module Distribution.Client.Dependency.Modular.ConfiguredConversion where

import Data.Maybe
import Prelude hiding (pi)

import Distribution.Client.Types
import Distribution.Client.Dependency.Types (ResolverPackage(..))
import qualified Distribution.Client.PackageIndex as CI
import qualified Distribution.Simple.PackageIndex as SI

import Distribution.Client.Dependency.Modular.Configured
import Distribution.Client.Dependency.Modular.Package

import Distribution.Client.ComponentDeps (ComponentDeps)


convCP :: SI.InstalledPackageIndex -> CI.PackageIndex SourcePackage ->
          CP QPN -> ResolverPackage
convCP iidx sidx (CP qpi fa es ds) =
  case convPI qpi of
    Left  pi -> PreExisting
                  (fromJust $ SI.lookupInstalledPackageId iidx pi)
    Right pi -> Configured $ ConfiguredPackage
                  (fromJust $ CI.lookupPackageId sidx pi)
                  fa
                  es
                  ds'
  where
    ds' :: ComponentDeps [ConfiguredId]
    ds' = fmap (map convConfId) ds

convPI :: PI QPN -> Either InstalledPackageId PackageId
convPI (PI _ (I _ (Inst pi))) = Left pi
convPI qpi                    = Right $ confSrcId $ convConfId qpi

convConfId :: PI QPN -> ConfiguredId
convConfId (PI (Q _ pn) (I v loc)) = ConfiguredId {
      confSrcId  = sourceId
    , confInstId = installedId
    }
  where
    sourceId    = PackageIdentifier pn v
    installedId = case loc of
                    Inst pi    -> pi
                    _otherwise -> fakeInstalledPackageId sourceId