{-# LANGUAGE DataKinds #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}

-- | Copyright: (c) 2021-2022 berberman
-- SPDX-License-Identifier: MIT
-- Maintainer: berberman <berberman@yandex.com>
-- Stability: experimental
-- Portability: portable
module NvFetcher.Core
  ( Core (..),
    coreRules,
    runPackage,
  )
where

import Data.Coerce (coerce)
import qualified Data.HashMap.Strict as HMap
import qualified Data.Text as T
import Development.Shake
import Development.Shake.FilePath
import Development.Shake.Rule
import NvFetcher.ExtractSrc
import NvFetcher.FetchRustGitDeps
import NvFetcher.GetGitCommitDate
import NvFetcher.NixFetcher
import NvFetcher.Nvchecker
import NvFetcher.Types
import NvFetcher.Types.ShakeExtras

-- | The core rule of nvchecker.
-- all rules are wired here.
coreRules :: Rules ()
coreRules = do
  nvcheckerRule
  prefetchRule
  extractSrcRule
  fetchRustGitDepsRule
  getGitCommitDateRule
  addBuiltinRule noLint noIdentity $ \(WithPackageKey (Core, pkg)) _ _ -> do
    -- it's important to always rerun
    -- since the package definition is not tracked at all
    alwaysRerun
    lookupPackage pkg >>= \case
      Nothing -> fail $ "Unkown package key: " <> show pkg
      Just
        Package
          { _pversion = CheckVersion versionSource options,
            _ppassthru = (PackagePassthru passthru),
            ..
          } -> do
          _prversion@(NvcheckerResult version _mOldV _isStale) <- checkVersion versionSource options pkg
          _prfetched <- prefetch (_pfetcher version) _pforcefetch
          buildDir <- getBuildDir
          -- extract src
          _prextract <-
            case _pextract of
              Just (PackageExtractSrc extract) -> do
                result <- HMap.toList <$> extractSrcs _prfetched extract
                Just . HMap.fromList
                  <$> sequence
                    [ do
                        -- write extracted files to build dir
                        -- and read them in nix using 'builtins.readFile'
                        writeFile' (buildDir </> path) (T.unpack v)
                        pure (k, T.pack path)
                      | (k, v) <- result,
                        let path =
                              "./"
                                <> T.unpack _pname
                                <> "-"
                                <> T.unpack (coerce version)
                                </> k
                    ]
              _ -> pure Nothing
          -- cargo locks
          _prcargolock <-
            case _pcargo of
              Just (PackageCargoLockFiles lockPath) -> do
                lockFiles <- HMap.toList <$> extractSrcs _prfetched lockPath
                result <- parallel $
                  flip fmap lockFiles $ \(lockPath, lockData) -> do
                    result <- fetchRustGitDeps _prfetched lockPath
                    let lockPath' =
                          T.unpack _pname
                            <> "-"
                            <> T.unpack (coerce version)
                            </> lockPath
                        lockPathNix = "./" <> T.pack lockPath'
                    -- similar to extract src, write lock file to build dir
                    writeFile' (buildDir </> lockPath') $ T.unpack lockData
                    pure (lockPath, (lockPathNix, result))
                pure . Just $ HMap.fromList result
              _ -> pure Nothing

          -- Only git version source supports git commit date
          _prgitdate <- case versionSource of
            Git {..} -> Just <$> getGitCommitDate _vurl (coerce version) _pgitdateformat
            _ -> pure Nothing

          -- update changelog
          -- always use on disk version
          mOldV <- getLastVersionOnDisk pkg
          case mOldV of
            Nothing ->
              recordVersionChange _pname Nothing version
            Just old
              | old /= version ->
                recordVersionChange _pname (Just old) version
            _ -> pure ()

          let _prpassthru = if HMap.null passthru then Nothing else Just passthru
              _prname = _pname
              _prpinned = _ppinned
          -- Since we don't save the previous result, we are not able to know if the result changes
          -- Depending on this rule leads to RunDependenciesChanged
          pure $ RunResult ChangedRecomputeDiff mempty PackageResult {..}

-- | 'Core' rule take a 'PackageKey', find the corresponding 'Package', and run all needed rules to get 'PackageResult'
runPackage :: PackageKey -> Action PackageResult
runPackage k = apply1 $ WithPackageKey (Core, k)