From 47420cbe4169ebc2d5cd141e4da43fa3b2fd84ff Mon Sep 17 00:00:00 2001
From: "Niels G. W. Serup" <ngws@metanohi.name>
Date: Sat, 5 Oct 2024 18:07:26 +0200
Subject: [PATCH] Split template loading into multiple steps

---
 byg/src/DependencyGenerator.hs   | 16 ++++++++++------
 byg/src/Evaluation/Function.hs   |  5 +++++
 byg/src/Evaluation/FunctionIO.hs |  8 ++------
 byg/src/SiteGenerator.hs         |  2 +-
 byg/src/Types/Function.hs        |  1 +
 byg/src/Types/FunctionIO.hs      |  2 +-
 6 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/byg/src/DependencyGenerator.hs b/byg/src/DependencyGenerator.hs
index 4adc8db..82f860c 100644
--- a/byg/src/DependencyGenerator.hs
+++ b/byg/src/DependencyGenerator.hs
@@ -27,11 +27,12 @@ module DependencyGenerator
   , fileComponents
   , lowerString
   , elemOf
+  , makeTemplate
   , applyTemplate
   , toText
   , listDirectory
   , isDirectory
-  , readTemplate
+  , readTextFile
   , convertImage
   , saveFile
   , copyFile
@@ -213,6 +214,12 @@ elemOf a b = do
   b' <- toToken b
   runFunction ElemOf $ TupleToken (a', b')
 
+makeTemplate :: (TokenableTo Text a, TokenableTo Text b) => a -> b -> DepGenM' Template
+makeTemplate a b = do
+  a' <- toToken a
+  b' <- toToken b
+  runFunction MakeTemplate $ TupleToken (a', b')
+
 applyTemplate :: (TokenableTo Template a, TokenableTo Text b) => a -> b -> DepGenM' Text
 applyTemplate a b = do
   a' <- toToken a
@@ -228,11 +235,8 @@ listDirectory a = runFunctionIO ListDirectory =<< toToken a
 isDirectory :: TokenableTo FilePath a => a -> DepGenM' Bool
 isDirectory a = runFunctionIO IsDirectory =<< toToken a
 
-readTemplate :: (TokenableTo FilePath a, TokenableTo Text b) => a -> b -> DepGenM' Template
-readTemplate a b = do
-  a' <- toToken a
-  b' <- toToken b
-  runFunctionIO ReadTemplate $ TupleToken (a', b')
+readTextFile :: TokenableTo FilePath a => a -> DepGenM' Text
+readTextFile a = runFunctionIO ReadTextFile =<< toToken a
 
 convertImage :: (TokenableTo (FilePath, FilePath) a, TokenableTo ImageConversionSettings b) => a -> b -> DepGenM ()
 convertImage a b = do
diff --git a/byg/src/Evaluation/Function.hs b/byg/src/Evaluation/Function.hs
index aa96038..cc9d0b7 100644
--- a/byg/src/Evaluation/Function.hs
+++ b/byg/src/Evaluation/Function.hs
@@ -52,6 +52,11 @@ evalFunction f x = case (f, x) of
   (ElemOf, Tuple (y, List ys)) ->
     Bool (y `elem` ys)
 
+  (MakeTemplate, Tuple (Text t, Text c)) ->
+    let (beforeContent, after) = T.breakOn c t
+        afterContent = T.drop (T.length c) after
+    in Template $ TemplateParts beforeContent afterContent
+
   (ApplyTemplate, Tuple (Template (TemplateParts beforeContent afterContent), Text t)) ->
     Text $ T.concat [beforeContent, t, afterContent]
 
diff --git a/byg/src/Evaluation/FunctionIO.hs b/byg/src/Evaluation/FunctionIO.hs
index b56a9ce..4a87c49 100644
--- a/byg/src/Evaluation/FunctionIO.hs
+++ b/byg/src/Evaluation/FunctionIO.hs
@@ -7,7 +7,6 @@ import Prelude hiding (String, FilePath)
 import Types.Values
 import Types (FunctionIO(..), Value(..), toValue)
 
-import qualified Data.Text as T
 import qualified Data.Text.Lazy as TL
 import qualified Data.Text.IO as T
 import qualified Text.Pandoc as P
@@ -24,11 +23,8 @@ evalFunctionIO f x = case (f, x) of
   (IsDirectory, String (StringWrapper s)) ->
     Bool <$> doesDirectoryExist s
 
-  (ReadTemplate, Tuple (String (StringWrapper s), Text c)) -> do
-    t <- T.readFile s
-    let (beforeContent, after) = T.breakOn c t
-        afterContent = T.drop (T.length c) after
-    pure $ Template $ TemplateParts beforeContent afterContent
+  (ReadTextFile, String (StringWrapper s)) ->
+    Text <$> T.readFile s
 
   (ConvertImage, Tuple (Tuple (String (StringWrapper source), String (StringWrapper target)),
                         ImageConversionSettings (ResizeToWidth widthResized))) -> do
diff --git a/byg/src/SiteGenerator.hs b/byg/src/SiteGenerator.hs
index 258b828..02ca838 100644
--- a/byg/src/SiteGenerator.hs
+++ b/byg/src/SiteGenerator.hs
@@ -62,7 +62,7 @@ generateSite = do
   recipesDir <- inject "retter"
   outputRecipesDir <- joinPaths outputDir recipesDir
   makeDir outputRecipesDir
-  template <- readTemplate (inject "template.html") (inject "CONTENT")
+  template <- makeTemplate (readTextFile (inject "template.html")) (inject "CONTENT")
   indexName <- inject "index.html"
   dirNames <- listDirectory recipesDir
   dirPaths <- mapDepGenM (joinPaths recipesDir) dirNames
diff --git a/byg/src/Types/Function.hs b/byg/src/Types/Function.hs
index f9ff42c..e863293 100644
--- a/byg/src/Types/Function.hs
+++ b/byg/src/Types/Function.hs
@@ -12,6 +12,7 @@ data Function = AppendStrings
               | FileComponents
               | LowerString
               | ElemOf
+              | MakeTemplate
               | ApplyTemplate
               | ToText
   deriving (Show, Lift)
diff --git a/byg/src/Types/FunctionIO.hs b/byg/src/Types/FunctionIO.hs
index 87e6dbb..4a1f25b 100644
--- a/byg/src/Types/FunctionIO.hs
+++ b/byg/src/Types/FunctionIO.hs
@@ -6,7 +6,7 @@ import Language.Haskell.TH.Syntax (Lift)
 
 data FunctionIO = ListDirectory
                 | IsDirectory
-                | ReadTemplate
+                | ReadTextFile
                 | ConvertImage
                 | SaveFile
                 | CopyFile