{-# OPTIONS_GHC -fglasgow-exts #-}
module Main where

import Control.Monad
import Data.List
import Debian.Apt.Methods
import Debian.Report
import Debian.Repo.SourcesList
import Extra.Exit
import Extra.HaXml
import System.Environment
import Text.PrettyPrint.HughesPJ
import System.IO

-- * main

main :: IO ()
main =
    do (sourcesAFP, sourcesBFP) <- parseArgs
       let arch     = "i386" -- not actually used for anything right now, could be when binary package list is enabled
           cacheDir = "."    -- FIXME: replace with tempdir later
       sourcesA <- liftM parseSourcesList $ readFile sourcesAFP
       sourcesB <- liftM parseSourcesList $ readFile sourcesBFP
       trumpMap <- trumped (fetch emptyFetchCallbacks []) cacheDir arch sourcesA sourcesB
       print (showXML "trump.xsl" (trumpedXML trumpMap))

-- * command-line helper functions

helpText :: String -> Doc
helpText progName =
    (text "Usage:" <+> text progName <+> text "<old sources.list>" <+> text "<new sources.list>"$+$ 
     text [] $+$ 
     (fsep $ map text $ words $ "Find all the packages referenced by the second sources.list which trump packages find in the first sources.list.")
    )
    
parseArgs :: IO (String, String)
parseArgs =
    do args <- getArgs
       case args of
         [dista, distb] -> return (dista, distb)
         _ -> exitWithHelp helpText