{-# LANGUAGE LambdaCase        #-}
{-# LANGUAGE OverloadedStrings #-}
{- |
   Module      : Text.Pandoc.Lua.Module.MediaBag
   Copyright   : Copyright © 2017-2023 Albert Krewinkel
   License     : GNU GPL, version 2 or above
   Maintainer  : Albert Krewinkel <tarleb+pandoc@moltkeplatz.de>

The Lua module @pandoc.mediabag@.
-}
module Text.Pandoc.Lua.Module.MediaBag
  ( documentedModule
  ) where

import Prelude hiding (lookup)
import Data.Maybe (fromMaybe)
import Data.Version (makeVersion)
import HsLua ( LuaE, DocumentedFunction, Module (..)
             , (<#>), (###), (=#>), (=?>), (#?), defun, functionResult
             , opt, parameter, since, stringParam, textParam)
import Text.Pandoc.Class ( CommonState (..), fetchItem, fillMediaBag
                         , getMediaBag, modifyCommonState, setMediaBag)
import Text.Pandoc.Class.IO (writeMedia)
import Text.Pandoc.Error (PandocError)
import Text.Pandoc.Lua.Marshal.Pandoc (peekPandoc, pushPandoc)
import Text.Pandoc.Lua.Marshal.List (pushPandocList)
import Text.Pandoc.Lua.Orphans ()
import Text.Pandoc.Lua.PandocLua (unPandocLua)
import Text.Pandoc.MIME (MimeType)

import qualified Data.ByteString.Lazy as BL
import qualified Data.Text as T
import qualified HsLua as Lua
import qualified Text.Pandoc.MediaBag as MB

--
-- MediaBag submodule
--
documentedModule :: Module PandocError
documentedModule :: Module PandocError
documentedModule = Module
  { moduleName :: Name
moduleName = Name
"pandoc.mediabag"
  , moduleDescription :: Text
moduleDescription = Text
"mediabag access"
  , moduleFields :: [Field PandocError]
moduleFields = []
  , moduleFunctions :: [DocumentedFunction PandocError]
moduleFunctions =
      [ DocumentedFunction PandocError
delete
      , DocumentedFunction PandocError
empty
      , DocumentedFunction PandocError
fetch
      , DocumentedFunction PandocError
fill
      , DocumentedFunction PandocError
insert
      , DocumentedFunction PandocError
items
      , DocumentedFunction PandocError
list
      , DocumentedFunction PandocError
lookup
      , DocumentedFunction PandocError
write
      ]
  , moduleOperations :: [(Operation, DocumentedFunction PandocError)]
moduleOperations = []
  , moduleTypeInitializers :: [LuaE PandocError Name]
moduleTypeInitializers = []
  }

-- | Delete a single item from the media bag.
delete :: DocumentedFunction PandocError
delete :: DocumentedFunction PandocError
delete = Name
-> (String -> LuaE PandocError ())
-> HsFnPrecursor PandocError (String -> LuaE PandocError ())
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"delete"
  ### (\fp -> unPandocLua $ modifyCommonState
              (\st -> st { stMediaBag = MB.deleteMedia fp (stMediaBag st) }))
  HsFnPrecursor PandocError (String -> LuaE PandocError ())
-> Parameter PandocError String
-> HsFnPrecursor PandocError (LuaE PandocError ())
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Text -> Text -> Parameter PandocError String
forall e. Text -> Text -> Parameter e String
stringParam Text
"filepath" Text
"filename of item to delete"
  HsFnPrecursor PandocError (LuaE PandocError ())
-> FunctionResults PandocError () -> DocumentedFunction PandocError
forall e a.
HsFnPrecursor e (LuaE e a)
-> FunctionResults e a -> DocumentedFunction e
=#> []


-- | Delete all items from the media bag.
empty :: DocumentedFunction PandocError
empty :: DocumentedFunction PandocError
empty = Name
-> LuaE PandocError ()
-> HsFnPrecursor PandocError (LuaE PandocError ())
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"empty"
  ### unPandocLua (modifyCommonState (\st -> st { stMediaBag = mempty }))
  HsFnPrecursor PandocError (LuaE PandocError ())
-> FunctionResults PandocError () -> DocumentedFunction PandocError
forall e a.
HsFnPrecursor e (LuaE e a)
-> FunctionResults e a -> DocumentedFunction e
=#> []

-- | Fill the mediabag with all images in the document that aren't
-- present yet.
fill :: DocumentedFunction PandocError
fill :: DocumentedFunction PandocError
fill = Name
-> (Pandoc -> LuaE PandocError Pandoc)
-> HsFnPrecursor PandocError (Pandoc -> LuaE PandocError Pandoc)
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"fill"
  ### unPandocLua . fillMediaBag
  HsFnPrecursor PandocError (Pandoc -> LuaE PandocError Pandoc)
-> Parameter PandocError Pandoc
-> HsFnPrecursor PandocError (LuaE PandocError Pandoc)
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Peeker PandocError Pandoc
-> TypeSpec -> Text -> Text -> Parameter PandocError Pandoc
forall e a. Peeker e a -> TypeSpec -> Text -> Text -> Parameter e a
parameter Peeker PandocError Pandoc
forall e. LuaError e => Peeker e Pandoc
peekPandoc TypeSpec
"Pandoc" Text
"doc"
        Text
"document from which to fill the mediabag"
  HsFnPrecursor PandocError (LuaE PandocError Pandoc)
-> FunctionResults PandocError Pandoc
-> DocumentedFunction PandocError
forall e a.
HsFnPrecursor e (LuaE e a)
-> FunctionResults e a -> DocumentedFunction e
=#> Pusher PandocError Pandoc
-> TypeSpec -> Text -> FunctionResults PandocError Pandoc
forall e a. Pusher e a -> TypeSpec -> Text -> FunctionResults e a
functionResult Pusher PandocError Pandoc
forall e. LuaError e => Pusher e Pandoc
pushPandoc TypeSpec
"Pandoc" Text
"modified document"
  #? ("Fills the mediabag with the images in the given document.\n" <>
      "An image that cannot be retrieved will be replaced with a Span\n" <>
      "of class \"image\" that contains the image description.\n" <>
      "" <>
      "Images for which the mediabag already contains an item will\n" <>
      "not be processed again.")

-- | Insert a new item into the media bag.
insert :: DocumentedFunction PandocError
insert :: DocumentedFunction PandocError
insert = Name
-> (String
    -> Maybe Text -> ByteString -> LuaE PandocError NumResults)
-> HsFnPrecursor
     PandocError
     (String -> Maybe Text -> ByteString -> LuaE PandocError NumResults)
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"insert"
  ### (\fp mmime contents -> unPandocLua $ do
          mb <- getMediaBag
          setMediaBag $ MB.insertMedia fp mmime contents mb
          return (Lua.NumResults 0))
  HsFnPrecursor
  PandocError
  (String -> Maybe Text -> ByteString -> LuaE PandocError NumResults)
-> Parameter PandocError String
-> HsFnPrecursor
     PandocError
     (Maybe Text -> ByteString -> LuaE PandocError NumResults)
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Text -> Text -> Parameter PandocError String
forall e. Text -> Text -> Parameter e String
stringParam Text
"filepath" Text
"item file path"
  HsFnPrecursor
  PandocError
  (Maybe Text -> ByteString -> LuaE PandocError NumResults)
-> Parameter PandocError (Maybe Text)
-> HsFnPrecursor
     PandocError (ByteString -> LuaE PandocError NumResults)
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Parameter PandocError Text -> Parameter PandocError (Maybe Text)
forall e a. Parameter e a -> Parameter e (Maybe a)
opt (Text -> Text -> Parameter PandocError Text
forall e. Text -> Text -> Parameter e Text
textParam Text
"mimetype" Text
"the item's MIME type")
  HsFnPrecursor
  PandocError (ByteString -> LuaE PandocError NumResults)
-> Parameter PandocError ByteString
-> HsFnPrecursor PandocError (LuaE PandocError NumResults)
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Peeker PandocError ByteString
-> TypeSpec -> Text -> Text -> Parameter PandocError ByteString
forall e a. Peeker e a -> TypeSpec -> Text -> Text -> Parameter e a
parameter Peeker PandocError ByteString
forall e. Peeker e ByteString
Lua.peekLazyByteString TypeSpec
"string" Text
"contents" Text
"binary contents"
  HsFnPrecursor PandocError (LuaE PandocError NumResults)
-> FunctionResults PandocError NumResults
-> DocumentedFunction PandocError
forall e a.
HsFnPrecursor e (LuaE e a)
-> FunctionResults e a -> DocumentedFunction e
=#> []

-- | Returns iterator values to be used with a Lua @for@ loop.
items :: DocumentedFunction PandocError
items :: DocumentedFunction PandocError
items = Name
-> LuaE PandocError NumResults
-> HsFnPrecursor PandocError (LuaE PandocError NumResults)
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"items"
  ### (do
          mb <-unPandocLua getMediaBag
          let pushItem (fp, mimetype, contents) = do
                Lua.pushString fp
                Lua.pushText mimetype
                Lua.pushByteString $ BL.toStrict contents
                return (Lua.NumResults 3)
          Lua.pushIterator pushItem (MB.mediaItems mb))
  HsFnPrecursor PandocError (LuaE PandocError NumResults)
-> Text -> DocumentedFunction PandocError
forall e.
HsFnPrecursor e (LuaE e NumResults) -> Text -> DocumentedFunction e
=?> Text
"Iterator triple"

-- | Function to lookup a value in the mediabag.
lookup :: DocumentedFunction PandocError
lookup :: DocumentedFunction PandocError
lookup = Name
-> (String -> LuaE PandocError NumResults)
-> HsFnPrecursor
     PandocError (String -> LuaE PandocError NumResults)
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"lookup"
  ### (\fp -> unPandocLua (MB.lookupMedia fp <$> getMediaBag) >>= \case
          Nothing   -> 1 <$ Lua.pushnil
          Just item -> 2 <$ do
            Lua.pushText $ MB.mediaMimeType item
            Lua.pushLazyByteString $ MB.mediaContents item)
  HsFnPrecursor PandocError (String -> LuaE PandocError NumResults)
-> Parameter PandocError String
-> HsFnPrecursor PandocError (LuaE PandocError NumResults)
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Text -> Text -> Parameter PandocError String
forall e. Text -> Text -> Parameter e String
stringParam Text
"filepath" Text
"path of item to lookup"
  HsFnPrecursor PandocError (LuaE PandocError NumResults)
-> Text -> DocumentedFunction PandocError
forall e.
HsFnPrecursor e (LuaE e NumResults) -> Text -> DocumentedFunction e
=?> Text
"MIME type and contents"

-- | Function listing all mediabag items.
list :: DocumentedFunction PandocError
list :: DocumentedFunction PandocError
list = Name
-> LuaE PandocError [(String, Text, Int)]
-> HsFnPrecursor
     PandocError (LuaE PandocError [(String, Text, Int)])
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"list"
  ### (unPandocLua (MB.mediaDirectory <$> getMediaBag))
  HsFnPrecursor PandocError (LuaE PandocError [(String, Text, Int)])
-> FunctionResults PandocError [(String, Text, Int)]
-> DocumentedFunction PandocError
forall e a.
HsFnPrecursor e (LuaE e a)
-> FunctionResults e a -> DocumentedFunction e
=#> Pusher PandocError [(String, Text, Int)]
-> TypeSpec
-> Text
-> FunctionResults PandocError [(String, Text, Int)]
forall e a. Pusher e a -> TypeSpec -> Text -> FunctionResults e a
functionResult (Pusher PandocError (String, Text, Int)
-> Pusher PandocError [(String, Text, Int)]
forall e a. LuaError e => Pusher e a -> Pusher e [a]
pushPandocList Pusher PandocError (String, Text, Int)
pushEntry) TypeSpec
"table" Text
"list of entry triples"
 where
  pushEntry :: (FilePath, MimeType, Int) -> LuaE PandocError ()
  pushEntry :: Pusher PandocError (String, Text, Int)
pushEntry (String
fp, Text
mimeType, Int
contentLength) = do
    LuaE PandocError ()
forall e. LuaE e ()
Lua.newtable
    Name -> LuaE PandocError ()
forall e. Name -> LuaE e ()
Lua.pushName Name
"path"   LuaE PandocError () -> LuaE PandocError () -> LuaE PandocError ()
forall a b.
LuaE PandocError a -> LuaE PandocError b -> LuaE PandocError b
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
*> String -> LuaE PandocError ()
forall e. String -> LuaE e ()
Lua.pushString String
fp              LuaE PandocError () -> LuaE PandocError () -> LuaE PandocError ()
forall a b.
LuaE PandocError a -> LuaE PandocError b -> LuaE PandocError b
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
*> StackIndex -> LuaE PandocError ()
forall e. LuaError e => StackIndex -> LuaE e ()
Lua.rawset (-StackIndex
3)
    Name -> LuaE PandocError ()
forall e. Name -> LuaE e ()
Lua.pushName Name
"type"   LuaE PandocError () -> LuaE PandocError () -> LuaE PandocError ()
forall a b.
LuaE PandocError a -> LuaE PandocError b -> LuaE PandocError b
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
*> Pusher PandocError Text
forall e. Pusher e Text
Lua.pushText Text
mimeType          LuaE PandocError () -> LuaE PandocError () -> LuaE PandocError ()
forall a b.
LuaE PandocError a -> LuaE PandocError b -> LuaE PandocError b
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
*> StackIndex -> LuaE PandocError ()
forall e. LuaError e => StackIndex -> LuaE e ()
Lua.rawset (-StackIndex
3)
    Name -> LuaE PandocError ()
forall e. Name -> LuaE e ()
Lua.pushName Name
"length" LuaE PandocError () -> LuaE PandocError () -> LuaE PandocError ()
forall a b.
LuaE PandocError a -> LuaE PandocError b -> LuaE PandocError b
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
*> Int -> LuaE PandocError ()
forall a e. (Integral a, Show a) => a -> LuaE e ()
Lua.pushIntegral Int
contentLength LuaE PandocError () -> LuaE PandocError () -> LuaE PandocError ()
forall a b.
LuaE PandocError a -> LuaE PandocError b -> LuaE PandocError b
forall (f :: * -> *) a b. Applicative f => f a -> f b -> f b
*> StackIndex -> LuaE PandocError ()
forall e. LuaError e => StackIndex -> LuaE e ()
Lua.rawset (-StackIndex
3)

-- | Lua function to retrieve a new item.
fetch :: DocumentedFunction PandocError
fetch :: DocumentedFunction PandocError
fetch = Name
-> (Text -> LuaE PandocError NumResults)
-> HsFnPrecursor PandocError (Text -> LuaE PandocError NumResults)
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"fetch"
  ### (\src -> do
          (bs, mimeType) <- unPandocLua $ fetchItem src
          Lua.pushText $ fromMaybe "" mimeType
          Lua.pushByteString bs
          return 2)
  HsFnPrecursor PandocError (Text -> LuaE PandocError NumResults)
-> Parameter PandocError Text
-> HsFnPrecursor PandocError (LuaE PandocError NumResults)
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Text -> Text -> Parameter PandocError Text
forall e. Text -> Text -> Parameter e Text
textParam Text
"src" Text
"URI to fetch"
  HsFnPrecursor PandocError (LuaE PandocError NumResults)
-> Text -> DocumentedFunction PandocError
forall e.
HsFnPrecursor e (LuaE e NumResults) -> Text -> DocumentedFunction e
=?> Text
"Returns two string values: the fetched contents and the mimetype."

-- | Extract the mediabag or just a single entry.
write :: DocumentedFunction PandocError
write :: DocumentedFunction PandocError
write = Name
-> (String -> Maybe String -> LuaE PandocError ())
-> HsFnPrecursor
     PandocError (String -> Maybe String -> LuaE PandocError ())
forall a e. Name -> a -> HsFnPrecursor e a
defun Name
"write"
  ### (\dir mfp -> do
          mb <- unPandocLua getMediaBag
          case mfp of
            Nothing -> unPandocLua $ mapM_ (writeMedia dir) (MB.mediaItems mb)
            Just fp -> do
              case MB.lookupMedia fp mb of
                Nothing   -> Lua.failLua ("Resource not in mediabag: " <> fp)
                Just item -> unPandocLua $ do
                  let triple = ( MB.mediaPath item
                               , MB.mediaMimeType item
                               , MB.mediaContents item
                               )
                  writeMedia dir triple)
  HsFnPrecursor
  PandocError (String -> Maybe String -> LuaE PandocError ())
-> Parameter PandocError String
-> HsFnPrecursor PandocError (Maybe String -> LuaE PandocError ())
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Text -> Text -> Parameter PandocError String
forall e. Text -> Text -> Parameter e String
stringParam Text
"dir" Text
"path of the target directory"
  HsFnPrecursor PandocError (Maybe String -> LuaE PandocError ())
-> Parameter PandocError (Maybe String)
-> HsFnPrecursor PandocError (LuaE PandocError ())
forall e a b.
HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b
<#> Parameter PandocError String
-> Parameter PandocError (Maybe String)
forall e a. Parameter e a -> Parameter e (Maybe a)
opt (Text -> Text -> Parameter PandocError String
forall e. Text -> Text -> Parameter e String
stringParam Text
"fp" Text
"canonical name (relative path) of resource")
  HsFnPrecursor PandocError (LuaE PandocError ())
-> FunctionResults PandocError () -> DocumentedFunction PandocError
forall e a.
HsFnPrecursor e (LuaE e a)
-> FunctionResults e a -> DocumentedFunction e
=#> []
  #? T.unlines
     [ "Writes the contents of  mediabag to the given target directory. If"
     , "`fp` is given, then only the resource with the given name will be"
     , "extracted. Omitting that parameter means that the whole mediabag"
     , "gets extracted. An error is thrown if `fp` is given but cannot be"
     , "found in the mediabag."
     ]
  DocumentedFunction PandocError
-> Version -> DocumentedFunction PandocError
forall e. DocumentedFunction e -> Version -> DocumentedFunction e
`since` [Int] -> Version
makeVersion [Int
3, Int
0]