-- Generates tables from CSV files.
--
-- I wrote it specifically to make pretty Unicode tables like this:
-- 
-- ┌─────┬─────┬─────┐
-- │ foo │ bar │ baz │
-- ├─────┼─────┼─────┤
-- │ boo │ baa │ bee │
-- │ haa │ hee │ hoo │
-- └─────┴─────┴─────┘
--
-- It always treats the first record as the column headers.

module Main where

import System.Environment
import System.IO
import System.Console.GetOpt

import Converter
import Utilities
import Unicode
import HTML
import TBL
import ASCII
import CSV
import LaTeX
import ConTeXt

version :: Double
version = 0.8

data Options = Options 
    { optHelp        :: Bool
    , optVersion     :: Bool
    , optConverter   :: Converter
    }

defaultOptions :: Options
defaultOptions = Options
    { optHelp      = False
    , optVersion   = False
    , optConverter = HTML.converter
    }

converters :: [Converter]
converters = 
    [ ASCII.converter
    , HTML.converter
    , TBL.converter
    , Unicode.converter
    , LaTeX.converter
    , ConTeXt.converter]

usage :: String
usage = "Usage: tablify [OPTION...] file"

options :: [OptDescr (Options -> Options)]
options = 
    [ Option "v"  ["version"] 
        (NoArg (\o -> o { optVersion = True }))
        "show version"
    , Option "h"  ["help"] 
        (NoArg (\o -> o { optHelp = True }))
        "show this help" ] ++ moreOptions
    where
        moreOptions = map converterToOption converters
        converterToOption c@(Converter name _ short long) = 
            Option short [long] 
                (NoArg (\o -> o {optConverter = c}))
                ("output " ++ name ++ " table")

getOptions :: [String] -> IO (Options, [String])
getOptions argv =
    case getOpt Permute options argv of
        (o, n, []) -> return (foldl (flip id) defaultOptions o, n)
        (_, _, errors) -> ioError (userError 
                            (concat errors ++ usageInfo usage options))

processOpts :: Table -> Options -> String
processOpts table (Options _ _ (Converter { cConvert = f })) = f table
        
parseData :: String -> IO Table
parseData dat = case parseCSV dat of 
    Left _ -> ioError $ userError "unable to parse file"
    Right result -> return result

processFile :: Options -> String -> IO ()
processFile opts file = do
    fileData <- if file == "-" then getContents    else readFile file
    table <- parseData fileData
    putStrLn $ processOpts table opts

showInfo :: Options -> IO ()
showInfo Options { optVersion = True } = putStrLn $ "tablify version " ++ show version
showInfo Options { optHelp = True }    = putStr $ usageInfo usage options
showInfo _                             = fail "unable to show info for weird options"

main :: IO ()
main = do
    args <- getArgs
    (opts, arguments) <- getOptions args
    hSetEncoding stdout utf8
    if optHelp opts || optVersion opts 
        then showInfo opts
        else mapM_ (processFile opts) arguments