import ../../base
import std/[re,httpclient,json,strutils,tables]


# TODO:
#       Query available languages, maybe have selection panel
#       Maybe store last used so future translations are more fluent

const LIBRETRANSLATE_URL = "https://libretranslate.pussthecat.org/"
const HOME = "en"
let   LANG_RE = re"\w+>\w+"
let   DETECT_RE = re"\bd(etect)?\b"
var   current = @["de",HOME]
var   detected = {"detected":"0","confidence":"0","language":"en"}.toTable

type
  Request = object
    source: string
    target: string
    q: string
    format: string

proc main(messages: varargs[string] = @[])

proc newRequest(): Request =
  return Request(source:current[0],
                 target:current[1],
                 q: "",
                 format: "text",)

proc parseReq(req: string): Request =
  var langs = findAll(req,LANG_RE)
  var r = newRequest()
  let query = replace(req,LANG_RE,"")
  r.q = query
  if len(langs) > 0:
    let lang = langs[0]
    langs = lang.split(re">")
    current[0] = langs[0].toLowerAscii()
    current[1] = langs[1].toLowerAscii()
  r.source = current[0].toLowerAscii()
  r.target = current[1].toLowerAscii()
  if query == "":
    main()
  return r

proc answerTranslate(response: string, req: Request) =
  let r = parseJson(response)
  try:
    let ans = r["translatedText"].getStr()
    main(ans)
  except:
    main("Error : " & r["error"].getStr())

proc goTranslate(req: string) =
  let r = parseReq(req)
  if r.q != "":
    var client = newHTTPClient()
    client.headers = newHttpHeaders({"Content-Type":"application/json"})
    let body = %*r
    let response = client.request(LIBRETRANSLATE_URL & "translate", httpMethod = HttpPost, body = $body)
    if response.status != "":
      answerTranslate(response.body, r)

proc flipCurrent() =
  current = @[current[1],current[0]]
  main()

proc detectLanguage(str: string) =
  let term = replace(str,DETECT_RE,"")
  echo "detecting ", term
  if term != "":
    var client = newHTTPClient()
    client.headers = newHttpHeaders({"Content-Type":"application/json"})
    let body = %*Request(q:term)
    let response = client.request(LIBRETRANSLATE_URL & "detect", httpMethod = HttpPost, body = $body)
    if response.status != "":
      let r = parseJson(response.body)
      echo r
      try:
        detected["confidence"] = $r[0]["confidence"].getFloat()
        detected["language"] = r[0]["language"].getStr()
        detected["detected"] = "1"
        current[0] = detected["language"]
        current[1] = HOME
        goTranslate(term)
      except:
        try:
          main("Error : " & r["error"].getStr())
        except:
          main("Error Parsing Json")
  return

proc main(messages:varargs[string] = @[]) =
  var info = newInfo("Translate")
  info.selected_bg = green
  var args: seq[string] = @[]
  for msg in messages:
    if msg != "":
      args.add(msg)
  args.add(current[0] & " > " & current[1])
  if detected["detected"] == "1":
    args.add("detected language : " & detected["language"])
    args.add("detected confidence : " & detected["confidence"])
    detected["detected"] = "0"
  if len(messages) > 0:
    args.add("back")
  args.add("exit")
  let output = outputData(info,args)
  if output == "exit" or output == "":
    return
  elif output == "back":
    main()
  elif output == current[0] & " > " & current[1]:
    flipCurrent()
  elif re.startsWith(output,DETECT_RE):
    detectLanguage(output)
  elif output in messages:
    copyToClipboard(output)
  else:
    goTranslate(output)
  return

if isMainModule:
  main()