-- Copyright (c) 2016-present, Facebook, Inc.
-- All rights reserved.
--
-- This source code is licensed under the BSD-style license found in the
-- LICENSE file in the root directory of this source tree.


{-# LANGUAGE NamedFieldPuns #-}
{-# LANGUAGE NoRebindableSyntax #-}
{-# LANGUAGE OverloadedStrings #-}

module Duckling.Debug
  ( allParses
  , debug
  , debugCustom
  , fullParses
  , ptree
  ) where

import Data.Maybe
import Data.Text (Text)
import Prelude
import qualified Data.HashSet as HashSet
import qualified Data.Text as Text
import qualified Data.Text.IO as Text

import Duckling.Api
import Duckling.Dimensions.Types
import Duckling.Engine
import Duckling.Locale
import Duckling.Resolve
import Duckling.Rules
import Duckling.Testing.Types
import Duckling.Types

-- -----------------------------------------------------------------
-- API

debug :: Locale -> Text -> [Seal Dimension] -> IO [Entity]
debug locale = debugCustom testContext {locale = locale} testOptions

allParses :: Locale -> Text -> [Seal Dimension] -> IO [Entity]
allParses l sentence targets = debugTokens sentence $ parses l sentence targets

fullParses :: Locale -> Text -> [Seal Dimension] -> IO [Entity]
fullParses l sentence targets = debugTokens sentence .
  filter (\Resolved{range = Range start end} -> start == 0 && end == n) $
  parses l sentence targets
  where
    n = Text.length sentence

debugCustom :: Context -> Options -> Text -> [Seal Dimension] -> IO [Entity]
debugCustom context options sentence targets = debugTokens sentence .
  analyze sentence context options $ HashSet.fromList targets

ptree :: Text -> Entity -> IO ()
ptree sentence Entity {enode} = pnode sentence 0 enode

-- -----------------------------------------------------------------
-- Internals

parses :: Locale -> Text -> [Seal Dimension] -> [ResolvedToken]
parses l sentence targets = flip filter tokens $
  \Resolved{node = Node{token = (Token d _)}} ->
    case targets of
      [] -> True
      _ -> elem (Seal d) targets
  where
    tokens = parseAndResolve rules sentence testContext {locale = l} testOptions
    rules = rulesFor l $ HashSet.fromList targets

debugTokens :: Text -> [ResolvedToken] -> IO [Entity]
debugTokens sentence tokens = do
  mapM_ (ptree sentence) entities
  return entities
  where entities = map (formatToken sentence) tokens

pnode :: Text -> Int -> Node -> IO ()
pnode sentence depth Node {children, rule, nodeRange = Range start end} = do
  Text.putStrLn out
  mapM_ (pnode sentence (depth + 1)) children
  where
    out = Text.concat [ Text.replicate depth "-- ", name, " (", body, ")" ]
    name = fromMaybe "regex" rule
    body = Text.drop start $ Text.take end sentence