initial (functional?) version

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+TAGS
+*~
+test/*
+testout/*
+testbak/*
+dist-newstyle
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
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+# Revision history for loom
+
+## 0.1.0.0 -- YYYY-mm-dd
+
+* First version. Released on an unsuspecting world.
diff --git a/LICENSE b/LICENSE
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+Copyright (c) 2026 Thomas Ulmer
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/README.md b/README.md
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+# Loom - Minimal site "generator"
+Loom is a single file haskell program that generates a static html site from a given set of framgents. It is heavily inspired by (node)[https://git.sr.ht/~tagglink/node]. 
+
+## Building Loom
+Loom requires a Haskell2010 compiler and the following packages:
+- text
+- filepath
+- directory
+
+GHC should work if it's decently recent. MHS likely is also workable but untested.
+
+## Using Loom
+Simply make a directory of html fragments such as:
+```
+testbak/
+├── a.html
+├── b
+│   ├── c.frag
+│   ├── d
+│   │   ├── e.html
+│   │   └── index.html
+│   └── index.html
+└── index.html
+```
+where `.frag` and `.html` are equivalent, and invoke loom:
+```
+loom -r {root path} -o {output path} [-s {static path}]
+```
+
+Each fragment will generate a html page in the output directory in the same structure. The generated page will be composed of a header and footer with the text of the fragment placed in `<main>`. The header also conatins the title of the page, which can be specified by placing a line
+```
+<!-- == title={title} -->
+```
+on the first line of the fragment file. The title cannot contain newlines or the vertical bar character. If unspecified it will default to the basename of the fragment file.
+
+The header will also include a `<nav>` which produces a tree featuring the spine from the current page to the root, all descendants of the current page, and any sibling or sibling of an ancestor of the current page. The tree is sorted by file name, should you wish for the tree order and page title to differ.
+
+A static path, if specified, is simply recursively copied into the output directory after generation occurs.
+
+## Limitations compared to node
+- No markdown conversion
+- No in-page table of contents generation
+- Requires a functional Haskell ecosystem
+
diff --git a/loom.cabal b/loom.cabal
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+cabal-version:      3.0
+name:               loom
+version:            0.1.0.0
+-- synopsis:
+-- description:
+homepage:           tccq.net
+license:            MIT
+license-file:       LICENSE
+author:             Thomas Ulmer
+maintainer:         thomasmulmer02@gmail.com
+-- copyright:
+category:           Web
+build-type:         Simple
+extra-doc-files:    CHANGELOG.md
+-- extra-source-files:
+
+common warnings
+    ghc-options: -Wall
+
+executable loom
+    import:           warnings
+    main-is:          Main.hs
+    -- other-modules:
+    -- other-extensions:
+    build-depends:    base ^>=4.18.3.0
+                    , filepath
+                    , directory
+                    , text
+    hs-source-dirs:   src
+    default-language: Haskell2010
diff --git a/src/Main.hs b/src/Main.hs
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+module Main where
+
+import System.Directory
+import System.FilePath
+import System.Environment (getArgs)
+import System.IO
+import Data.Maybe (fromMaybe, isJust, fromJust)
+import Data.List (isPrefixOf, isSuffixOf, scanl, scanr, zipWith3, intersperse, sort, inits, tails)
+import Control.Monad (when, unless)
+import System.Exit (die)
+
+import qualified Data.Text as T
+import qualified Data.Text.IO as T
+
+isFragment :: FilePath -> Bool
+isFragment f =
+  (isSuffixOf ".html" f || isSuffixOf ".frag" f)
+
+valid :: FilePath -> FilePath -> Bool
+valid r f =
+  and $ (isAbsolute r):(isAbsolute f):zipWith (==) r f
+
+prettyName :: FilePath -> String
+{- XXX more -}
+prettyName f = takeBaseName $ dropExtension f
+
+header :: T.Text -> T.Text -> T.Text
+header title nav = T.unlines
+  [ T.pack "<!DOCTYPE html>"
+  , T.pack "<html>"
+  , T.pack "  <head>"
+  , T.pack "    <meta charset='UTF-8' />"
+  , T.concat [T.pack "    <title>" , title , T.pack "</title>" ]
+  , T.pack "    <link rel=\"stylesheet\" href=\"/css/style.css\" />"
+  , T.pack "    <link rel=\"icon\" href=\"/favicon.ico\" type=\"image/x-icon\"/>"
+  , T.pack "  </head>"
+  , T.pack "  <body>"
+  , T.pack "  <div class=\"stuck\">"
+  , T.pack "    <header>"
+  , T.pack "      <p>"
+  , T.pack "        Professional Webring >>"
+  , T.pack "        <a href=\"https://roscoeeh.github.io\">Prev - Roscoe</a>"
+  , T.pack "        |"
+  , T.pack "        <a href=\"https://elle-wen.github.io\">Next - Elle</a>"
+  , T.pack "      </p>"
+  , T.pack "    </header>"
+  , T.concat [ T.pack "<nav>" , nav , T.pack "</nav>" ]
+  , T.pack "  </div>"
+  , T.pack "    <main>"
+  ]
+
+footer :: T.Text
+footer = T.pack $ unlines
+  [ "</main>"
+  , "<footer>"
+  , "</footer>"
+  , "</body>"
+  , "</html>"
+  ]
+
+parse :: FilePath -> IO (T.Text, T.Text)
+{- XXX use T.hGetLine to try to delay the memory cost.
+
+Maybe doesn't matter if I'm going to have it all in memory later
+anyway?
+-}
+parse f = withFile f ReadMode $ \h -> do
+  c <- T.hGetContents h
+  case T.lines c of
+    [] -> pure (fallback, c)
+    l:_ -> case T.stripPrefix (T.pack "<!-- == ") l
+                >>= T.stripSuffix (T.pack " -->") of
+      Nothing -> pure (fallback, c)
+      Just comment ->
+        let pairs = T.splitOn (T.pack "|") comment
+            kvs = map (dropEq . T.span (/= '=')) pairs
+            name = fromMaybe fallback $ lookup (T.pack "title") kvs
+        in pure (name, c)
+  where fallback = T.pack $ prettyName f
+        dropEq (key, ev) = case T.uncons ev of
+          Just ('=', rest) -> (key,rest)
+          _ -> (key, ev)
+
+data Nav
+  = NavDir { navChildren :: [Nav]
+           , navIndexFrag :: Nav {- will be NavFile, contains title -}
+           , navDirPath :: FilePath
+           }
+  | NavFile { navFrag :: T.Text
+            , navTitle :: T.Text
+            , navFilePath :: FilePath
+            }
+
+instance Show Nav where
+  show (NavDir cs _ p) =
+    concat $ intersperse "\n"
+      [ "NavDir " ++ p ++ ":"
+      , concat $ intersperse "\n" $ map (indent . show) cs
+      ]
+    where indent s = concat $ intersperse "\n" $ map ("\t"++) $ lines s
+  show (NavFile _ t p) =
+    "NavFile " ++ T.unpack t ++ " " ++ p
+
+convert :: FilePath -> FilePath -> IO Nav
+convert r f = do
+  unless (valid r f) $
+    error $ "Don't know what to do with: " ++ f
+  de <- doesDirectoryExist f
+  fe <- (isFragment f &&) <$> doesFileExist f
+  case de of
+    True -> do
+      allChildren <- (map (f </>)) <$> listDirectory f
+      let downlinks = sort $ filter (\x -> valid r x && not (isSuffixOf "index.html" x)) $ allChildren
+      navChildren <- mapM (convert r) downlinks
+      navIndexFrag <- do
+        let ifp = f </> "index.html"
+        fe <- doesFileExist ifp
+        case fe of
+          True -> do
+            (name, contents) <- parse ifp
+            pure $ NavFile contents name (makeRelative r ifp)
+          False -> pure $ fallbackIndexNav (makeRelative r ifp) navChildren
+      let navDirPath = makeRelative r f
+      pure $ NavDir { navChildren = navChildren
+                    , navIndexFrag = navIndexFrag
+                    , navDirPath = navDirPath
+                    }
+    False -> case fe of
+      True -> do
+        (navTitle, navFrag) <- parse f
+        let navFilePath = makeRelative r f
+        pure $ NavFile { navFrag = navFrag
+                       , navTitle = navTitle
+                       , navFilePath = navFilePath
+                       }
+      False ->
+        error $ "Path doesn't exist or is not a directory or file: " ++ f
+
+fallbackIndexNav :: FilePath -> [Nav] -> Nav
+fallbackIndexNav p ns = NavFile (fallbackIndexFrag p ns) (T.pack . takeFileName $ takeDirectory p) p
+
+fallbackIndexFrag :: FilePath -> [Nav] -> T.Text
+fallbackIndexFrag _ _ = (T.pack "<p>Fallback index.</p>")
+
+generate :: T.Text -> Nav -> T.Text
+{- Generate the full text of a page. -}
+generate nav (NavFile f t _) =
+  T.concat [ header t nav , f , footer ]
+generate nav (NavDir _ (NavFile f t _) _) =
+  T.concat [ header t nav , f , footer ]
+generate _ _ = error "malformed NavDir"
+
+mkNavItem :: Nav -> T.Text
+{- Generate a listing for a file or a listing for a dir and optionally
+ one level of children -}
+mkNavItem (NavFile _ t p) =
+  T.concat [ T.pack "<li><a class='active' href=\""
+           , T.pack $ (pathSeparator:p -<.> "html")
+           , T.pack "\">"
+           , t
+           , T.pack "</a></li>"
+           ]
+mkNavItem (NavDir _ idxf _) = mkNavItem idxf
+
+emit :: FilePath -> T.Text -> Nav -> T.Text -> IO ()
+emit outdir nav1 f@(NavFile _ _ p) nav2 = do
+  let contents = generate (T.append nav1 nav2) f
+  T.writeFile (outdir </> p -<.> "html") contents
+emit outdir nav1 (NavDir cs i dp) nav2 = do
+  let newdir = outdir </> dp
+  exists <- doesDirectoryExist newdir
+  unless exists $ createDirectory newdir
+
+  let sharedBefore = T.append nav1 $ T.pack "<li><ul>"
+  let sharedAfter = T.append (T.pack "</li></ul>") nav2
+  let ncs = map mkNavItem cs
+  let priors = inits ncs
+  let posts = tails ncs
+  let nbefore = map (\x -> T.append sharedBefore (T.concat x)) priors
+  let nafter  = map (\x -> T.append (T.concat x) sharedAfter ) posts
+  let actions = zipWith3 (emit outdir) (tail nbefore) cs (tail nafter)
+  _ <- sequence actions
+  emit outdir (head nbefore) i (head nafter)
+
+main :: IO ()
+main = do
+  flags@(Flags r o s) <- canonicalizeFlags <$> handleArgs
+  unless (valid r r) $
+    die $ "R isn't valid. Maybe not absolute? " ++ r
+  unless (isAbsolute o) $
+    die $ "O not absolute " ++ o
+  hPutStr stderr $ "Using config: " ++ show flags
+  tree <- convert r r
+  hPutStr stderr $ "\nFound tree:\n" ++ show tree
+  let rNav = T.append (mkNavItem tree) (T.pack "<ul>")
+  emit o rNav tree (T.pack "</ul>")
+  when (isJust s) $
+    case isAbsolute $ fromJust s of
+      True -> copyInto (fromJust s) o
+      False -> die $ "S input not absolute " ++ (fromJust s)
+  where canonicalizeFlags (Flags r o s) =
+          Flags (normalise r) (normalise o) (normalise <$> s)
+
+data Flags = Flags
+  { root :: FilePath
+  , output :: FilePath
+  , static :: Maybe FilePath
+  }
+  deriving (Show)
+
+handleArgs :: IO Flags
+handleArgs = do
+  args <- getArgs
+  when (null args) $ die usage
+  let missing = Flags
+        { root   = error "-r root is required"
+        , output = error "-o output is required"
+        , static = Nothing
+        }
+  helper missing args
+  where helper f [] = pure f
+        helper f ("-r":a:rest) = helper (f { root = a }) rest
+        helper f ("-o":a:rest) = helper (f { output = a }) rest
+        helper f ("-s":a:rest) = helper (f { static = Just a }) rest
+        helper _ ("-h":_) = die usage
+        helper _ (x:_) = die $ "Unknown or orphan flag: " ++ x ++ "\n" ++ usage
+
+usage :: String
+usage = unlines
+  [ "Usage:"
+  , "\tloom -r {root path} -o {output path} [-s {static path}]"
+  , "\t-r supplies a root to pull fragments from"
+  , "\t-o supplies the output directory to place html in"
+  , "\t-s (optional) supplies a directory to be copied into the output after generation"
+  , "all paths must be absolute."
+  , "any fragment may be given a name by having the first line be in the following format:"
+  , "\t<!-- == title={title} -->"
+  , "note that the spaces are important. The title may not contain newlines or the vertical bar character."
+  ]
+
+copyInto ::  FilePath -> FilePath -> IO ()
+copyInto src dst = do
+  se <- doesDirectoryExist src
+  unless se $
+    die $ "source does not exist: " ++ src
+  de <- doesDirectoryExist dst
+  unless de $ createDirectory dst
+  when (isPrefixOf src dst) $
+    die $ "Overlapping directories: " ++ src ++ " to " ++ dst
+  content <- listDirectory src
+  flip mapM_ content $ \name -> do
+    let srcPath = src </> name
+    let dstPath = dst </> name
+    isDirectory <- doesDirectoryExist srcPath
+    if isDirectory
+      then copyInto srcPath dstPath
+      else copyFile srcPath dstPath