aboutsummaryrefslogtreecommitdiff
path: root/compiler/src/Processors.hs
blob: 16837a65178295802a0cc2fdb9177e5d7f26053d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
-- ldgallery - A static generator which turns a collection of tagged
--             pictures into a searchable web gallery.
--
-- Copyright (C) 2019-2020  Pacien TRAN-GIRARD
--
-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU Affero General Public License as
-- published by the Free Software Foundation, either version 3 of the
-- License, or (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-- GNU Affero General Public License for more details.
--
-- You should have received a copy of the GNU Affero General Public License
-- along with this program.  If not, see <https://www.gnu.org/licenses/>.

module Processors
  ( Resolution(..)
  , ItemFileProcessor, itemFileProcessor
  , ThumbnailFileProcessor, thumbnailFileProcessor
  , skipCached, withCached
  ) where


import Control.Exception (Exception)
import Data.Function ((&))
import Data.Char (toLower)
import Data.List (break)

import System.Directory hiding (copyFile)
import qualified System.Directory
import System.FilePath

import System.Process (callProcess, readProcess)

import Resource
  ( ItemProcessor, ThumbnailProcessor
  , GalleryItemProps(..), Resolution(..), Resource(..), Thumbnail(..) )

import Files


data ProcessingException = ProcessingException FilePath String deriving Show
instance Exception ProcessingException


-- TODO: handle video, music, text...
data Format = PictureFormat | Unknown

formatFromPath :: Path -> Format
formatFromPath =
  maybe Unknown fromExt
  . fmap (map toLower)
  . fmap takeExtension
  . fileName
  where
    fromExt :: String -> Format
    fromExt ext = case ext of
      ".bmp" -> PictureFormat
      ".jpg" -> PictureFormat
      ".jpeg" -> PictureFormat
      ".png" -> PictureFormat
      ".tiff" -> PictureFormat
      ".hdr" -> PictureFormat
      ".gif" -> PictureFormat
      _ -> Unknown


type FileProcessor =
     FileName        -- ^ Input path
  -> FileName        -- ^ Output path
  -> IO ()

copyFileProcessor :: FileProcessor
copyFileProcessor inputPath outputPath =
  (putStrLn $ "Copying:\t" ++ outputPath)
  >> ensureParentDir (flip System.Directory.copyFile) outputPath inputPath

resizePictureUpTo :: Resolution -> FileProcessor
resizePictureUpTo maxResolution inputPath outputPath =
  (putStrLn $ "Generating:\t" ++ outputPath)
  >> ensureParentDir (flip resize) outputPath inputPath
  where
    maxSize :: Resolution -> String
    maxSize Resolution{width, height} = show width ++ "x" ++ show height ++ ">"

    resize :: FileName -> FileName -> IO ()
    resize input output = callProcess "magick"
      [ input
      , "-auto-orient"
      , "-resize", maxSize maxResolution
      , output ]


type Cache = FileProcessor -> FileProcessor

skipCached :: Cache
skipCached processor inputPath outputPath =
  removePathForcibly outputPath
  >> processor inputPath outputPath

withCached :: Cache
withCached processor inputPath outputPath =
  do
    isDir <- doesDirectoryExist outputPath
    if isDir then removePathForcibly outputPath else noop

    fileExists <- doesFileExist outputPath
    if fileExists then
      do
        needUpdate <- isOutdated True inputPath outputPath
        if needUpdate then update else skip
    else
      update

  where
    noop = return ()
    update = processor inputPath outputPath
    skip = putStrLn $ "Skipping:\t" ++ outputPath


resourceAt :: FilePath -> Path -> IO Resource
resourceAt fsPath resPath = getModificationTime fsPath >>= return . Resource resPath

getImageResolution :: FilePath -> IO Resolution
getImageResolution fsPath =
  readProcess "identify" ["-format", "%w %h", firstFrame] []
  >>= return . break (== ' ')
  >>= return . \(w, h) -> Resolution (read w) (read h)
  where
    firstFrame = fsPath ++ "[0]"


type ItemFileProcessor =
     FileName        -- ^ Input base path
  -> FileName        -- ^ Output base path
  -> FileName        -- ^ Output class (subdir)
  -> ItemProcessor

itemFileProcessor :: Maybe Resolution -> Cache -> ItemFileProcessor
itemFileProcessor maxResolution cached inputBase outputBase resClass inputRes =
  cached processor inPath outPath
  >> resourceAt outPath relOutPath
  >>= return . props
  where
    relOutPath = resClass /> inputRes
    inPath = localPath $ inputBase /> inputRes
    outPath = localPath $ outputBase /> relOutPath
    (processor, props) = processorFor maxResolution $ formatFromPath inputRes

    processorFor :: Maybe Resolution -> Format -> (FileProcessor, Resource -> GalleryItemProps)
    processorFor (Just maxRes) PictureFormat = (resizePictureUpTo maxRes, Picture)
    processorFor Nothing PictureFormat = (copyFileProcessor, Picture)
    processorFor _ Unknown = (copyFileProcessor, Other) -- TODO: handle video reencoding and others?


type ThumbnailFileProcessor =
     FileName        -- ^ Input base path
  -> FileName        -- ^ Output base path
  -> FileName        -- ^ Output class (subdir)
  -> ThumbnailProcessor

thumbnailFileProcessor :: Resolution -> Cache -> ThumbnailFileProcessor
thumbnailFileProcessor maxRes cached inputBase outputBase resClass inputRes =
  cached <$> processorFor (formatFromPath inputRes)
  & process
  where
    relOutPath = resClass /> inputRes
    inPath = localPath $ inputBase /> inputRes
    outPath = localPath $ outputBase /> relOutPath

    process :: Maybe FileProcessor -> IO (Maybe Thumbnail)
    process Nothing = return Nothing
    process (Just proc) =
      do
        proc inPath outPath
        resource <- resourceAt outPath relOutPath
        resolution <- getImageResolution outPath
        return $ Just $ Thumbnail resource resolution

    processorFor :: Format -> Maybe FileProcessor
    processorFor PictureFormat = Just $ resizePictureUpTo maxRes
    processorFor _ = Nothing