Define Cooklang data model and add DerivingStrategies + containers deps

- Add full Cooklang (.cook) recipe data model to Roux.Types:
  Recipe, Section, Step, StepItem (with StepText/StepIngredient/
  StepCookware/StepTimer/StepRecipeRef/StepNote/StepComment/StepBreak),
  Ingredient, Cookware, Timer, RecipeRef, Quantity, Duration, Metadata
- Enable DerivingStrategies extension project-wide
- Add containers to build dependencies

package.yaml

@@ -9,6 +9,7 @@ copyright:   2026 James Brechtel
 license:     BSD-3-Clause
 
 default-extensions:
+  - DerivingStrategies
   - OverloadedStrings
 
 ghc-options:
@@ -28,6 +29,7 @@ dependencies:
   - blaze-html
   - blaze-markup
   - bytestring
+  - containers
   - directory
   - http-types
   - optparse-applicative

roux-server.cabal

@@ -25,6 +25,7 @@ library
   hs-source-dirs:
       src
   default-extensions:
+      DerivingStrategies
       OverloadedStrings
   ghc-options: -Wall -Werror -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints
   build-depends:
@@ -32,6 +33,7 @@ library
     , blaze-html
     , blaze-markup
     , bytestring
+    , containers
     , directory
     , http-types
     , optparse-applicative
@@ -51,6 +53,7 @@ executable roux-server
   hs-source-dirs:
       app
   default-extensions:
+      DerivingStrategies
       OverloadedStrings
   ghc-options: -Wall -Werror -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints -threaded -rtsopts -with-rtsopts=-N
   build-depends:
@@ -58,6 +61,7 @@ executable roux-server
     , blaze-html
     , blaze-markup
     , bytestring
+    , containers
     , directory
     , http-types
     , optparse-applicative
@@ -80,6 +84,7 @@ test-suite roux-server-test
   hs-source-dirs:
       test
   default-extensions:
+      DerivingStrategies
       OverloadedStrings
   ghc-options: -Wall -Werror -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints
   build-depends:
@@ -87,6 +92,7 @@ test-suite roux-server-test
     , blaze-html
     , blaze-markup
     , bytestring
+    , containers
     , directory
     , http-types
     , optparse-applicative

src/Roux/Types.hs

@@ -1,9 +1,185 @@
-{- | Core types for Roux.
+{- | Core types for Roux.  Models the structure of a parsed Cooklang (.cook)
+recipe file as specified at <https://cooklang.org/docs/spec/>.
+
+Hierarchy:
+
+@
+Recipe
+  Metadata                  — YAML front matter (title, tags, servings, …)
+  NonEmpty Section           — at least one section per recipe
+
+Section
+  Maybe Text                 — optional section name ("Dough", "Filling")
+  NonEmpty Step              — at least one step per section
+
+Step
+  [StepItem]                 — sequence of inline elements
+
+StepItem
+  StepText                   — plain text
+  StepIngredient             — \@name{amount%unit}(preparation)
+  StepCookware               — \#name{}
+  StepTimer                  — \~name{duration%unit}
+  StepRecipeRef              — \@.\/path\/to\/recipe{amount}
+  StepNote                   — \> note / commentary
+  StepComment                — [- comment -]
+  StepBreak                  — \\ at end of line
+@
 -}
 module Roux.Types
-    ( -- * Types
+    ( -- * Recipe
-      RecipeDir (..)
+      Recipe (..)
+
+      -- * Sections and steps
+    , Section (..)
+    , Step (..)
+
+      -- * Inline elements
+    , StepItem (..)
+    , Ingredient (..)
+    , Cookware (..)
+    , Timer (..)
+    , RecipeRef (..)
+
+      -- * Quantities and durations
+    , Quantity (..)
+    , Duration (..)
+
+      -- * Metadata
+    , Metadata (..)
     ) where
 
--- | Path to the directory containing Cooklang recipe files.
+import Data.List.NonEmpty (NonEmpty)
-newtype RecipeDir = RecipeDir FilePath
+import Data.Map.Strict (Map)
+import Data.Text (Text)
+
+-- ---------------------------------------------------------------------------
+-- Top-level
+-- ---------------------------------------------------------------------------
+
+-- | A fully parsed Cooklang recipe file.
+data Recipe = Recipe
+    { recipeMetadata :: !Metadata
+    , recipeSections :: !(NonEmpty Section)
+    }
+    deriving stock (Eq, Show)
+
+-- ---------------------------------------------------------------------------
+-- Sections and steps
+-- ---------------------------------------------------------------------------
+
+-- | A named or unnamed section within a recipe.  Each section contains one
+-- or more cooking steps.
+data Section = Section
+    { sectionName  :: !(Maybe Text)
+    , sectionSteps :: !(NonEmpty Step)
+    }
+    deriving stock (Eq, Show)
+
+-- | A single cooking step — one paragraph of text in the Cooklang file,
+-- separated from other steps by a blank line.
+newtype Step = Step
+    { unStep :: [StepItem]
+    }
+    deriving stock (Eq, Show)
+
+-- ---------------------------------------------------------------------------
+-- Inline elements
+-- ---------------------------------------------------------------------------
+
+-- | An element that appears within a step.
+data StepItem
+    = StepText !Text
+    | StepIngredient !Ingredient
+    | StepCookware !Cookware
+    | StepTimer !Timer
+    | StepRecipeRef !RecipeRef
+    | StepNote !Text
+    | StepComment !Text
+    | StepBreak
+    deriving stock (Eq, Show)
+
+-- | An ingredient reference.
+--
+-- @\@salt\@ground black pepper{}\@potato{2}\@bacon strips{1%kg}@
+data Ingredient = Ingredient
+    { ingName        :: !Text
+    , ingQuantity    :: !(Maybe Quantity)
+    , ingPreparation :: !(Maybe Text)
+    }
+    deriving stock (Eq, Show)
+
+-- | A piece of cookware.
+--
+-- @\#pot\#potato masher{}@
+newtype Cookware = Cookware
+    { cwName :: Text
+    }
+    deriving stock (Eq, Show)
+
+-- | A timer.
+--
+-- @\{25%minutes\}\~eggs{3%minutes}@
+data Timer = Timer
+    { timerName     :: !(Maybe Text)
+    , timerDuration :: !Duration
+    }
+    deriving stock (Eq, Show)
+
+-- | A reference to another recipe, signalled by a path starting with @.\/@.
+--
+-- @\@.\/sauces\/Hollandaise{150%g}@
+data RecipeRef = RecipeRef
+    { refPath     :: !FilePath
+    , refQuantity :: !(Maybe Quantity)
+    }
+    deriving stock (Eq, Show)
+
+-- ---------------------------------------------------------------------------
+-- Quantities and durations
+-- ---------------------------------------------------------------------------
+
+-- | An ingredient quantity with optional unit and scaling lock.
+--
+-- @{2}\{1%kg}\{1\/2%tbsp}\{=1%tsp}@
+data Quantity = Quantity
+    { quantityAmount :: !Rational   -- ^ e.g. @1\/2@, @3@, @3\/4@
+    , quantityUnit   :: !(Maybe Text)  -- ^ e.g. @\"kg\"@, @\"tbsp\"@
+    , quantityFixed  :: !Bool         -- ^ @{=1%tsp}@ — locked from scaling
+    }
+    deriving stock (Eq, Show)
+
+-- | A timer duration — structurally similar to 'Quantity' but semantically
+-- distinct.  Timers are not scaled with serving size.
+data Duration = Duration
+    { durationAmount :: !Rational   -- ^ e.g. @25@, @3@
+    , durationUnit   :: !(Maybe Text)  -- ^ e.g. @\"minutes\"@, @\"hours\"@
+    }
+    deriving stock (Eq, Show)
+
+-- ---------------------------------------------------------------------------
+-- Metadata
+-- ---------------------------------------------------------------------------
+
+-- | Metadata parsed from YAML front matter (the @---@ … @---@ block at the
+-- top of a @.cook@ file).
+--
+-- Canonical metadata keys are lifted to dedicated fields; everything else
+-- lives in 'metaCustom'.
+data Metadata = Metadata
+    { metaTitle       :: !(Maybe Text)
+    , metaServings    :: !(Maybe (Int, Maybe Text))
+    , metaAuthor      :: !(Maybe Text)
+    , metaSource      :: !(Maybe Text)
+    , metaTotalTime   :: !(Maybe Duration)
+    , metaPrepTime    :: !(Maybe Duration)
+    , metaCookTime    :: !(Maybe Duration)
+    , metaDifficulty  :: !(Maybe Text)
+    , metaCuisine     :: !(Maybe Text)
+    , metaDiet        :: ![Text]
+    , metaTags        :: ![Text]
+    , metaImage       :: !(Maybe Text)
+    , metaDescription :: !(Maybe Text)
+    , metaCustom      :: !(Map Text Text)
+    }
+    deriving stock (Eq, Show)