reploy/site.hs
2023-05-23 23:06:18 +02:00

161 lines
4.6 KiB
Haskell

{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE OverloadedStrings #-}
import Control.Monad (unless, when)
import Control.Monad.IO.Class
import Control.Monad.Trans.State.Lazy
import Data.Default (def)
import Data.Foldable (traverse_)
import Data.List (nub)
import Data.List.Extra (stripSuffix)
import qualified Data.Map as M
import Data.Maybe (fromMaybe, isJust)
import Data.String (fromString)
import qualified Data.Text as T
import qualified Data.Text.Encoding
import qualified Data.Text.IO as TIO
import qualified Data.Yaml as Y
import Hakyll.Core.Util.File (getRecursiveContents, makeDirectories)
import Lens.Micro
import Lens.Micro.Aeson
import Lens.Micro.Mtl
import Lens.Micro.TH
import System.Environment (getArgs)
import System.FilePath ((</>), splitPath)
import qualified Text.Mustache as Mu
import Text.Pandoc.Class (runIOorExplode)
import qualified Text.Pandoc.Definition
import qualified Text.Pandoc.Extensions
import Text.Pandoc.Options (ReaderOptions(..))
import Text.Pandoc.Readers.Markdown (readMarkdown)
import Debug.Trace
io :: MonadIO m => IO a -> m a
io = liftIO
just _ (Just val) = val
just err Nothing = error ("Missing: " ++ err)
data PageInfo =
PageInfo
{ _pagePath :: FilePath
, _pageMeta :: Y.Value
, _pagePandoc :: Text.Pandoc.Definition.Pandoc
}
deriving (Show)
makeLenses ''PageInfo
data SiteState =
SiteState
{ _pages :: M.Map FilePath PageInfo
, _redirects :: M.Map FilePath FilePath -- from -> to
, _htags :: M.Map [String] [FilePath] -- tag sequence -> tagged locs
, _installs :: M.Map FilePath FilePath -- file hash -> install location
, _templates :: M.Map FilePath Mu.Template -- TODO mustache templates
, _outputDir :: FilePath
, _defaultTemplate :: FilePath
}
deriving (Show)
makeLenses ''SiteState
emptySiteState out =
SiteState
{ _pages = M.empty
, _redirects = M.empty
, _htags = M.empty
, _installs = M.empty
, _templates = M.empty
, _outputDir = out
, _defaultTemplate = "default.html"
}
type Site a = StateT SiteState IO a
hasSuffix s = isJust . stripSuffix s
sourcePages :: FilePath -> Site ()
sourcePages fp = do
links <-
io $ filter (hasSuffix ".md" . last . splitPath) <$>
getRecursiveContents (pure . const False) fp
traverse_ loadPage (map (fp </>) links)
markdownReadOpts =
def
{ readerExtensions =
Text.Pandoc.Extensions.enableExtension
Text.Pandoc.Extensions.Ext_smart
Text.Pandoc.Extensions.pandocExtensions
}
loadPage :: FilePath -> Site ()
loadPage fp = do
txt <- io $ TIO.readFile fp
(T.take 4 txt == "---\n") `unless`
error ("metadata block start missing in " ++ fp)
let (meta, markdown) = T.breakOn "\n---\n" (T.drop 4 txt)
T.null meta `when` error ("metadata block bad in " ++ fp)
yml <- Y.decodeThrow $ Data.Text.Encoding.encodeUtf8 meta
md <- io $ runIOorExplode $ readMarkdown markdownReadOpts (T.drop 5 markdown)
let mount =
T.unpack . just ("mount point of " ++ fp) $ yml ^? key "title" . _String
pages %=
M.insert mount PageInfo {_pagePath = fp, _pageMeta = yml, _pagePandoc = md}
pageTemplate :: PageInfo -> Site FilePath
pageTemplate pi = do
dt <- use defaultTemplate
pure . maybe dt T.unpack $ pi ^? pageMeta . key "template" . _String
pageTemplates :: Site [FilePath]
pageTemplates = nub <$> (gets (^.. pages . traverse) >>= traverse pageTemplate)
sourceTemplates :: FilePath -> Site ()
sourceTemplates templdir = do
ts <- pageTemplates
templs' <- fmap sequence . traverse (io . Mu.automaticCompile [templdir]) $ ts
case templs' of
Left err -> error $ "template compilation: " ++ show err
Right templs -> templates .= M.fromList (zip ts templs)
indexFilename :: FilePath -> Site FilePath
indexFilename mount = do
od <- use outputDir
pure (od </> mount </> "index.html")
installPage :: FilePath -> PageInfo -> Site ()
installPage mount pi = do
tname <- fromString <$> pageTemplate pi
templ <- use $ templates . to (M.! tname)
file <- indexFilename mount
io $ do
putStrLn $ ">>> " ++ file
makeDirectories file
TIO.writeFile file . Mu.substitute templ $ pi ^. pageMeta
installFile :: FilePath -> Site FilePath
installFile = undefined
makeRedirect :: FilePath -> FilePath -> Site ()
makeRedirect = undefined
makeRedirects :: Site ()
makeRedirects = undefined
renderTag :: [String] -> Site ()
renderTag = undefined
renderTags :: Site ()
renderTags = undefined
main = do
[targetDir] <- getArgs
flip runStateT (emptySiteState targetDir) $ do
traverse sourcePages ["external"]
sourceTemplates "templates"
use pages >>= traverse (uncurry installPage) . M.assocs
get >>= io . print