module basic where

open import Agda.Primitive renaming (Set to Type)
open import Agda.Builtin.Float
open import Agda.Builtin.String
open import Agda.Builtin.IO
open import Agda.Builtin.Unit

postulate
  HTTPModule : Type
  http : HTTPModule
  HTTPServer : Type
  HTTPReq : Type
  HTTPRes : Type
  modify : Type → Type
  modLog : {A : Type} → modify A
  setStatusCode : Float → modify HTTPRes
  setHeader : String → String → modify HTTPRes
  setEnd : String → modify HTTPRes
  pure : {A : Type} → A → modify A
  _>>=_ : {A : Type} → modify A → (A → modify A) → modify A
  _>>_ : {A : Type} → modify A → modify A → modify A
  createServer : HTTPModule → (HTTPReq → modify HTTPRes) → HTTPServer
  serverListen : HTTPServer → Float → String → IO ⊤ → IO ⊤
  doNothing : IO ⊤
  putStrLn : String → IO ⊤

{-# COMPILE JS putStrLn = (str) => { console.log(str); } #-}
  
{-# COMPILE JS http = require('http') #-}

{-# COMPILE JS setStatusCode = ((float) => { return (res) => { res.statusCode = float; }}) #-}
{-# COMPILE JS setHeader = ((header) => { return (content) => { return (res) => { res.setHeader(header, content); }}}) #-}
{-# COMPILE JS setEnd = ((content) => { return (res) => { res.end(content); }}) #-}

{-# COMPILE JS modLog = ((a) => { return (res) => { console.log(res); }}) #-}
{-# COMPILE JS pure = ((a) => { return (res) => { return structuredClone(a); }}) #-}
{-# COMPILE JS _>>=_ = ((a) => { return (ma) => { return (amb) => { return (res) => { amb(ma(res)); }}}}) #-}
{-# COMPILE JS _>>_ = ((a) => { return (ma) => { return (mb) => { return (res) => { ma(res); mb(res); }}}}) #-}

{-# COMPILE JS createServer = ((http) => { return (handler) => { return http.createServer((req, res) => { handler(req)(res); }); }}) #-}
{-# COMPILE JS serverListen = ((serv) => { return (port) => { return (host) => { return (action) => { return () => { serv.listen(port, host, action) }}}}}) #-}

{-# COMPILE JS doNothing = (() => {}) #-}

port : Float
port = 3000.0

hostname : String
hostname = "localhost"

handleReg : modify HTTPRes
handleReg = do
  setStatusCode 200.0
  setHeader "Content-Type" "text/plain"
  setEnd "Hello World"

server : HTTPServer
server = createServer http (λ _ → handleReg)

main : IO ⊤
main = serverListen server port hostname (putStrLn "served request")