-- | This module implements a "flattening" pass over RichText 'Inline'
-- values. This means that a tree structure such as
--
-- @
--   EStrong
--     [ EStrikethrough
--       [ EText "inside"
--       ]
--     , EText "outside"
--     ]
-- @
--
-- will be converted into a "flat" representation without a tree
-- structure so that the style information encoded in the tree is
-- available at each node:
--
-- @
--   [
--     [ SingleInline (FlattenedInline (FText "inside") [Strong, Strikethrough] Nothing
--     , SingleInline (FlattenedInline (FText "outside") [Strong] Nothing
--     ]
--   ]
-- @
--
-- The outer sequence is a sequence of lines (since inline lists can
-- introduce line breaks). Each inner sequence is a single line.
-- Each 'SingleInline' can be rendered as-is; if a 'NonBreaking' is
-- encountered, that group of inlines should be treated as a unit for
-- the purposes of line-wrapping (to happen in the Wrap module). The
-- above representation example shows how the tree path including the
-- 'EStrong' and 'EStrikethrough' nodes is flattened into a list of
-- styles to accompany each inline value. This makes it trivial to carry
-- that style information along with each node during line-wrapping
-- rather than needing to deal with the tree structure.
module Matterhorn.Draw.RichText.Flatten
  ( FlattenedContent(..)
  , FlattenedInline(..)
  , InlineStyle(..)
  , FlattenedValue(..)
  , flattenInlineSeq
  )
where

import           Prelude ()
import           Matterhorn.Prelude

import           Control.Monad.Reader
import           Control.Monad.State
import           Data.List ( nub )
import qualified Data.Sequence as Seq
import           Data.Sequence ( ViewL(..)
                               , ViewR(..)
                               , (<|)
                               , (|>)
                               )
import qualified Data.Set as Set
import qualified Data.Text as T

import           Matterhorn.Constants ( normalChannelSigil )
import           Matterhorn.Types ( HighlightSet(..), SemEq(..), addUserSigil )
import           Matterhorn.Types.RichText


-- | A piece of text in a sequence of flattened RichText elements. This
-- type represents the lowest-level kind of data that we can get from a
-- rich text document.
data FlattenedContent =
    FText Text
    -- ^ Some text
    | FSpace
    -- ^ A space
    | FUser Text
    -- ^ A user reference
    | FChannel Text
    -- ^ A channel reference
    | FEmoji Text
    -- ^ An emoji
    | FEditSentinel Bool
    -- ^ An "edited" marking
    deriving (FlattenedContent -> FlattenedContent -> Bool
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: FlattenedContent -> FlattenedContent -> Bool
$c/= :: FlattenedContent -> FlattenedContent -> Bool
== :: FlattenedContent -> FlattenedContent -> Bool
$c== :: FlattenedContent -> FlattenedContent -> Bool
Eq, Int -> FlattenedContent -> ShowS
[FlattenedContent] -> ShowS
FlattenedContent -> String
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [FlattenedContent] -> ShowS
$cshowList :: [FlattenedContent] -> ShowS
show :: FlattenedContent -> String
$cshow :: FlattenedContent -> String
showsPrec :: Int -> FlattenedContent -> ShowS
$cshowsPrec :: Int -> FlattenedContent -> ShowS
Show)

-- | A flattened inline value.
data FlattenedInline a =
    FlattenedInline { forall a. FlattenedInline a -> FlattenedContent
fiValue :: FlattenedContent
                    -- ^ The content of the value.
                    , forall a. FlattenedInline a -> [InlineStyle]
fiStyles :: [InlineStyle]
                    -- ^ The styles that should be applied to this
                    -- value.
                    , forall a. FlattenedInline a -> Maybe URL
fiURL :: Maybe URL
                    -- ^ If present, the URL to which we should
                    -- hyperlink this value.
                    , forall a. FlattenedInline a -> Maybe a
fiName :: Maybe a
                    -- ^ The resource name, if any, that should be used
                    -- to make this inline clickable once rendered.
                    }
                    deriving (Int -> FlattenedInline a -> ShowS
forall a. Show a => Int -> FlattenedInline a -> ShowS
forall a. Show a => [FlattenedInline a] -> ShowS
forall a. Show a => FlattenedInline a -> String
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [FlattenedInline a] -> ShowS
$cshowList :: forall a. Show a => [FlattenedInline a] -> ShowS
show :: FlattenedInline a -> String
$cshow :: forall a. Show a => FlattenedInline a -> String
showsPrec :: Int -> FlattenedInline a -> ShowS
$cshowsPrec :: forall a. Show a => Int -> FlattenedInline a -> ShowS
Show)

-- | A flattened value.
data FlattenedValue a =
    SingleInline (FlattenedInline a)
    -- ^ A single flattened value
    | NonBreaking (Seq (Seq (FlattenedValue a)))
    -- ^ A sequence of flattened values that MUST be kept together and
    -- never broken up by line-wrapping
    deriving (Int -> FlattenedValue a -> ShowS
forall a. Show a => Int -> FlattenedValue a -> ShowS
forall a. Show a => [FlattenedValue a] -> ShowS
forall a. Show a => FlattenedValue a -> String
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [FlattenedValue a] -> ShowS
$cshowList :: forall a. Show a => [FlattenedValue a] -> ShowS
show :: FlattenedValue a -> String
$cshow :: forall a. Show a => FlattenedValue a -> String
showsPrec :: Int -> FlattenedValue a -> ShowS
$cshowsPrec :: forall a. Show a => Int -> FlattenedValue a -> ShowS
Show)

-- | The visual styles of inline values.
data InlineStyle =
    Strong
    | Emph
    | Strikethrough
    | Code
    | Permalink
    deriving (InlineStyle -> InlineStyle -> Bool
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: InlineStyle -> InlineStyle -> Bool
$c/= :: InlineStyle -> InlineStyle -> Bool
== :: InlineStyle -> InlineStyle -> Bool
$c== :: InlineStyle -> InlineStyle -> Bool
Eq, Int -> InlineStyle -> ShowS
[InlineStyle] -> ShowS
InlineStyle -> String
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [InlineStyle] -> ShowS
$cshowList :: [InlineStyle] -> ShowS
show :: InlineStyle -> String
$cshow :: InlineStyle -> String
showsPrec :: Int -> InlineStyle -> ShowS
$cshowsPrec :: Int -> InlineStyle -> ShowS
Show)

type FlattenM n a = ReaderT (FlattenEnv n) (State (FlattenState n)) a

-- | The flatten monad state
data FlattenState a =
    FlattenState { forall a. FlattenState a -> Seq (Seq (FlattenedValue a))
fsCompletedLines :: Seq (Seq (FlattenedValue a))
                 -- ^ The lines that we have accumulated so far in the
                 -- flattening process
                 , forall a. FlattenState a -> Seq (FlattenedValue a)
fsCurLine :: Seq (FlattenedValue a)
                 -- ^ The current line we are accumulating in the
                 -- flattening process
                 , forall a. FlattenState a -> Int
fsNameIndex :: Int
                 -- ^ The index used to generate a new unique name (of
                 -- type 'a') to make a region of text clickable.
                 }

-- | The flatten monad environment
data FlattenEnv a =
    FlattenEnv { forall a. FlattenEnv a -> [InlineStyle]
flattenStyles :: [InlineStyle]
               -- ^ The styles that should apply to the current value
               -- being flattened
               , forall a. FlattenEnv a -> Maybe URL
flattenURL :: Maybe URL
               -- ^ The hyperlink URL, if any, that should be applied to
               -- the current value being flattened
               , forall a. FlattenEnv a -> HighlightSet
flattenHighlightSet :: HighlightSet
               -- ^ The highlight set to use to check for valid user or
               -- channel references
               , forall a. FlattenEnv a -> Maybe (Int -> Inline -> Maybe a)
flattenNameGen :: Maybe (Int -> Inline -> Maybe a)
               -- ^ The function to use to generate resource names
               -- for clickable inlines. If provided, this is used to
               -- determine whether a given Inline should be augmented
               -- with a resource name.
               , forall a. FlattenEnv a -> Maybe (Int -> Maybe a)
flattenNameFunc :: Maybe (Int -> Maybe a)
               -- ^ The currently active function to generate a resource
               -- name for any inline. In practice this is just the
               -- value of flattenNameGen, but partially applied with a
               -- specific Inline prior to flattening that Inline.
               }

-- | Given a sequence of inlines, flatten it into a list of lines of
-- flattened values.
--
-- The flattening process also validates user and channel references
-- against a 'HighlightSet'. For example, if an 'EUser' node is found,
-- its username argument is looked up in the 'HighlightSet'. If the
-- username is found, the 'EUser' node is preserved as an 'FUser' node.
-- Otherwise it is rewritten as an 'FText' node so that the username
-- does not get highlighted. Channel references ('EChannel') are handled
-- similarly.
--
-- The optional name generator function argument is used to assign
-- resource names to each inline that should be clickable once rendered.
-- The result of the name generator function will be stored in the
-- 'fiName' field of each 'FlattenedInline' that results from calling
-- that function on an 'Inline'.
flattenInlineSeq :: SemEq a
                 => HighlightSet
                 -> Maybe (Int -> Inline -> Maybe a)
                 -- ^ A name generator function for clickable inlines.
                 -- The integer argument is a unique (to this inline
                 -- sequence) sequence number.
                 -> Inlines
                 -> Seq (Seq (FlattenedValue a))
flattenInlineSeq :: forall a.
SemEq a =>
HighlightSet
-> Maybe (Int -> Inline -> Maybe a)
-> Inlines
-> Seq (Seq (FlattenedValue a))
flattenInlineSeq HighlightSet
hs Maybe (Int -> Inline -> Maybe a)
nameGen Inlines
is =
    forall a b. (a, b) -> b
snd forall a b. (a -> b) -> a -> b
$ forall a.
SemEq a =>
FlattenEnv a
-> Int -> Inlines -> (Int, Seq (Seq (FlattenedValue a)))
flattenInlineSeq' FlattenEnv a
initialEnv Int
0 Inlines
is
    where
        initialEnv :: FlattenEnv a
initialEnv = FlattenEnv { flattenStyles :: [InlineStyle]
flattenStyles = []
                                , flattenURL :: Maybe URL
flattenURL = forall a. Maybe a
Nothing
                                , flattenHighlightSet :: HighlightSet
flattenHighlightSet = HighlightSet
hs
                                , flattenNameGen :: Maybe (Int -> Inline -> Maybe a)
flattenNameGen = Maybe (Int -> Inline -> Maybe a)
nameGen
                                , flattenNameFunc :: Maybe (Int -> Maybe a)
flattenNameFunc = forall a. Maybe a
Nothing
                                }

flattenInlineSeq' :: SemEq a
                  => FlattenEnv a
                  -> Int
                  -> Inlines
                  -> (Int, Seq (Seq (FlattenedValue a)))
flattenInlineSeq' :: forall a.
SemEq a =>
FlattenEnv a
-> Int -> Inlines -> (Int, Seq (Seq (FlattenedValue a)))
flattenInlineSeq' FlattenEnv a
env Int
c Inlines
is =
    (forall a. FlattenState a -> Int
fsNameIndex FlattenState a
finalState, forall a. FlattenState a -> Seq (Seq (FlattenedValue a))
fsCompletedLines FlattenState a
finalState)
    where
        finalState :: FlattenState a
finalState = forall s a. State s a -> s -> s
execState State (FlattenState a) ()
stBody forall {a}. FlattenState a
initialState
        initialState :: FlattenState a
initialState = FlattenState { fsCompletedLines :: Seq (Seq (FlattenedValue a))
fsCompletedLines = forall a. Monoid a => a
mempty
                                    , fsCurLine :: Seq (FlattenedValue a)
fsCurLine = forall a. Monoid a => a
mempty
                                    , fsNameIndex :: Int
fsNameIndex = Int
c
                                    }
        stBody :: State (FlattenState a) ()
stBody = forall r (m :: * -> *) a. ReaderT r m a -> r -> m a
runReaderT ReaderT (FlattenEnv a) (State (FlattenState a)) ()
body FlattenEnv a
env
        body :: ReaderT (FlattenEnv a) (State (FlattenState a)) ()
body = do
            forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines Inlines
is
            forall a. FlattenM a ()
pushFLine

flattenInlines :: SemEq a => Inlines -> FlattenM a ()
flattenInlines :: forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines Inlines
is = do
    Seq (Maybe (Int -> Maybe a), Inline)
pairs <- forall {a}.
ReaderT
  (FlattenEnv a)
  (State (FlattenState a))
  (Seq (Maybe (Int -> Maybe a), Inline))
nameInlinePairs
    forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
(a -> m b) -> t a -> m ()
mapM_ forall {a}.
SemEq a =>
(Maybe (Int -> Maybe a), Inline) -> FlattenM a ()
wrapFlatten Seq (Maybe (Int -> Maybe a), Inline)
pairs
    where
        wrapFlatten :: (Maybe (Int -> Maybe a), Inline) -> FlattenM a ()
wrapFlatten (Maybe (Int -> Maybe a)
nameFunc, Inline
i) = forall a. Maybe (Int -> Maybe a) -> FlattenM a () -> FlattenM a ()
withNameFunc Maybe (Int -> Maybe a)
nameFunc forall a b. (a -> b) -> a -> b
$ forall a. SemEq a => Inline -> FlattenM a ()
flatten Inline
i

        -- For each inline, prior to flattening it, obtain the resource
        -- name (if any) that should be assigned to each flattened
        -- fragment of the inline.
        nameInlinePairs :: ReaderT
  (FlattenEnv a)
  (State (FlattenState a))
  (Seq (Maybe (Int -> Maybe a), Inline))
nameInlinePairs = forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
t a -> (a -> m b) -> m (t b)
forM (Inlines -> Seq Inline
unInlines Inlines
is) forall a b. (a -> b) -> a -> b
$ \Inline
i -> do
            Maybe (Int -> Maybe a)
nameFunc <- forall a. Inline -> FlattenM a (Maybe (Int -> Maybe a))
nameGenWrapper Inline
i
            forall (m :: * -> *) a. Monad m => a -> m a
return (Maybe (Int -> Maybe a)
nameFunc, Inline
i)

        -- Determine whether the name generation function will produce
        -- a name for this inline. If it does (using a fake sequence
        -- number) then return a new name generation function to use for
        -- all flattened fragments of this inline.
        nameGenWrapper :: Inline -> FlattenM a (Maybe (Int -> Maybe a))
        nameGenWrapper :: forall a. Inline -> FlattenM a (Maybe (Int -> Maybe a))
nameGenWrapper Inline
i = do
            Int
c <- forall s (m :: * -> *) a. MonadState s m => (s -> a) -> m a
gets forall a. FlattenState a -> Int
fsNameIndex
            Maybe (Int -> Inline -> Maybe a)
nameGen <- forall r (m :: * -> *) a. MonadReader r m => (r -> a) -> m a
asks forall a. FlattenEnv a -> Maybe (Int -> Inline -> Maybe a)
flattenNameGen
            forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ case Maybe (Int -> Inline -> Maybe a)
nameGen of
                Maybe (Int -> Inline -> Maybe a)
Nothing -> forall a. Maybe a
Nothing
                Just Int -> Inline -> Maybe a
f -> if forall a. Maybe a -> Bool
isJust (Int -> Inline -> Maybe a
f Int
c Inline
i) then forall a. a -> Maybe a
Just (forall a b c. (a -> b -> c) -> b -> a -> c
flip Int -> Inline -> Maybe a
f Inline
i) else forall a. Maybe a
Nothing

withNameFunc :: Maybe (Int -> Maybe a) -> FlattenM a () -> FlattenM a ()
withNameFunc :: forall a. Maybe (Int -> Maybe a) -> FlattenM a () -> FlattenM a ()
withNameFunc f :: Maybe (Int -> Maybe a)
f@(Just Int -> Maybe a
_) = forall r' r (m :: * -> *) a.
(r' -> r) -> ReaderT r m a -> ReaderT r' m a
withReaderT (\FlattenEnv a
e -> FlattenEnv a
e { flattenNameFunc :: Maybe (Int -> Maybe a)
flattenNameFunc = Maybe (Int -> Maybe a)
f })
withNameFunc Maybe (Int -> Maybe a)
Nothing = forall a. a -> a
id

withInlineStyle :: InlineStyle -> FlattenM a () -> FlattenM a ()
withInlineStyle :: forall a. InlineStyle -> FlattenM a () -> FlattenM a ()
withInlineStyle InlineStyle
s =
    forall r' r (m :: * -> *) a.
(r' -> r) -> ReaderT r m a -> ReaderT r' m a
withReaderT (\FlattenEnv a
e -> FlattenEnv a
e { flattenStyles :: [InlineStyle]
flattenStyles = forall a. Eq a => [a] -> [a]
nub (InlineStyle
s forall a. a -> [a] -> [a]
: forall a. FlattenEnv a -> [InlineStyle]
flattenStyles FlattenEnv a
e) })

withHyperlink :: URL -> FlattenM a () -> FlattenM a ()
withHyperlink :: forall a. URL -> FlattenM a () -> FlattenM a ()
withHyperlink URL
u = forall r' r (m :: * -> *) a.
(r' -> r) -> ReaderT r m a -> ReaderT r' m a
withReaderT (\FlattenEnv a
e -> FlattenEnv a
e { flattenURL :: Maybe URL
flattenURL = forall a. a -> Maybe a
Just URL
u })

-- | Push a FlattenedContent value onto the current line.
pushFC :: SemEq a => FlattenedContent -> FlattenM a ()
pushFC :: forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC FlattenedContent
v = do
    FlattenEnv a
env <- forall r (m :: * -> *). MonadReader r m => m r
ask
    Maybe a
name <- forall a. FlattenM a (Maybe a)
getNextName
    let styles :: [InlineStyle]
styles = forall a. FlattenEnv a -> [InlineStyle]
flattenStyles FlattenEnv a
env
        mUrl :: Maybe URL
mUrl = forall a. FlattenEnv a -> Maybe URL
flattenURL FlattenEnv a
env
        fi :: FlattenedInline a
fi = FlattenedInline { fiValue :: FlattenedContent
fiValue = FlattenedContent
v
                             , fiStyles :: [InlineStyle]
fiStyles = [InlineStyle]
styles
                             , fiURL :: Maybe URL
fiURL = Maybe URL
mUrl
                             , fiName :: Maybe a
fiName = Maybe a
name
                             }
    forall a. SemEq a => FlattenedValue a -> FlattenM a ()
pushFV forall a b. (a -> b) -> a -> b
$ forall a. FlattenedInline a -> FlattenedValue a
SingleInline FlattenedInline a
fi

getNextName :: FlattenM a (Maybe a)
getNextName :: forall a. FlattenM a (Maybe a)
getNextName = do
    Maybe (Int -> Maybe a)
nameGen <- forall r (m :: * -> *) a. MonadReader r m => (r -> a) -> m a
asks forall a. FlattenEnv a -> Maybe (Int -> Maybe a)
flattenNameFunc
    case Maybe (Int -> Maybe a)
nameGen of
        Maybe (Int -> Maybe a)
Nothing -> forall (m :: * -> *) a. Monad m => a -> m a
return forall a. Maybe a
Nothing
        Just Int -> Maybe a
f -> Int -> Maybe a
f forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> forall a. FlattenM a Int
getNextNameIndex

getNextNameIndex :: FlattenM a Int
getNextNameIndex :: forall a. FlattenM a Int
getNextNameIndex = do
    Int
c <- forall s (m :: * -> *) a. MonadState s m => (s -> a) -> m a
gets forall a. FlattenState a -> Int
fsNameIndex
    forall s (m :: * -> *). MonadState s m => (s -> s) -> m ()
modify ( \FlattenState a
s -> FlattenState a
s { fsNameIndex :: Int
fsNameIndex = Int
c forall a. Num a => a -> a -> a
+ Int
1} )
    forall (m :: * -> *) a. Monad m => a -> m a
return Int
c

setNextNameIndex :: Int -> FlattenM a ()
setNextNameIndex :: forall a. Int -> FlattenM a ()
setNextNameIndex Int
i = forall s (m :: * -> *). MonadState s m => (s -> s) -> m ()
modify ( \FlattenState a
s -> FlattenState a
s { fsNameIndex :: Int
fsNameIndex = Int
i } )

-- | Push a FlattenedValue onto the current line.
pushFV :: SemEq a => FlattenedValue a -> FlattenM a ()
pushFV :: forall a. SemEq a => FlattenedValue a -> FlattenM a ()
pushFV FlattenedValue a
fv = forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift forall a b. (a -> b) -> a -> b
$ forall s (m :: * -> *). MonadState s m => (s -> s) -> m ()
modify forall a b. (a -> b) -> a -> b
$ \FlattenState a
s -> FlattenState a
s { fsCurLine :: Seq (FlattenedValue a)
fsCurLine = forall a.
SemEq a =>
FlattenedValue a
-> Seq (FlattenedValue a) -> Seq (FlattenedValue a)
appendFV FlattenedValue a
fv (forall a. FlattenState a -> Seq (FlattenedValue a)
fsCurLine FlattenState a
s) }

-- | Append the value to the sequence.
--
-- If the both the value to append AND the sequence's last value are
-- both text nodes, AND if those nodes both have the same style and URL
-- metadata, then merge them into one text node. This keeps adjacent
-- non-whitespace text together as one logical token (e.g. "(foo" rather
-- than "(" followed by "foo") to avoid undesirable line break points in
-- the wrapping process.
appendFV :: SemEq a => FlattenedValue a -> Seq (FlattenedValue a) -> Seq (FlattenedValue a)
appendFV :: forall a.
SemEq a =>
FlattenedValue a
-> Seq (FlattenedValue a) -> Seq (FlattenedValue a)
appendFV FlattenedValue a
v Seq (FlattenedValue a)
line =
    case (forall a. Seq a -> ViewR a
Seq.viewr Seq (FlattenedValue a)
line, FlattenedValue a
v) of
        (Seq (FlattenedValue a)
h :> SingleInline FlattenedInline a
a, SingleInline FlattenedInline a
b) ->
            case (forall a. FlattenedInline a -> FlattenedContent
fiValue FlattenedInline a
a, forall a. FlattenedInline a -> FlattenedContent
fiValue FlattenedInline a
b) of
                (FText Text
aT, FText Text
bT) ->
                    if forall a. FlattenedInline a -> [InlineStyle]
fiStyles FlattenedInline a
a forall a. Eq a => a -> a -> Bool
== forall a. FlattenedInline a -> [InlineStyle]
fiStyles FlattenedInline a
b Bool -> Bool -> Bool
&& forall a. FlattenedInline a -> Maybe URL
fiURL FlattenedInline a
a forall a. Eq a => a -> a -> Bool
== forall a. FlattenedInline a -> Maybe URL
fiURL FlattenedInline a
b Bool -> Bool -> Bool
&& forall a. FlattenedInline a -> Maybe a
fiName FlattenedInline a
a forall a. SemEq a => a -> a -> Bool
`semeq` forall a. FlattenedInline a -> Maybe a
fiName FlattenedInline a
b
                    then Seq (FlattenedValue a)
h forall a. Seq a -> a -> Seq a
|> forall a. FlattenedInline a -> FlattenedValue a
SingleInline (forall a.
FlattenedContent
-> [InlineStyle] -> Maybe URL -> Maybe a -> FlattenedInline a
FlattenedInline (Text -> FlattenedContent
FText forall a b. (a -> b) -> a -> b
$ Text
aT forall a. Semigroup a => a -> a -> a
<> Text
bT)
                                                            (forall a. FlattenedInline a -> [InlineStyle]
fiStyles FlattenedInline a
a)
                                                            (forall a. FlattenedInline a -> Maybe URL
fiURL FlattenedInline a
a)
                                                            (forall a. Ord a => a -> a -> a
max (forall a. FlattenedInline a -> Maybe a
fiName FlattenedInline a
a) (forall a. FlattenedInline a -> Maybe a
fiName FlattenedInline a
b)))
                    else Seq (FlattenedValue a)
line forall a. Seq a -> a -> Seq a
|> FlattenedValue a
v
                (FlattenedContent, FlattenedContent)
_ -> Seq (FlattenedValue a)
line forall a. Seq a -> a -> Seq a
|> FlattenedValue a
v
        (ViewR (FlattenedValue a), FlattenedValue a)
_ -> Seq (FlattenedValue a)
line forall a. Seq a -> a -> Seq a
|> FlattenedValue a
v

-- | Push the current line onto the finished lines list and start a new
-- line.
pushFLine :: FlattenM a ()
pushFLine :: forall a. FlattenM a ()
pushFLine =
    forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
lift forall a b. (a -> b) -> a -> b
$ forall s (m :: * -> *). MonadState s m => (s -> s) -> m ()
modify forall a b. (a -> b) -> a -> b
$ \FlattenState a
s -> FlattenState a
s { fsCompletedLines :: Seq (Seq (FlattenedValue a))
fsCompletedLines = forall a. FlattenState a -> Seq (Seq (FlattenedValue a))
fsCompletedLines FlattenState a
s forall a. Seq a -> a -> Seq a
|> forall a. FlattenState a -> Seq (FlattenedValue a)
fsCurLine FlattenState a
s
                            , fsCurLine :: Seq (FlattenedValue a)
fsCurLine = forall a. Monoid a => a
mempty
                            }

isKnownUser :: T.Text -> FlattenM a Bool
isKnownUser :: forall a. Text -> FlattenM a Bool
isKnownUser Text
u = do
    HighlightSet
hSet <- forall r (m :: * -> *) a. MonadReader r m => (r -> a) -> m a
asks forall a. FlattenEnv a -> HighlightSet
flattenHighlightSet
    let uSet :: Set Text
uSet = HighlightSet -> Set Text
hUserSet HighlightSet
hSet
    forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ Text
u forall a. Ord a => a -> Set a -> Bool
`Set.member` Set Text
uSet

isKnownChannel :: T.Text -> FlattenM a Bool
isKnownChannel :: forall a. Text -> FlattenM a Bool
isKnownChannel Text
c = do
    HighlightSet
hSet <- forall r (m :: * -> *) a. MonadReader r m => (r -> a) -> m a
asks forall a. FlattenEnv a -> HighlightSet
flattenHighlightSet
    let cSet :: Set Text
cSet = HighlightSet -> Set Text
hChannelSet HighlightSet
hSet
    forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ Text
c forall a. Ord a => a -> Set a -> Bool
`Set.member` Set Text
cSet

flatten :: SemEq a => Inline -> FlattenM a ()
flatten :: forall a. SemEq a => Inline -> FlattenM a ()
flatten Inline
i =
    case Inline
i of
        EUser Text
u -> do
            Bool
known <- forall a. Text -> FlattenM a Bool
isKnownUser Text
u
            if Bool
known then forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC (Text -> FlattenedContent
FUser Text
u)
                     else forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC (Text -> FlattenedContent
FText forall a b. (a -> b) -> a -> b
$ Text -> Text
addUserSigil Text
u)
        EChannel Text
c -> do
            Bool
known <- forall a. Text -> FlattenM a Bool
isKnownChannel Text
c
            if Bool
known then forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC (Text -> FlattenedContent
FChannel Text
c)
                     else forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC (Text -> FlattenedContent
FText forall a b. (a -> b) -> a -> b
$ Text
normalChannelSigil forall a. Semigroup a => a -> a -> a
<> Text
c)

        ENonBreaking Inlines
is -> do
            FlattenEnv a
env <- forall r (m :: * -> *). MonadReader r m => m r
ask
            Int
ni <- forall a. FlattenM a Int
getNextNameIndex
            let (Int
ni', Seq (Seq (FlattenedValue a))
s) = forall a.
SemEq a =>
FlattenEnv a
-> Int -> Inlines -> (Int, Seq (Seq (FlattenedValue a)))
flattenInlineSeq' FlattenEnv a
env Int
ni Inlines
is
            forall a. SemEq a => FlattenedValue a -> FlattenM a ()
pushFV forall a b. (a -> b) -> a -> b
$ forall a. Seq (Seq (FlattenedValue a)) -> FlattenedValue a
NonBreaking Seq (Seq (FlattenedValue a))
s
            forall a. Int -> FlattenM a ()
setNextNameIndex Int
ni'

        Inline
ESoftBreak                  -> forall a. FlattenM a ()
pushFLine
        Inline
ELineBreak                  -> forall a. FlattenM a ()
pushFLine

        EText Text
t                     -> forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC forall a b. (a -> b) -> a -> b
$ Text -> FlattenedContent
FText Text
t
        Inline
ESpace                      -> forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC FlattenedContent
FSpace
        ERawHtml Text
h                  -> forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC forall a b. (a -> b) -> a -> b
$ Text -> FlattenedContent
FText Text
h
        EEmoji Text
e                    -> forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC forall a b. (a -> b) -> a -> b
$ Text -> FlattenedContent
FEmoji Text
e
        EEditSentinel Bool
r             -> forall a. SemEq a => FlattenedContent -> FlattenM a ()
pushFC forall a b. (a -> b) -> a -> b
$ Bool -> FlattenedContent
FEditSentinel Bool
r

        EEmph Inlines
es                    -> forall a. InlineStyle -> FlattenM a () -> FlattenM a ()
withInlineStyle InlineStyle
Emph forall a b. (a -> b) -> a -> b
$ forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines Inlines
es
        EStrikethrough Inlines
es           -> forall a. InlineStyle -> FlattenM a () -> FlattenM a ()
withInlineStyle InlineStyle
Strikethrough forall a b. (a -> b) -> a -> b
$ forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines Inlines
es
        EStrong Inlines
es                  -> forall a. InlineStyle -> FlattenM a () -> FlattenM a ()
withInlineStyle InlineStyle
Strong forall a b. (a -> b) -> a -> b
$ forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines Inlines
es
        ECode Inlines
es                    -> forall a. InlineStyle -> FlattenM a () -> FlattenM a ()
withInlineStyle InlineStyle
Code forall a b. (a -> b) -> a -> b
$ forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines Inlines
es

        EPermalink TeamURLName
_ PostId
_ Maybe Inlines
mLabel ->
            let label' :: Inlines
label' = forall a. a -> Maybe a -> a
fromMaybe (Seq Inline -> Inlines
Inlines forall a b. (a -> b) -> a -> b
$ forall a. [a] -> Seq a
Seq.fromList [Text -> Inline
EText Text
"post", Inline
ESpace, Text -> Inline
EText Text
"link"])
                                   Maybe Inlines
mLabel
            in forall a. InlineStyle -> FlattenM a () -> FlattenM a ()
withInlineStyle InlineStyle
Permalink forall a b. (a -> b) -> a -> b
$ forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines forall a b. (a -> b) -> a -> b
$ Inlines -> Inlines
decorateLinkLabel Inlines
label'

        EHyperlink URL
u label :: Inlines
label@(Inlines Seq Inline
ls) ->
            let label' :: Inlines
label' = if forall a. Seq a -> Bool
Seq.null Seq Inline
ls
                         then Seq Inline -> Inlines
Inlines forall a b. (a -> b) -> a -> b
$ forall a. a -> Seq a
Seq.singleton forall a b. (a -> b) -> a -> b
$ Text -> Inline
EText forall a b. (a -> b) -> a -> b
$ URL -> Text
unURL URL
u
                         else Inlines
label
            in forall a. URL -> FlattenM a () -> FlattenM a ()
withHyperlink URL
u forall a b. (a -> b) -> a -> b
$ forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines forall a b. (a -> b) -> a -> b
$ Inlines -> Inlines
decorateLinkLabel Inlines
label'

        EImage URL
u label :: Inlines
label@(Inlines Seq Inline
ls) ->
            let label' :: Inlines
label' = if forall a. Seq a -> Bool
Seq.null Seq Inline
ls
                         then Seq Inline -> Inlines
Inlines forall a b. (a -> b) -> a -> b
$ forall a. a -> Seq a
Seq.singleton forall a b. (a -> b) -> a -> b
$ Text -> Inline
EText forall a b. (a -> b) -> a -> b
$ URL -> Text
unURL URL
u
                         else Inlines
label
            in forall a. URL -> FlattenM a () -> FlattenM a ()
withHyperlink URL
u forall a b. (a -> b) -> a -> b
$ forall a. SemEq a => Inlines -> FlattenM a ()
flattenInlines forall a b. (a -> b) -> a -> b
$ Inlines -> Inlines
decorateLinkLabel Inlines
label'

linkOpenBracket :: Inline
linkOpenBracket :: Inline
linkOpenBracket = Text -> Inline
EText Text
"<"

linkCloseBracket :: Inline
linkCloseBracket :: Inline
linkCloseBracket = Text -> Inline
EText Text
">"

addOpenBracket :: Inlines -> Inlines
addOpenBracket :: Inlines -> Inlines
addOpenBracket (Inlines Seq Inline
l) =
    case forall a. Seq a -> ViewL a
Seq.viewl Seq Inline
l of
        ViewL Inline
EmptyL -> Seq Inline -> Inlines
Inlines Seq Inline
l
        Inline
h :< Seq Inline
t ->
            let h' :: Inline
h' = Inlines -> Inline
ENonBreaking forall a b. (a -> b) -> a -> b
$ Seq Inline -> Inlines
Inlines forall a b. (a -> b) -> a -> b
$ forall a. [a] -> Seq a
Seq.fromList [Inline
linkOpenBracket, Inline
h]
            in Seq Inline -> Inlines
Inlines forall a b. (a -> b) -> a -> b
$ Inline
h' forall a. a -> Seq a -> Seq a
<| Seq Inline
t

addCloseBracket :: Inlines -> Inlines
addCloseBracket :: Inlines -> Inlines
addCloseBracket (Inlines Seq Inline
l) =
    case forall a. Seq a -> ViewR a
Seq.viewr Seq Inline
l of
        ViewR Inline
EmptyR -> Seq Inline -> Inlines
Inlines Seq Inline
l
        Seq Inline
h :> Inline
t ->
            let t' :: Inline
t' = Inlines -> Inline
ENonBreaking forall a b. (a -> b) -> a -> b
$ Seq Inline -> Inlines
Inlines forall a b. (a -> b) -> a -> b
$ forall a. [a] -> Seq a
Seq.fromList [Inline
t, Inline
linkCloseBracket]
            in Seq Inline -> Inlines
Inlines forall a b. (a -> b) -> a -> b
$ Seq Inline
h forall a. Seq a -> a -> Seq a
|> Inline
t'

decorateLinkLabel :: Inlines -> Inlines
decorateLinkLabel :: Inlines -> Inlines
decorateLinkLabel = Inlines -> Inlines
addOpenBracket forall b c a. (b -> c) -> (a -> b) -> a -> c
.  Inlines -> Inlines
addCloseBracket