module Branches (
  activeBranches,
  fedoraBranches,
  fedoraBranchesNoMaster,
  isFedoraBranch,
  isEPELBranch,
  localBranches,
  pagurePkgBranches,
  mockConfig,
  module Distribution.Fedora.Branch,
  AnyBranch(..),
  anyBranch,
  isRelBranch,
  onlyRelBranch,
  BranchOpts(..),
  listOfBranches,
  gitCurrentBranch,
  systemBranch,
  getReleaseBranch
) where

import Common

import Distribution.Fedora.Branch
import SimpleCmd
import SimpleCmd.Git

import Pagure

data AnyBranch = RelBranch Branch | OtherBranch String
  deriving Eq

anyBranch :: String -> AnyBranch
anyBranch = either OtherBranch RelBranch . eitherBranch

-- allRelBranches :: [AnyBranch] -> Bool
-- allRelBranches = all isRelBranch

isRelBranch :: AnyBranch -> Bool
isRelBranch (RelBranch _) = True
isRelBranch _ = False

instance Show AnyBranch where
  show (RelBranch br) = show br
  show (OtherBranch obr) = obr

activeBranches :: [Branch] -> [String] -> [Branch]
activeBranches active =
  -- newest branch first
  reverse . sort . mapMaybe (readActiveBranch active)

fedoraBranches :: IO [String] -> IO [Branch]
fedoraBranches mthd = do
  active <- getFedoraBranches
  activeBranches active <$> mthd

fedoraBranchesNoMaster :: IO [String] -> IO [Branch]
fedoraBranchesNoMaster mthd = do
  active <- getFedoraBranched
  activeBranches active <$> mthd

isFedoraBranch :: Branch -> Bool
isFedoraBranch (Fedora _) = True
isFedoraBranch Master = True
isFedoraBranch _ = False

isEPELBranch :: Branch -> Bool
isEPELBranch (EPEL _) = True
isEPELBranch _ = False

localBranches :: IO [String]
localBranches = do
  origins <- filter ("origin/" `isPrefixOf`) <$> cmdLines "git" ["branch", "--remote", "--list", "--format=%(refname:lstrip=-2)"]
  return $ delete "HEAD" $ map (removePrefix "origin/") origins

pagurePkgBranches :: String -> IO [String]
pagurePkgBranches pkg = do
  let project = "rpms/" ++ pkg
  res <- pagureListGitBranches srcfpo project
  return $ either (error' . include project) id res
  where
    include p e = e ++ ": " ++ p

mockConfig :: Branch -> String
mockConfig Master = "fedora-rawhide-x86_64"
mockConfig (Fedora n) = "fedora-" ++ show n ++ "-x86_64"
mockConfig (EPEL n) = "epel-" ++ show n ++ "-x86_64"

------

data BranchOpts = AllBranches | AllFedora | AllEPEL | ExcludeBranches [Branch]
  deriving Eq

onlyRelBranch :: AnyBranch -> Branch
onlyRelBranch (RelBranch br) = br
onlyRelBranch (OtherBranch br) = error' $ "Non-release branch not allowed: " ++ br

systemBranch :: IO Branch
systemBranch =
  readBranch' . init . removePrefix "PLATFORM_ID=\"platform:" <$> cmd "grep" ["PLATFORM_ID=", "/etc/os-release"]

listOfBranches :: Bool -> Bool -> Maybe BranchOpts -> [AnyBranch] -> IO [AnyBranch]
listOfBranches _ _active (Just AllBranches) (_:_) =
  error' "cannot specify branches with --all-branches"
listOfBranches distgit _active (Just AllBranches) [] =
  if distgit
  then map RelBranch <$> fedoraBranches localBranches
  else error' "--all-branches only allowed for dist-git packages"
listOfBranches _ _active (Just AllFedora) (_:_) =
  error' "cannot specify branches with --all-fedora"
listOfBranches distgit _active (Just AllFedora) [] =
  if distgit
  then map RelBranch . filter isFedoraBranch <$> fedoraBranches localBranches
  else error' "--all-fedora only allowed for dist-git packages"
listOfBranches _ _active (Just AllEPEL) (_:_) =
  error' "cannot specify branches with --all-epel"
listOfBranches distgit _active (Just AllEPEL) [] =
  if distgit
  then map RelBranch . filter isEPELBranch <$> fedoraBranches localBranches
  else error' "--all-epel only allowed for dist-git packages"
listOfBranches distgit active Nothing brs =
  if null brs
  then
    pure <$> if distgit
             then gitCurrentBranch
             else RelBranch <$> systemBranch
  else do
    activeBrs <- getFedoraBranches
    forM_ brs $ \ br ->
      case br of
        RelBranch rbr -> do
          if active
            then when (rbr `notElem` activeBrs) $
                 error' $ show br ++ " is not an active branch"
            else
            case rbr of
              Fedora _ -> do
                let latest = maximum (delete Master activeBrs)
                when (rbr > latest) $
                  error' $ show rbr ++ " is newer than latest branch"
              -- FIXME also check for too new EPEL
              _ -> return ()
        _ -> return ()
    return brs
listOfBranches _ _ (Just (ExcludeBranches _)) (_:_) =
  error' "cannot specify branches with exclude-branch"
listOfBranches distgit _ (Just (ExcludeBranches brs)) [] = do
  branches <- if distgit
              then fedoraBranches localBranches
              else getFedoraBranches
  return $ map RelBranch (branches \\ brs)

getReleaseBranch :: IO Branch
getReleaseBranch = do
  mcurrent <- gitCurrentBranch
  case mcurrent of
    RelBranch br -> return br
    _ -> systemBranch

gitCurrentBranch :: IO AnyBranch
gitCurrentBranch =
  anyBranch <$> git "rev-parse" ["--abbrev-ref", "HEAD"]