refactor(Compiler): eliminate Maybe Text indirection in CompilationStrategy

- csWriter now writes files directly (WriterOptions -> Pandoc -> FilePath -> IO (Either DocsterError ()))
- csPostProcess no longer takes text content (String -> IO (Either DocsterError ()))
- Each strategy owns its complete output logic (PDF/HTML/DOCX)
- Remove generateOutputFile (eliminated unused CompilationStrategy parameter)
- Pipeline: generateOutputM >>= processOutput => writeAndProcessOutput (1 step)
- Pandoc 3.7 compatibility: writeDocx returns ByteString instead of ()

.gitignore: exclude stack/cabal config and generated files

.gitignore

@@ -1,6 +1,8 @@
 dist-newstyle
 dist-newstyle
 /.stack-work/
+/.stack-root/
+/.cabal-config/
 *.mmd
 *.png
 *.svg
@@ -10,3 +12,10 @@ dist-newstyle
 dist-newstyle
 output/
 *.log
+cabal.project
+lts-24-34.yaml
+stack-setup-2.yaml
+analytics-charts.md
+architecture-deep-dive.md
+devcontainer.org
+root.json

src/Docster/Compiler.hs

@@ -47,7 +47,6 @@ data CompilationContext = CompilationContext
   , ccDocName :: Text
   , ccReaderOptions :: ReaderOptions
   , ccConfig :: DiagramConfig
-  , ccWritesFile :: Bool
   }
 
 -- | Monad stack for compilation pipeline
@@ -57,44 +56,57 @@ type CompilationM = ReaderT CompilationContext (ExceptT DocsterError IO)
 data CompilationStrategy = CompilationStrategy
   { -- | Format for diagram configuration
     csOutputFormat :: OutputFormat
-    -- | Pandoc writer function (returns Text for HTML/PDF, unused for DOCX)
+    -- | Pandoc writer: writes output directly to the given file path
-  , csWriter :: WriterOptions -> Pandoc -> PandocIO Text
+  , csWriter :: WriterOptions -> Pandoc -> FilePath -> IO (Either DocsterError ())
-    -- | Post-processing function for the generated content
+    -- | Post-processing after write (PDF→xelatex, HTML→open browser, DOCX→noop)
-  , csProcessOutput :: String -> Text -> IO (Either DocsterError ())
+  , csPostProcess :: String -> IO (Either DocsterError ())
     -- | Success message formatter
   , csSuccessMessage :: String -> Text
-    -- | True for formats where writer writes a file directly (DOCX)
-  , csWritesFile :: Bool
   }
 
 -- | PDF compilation strategy
 pdfStrategy :: CompilationStrategy
 pdfStrategy = CompilationStrategy
   { csOutputFormat = PDF
-  , csWriter = writeLaTeX
+  , csWriter = \opts doc path -> do
-  , csProcessOutput = processPDFOutput
+      result <- runIO (writeLaTeX opts doc)
+      case result of
+        Left err -> return $ Left $ FileError $ "LaTeX write failed: " <> T.pack (show err)
+        Right latex -> do
+          TIO.writeFile path (latexTemplate latex)
+          return $ Right ()
+  , csPostProcess = processPDFOutput
   , csSuccessMessage = \path -> successEmoji <> " PDF written to " <> T.pack path
-  , csWritesFile = False
   }
 
 -- | HTML compilation strategy  
 htmlStrategy :: CompilationStrategy
 htmlStrategy = CompilationStrategy
   { csOutputFormat = HTML
-  , csWriter = writeHtml5String
+  , csWriter = \opts doc path -> do
-  , csProcessOutput = processHTMLOutput
+      result <- runIO (writeHtml5String opts doc)
+      case result of
+        Left err -> return $ Left $ FileError $ "HTML write failed: " <> T.pack (show err)
+        Right html -> do
+          TIO.writeFile path html
+          return $ Right ()
+  , csPostProcess = processHTMLOutput
   , csSuccessMessage = \path -> successEmoji <> " HTML written to " <> T.pack path
-  , csWritesFile = False
   }
 
 -- | DOCX compilation strategy (Pandoc writes file directly)
 docxStrategy :: CompilationStrategy
 docxStrategy = CompilationStrategy
   { csOutputFormat = DOCX
-  , csWriter = \_ _ -> return ""  -- unused: writeDocx writes file directly
+  , csWriter = \opts doc path -> do
-  , csProcessOutput = \_ _ -> return $ Right ()  -- no post-processing needed
+      result <- runIO (writeDocx opts doc)
+      case result of
+        Left err -> return $ Left $ FileError $ "DOCX generation failed: " <> T.pack (show err)
+        Right docxBS -> do
+          BSL.writeFile path docxBS
+          return $ Right ()
+  , csPostProcess = \_ -> return $ Right ()  -- no post-processing needed
   , csSuccessMessage = \path -> successEmoji <> " DOCX written to " <> T.pack path
-  , csWritesFile = True
   }
 
 -- | Parse LaTeX log content to extract meaningful error messages
@@ -160,11 +172,10 @@ extractFatalErrors = mapMaybe extractFatal
       | "! " `T.isPrefixOf` line && not ("Missing character:" `T.isInfixOf` line) = Just $ T.drop 2 line
       | otherwise = Nothing
 
--- | Process PDF output: LaTeX template application and direct XeLaTeX compilation
+-- | Process PDF output: direct XeLaTeX compilation (LaTeX already written by csWriter)
-processPDFOutput :: String -> Text -> IO (Either DocsterError ())
+processPDFOutput :: String -> IO (Either DocsterError ())
-processPDFOutput outputPath latexOutput = do
+processPDFOutput outputPath = do
-  let completeLatex = latexTemplate latexOutput
+  let logOutputPath = replaceExtension outputPath "log"
-      logOutputPath = replaceExtension outputPath "log"
   
   -- Use temporary directory for LaTeX compilation
   withSystemTempDirectory "docster-latex" $ \tempDir -> do
@@ -172,9 +183,6 @@ processPDFOutput outputPath latexOutput = do
         pdfFile = tempDir </> "document.pdf"
         logFile = tempDir </> "document.log"
     
-    -- Write LaTeX content to temporary file
-    TIO.writeFile texFile completeLatex
-    
     -- Run XeLaTeX compilation
     (exitCode, _stdout, stderr) <- readProcessWithExitCode "xelatex" 
       [ "-output-directory=" <> tempDir
@@ -210,11 +218,9 @@ processPDFOutput outputPath latexOutput = do
           errorSummary <> "\n\n" <>
           "Full LaTeX log written to: " <> T.pack logOutputPath
 
--- | Process HTML output: file writing and browser opening
+-- | Process HTML output: open browser (HTML already written by csWriter)
-processHTMLOutput :: String -> Text -> IO (Either DocsterError ())
+processHTMLOutput :: String -> IO (Either DocsterError ())
-processHTMLOutput outputPath html = do
+processHTMLOutput outputPath = do
-  TIO.writeFile outputPath html
-  
   -- Open the generated HTML file in browser for verification
   putStrLn $ "🌐 Opening " <> outputPath <> " in browser for error checking..."
   void $ callProcess "open" [outputPath]
@@ -267,28 +273,13 @@ transformDocumentM pandoc = do
   docName <- asks ccDocName
   liftEitherM $ transformDocument config docName pandoc
 
--- | Pipeline step: Generate output using format-specific writer
+-- | Pipeline step: Write output and post-process (format-specific)
-generateOutputM :: Pandoc -> CompilationM Text
+writeAndProcessOutput :: Pandoc -> CompilationM ()
-generateOutputM pandoc = do
+writeAndProcessOutput pandoc = do
   strategy <- asks ccStrategy
-  writesFile <- asks ccWritesFile
+  outputPath <- asks ccOutputPath
-  if writesFile
+  liftEitherM $ csWriter strategy def pandoc outputPath
-    then do
+  liftEitherM $ (csPostProcess strategy) outputPath
-      outputPath <- asks ccOutputPath
-      _ <- liftIO $ generateOutputFile strategy outputPath pandoc
-      return ""  -- placeholder, won't be used
-    else liftEitherM $ generateOutput strategy pandoc
-
--- | Pipeline step: Process output and write to file
-processOutput :: Text -> CompilationM ()
-processOutput output = do
-  strategy <- asks ccStrategy
-  writesFile <- asks ccWritesFile
-  if writesFile
-    then return ()  -- file already written by writer
-    else do
-      outputPath <- asks ccOutputPath
-      liftEitherM $ csProcessOutput strategy outputPath output
 
 -- | Pipeline step: Print success message
 printSuccess :: CompilationM ()
@@ -302,8 +293,8 @@ compileWithStrategy :: CompilationStrategy -> SourceDir -> OutputDir -> Text ->
 compileWithStrategy strategy sourceDir outputDir docName (OutputPath inputPath) (OutputPath outputPath) = do
   let readerOptions = def { readerExtensions = getDefaultExtensions "markdown" }
       config = DiagramConfig sourceDir outputDir (csOutputFormat strategy)
-      context = CompilationContext strategy inputPath outputPath docName readerOptions config (csWritesFile strategy)
+      context = CompilationContext strategy inputPath outputPath docName readerOptions config
-      pipeline = readContent >>= parseDocument >>= transformDocumentM >>= generateOutputM >>= processOutput >> printSuccess
+      pipeline = readContent >>= parseDocument >>= transformDocumentM >>= writeAndProcessOutput >> printSuccess
 
   runExceptT $ runReaderT pipeline context
 
@@ -315,26 +306,7 @@ parseMarkdown readerOptions content = do
     Left err -> Left $ FileError $ "Failed to parse markdown: " <> T.pack (show err)
     Right pandoc -> Right pandoc
 
--- | Generate output using the strategy's writer with error handling
-generateOutput :: CompilationStrategy -> Pandoc -> IO (Either DocsterError Text)
-generateOutput strategy transformed = do
-  result <- runIO $ csWriter strategy def transformed
-  return $ case result of
-    Left err -> Left $ case csOutputFormat strategy of
-      PDF -> PDFGenerationError $ "LaTeX generation failed: " <> T.pack (show err)
-      HTML -> FileError $ "HTML generation failed: " <> T.pack (show err)
-      DOCX -> FileError $ "DOCX generation failed: " <> T.pack (show err)
-    Right output -> Right output
 
--- | Generate output file directly (for DOCX which writes to file)
-generateOutputFile :: CompilationStrategy -> FilePath -> Pandoc -> IO (Either DocsterError ())
-generateOutputFile _ outputPath pandoc = do
-  result <- runIO $ writeDocx def pandoc
-  case result of
-    Left err -> return $ Left $ FileError $ "DOCX generation failed: " <> T.pack (show err)
-    Right docxBS -> do
-      BSL.writeFile outputPath docxBS
-      return $ Right ()
 
 -- | Compile markdown to PDF using XeLaTeX
 compileToPDF :: FilePath -> IO ()