{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}

module Main where

import Prelude hiding(putStrLn)
import Control.Monad.Except
import System.Environment
import System.Exit
import System.IO(stderr)
import Options.Applicative
import Text.RegexPR

import qualified Data.Text as Text
import qualified Data.Text.IO as Text
import qualified Data.ByteString.Char8 as BS

import Web.VKHS.Imports
import Web.VKHS
import Web.VKHS.Types
import Web.VKHS.Client as Client
import Web.VKHS.Monad hiding (catch)
import Web.VKHS.API as API

import Util

env_access_token = "VKQ_ACCESS_TOKEN"

-- | Options to query VK database
data DBOptions = DBOptions {
    db_countries :: Bool
  , db_cities :: Bool
  } deriving(Show)

data APIOptions = APIOptions {
    a_method :: String
  , a_args :: String
  , a_pretty :: Bool
  } deriving(Show)

data LoginOptions = LoginOptions {
    l_eval :: Bool
  } deriving(Show)

data PhotoOptions = PhotoOptions {
    p_listAlbums :: Bool
  , p_uploadServer :: Bool
  } deriving(Show)

data Options
  = Login GenericOptions LoginOptions
  | API GenericOptions APIOptions
  | Music GenericOptions MusicOptions
  | UserQ GenericOptions UserOptions
  | WallQ GenericOptions WallOptions
  | GroupQ GenericOptions GroupOptions
  | DBQ GenericOptions DBOptions
  | Photo GenericOptions PhotoOptions
  deriving(Show)

toMaybe :: (Functor f) => f String -> f (Maybe String)
toMaybe = fmap (\s -> if s == "" then Nothing else Just s)

opts m =
  let

      -- genericOptions_ :: Parser GenericOptions
      genericOptions_ puser ppass = GenericOptions
        <$> (pure $ o_login_host defaultOptions)
        <*> (pure $ o_api_host defaultOptions)
        <*> (pure $ o_port defaultOptions)
        <*> flag False True (long "verbose" <> help "Be verbose")
        <*> (pure $ o_use_https defaultOptions)
        <*> fmap (read . tunpack) (tpack <$> strOption (value (show $ o_max_request_rate_per_sec defaultOptions) <> long "req-per-sec" <> metavar "N" <> help "Max number of requests per second"))
        <*> flag True False (long "interactive" <> help "Allow interactive queries")

        <*> (AppID <$> strOption (long "appid" <> metavar "APPID" <> value "3128877" <> help "Application ID, defaults to VKHS" ))
        <*> puser
        <*> ppass
        <*> strOption (short 'a' <> m <> metavar "ACCESS_TOKEN" <>
              help ("Access token. Honores " ++ env_access_token ++ " environment variable"))
        <*> strOption (long "access-token-file" <> value "" <> metavar "FILE" <>
              help ("Filename to store actual access token, should be used to pass its value between sessions"))

      genericOptions = genericOptions_
        (strOption (value "" <> long "user" <> metavar "USER" <> help "User name or email"))
        (strOption (value "" <> long "pass" <> metavar "PASS" <> help "User password"))

      genericOptions_login = genericOptions_
        (argument str (metavar "USER" <> help "User name or email"))
        (argument str (metavar "PASS" <> help "User password"))


      api_cmd = (info (API <$> genericOptions <*> (APIOptions
        <$> argument str (metavar "METHOD" <> help "Method name")
        <*> argument str (metavar "PARAMS" <> help "Method arguments, KEY=VALUE[,KEY2=VALUE2[,,,]]")
        <*> switch (long "pretty" <> help "Pretty print resulting JSON")))
            ( progDesc "Call VK API method" ))

  in hsubparser (
       command "login" (info (Login <$> genericOptions_login <*> (LoginOptions
      <$> flag False True (long "eval" <> help "Print in shell-friendly format")
      ))
      ( progDesc "Login and print access token" ))
    <> command "call" api_cmd
    <> command "api" api_cmd
    <> command "music" (info ( Music <$> genericOptions <*> (MusicOptions
      <$> switch (long "list" <> short 'l' <> help "List music files")
      <*> strOption
        ( metavar "STR"
        <> long "query" <> short 'q' <> value [] <> help "Query string")
      <*> strOption
        ( metavar "FORMAT"
        <> short 'f'
        <> value "%i %U\t%t"
        <> help "Listing format, supported tags: %i %o %a %t %d %u"
        )
      <*> strOption
        ( metavar "FORMAT"
        <> short 'F'
        <> value "%i_%a_%t"
        <> help ("Output format, supported tags:" ++ (listTags mr_tags))
        )
      <*> toMaybe (strOption (metavar "DIR" <> short 'o' <> help "Output directory" <> value ""))
      <*> many (argument str (metavar "RECORD_ID" <> help "Download records"))
      <*> flag False True (long "skip-existing" <> help "Don't download existing files")
      ))
      ( progDesc "List or download music files"))

    <> command "user" (info ( UserQ <$> genericOptions <*> (UserOptions
      <$> strOption (long "query" <> short 'q' <> help "String to query")
      ))
      ( progDesc "Extract various user information"))

    <> command "wall" (info ( WallQ <$> genericOptions <*> (WallOptions
      <$> strOption (long "id" <> short 'i' <> help "Owner id")
      ))
      ( progDesc "Extract wall information"))

    <> command "group" (info ( GroupQ <$> genericOptions <*> (GroupOptions
      <$> strOption (long "query" <> short 'q' <> value [] <> help "Group search string")
      <*> strOption
        ( metavar "FORMAT"
        <> short 'F'
        <> value "%i %m %n %u"
        <> help ("Output format, supported tags:" ++ (listTags gr_tags))
        )
      ))
      ( progDesc "Extract groups information"))

    <> command "db" (info ( DBQ <$> genericOptions <*> (DBOptions
      <$> flag False True (long "list-countries" <> help "List known countries")
      <*> flag False True (long "list-cities" <> help "List known cities")
      ))
      ( progDesc "Extract generic DB information"))

    <> command "photo" (info ( Photo <$> genericOptions <*> (PhotoOptions
      <$> flag False True (long "list-albums" <> help "List Albums")
      <*> flag False True (long "upload-server" <> help "Get upload server")
      ))
      ( progDesc "Photo-related queries"))
    )

main :: IO ()
main = ( do
  m <- maybe (value "") (value) <$> lookupEnv env_access_token
  o <- execParser (info (helper <*> opts m) (fullDesc <> header "VKontakte social network tool"))
  r <- runExceptT (cmd o)
  case r of
    Left err -> do
      hPutStrLn stderr err
      exitFailure
    Right _ -> do
      return ()
  )`catch` (\(e::SomeException) -> do
    putStrLn $ Text.pack (show e)
    exitFailure
  )

{-
  ____ _     ___
 / ___| |   |_ _|
| |   | |    | |
| |___| |___ | |
 \____|_____|___|

 -}

cmd :: Options -> ExceptT Text IO ()

-- Login
cmd (Login go LoginOptions{..}) = do
  AccessToken{..} <- runLogin go
  case l_eval of
    True -> liftIO $ putStrLn $ Text.pack $ printf "export %s=%s\n" env_access_token at_access_token
    False -> liftIO $ putStrLn $ Text.pack at_access_token

-- API / CALL
cmd (API go APIOptions{..}) = do
  runAPI go $ do
    x <- apiJ a_method (map (id *** tpack) $ splitFragments "," "=" a_args)
    if a_pretty
      then do
        liftIO $ BS.putStrLn $ jsonEncodePretty x
      else
        liftIO $ BS.putStrLn $ jsonEncode x
  return ()

cmd (Music go@GenericOptions{..} mo@MusicOptions{..}) = do
  error "VK disabled audio API since 2016/11."

-- Query groups files
cmd (GroupQ go (GroupOptions{..}))

  |not (null g_search_string) = do

    runAPI go $ do

      (Sized cnt grs) <- groupSearch (tpack g_search_string)

      forM_ grs $ \gr -> do
        liftIO $ printf "%s\n" (gr_format g_output_format gr)

cmd (DBQ go (DBOptions{..}))

  |db_countries = do

    runAPI go $ do

      (Sized cnt cs) <- getCountries

      forM_ cs $ \Country{..} -> do
        liftIO $ Text.putStrLn $ Text.concat [ tshow co_int, "\t",  co_title]

  |db_cities = do
    error "not implemented"

cmd (Photo go PhotoOptions{..})

  |p_listAlbums = do
    runAPI go $ do
      (Sized cnt als) <- getAlbums Nothing
      forM_ als $ \Album{..} -> do
        liftIO $ Text.putStrLn $ Text.concat [ tshow al_id, "\t",  al_title]

  |p_uploadServer = do
    runAPI go $ do
      (Sized cnt als) <- getAlbums Nothing
      let album = [a | a <- als, al_id a == -7]
      case album of
        [a] -> do
          PhotoUploadServer{..} <- getPhotoUploadServer a
          liftIO $ Text.putStrLn pus_upload_url
        _ ->
          error "Ivalid album"

  |otherwise = do
    error "invalid command line arguments"