#!/usr/bin/env cabal
{- cabal:
  build-depends:
    base == 4.*
    , turtle == 1.5.*
    , regex-tdfa == 1.3.*
    , text == 1.2.*
-}
{-# LANGUAGE OverloadedStrings #-}

import Control.Monad (when)
import qualified Data.Text as T
import qualified Data.Text.IO as T.IO
import System.Environment (getArgs)
import System.Exit (ExitCode (..))
import qualified Text.Regex.TDFA as TR
import Turtle (empty, shell, shellStrict)

main = do
  args <- getArgs
  case args of
    [version] -> makeNewRelease version
    _ -> putStrLn "Usage: new-release <version>"

makeNewRelease :: String -> IO ()
makeNewRelease newVersion = do
  (ExitSuccess, branchName) <- shellStrict "git rev-parse --abbrev-ref HEAD" empty
  when (T.strip branchName /= "release") $ error "You must run this script from the release branch!"

  let cabalFileName = "waspc.cabal"
  oldCabalFileContents <- T.unpack <$> T.IO.readFile cabalFileName

  (newCabalFileContents, oldVersion) <- updateCabalFile oldCabalFileContents newVersion
  let tag = "v" ++ newVersion

  when (newVersion == oldVersion) $ error "Version you provided is the current version!"

  putStrLn $
    unlines
      [ "This will update wasp version from " ++ oldVersion ++ " to " ++ newVersion,
        cabalFileName ++ " will be updated, and this change will be commited and pushed.",
        "Also, tag " ++ tag ++ " will be created and pushed, triggering CI to"
          ++ " create new release on Github.",
        "Are you sure you want to proceed (y/n)?"
      ]
  confirmation <- getLine
  when (confirmation /= "y") $ error "Aborting"

  T.IO.writeFile cabalFileName $ T.pack newCabalFileContents

  -- TODO: Print what I am doing for each step.

  putStrLn $ "\nCreating new commit with updated " ++ cabalFileName ++ " and pushing it.\n"
  ExitSuccess <- shell (T.pack $ "git add " ++ cabalFileName) empty
  ExitSuccess <- shell (T.pack $ "git commit -m \"Updated wasp version to " ++ newVersion ++ ".\"") empty
  gitPushExitCode <- shell "git push" empty
  case gitPushExitCode of
    ExitSuccess -> return ()
    ExitFailure _ -> do
      ExitSuccess <- shell "git reset --hard HEAD~1" empty
      error "Failed to do `git push`, reverted changes."

  putStrLn $ "\nCreating tag " ++ tag ++ " and pushing it.\n"
  ExitSuccess <- shell (T.pack $ "git tag " ++ tag) empty
  ExitSuccess <- shell (T.pack $ "git push origin " ++ tag) empty

  return ()

updateCabalFile :: String -> String -> IO (String, String) -- Returns (updated cabal file contents, old version)
updateCabalFile cabalFileContents newVersion = do
  let (beforeMatch, match, afterMatch, submatches) =
        cabalFileContents TR.=~ ("^(version: *)([0-9]+\\.[0-9]+\\.[0-9]+)" :: String) :: (String, String, String, [String])
  when (null match) $ error "Couldn't locate version in cabal file!?"
  let [matchBeforeVersion, oldVersion] = submatches
  let newContents = beforeMatch ++ matchBeforeVersion ++ newVersion ++ afterMatch
  return (newContents, oldVersion)