible, a 'Monoid'
-- instance is provided.
instance Monoid AlignInfo where
mempty = AlignInfo 0 0
mappend (AlignInfo ll lr) (AlignInfo rl rr) = AlignInfo (max ll rl) (max lr rr)
-- | Derive the 'ColModInfo' by using layout specifications and looking at the
-- cells.
deriveColModInfos :: [(LenSpec, AlignSpec)] -> [Row String] -> [ColModInfo]
deriveColModInfos specs = zipWith ($) (fmap fSel specs) . transpose
where
fSel (lenSpec, alignSpec) = case alignSpec of
NoAlign -> let fitTo i = const $ FitTo i Nothing
expandUntil f i max = if f (max <= i)
then FillTo max
else fitTo i max
fun = case lenSpec of
Expand -> FillTo
Fixed i -> fitTo i
ExpandUntil i -> expandUntil id i
FixedUntil i -> expandUntil not i
in fun . maximum . map length
AlignOcc oS -> let fitToAligned i = FitTo i . Just . (,) oS
fillAligned = FillAligned oS
expandUntil f i ai = if f (widthAI ai <= i)
then fillAligned ai
else fitToAligned i ai
fun = case lenSpec of
Expand -> fillAligned
Fixed i -> fitToAligned i
ExpandUntil i -> expandUntil id i
FixedUntil i -> expandUntil not i
in fun . foldMap (deriveAlignInfo oS)
-- | Generate the 'AlignInfo' of a cell using the 'OccSpec'.
deriveAlignInfo :: OccSpec -> String -> AlignInfo
deriveAlignInfo occSpec s = AlignInfo <$> length . fst <*> length . snd $ splitAtOcc occSpec s
-------------------------------------------------------------------------------
-- Basic layout
-------------------------------------------------------------------------------
-- | Modifies cells according to the given 'ColSpec'.
layoutToCells :: [Row String] -> [ColSpec] -> [Row String]
layoutToCells tab specs = zipWith apply tab
. repeat
. zipWith (uncurry columnModifier) (map (position A.&&& cutMark) specs)
$ deriveColModInfos (map (lenSpec A.&&& alignSpec) specs) tab
where
apply = zipWith $ flip ($)
-- | Behaves like 'layoutToCells' but produces lines by joining with whitespace.
layoutToLines :: [Row String] -> [ColSpec] -> [String]
layoutToLines tab specs = map unwords $ layoutToCells tab specs
-- | Behaves like 'layoutToCells' but produces a 'String' by joining with the
-- newline character.
layoutToString :: [Row String] -> [ColSpec] -> String
layoutToString tab specs = concatLines $ layoutToLines tab specs
-------------------------------------------------------------------------------
-- Grid modifier functions
-------------------------------------------------------------------------------
-- | Applies functions alternating to given lines. This makes it easy to color
-- lines to improve readability in a row.
altLines :: [a -> b] -> [a] -> [b]
altLines = zipWith ($) . cycle
-- | Applies functions alternating to cells for every line, every other line
-- gets shifted by one. This is useful for distinguishability of single cells in
-- a grid arrangement.
checkeredCells :: (a -> b) -> (a -> b) -> [[a]] -> [[b]]
checkeredCells f g = zipWith altLines $ cycle [[f, g], [g, f]]
-------------------------------------------------------------------------------
-- Advanced layout
-------------------------------------------------------------------------------
-- | Layouts a good-looking table with a optional header. Note that specifying
-- fewer layout specifications than columns or vice versa will result in not
-- showing them.
layoutTableToLines :: [RowGroup] -- ^ Groups
-> Maybe ([String], [HeaderColSpec]) -- ^ Optional header details
-> [ColSpec] -- ^ Layout specification of columns
-> TableStyle -- ^ Visual table style
-> [String]
layoutTableToLines rGs optHeaderInfo specs (TableStyle { .. }) =
topLine : addHeaderLines (rowGroupLines ++ [bottomLine])
where
-- Line helpers
vLine hs d = vLineDetail hs d d d
vLineDetail hS dL d dR cols = intercalate [hS] $ [dL] : intersperse [d] cols ++ [[dR]]
-- Spacers consisting of columns of seperator elements.
genHSpacers c = map (flip replicate c) colWidths
-- Vertical seperator lines
topLine = vLineDetail realTopH realTopL realTopC realTopR $ genHSpacers realTopH
bottomLine = vLineDetail groupBottomH groupBottomL groupBottomC groupBottomR $ genHSpacers groupBottomH
groupSepLine = vLineDetail groupSepH groupSepLC groupSepC groupSepRC $ genHSpacers groupSepH
headerSepLine = vLineDetail headerSepH headerSepLC headerSepC headerSepRC $ genHSpacers headerSepH
-- Vertical content lines
rowGroupLines = intercalate [groupSepLine] $ map (map (vLine ' ' groupV) . applyRowMods . rows) rGs
-- Optional values for the header
(addHeaderLines, fitHeaderIntoCMIs, realTopH, realTopL, realTopC, realTopR) = case optHeaderInfo of
Just (h, headerColSpecs) ->
let headerLine = vLine ' ' headerV (zipApply h headerRowMods)
headerRowMods = zipWith3 (\(HeaderColSpec pos optCutMark) cutMark ->
columnModifier pos $ fromMaybe cutMark optCutMark
)
headerColSpecs
cMSs
(map unalignedCMI cMIs)
in
( (headerLine :) . (headerSepLine :)
, zipWith ($) $ zipWith ($) (map ensureWidthOfCMI h) posSpecs
, headerTopH
, headerTopL
, headerTopC
, headerTopR
)
Nothing ->
( id
, id
, groupTopH
, groupTopL
, groupTopC
, groupTopR
)
cMSs = map cutMark specs
posSpecs = map position specs
applyRowMods xss = zipWith zipApply xss $ repeat rowMods
rowMods = zipWith3 columnModifier posSpecs cMSs cMIs
cMIs = fitHeaderIntoCMIs $ deriveColModInfos (map (lenSpec A.&&& alignSpec) specs)
$ concatMap rows rGs
colWidths = map widthCMI cMIs
zipApply = zipWith $ flip ($)
layoutTableToString :: [RowGroup]
-> Maybe ([String], [HeaderColSpec])
-> [ColSpec]
-> TableStyle
-> String
layoutTableToString rGs optHeaderInfo specs = concatLines . layoutTableToLines rGs optHeaderInfo specs
-------------------------------------------------------------------------------
-- Text justification
-------------------------------------------------------------------------------
-- $justify
-- Text can easily be justified and distributed over multiple lines. Such
-- columns can easily be combined with other columns.
--