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{-# LANGUAGE OverloadedStrings #-}

import Data.Monoid (mappend)
import qualified GHC.IO.Encoding as E
import Hakyll

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main :: IO ()
main = do
  E.setLocaleEncoding E.utf8
  hakyllWith config $ do
    match "images/*" $ do
      route idRoute
      compile copyFileCompiler

    match "css/*" $ compile compressCssCompiler
    create ["style.css"] $ do
      route idRoute
      compile $ do
        csses <- loadAll "css/*.css"
        makeItem $ unlines $ map itemBody csses

    match (fromList ["about.markdown", "resume.markdown"]) $ do
      route $ setExtension "html"
      compile $
        pandocCompiler
          >>= loadAndApplyTemplate "templates/default.html" defaultContext
          >>= relativizeUrls

    tags <- buildTags "posts/*" (fromCapture "tags/*.html")

    match "posts/*" $ do
      route $ setExtension "html"
      compile $
        pandocCompiler
          >>= loadAndApplyTemplate "templates/post.html" (postCtxWithTags tags)
          >>= loadAndApplyTemplate "templates/default.html" (postCtxWithTags tags)
          >>= relativizeUrls

    create ["archive.html"] $ do
      route idRoute
      compile $ do
        posts <- recentFirst =<< loadAll "posts/*"
        let archiveCtx =
              listField "posts" (postCtxWithTags tags) (return posts)
                `mappend` constField "title" "Archives"
                `mappend` defaultContext

        makeItem ""
          >>= loadAndApplyTemplate "templates/archive.html" archiveCtx
          >>= loadAndApplyTemplate "templates/default.html" archiveCtx
          >>= relativizeUrls

    match "index.html" $ do
      route idRoute
      compile $ do
        posts <- fmap (take 3) . recentFirst =<< loadAll "posts/*"
        let indexCtx =
              listField "posts" (postCtxWithTags tags) (return posts)
                `mappend` field "tags" (\_ -> renderTagList tags)
                `mappend` constField "title" "Welcome"
                `mappend` defaultContext

        getResourceBody
          >>= applyAsTemplate indexCtx
          >>= loadAndApplyTemplate "templates/default.html" indexCtx
          >>= relativizeUrls

    create ["sitemap.xml"] $ do
      route idRoute
      compile $ do
        posts <- recentFirst =<< loadAll "posts/*"
        let sitemapCtx =
              constField "baseUrl" "sanchayanmaity.net"
                `mappend` constField "title" "Sitemap"
                `mappend` listField "posts" (postCtxWithTags tags) (return posts)
                `mappend` postCtxWithTags tags

        makeItem ""
          >>= loadAndApplyTemplate "templates/sitemap.xml" sitemapCtx
          >>= cleanIndexHtmls

    match "templates/*" $ compile templateBodyCompiler

    tagsRules tags $ \tag pattern -> do
      let title = "Posts tagged \"" ++ tag ++ "\""
      route idRoute
      compile $ do
        posts <- recentFirst =<< loadAll pattern
        let ctx =
              constField "title" title
                `mappend` listField "posts" (postCtxWithTags tags) (return posts)
                `mappend` defaultContext

        makeItem ""
          >>= loadAndApplyTemplate "templates/tag.html" ctx
          >>= loadAndApplyTemplate "templates/default.html" ctx
          >>= relativizeUrls

--------------------------------------------------------------------------------
config :: Configuration
config =
  defaultConfiguration
    { destinationDirectory = "public"
    }

postCtx :: Context String
postCtx =
  dateField "date" "%B %e, %Y"
    `mappend` defaultContext

postCtxWithTags :: Tags -> Context String
postCtxWithTags tags = tagsField "tags" tags `mappend` postCtx

cleanIndexHtmls :: Item String -> Compiler (Item String)
cleanIndexHtmls = return . fmap (replaceAll pattern replacement)
  where
    pattern = "/index.html"

replacement :: String -> String
replacement = const "/"