-- | This is a Cartel program used to generate the cabal file for
-- Cartel itself.
--
-- You should note in your comments which version of Cartel was used
-- when writing the Cartel program; in this case, I used version
-- 0.4.0.0.
--
-- There's no huge benefit to using Cartel for small programs or
-- libraries; indeed, Cartel itself is small so there's not much
-- benefit to using Cartel here other than for pedagogical and
-- testing purposes.  Cartel is most useful for big Cabal files with
-- lots of redundancy and dozens of modules.
module Main (main) where

-- Cartel exports a lot of names; by importing them qualified you
-- don't have to worry about clashing with your own names

import qualified Cartel as A

-- Package Dependencies
--
-- It can be useful to pull these out and define them in
-- top-level values, especially if your Cabal file has many
-- redundancies.  That way you can update version numbers in just
-- one place rather than throughout your Cabal file (forgetting to
-- update all these numbers is a major reason I wrote Cartel.)

base :: A.Package
base = A.closedOpen "base" [4,5,0,0] [4,8]

directory :: A.Package
directory = A.closedOpen "directory" [1,1,0,2] [1,3]

filepath :: A.Package
filepath = A.closedOpen "filepath" [1,3,0,0] [1,4]

time :: A.Package
time = A.closedOpen "time" [1,4] [1,5]

testedWith :: [(A.Compiler, A.ConstrTree)]
testedWith =
  let ghc v = (A.GHC, A.Leaf (A.Constraint EQ (A.Version v)))
  in map ghc [[7,4,1], [7,6,3], [7,8,2]]

-- The global package properties.  Build your properties from the
-- default 'properties' record rather than the 'Properties'
-- constructor to help future-proof your code.

properties :: A.Properties
properties = A.properties
  { A.prName = "cartel"
  , A.prVersion = A.Version [0,8,0,0]
  , A.prCabalVersion = (1, 14)
  , A.prBuildType = A.Simple
  , A.prLicense = A.BSD3
  , A.prLicenseFile = "LICENSE"
  , A.prLicenseFiles = []
  , A.prExtraSourceFiles =
    [ "README.md"
    , "genCabal.hs"
    , "current-versions.txt"
    , "minimum-versions.txt" ]
  , A.prTestedWith = testedWith
  , A.prCopyright = "2014 Omari Norman"
  , A.prAuthor = "Omari Norman"
  , A.prMaintainer = "omari@smileystation.com"
  , A.prStability = "Experimental"
  , A.prHomepage = "http://www.github.com/massysett/cartel"
  , A.prBugReports = "omari@smileystation.com"
  , A.prSynopsis = "Specify your Cabal files in Haskell"
  , A.prDescription =
      [ "By specifying Cabal files in Haskell, you have the power"
      , "of Haskell at your disposal to eliminate redundancies"
      , "and to programatically populate various fields."
      , ""
      , "See the documentation in the \"Cartel\" module for details."
      ]
  , A.prCategory = "Distribution"
  }

-- Definition for the library.  It takes a list of modules to export
-- as a parameter; this allows the Main function to use a function
-- to generate the list of modules rather than you having to specify
-- them in a duplicative, error-prone, and boring process.

library
  :: [String]
  -- ^ List of library modules to export
  -> A.Library
library ms = A.Library $
  [ A.LibExposedModules ms
  , A.LibExposed True
  ] 
  
  ++ map A.LibInfo

  [ A.BuildDepends [base, directory, filepath, time]
  , A.OtherModules ["Paths_cartel"]
  , A.Buildable True
  , A.GHCOptions ["-Wall"]
  , A.DefaultLanguage A.Haskell2010
  , A.HsSourceDirs ["lib"]
  ]


-- Generate the complete Cabal record

cabal
  :: [String]
  -- ^ List of library modules
  -> A.Cabal
cabal mods = A.cabal
  { A.cProperties = properties
  , A.cLibrary = Just $ library mods
  }

-- To see the result, just run "runhaskell genCabal.hs".  The result
-- is printed to standard output.

main :: IO ()
main = do
  modulesToExport <- A.modules "lib"
  A.render "genCabal.hs" $ cabal modulesToExport