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------------------------------------------------------------------------
-- The Agda standard library
--
-- Generic printf function.
------------------------------------------------------------------------

{-# OPTIONS --cubical-compatible --safe #-}

module Text.Printf.Generic where

open import Level using (Level; 0ℓ; _⊔_; Lift)
open import Data.List.Base as List using (List; []; _∷_)
open import Data.Char.Base
open import Data.Maybe.Base hiding (map)
open import Data.Nat.Base using ()
open import Data.Product hiding (map)
open import Data.Product.Nary.NonDependent
open import Data.String.Base
open import Data.Sum.Base using (_⊎_; inj₁; inj₂)
open import Data.Unit using ()
open import Function.Nary.NonDependent
open import Function

open import Text.Format.Generic

private
  variable
     : Level
    A B : Set 

------------------------------------------------------------------------
-- Printf argument specifications.
-- Defines the rendering of chunks.

record PrintfSpec {} (spec : FormatSpec) (A : Set ) : Set (Level.suc 0ℓ  ) where

  open FormatSpec spec public

  field
    renderArg :  arg  ArgType arg  A
    renderStr : String  A

module Type (spec : FormatSpec) where

  open Format spec renaming (Error to FormatError)

  record Error (e : FormatError) : Set  where

  private

    Size : FormatError  Format  
    Size (inj₁ err) = 0
    Size (inj₂ fmt) = size fmt

  Printf :  pr  Set   Set (   (Size pr) 0ℓs)
  Printf (inj₁ err) _ = Error err
  Printf (inj₂ fmt) B = Arrows _  fmt  B

  map :  pr  (A  B)  Printf pr A  Printf pr B
  map (inj₁ err) f p = _
  map (inj₂ fmt) f p = mapₙ _ f p

module Render {spec : FormatSpec} (render : PrintfSpec spec A) where

  open PrintfSpec render
  open Type spec

  open Format spec renaming (Error to FormatError)

  assemble :  fmt  Product⊤ _  fmt   List A
  assemble [] vs                    = []
  assemble (Arg a    fmt) (x , vs) = renderArg a x  assemble fmt vs
  assemble (Raw str  fmt) vs       = renderStr str  assemble fmt vs

  private

    printf′ :  pr  Printf pr (List A)
    printf′ (inj₁ err) = _
    printf′ (inj₂ fmt) = curry⊤ₙ _ (assemble fmt)

  printf : (input : String)  Printf (lexer input) (List A)
  printf input = printf′ (lexer input)