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

module Main where

import Control.Exception (SomeException(..),catch,bracket)
import Control.Monad
import Control.Monad.Trans
import Control.Monad.Trans.Either
import Data.Maybe
import Data.List
import Data.Char
import Data.Text(Text(..),pack)
import qualified Data.Text as Text
import qualified Data.Text.IO as Text
import Data.ByteString.Char8 (ByteString)
import qualified Data.ByteString.Char8 as BS
import Options.Applicative
import System.Environment
import System.Exit
import System.IO
import Text.RegexPR
import Text.Printf

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"

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

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

data Options
  = Login GenericOptions LoginOptions
  | API GenericOptions APIOptions
  | Music GenericOptions MusicOptions
  | UserQ GenericOptions UserOptions
  | WallQ GenericOptions WallOptions
  | GroupQ GenericOptions GroupOptions
  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 (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"))

      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[,,,]]")))
        ( progDesc "Call VK API method" ))

  in subparser (
       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 "%o_%i %U\t%t"
        <> help "Listing format, supported tags: %i %o %a %t %d %u"
        )
      <*> strOption
        ( metavar "FORMAT"
        <> short 'F'
        <> value "%o_%i %U\t%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"))
    )

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 <- runEitherT (cmd o)
  case r of
    Left err -> do
      hPutStrLn stderr err
      exitFailure
    Right _ -> do
      return ()
  )`catch` (\(e::SomeException) -> do
    putStrLn $ (show e)
    exitFailure
  )

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

 -}

cmd :: Options -> EitherT String IO ()

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

-- API
cmd (API go APIOptions{..}) = do
  runAPI go $ do
    x <- apiJ a_method (splitFragments "," "=" a_args)
    liftIO $ putStrLn $ show x
  return ()

cmd (Music go@GenericOptions{..} mo@MusicOptions{..})

  -- Query music files
  |not (null m_search_string) = do
    runAPI go $ do
      API.Response _ (SizedList len ms) <- api "audio.search" [("q",m_search_string), ("count", "1000")]
      forM_ ms $ \m -> do
        io $ printf "%s\n" (mr_format m_output_format m)
      io $ printf "total %d\n" len

  -- List music files
  |m_list_music = do
    runAPI go $ do
      (API.Response _ (ms :: [MusicRecord])) <- api "audio.get" [("q",m_search_string)]
      forM_ ms $ \m -> do
        io $ printf "%s\n" (mr_format m_output_format m)

  -- Download music files
  |not (null m_records_id) = do
    let out_dir = fromMaybe "." m_out_dir
    runAPI go $ do
      (API.Response _ (ms :: [MusicRecord])) <- api "audio.getById" [("audios", concat $ intersperse "," m_records_id)]
      forM_ ms $ \mr@MusicRecord{..} -> do
        (f, mh) <- liftIO $ openFileMR mo mr
        case mh of
          Just h -> do
            u <- ensure (pure $ Client.urlFromString mr_url_str)
            r <- Client.downloadFileWith u (BS.hPut h)
            io $ printf "%d_%d\n" mr_owner_id mr_id
            io $ printf "%s\n" mr_title
            io $ printf "%s\n" f
          Nothing -> do
            io $ hPutStrLn stderr ("File " ++ f ++ " already exist, skipping")
        return ()


-- Download audio files
-- cmd (Options v (Music (MO act False [] _ ofmt odir rid sk))) = do
--   let e = (envcall act) { verbose = v }
--   Response (ms :: [MusicRecord]) <- api_ e "audio.getById" [("audios", concat $ intersperse "," rid)]
--   forM_ ms $ \m -> do
--     (fp, mh) <- openFileMR odir sk ofmt m
--     case mh of
--       Just h -> do
--         r <- vk_curl_file e (url m) $ \ bs -> do
--           BS.hPut h bs
--         checkRight r
--         printf "%d_%d\n" (owner_id m) (aid m)
--         printf "%s\n" (title m)
--         printf "%s\n" fp
--       Nothing -> do
--         hPutStrLn stderr (printf "File %s already exist, skipping" fp)
--     return ()

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

  |not (null g_search_string) = do

    runAPI go $ do

      (Sized cnt grs) <- runGroupSearch g_search_string

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