src/image-render.lua

205 lines

1-- image-render.lua

2--

3-- Issue 9-013 (redesign) — renderer side. The augmentation step

4-- (augment-embeddings-with-images.lua) ranks images alongside poems and writes

5-- image-manifest.json. This module lets flat-html-generator DRAW those image

6-- entries: it injects lightweight "pseudo-poem" objects into the poems list so

7-- the existing poem_index lookups find them, and formats an image as a small

8-- box instead of a poem.

9--

10-- Kept separate (and dependency-light) so it can be required from both the main

11-- thread and each effil worker's fresh Lua state, and unit-tested on its own.

13local M = {}

15local manifest_cache = nil -- per-process memoize (worker states each load once)

17-- {{{ function M.load_manifest()

18-- Read image-manifest.json from `path`. Returns the { "poem_index" = record }

19-- map, or an empty table if the file is absent (the feature is optional: no

20-- manifest -> no image entries, poems render exactly as before). Memoized per

21-- process so each worker state parses it at most once.

22function M.load_manifest(path, read_json_fn)

23 if manifest_cache ~= nil then return manifest_cache end

24 local data = read_json_fn(path)

25 manifest_cache = (data and data.images) or {}

26 return manifest_cache

27end

28-- }}}

30-- {{{ local function basename()

31local function basename(path)

32 return (path or ""):match("([^/]+)$") or (path or "")

33end

34-- }}}

36-- {{{ local function media_href()

37-- Where a file lives under output/media/, url-encoded for an href/src.

38-- Art images (path under input/images/<source>/...) KEEP their source + subdir

39-- structure, because their human-given basenames collide (e.g.

40-- my-art/proposed-movement-design.png vs my-art/game-design/proposed-movement-design.png)

41-- and a flat output/media/<basename> would let one silently overwrite the other.

42-- flatten_media_files writes art to the very same <source>/<subpath>, so the two

43-- agree. Mastodon attachments (content-addressed hashes, NOT under input/images/)

44-- keep just the basename -- already unique, and we don't want their 7-level

45-- nesting back. Slashes are preserved; space / ? / # / % are percent-encoded.

46-- Inlined (not required from a lib) on purpose: this module also runs inside

47-- effil worker threads with their own Lua state.

48local function media_href(path)

49 path = path or ""

50 local sub = path:match("input/images/(.+)$") or (path:match("([^/]+)$") or path)

51 return (sub:gsub("[^%w%-%._~/]", function(c)

52 return string.format("%%%02X", string.byte(c))

53 end))

54end

55-- }}}

57-- {{{ local function media_type_for()

58-- Guess a media_type from a filename extension (the manifest stores width/height

59-- but render_attachment_images keys image rendering off "image/...").

60local function media_type_for(filename)

61 local ext = (filename or ""):match("%.([%a%d]+)$")

62 return "image/" .. (ext and ext:lower() or "png")

63end

64-- }}}

66-- {{{ function M.inject_pseudo_poems()

67-- Append one pseudo-poem per manifest image to poems_data.poems so the

68-- renderer's poem_index lookups resolve them. Idempotent: a second call is a

69-- no-op (guarded by a marker on poems_data), so it is safe to call after every

70-- poems.json load. Class 2 (image-only posts) ALREADY exist in poems_data with

71-- their real poem_index -- we only TAG those in place; class 3 (standalone

72-- catalog images, poem_index beyond the poem range) are genuinely new and get

73-- appended.

74function M.inject_pseudo_poems(poems_data, manifest)

75 if not poems_data or not poems_data.poems then return poems_data end

76 if poems_data._images_injected then return poems_data end

77 poems_data._images_injected = true

78 if not manifest then return poems_data end

80 -- Index existing poems so class-2 entries can be tagged in place.

81 local by_index = {}

82 for _, p in ipairs(poems_data.poems) do by_index[p.poem_index] = p end

84 for key, rec in pairs(manifest) do

85 local pidx = rec.poem_index or tonumber(key)

86 if rec.class == 2 then

87 -- Tag the existing image-only post so the formatter draws it as an

88 -- image. Its attachments + content already live in poems_data.

89 local p = by_index[pidx]

90 if p then

91 p.is_image = true

92 p.image_class = 2

93 p.display_title = rec.category and (rec.category .. ": image post") or "image post"

94 end

95 else

96 -- Class 3: build a fresh pseudo-poem carrying the catalog image as a

97 -- normal attachment. The attachment keeps the FULL relative_path (not

98 -- just the basename) so render_attachment_images can namespace it the

99 -- same way flatten_media_files did -- output/media/<source>/<subpath>.

100 -- Passing only the basename used to work when media was flat, but that

101 -- is exactly what let same-named art images collide; the full path

102 -- carries the source + subdirs that keep them distinct. fname stays

103 -- the basename purely for the human-facing title/type.

104 local fname = basename(rec.relative_path)

105 poems_data.poems[#poems_data.poems + 1] = {

106 poem_index = pidx,

107 id = "img-" .. tostring(pidx),

108 is_image = true,

109 image_class = 3,

110 category = "image",

111 content = "",

112 creation_date = rec.creation_date,

113 display_title = rec.display_title or fname,

114 gallery_anchor = rec.gallery_anchor, -- deep-link to the chrono gallery

115 attachments = {{

116 relative_path = rec.relative_path,

117 media_type = media_type_for(fname),

118 width = rec.width, height = rec.height,

119 description = rec.display_title or fname,

120 }},

121 }

122 end

123 end

124 return poems_data

125end

126-- }}}

127

128-- Document-relative bases: "up to the site root, then down to the target." These

129-- image entries are only ever rendered into poem pages, which live one directory

130-- below the root (output/similar/, output/different/, output/chronological/), so

131-- the prefix is "../". Relative paths resolve identically whether opened locally

132-- from any folder or served on the site -- no per-environment conversion. (If an

133-- image entry were ever rendered at another depth, this prefix would move with

134-- the page; today every caller is depth 1.) flatten_media_files puts each image

135-- at output/media/<source>/<subpath>, which "../media/" + media_href() reaches.

136local MEDIA_BASE = "../media/"

137local GALLERY_BASE = "../gallery/chronological.html#"

138

139-- {{{ function M.text_image_link()

140-- For a TEXT+IMAGE post (a normal poem that also carries an image attachment),

141-- a direct link to the image file, always labelled "image.png" regardless of

142-- the real filename. These pictures have no gallery entry/name of their own, so

143-- this gives the reader a way to open the image. Returns "" when there is no

144-- image attachment (pure-text poems get nothing).

145function M.text_image_link(poem)

146 local att = poem.attachments and poem.attachments[1]

147 if not att then return "" end

148 local raw = att.relative_path or att.url or ""

149 if raw == "" then return "" end

150 -- media_href keeps art's source+subdir structure (collision-safe) and

151 -- url-encodes; Mastodon hashes collapse to the bare name. Matches the <img>

152 -- src in format_image_entry and where flatten_media_files placed the file.

153 return string.format('<a href="%s%s">image.png</a>', MEDIA_BASE, media_href(raw))

154end

155-- }}}

156

157-- {{{ function M.format_image_entry()

158-- Render a ranked IMAGE as a compact, CSS-free box: a marker + the

159-- source-qualified title, the image(s), then a closing rule. Self-contained

160-- (builds its own <img> from the attachment) so it renders identically in the

161-- main thread and in each effil worker without needing their private helpers.

162function M.format_image_entry(poem)

163 local title = poem.display_title or "image"

164 local esc = title:gsub("&", "&"):gsub("<", "<"):gsub(">", ">")

165 local imgs = {}

166 for _, att in ipairs(poem.attachments or {}) do

167 -- media_href namespaces art by source+subdir (so same-named pieces don't

168 -- collide in output/media/) and url-encodes; Mastodon hashes stay flat.

169 local src = MEDIA_BASE .. media_href(att.relative_path or att.url or "")

170 if att.width and att.height then

171 imgs[#imgs + 1] = string.format(

172 ' <img src="%s" alt="%s" loading="lazy" width="%d" height="%d" style="display:block; max-width:min(100%%,800px); height:auto">',

173 src, esc, att.width, att.height)

174 else

175 imgs[#imgs + 1] = string.format(

176 ' <img src="%s" alt="%s" loading="lazy" style="display:block; max-width:min(100%%,800px); height:auto">',

177 src, esc)

178 end

179 end

180 -- For a standalone catalog image, link the title to its spot on the

181 -- chronological gallery page (Issue 9-013 gallery links). Image-only posts

182 -- carry no gallery_anchor, so their title stays plain text.

183 local title_html = esc

184 if poem.gallery_anchor then

185 title_html = string.format('<a href="%s%s">%s</a>', GALLERY_BASE, poem.gallery_anchor, esc)

186 end

187 return table.concat({

188 "<hr>",

189 string.format('<font color="#868E96"><b>🖼 %s</b></font>', title_html),

190 table.concat(imgs, "\n"),

191 "<hr>",

192 "",

193 }, "\n")

194end

195-- }}}

196

197-- {{{ function M.reset_cache()

198-- Test hook: drop the memoized manifest so fixtures don't bleed between cases.

199function M.reset_cache()

200 manifest_cache = nil

201end

202-- }}}

203

204return M

205