{-# LANGUAGE RecordWildCards #-}

module Potato.Flow.SEltMethods where

import           Relude

import           Potato.Flow.Math
import           Potato.Flow.Methods.LineDrawer
import           Potato.Flow.Methods.TextCommon
import           Potato.Flow.Methods.Types
import           Potato.Flow.Owl
import Potato.Flow.RenderCache
import           Potato.Flow.OwlItem
import           Potato.Flow.SElts
import           Potato.Flow.Types

import           Data.Dependent.Sum             (DSum ((:=>)))
import qualified Data.Map                       as Map
import           Data.Maybe                     (fromJust)
import qualified Data.Text                      as T
import qualified Potato.Data.Text.Zipper        as TZ
import Control.Exception (assert)


-- DisplayLines tag is Int, 0 for no cursor 1 for cursor
noTrailngCursorDisplayLines :: Int -> TextAlign -> T.Text -> TZ.DisplayLines Int
noTrailngCursorDisplayLines width alignment text = r where
  -- force TZ to top so that displayLinesWithAlignment doesn't create trailing space for cursor
  tz = TZ.top (TZ.fromText text)

  -- hack to get rid of trailing cursor if text is ""
  r = if T.null text
    then TZ.DisplayLines {
        _displayLines_spans = []
        , _displayLines_offsetMap = Map.empty
        , _displayLines_cursorPos   = (0,0)
      }
    else TZ.displayLinesWithAlignment (convertTextAlignToTextZipperTextAlignment alignment) width 0 1 tz

makeDisplayLinesFromSBox :: SBox -> TZ.DisplayLines Int
makeDisplayLinesFromSBox sbox = r where
  alignment = _textStyle_alignment . _sBoxText_style . _sBox_text $ sbox
  text = _sBoxText_text . _sBox_text $ sbox
  LBox _ (V2 width' _) = _sBox_box sbox
  width = case _sBox_boxType sbox of
    SBoxType_BoxText   -> max 0 (width'-2)
    SBoxType_NoBoxText -> width'
    _                  -> error "wrong type"
  r = noTrailngCursorDisplayLines width alignment text



-- TODO DELETE use doesOwlSubItemIntersectBox instead
doesSEltIntersectBox_DEPRECATED :: LBox -> SElt -> Bool
doesSEltIntersectBox_DEPRECATED lbox selt = case selt of
  SEltNone                     -> False
  SEltFolderStart              -> False
  SEltFolderEnd                -> False
  SEltBox x                    -> does_lBox_intersect_include_zero_area lbox (_sBox_box x)
  SEltTextArea x                   -> does_lBox_intersect_include_zero_area lbox (_sTextArea_box x)
  -- TODO this is wrong, do it correctly...
  -- we use does_lBox_intersect since it's impossible for a SAutoLine to have zero sized box
  SEltLine sline -> does_lBox_intersect lbox (fromJust $ getSEltBox_naive (SEltLine sline))

doesSEltIntersectPoint :: XY -> SElt -> Bool
doesSEltIntersectPoint pos selt = doesSEltIntersectBox_DEPRECATED (LBox pos (V2 1 1)) selt

getSEltSuperStyle :: SElt -> Maybe SuperStyle
getSEltSuperStyle selt = case selt of
  SEltBox SBox {..}       -> Just _sBox_superStyle
  SEltLine SAutoLine {..} -> Just _sAutoLine_superStyle
  _                       -> Nothing

getSEltLabelSuperStyle :: SEltLabel -> Maybe SuperStyle
getSEltLabelSuperStyle (SEltLabel _ x) = getSEltSuperStyle x

getSEltLineStyle :: SElt -> Maybe LineStyle
getSEltLineStyle selt = case selt of
  SEltLine SAutoLine {..} -> Just _sAutoLine_lineStyle
  _                       -> Nothing

getSEltLineStyleEnd :: SElt -> Maybe LineStyle
getSEltLineStyleEnd selt = case selt of
  SEltLine SAutoLine {..} -> Just _sAutoLine_lineStyleEnd
  _                       -> Nothing

getSEltLabelLineStyle :: SEltLabel -> Maybe LineStyle
getSEltLabelLineStyle (SEltLabel _ x) = getSEltLineStyle x

getSEltLabelLineStyleEnd :: SEltLabel -> Maybe LineStyle
getSEltLabelLineStyleEnd (SEltLabel _ x) = getSEltLineStyleEnd x


getSEltBoxTextStyle :: SElt -> Maybe TextStyle
getSEltBoxTextStyle = \case
  SEltBox SBox {..}         -> Just . _sBoxText_style $ _sBox_text
  _ -> Nothing

getSEltLabelBoxTextStyle :: SEltLabel -> Maybe TextStyle
getSEltLabelBoxTextStyle (SEltLabel _ x) = getSEltBoxTextStyle x

getSEltBoxType :: SElt -> Maybe SBoxType
getSEltBoxType = \case
  SEltBox SBox {..} -> Just _sBox_boxType
  _ -> Nothing

getSEltLabelBoxType :: SEltLabel -> Maybe SBoxType
getSEltLabelBoxType (SEltLabel _ x) = getSEltBoxType x

sBox_drawer :: SBox -> SEltDrawer
sBox_drawer sbox@SBox {..} = r where
  CanonicalLBox _ _ lbox@(LBox (V2 x y) (V2 w h)) = canonicalLBox_from_lBox _sBox_box

  titlewidth = max 0 (w-2)

  fillfn _ = case _superStyle_fill _sBox_superStyle of
    FillStyle_Simple c -> Just c
    FillStyle_Blank    -> Nothing

  rfntext (V2 x' y') = case _sBox_boxType of
    SBoxType_Box -> Nothing
    SBoxType_NoBox -> Nothing
    _ -> outputChar where

      -- 😰😰😰 for now we just do the below for every cell
      dl = makeDisplayLinesFromSBox sbox

      offs = case _sBox_boxType of
        SBoxType_NoBoxText -> (0,0)
        _                  -> (1,1)

      outputChar = displayLinesToChar (x, y) dl (x', y') offs

  -- TODO test
  rfnlabel (V2 x' y') = case _sBoxTitle_title _sBox_title of
    Nothing -> Nothing
    Just title -> outputChar where
      -- TODO we want to crop instead of wrap here
      -- however using infinite width trick will break AlignRight :(
      dl = noTrailngCursorDisplayLines titlewidth (_sBoxTitle_align _sBox_title) title
      -- note that y' will ultimately resolve to a yindex of 0 inside of displayLinesToChar
      outputChar = displayLinesToChar (x, y) dl (x', y') (1,0)

  rfnnoborder pt
    | not (does_lBox_contains_XY lbox pt) = Nothing
    | otherwise = case rfntext pt of
      -- 'Just Nothing' means don't use fill char (this happens when there are wide chars)
      Just mx -> mx
      Nothing -> fillfn pt

  rfnborder pt@(V2 x' y')
    | not (does_lBox_contains_XY lbox pt) = Nothing
    | w == 1 && h == 1 = _superStyle_point _sBox_superStyle
    | w == 1 = _superStyle_vertical _sBox_superStyle
    | h == 1 = _superStyle_horizontal _sBox_superStyle
    | x' == x && y' == y = _superStyle_tl _sBox_superStyle
    | x' == x && y' == y+h-1 = _superStyle_bl _sBox_superStyle
    | x' == x+w-1 && y' == y = _superStyle_tr _sBox_superStyle
    | x' == x+w-1 && y' == y+h-1 = _superStyle_br _sBox_superStyle
    | x' == x || x' == x+w-1 = _superStyle_vertical _sBox_superStyle
    -- label shows up at top horizontal portion
    | y' == y = case rfnlabel pt of
      Nothing    -> _superStyle_horizontal _sBox_superStyle
      Just pchar -> pchar
    | y' == y+h-1 = _superStyle_horizontal _sBox_superStyle
    | otherwise = rfnnoborder pt

  r = SEltDrawer {
      _sEltDrawer_box = const lbox
      , _sEltDrawer_renderFn = \_ -> case _sBox_boxType of
        SBoxType_NoBoxText -> rfnnoborder
        SBoxType_NoBox     -> rfnnoborder
        _                  -> rfnborder
      
      -- TODO 
      , _sEltDrawer_maxCharWidth = 1
    }

sTextArea_drawer :: STextArea -> SEltDrawer
sTextArea_drawer STextArea {..} = r where

  lbox@(LBox p _) = _sTextArea_box

  renderfn p' = outputChar where
    inbounds = does_lBox_contains_XY lbox p'
    outputChar = if inbounds
      then case Map.lookup (p' - p) _sTextArea_text of
        Nothing -> if _sTextArea_transparent
          then Nothing
          else Just ' '
        Just c -> Just c
      else Nothing

  r = SEltDrawer {
      _sEltDrawer_box = const lbox
      , _sEltDrawer_renderFn = \_ -> renderfn

      -- TODO
      , _sEltDrawer_maxCharWidth = 1
    }

-- NOTE that there is not a 1-1 mapping between `OwlSubItem` and `OwlItemCache` as the `OwlItemCache` is dependent on the OwlTree
-- this function assumes that you are requesting the drawer with the intent of passing in an OwlTree
-- TODO it would have been better for SEltDrawer to be created based on an OwlTree rather than return a function that takes an OwlTree
getDrawerWithCache :: OwlSubItem -> Maybe OwlItemCache -> SEltDrawer
getDrawerWithCache osubitem mcache = case osubitem of 
  OwlSubItemNone        -> nilDrawer
  OwlSubItemFolder _ -> nilDrawer
  OwlSubItemBox sbox    -> sBox_drawer sbox
  OwlSubItemLine sline -> case mcache of 
    Just (OwlItemCache_Line lars _) -> sSimpleLineNewRenderFn sline (Just lars)
    Nothing -> sSimpleLineNewRenderFn sline Nothing
    _ -> assert False (sSimpleLineNewRenderFn sline Nothing)
  OwlSubItemTextArea stextarea  -> sTextArea_drawer stextarea

-- TODO pass in cache here
getDrawer :: OwlSubItem -> SEltDrawer
getDrawer = \case
  OwlSubItemNone        -> nilDrawer
  OwlSubItemFolder _ -> nilDrawer
  OwlSubItemBox sbox    -> sBox_drawer sbox
  OwlSubItemLine sline -> sSimpleLineNewRenderFn sline Nothing
  OwlSubItemTextArea stextarea  -> sTextArea_drawer stextarea
  {-
  where
    potatoDrawer = SEltDrawer {
        _sEltDrawer_box = const $ fromJust (getSEltBox_naive selt)
        , _sEltDrawer_renderFn =  makePotatoRenderer $ fromJust (getSEltBox_naive selt)
      }
  -}

getDrawerFromSEltForTest :: SElt -> SEltDrawer
getDrawerFromSEltForTest = getDrawer . sElt_to_owlSubItem

updateOwlSubItemCache :: (HasOwlTree a) => a -> OwlSubItem -> Maybe OwlItemCache
updateOwlSubItemCache ot x = r where
  r = case x of
    -- TODO use sAutoLine_to_lineAnchorsForRenderList here instead
    (OwlSubItemLine sline) -> cache where
      cache = Just $ OwlItemCache_Line (sSimpleLineNewRenderFnComputeCache ot sline) prerender
      seltdrawer = getDrawerWithCache x cache
      prerender = makePreRender ot seltdrawer 
    _ -> Just $ OwlItemCache_Generic prerender where
      seltdrawer = getDrawerWithCache x Nothing
      prerender = makePreRender ot seltdrawer 


-- TODO move modify methods to another file

modify_sAutoLineConstraint_with_cBoundingBox :: Bool -> SAutoLineConstraint -> CBoundingBox -> SAutoLineConstraint
modify_sAutoLineConstraint_with_cBoundingBox isDo constraint CBoundingBox {..} = case constraint of
  SAutoLineConstraintFixed xy -> SAutoLineConstraintFixed $ modifyDelta isDo xy (_deltaLBox_translate _cBoundingBox_deltaBox)

modify_sElt_with_cBoundingBox :: Bool -> SElt -> CBoundingBox -> SElt
modify_sElt_with_cBoundingBox isDo selt cbb@CBoundingBox {..} = case selt of
  SEltBox sbox  -> SEltBox $ sbox {
      _sBox_box = modifyDelta isDo (_sBox_box sbox) _cBoundingBox_deltaBox
    }
  -- TODO handle resize parameter
  SEltLine sline@SAutoLine {..} -> SEltLine $ sline {
      _sAutoLine_start = modifyDelta isDo _sAutoLine_start
        (_deltaLBox_translate _cBoundingBox_deltaBox)
      , _sAutoLine_end = modifyDelta isDo _sAutoLine_end
        (_deltaLBox_translate _cBoundingBox_deltaBox)
      , _sAutoLine_midpoints = fmap (\slc -> modify_sAutoLineConstraint_with_cBoundingBox isDo slc cbb) _sAutoLine_midpoints
    }
  SEltTextArea stext -> SEltTextArea $ stext {
      _sTextArea_box     = modifyDelta isDo (_sTextArea_box stext) _cBoundingBox_deltaBox
    }
  x          -> x

modify_sElt_with_cSuperStyle :: Bool -> SElt -> CSuperStyle -> SElt
modify_sElt_with_cSuperStyle isDo selt (CSuperStyle style) = case selt of
  SEltBox sbox -> SEltBox $ sbox {
      _sBox_superStyle = modifyDelta isDo (_sBox_superStyle sbox) style
    }
  -- TODO handle resize parameter
  SEltLine sline -> SEltLine $ sline {
      _sAutoLine_superStyle = modifyDelta isDo (_sAutoLine_superStyle sline) style
    }
  _ -> error $ "Controller - SElt type mismatch: CTagSuperStyle - " <> show selt
  -- maybe we want silent failure case in the future, so you can easily restyle a big selection in bulk
  --x -> x

-- TODO DELETE use llama instead
modify_sElt_with_cLineStyle :: Bool -> SElt -> CLineStyle -> SElt
modify_sElt_with_cLineStyle isDo selt (CLineStyle style) = case selt of
  SEltLine sline -> SEltLine $ sline {
      _sAutoLine_lineStyle = modifyDelta isDo (_sAutoLine_lineStyle sline) style
    }
  _ -> error $ "Controller - SElt type mismatch: CTagLineStyle - " <> show selt
  -- maybe we want silent failure case in the future, so you can easily restyle a big selection in bulk
  --x -> x

modify_sElt_with_cTextStyle :: Bool -> SElt -> CTextStyle -> SElt
modify_sElt_with_cTextStyle isDo selt (CTextStyle style) = case selt of
  SEltBox sbox -> SEltBox $ sbox {
      _sBox_text = (_sBox_text sbox) {
          _sBoxText_style = modifyDelta isDo (_sBoxText_style . _sBox_text $ sbox) style
        }
    }
  _ -> error $ "Controller - SElt type mismatch: CTagBoxTextStyle - " <> show selt
  -- maybe we want silent failure case in the future, so you can easily restyle a big selection in bulk
  --x -> x

modify_sEltBox_label_with_cTextAlign :: Bool -> SElt -> CTextAlign -> SElt
modify_sEltBox_label_with_cTextAlign isDo selt (CTextAlign align) = case selt of
  SEltBox sbox -> SEltBox $ sbox {
      _sBox_title = sboxtitle {
          _sBoxTitle_align = modifyDelta isDo (_sBoxTitle_align sboxtitle) align
        }
    } where
      sboxtitle = _sBox_title sbox
  _ -> error $ "Controller - SElt type mismatch: CTagBoxLabelAlignment - " <> show selt
  -- maybe we want silent failure case in the future, so you can easily restyle a big selection in bulk
  --x -> x

modify_sEltBox_label_with_cMaybeText :: Bool -> SElt -> CMaybeText -> SElt
modify_sEltBox_label_with_cMaybeText isDo selt (CMaybeText text) = case selt of
  SEltBox sbox -> SEltBox $ sbox {
      _sBox_title = sboxtitle {
          _sBoxTitle_title = modifyDelta isDo (_sBoxTitle_title sboxtitle) text
        }
    } where
      sboxtitle = _sBox_title sbox
  _ -> error $ "Controller - SElt type mismatch: CTagBoxLabelAlignment - " <> show selt

modify_sEltTextArea_with_cTextArea :: Bool -> SElt -> CTextArea -> SElt
modify_sEltTextArea_with_cTextArea isDo selt (CTextArea dt) = case selt of
  SEltTextArea stextarea -> SEltTextArea $ stextarea {
      _sTextArea_text = modifyDelta isDo (_sTextArea_text stextarea) dt
    }
  _ -> error $ "Controller - SElt type mismatch: CTagTextArea - " <> show selt

modify_sEltTextArea_with_cTextAreaToggle :: Bool -> SElt -> CTextAreaToggle -> SElt
modify_sEltTextArea_with_cTextAreaToggle isDo selt (CTextAreaToggle toggle) = case selt of
  -- double toggle is idempotent but we disallow it for now
  SEltTextArea _ -> error $ "Controller - SElt type mismatch: CTagTextAreaToggle - " <> show selt
  x -> modifyDelta isDo x toggle


modifyDelta :: (Delta x dx) => Bool -> x ->  dx -> x
modifyDelta isDo x dx = if isDo
  then plusDelta x dx
  else minusDelta x dx

updateFnFromController :: Bool -> Controller -> (SEltLabel -> SEltLabel)
updateFnFromController isDo = \case
  (CTagRename :=> Identity d) -> \seltl -> modifyDelta isDo seltl d
  (CTagLine :=> Identity d) -> \(SEltLabel sname selt) -> case selt of
    SEltLine s -> SEltLabel sname (SEltLine $ modifyDelta isDo s d)
    _ -> error $ "Controller - SElt type mismatch: CTagLine - " <> show selt
  (CTagBoxText :=> Identity d) -> \(SEltLabel sname selt) -> case selt of
    SEltBox s -> SEltLabel sname (SEltBox $ modifyDelta isDo s d)
    _ -> error $ "Controller - SElt type mismatch: CTagBoxText - " <> show selt
  (CTagBoxType :=> Identity d) -> \(SEltLabel sname selt) -> case selt of
    SEltBox s -> SEltLabel sname (SEltBox $ modifyDelta isDo s d)
    _ -> error $ "Controller - SElt type mismatch: CTagBoxText - " <> show selt
  (CTagBoundingBox :=> Identity d) -> \(SEltLabel sname selt) ->
    SEltLabel sname (modify_sElt_with_cBoundingBox isDo selt d)
  (CTagSuperStyle :=> Identity d) -> \(SEltLabel sname selt) ->
    SEltLabel sname (modify_sElt_with_cSuperStyle isDo selt d)
  (CTagLineStyle :=> Identity d) -> \(SEltLabel sname selt) ->
    SEltLabel sname (modify_sElt_with_cLineStyle isDo selt d)
  (CTagBoxTextStyle :=> Identity d) -> \(SEltLabel sname selt) ->
    SEltLabel sname (modify_sElt_with_cTextStyle isDo selt d)

  (CTagBoxLabelAlignment :=> Identity d) -> \(SEltLabel sname selt) ->
    SEltLabel sname (modify_sEltBox_label_with_cTextAlign isDo selt d)
  (CTagBoxLabelText :=> Identity d) -> \(SEltLabel sname selt) ->
    SEltLabel sname (modify_sEltBox_label_with_cMaybeText isDo selt d)

  (CTagTextArea :=> Identity d) -> \(SEltLabel sname selt) ->
    SEltLabel sname (modify_sEltTextArea_with_cTextArea isDo selt d)
  (CTagTextAreaToggle :=> Identity d) -> \(SEltLabel sname selt) ->
    SEltLabel sname (modify_sEltTextArea_with_cTextAreaToggle isDo selt d)


-- | helper method used in copy pasta
offsetSEltTree :: XY -> SEltTree -> SEltTree
offsetSEltTree offset stree = r where
  op = CBoundingBox (DeltaLBox offset 0)
  offsetfn (rid, seltl) = (rid, updateFnFromController True (CTagBoundingBox :=> Identity op) seltl)
  r = fmap offsetfn stree