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koreader/frontend/ui/wikipedia.lua
poire-z c3a938aad6
bump crengine: alternative TOC, no page break on borders (#4011)
Includes:
- Avoid page break between a node and its borders
- Allow building an alternative TOC from document headings

On CRE documents, allows toggling between original TOC and an
alternative TOC with long-press on the "Table of content" menu
item.

Also update the Wikipedia stylesheet to further avoid
page-breaks between images and their caption, so a full
bordered wikipedia thumbnail is always full on a single page.
2018-06-14 00:46:52 +02:00

1307 lines
57 KiB
Lua

local JSON = require("json")
local RenderImage = require("ui/renderimage")
local Screen = require("device").screen
local ffiutil = require("ffi/util")
local logger = require("logger")
local util = require("util")
local _ = require("gettext")
local T = ffiutil.template
--[[
-- Query wikipedia using Wikimedia Web API.
-- https://en.wikipedia.org/w/api.php?format=jsonfm&action=query&generator=search&gsrnamespace=0&gsrsearch=ereader&gsrlimit=10&prop=extracts&exintro&explaintext&exlimit=max
-- https://en.wikipedia.org/w/api.php?action=query&prop=extracts&format=jsonfm&explaintext=&redirects=&titles=E-reader
--
-- To get parsed HTML :
-- https://en.wikipedia.org/w/api.php?action=parse&page=E-book
-- https://en.wikipedia.org/w/api.php?action=parse&page=E-book&prop=text|sections|displaytitle|revid&disablelimitreport=&disableeditsection
-- https://www.mediawiki.org/wiki/API:Parsing_wikitext#parse
--]]
local Wikipedia = {
wiki_server = "https://%s.wikipedia.org",
wiki_path = "/w/api.php",
default_lang = "en",
-- See https://www.mediawiki.org/wiki/API:Main_page for details.
-- Search query, returns introductory texts (+ main thumbnail image)
wiki_search_params = {
action = "query",
generator = "search",
gsrnamespace = "0",
-- gsrsearch = nil, -- text to lookup, will be added below
gsrlimit = 20, -- max nb of results to get
exlimit = "max",
prop = "extracts|info|pageimages", -- 'extracts' to get text, 'info' to get full page length
format = "json",
explaintext = "",
exintro = "",
-- We have to use 'exintro=' to get extracts for ALL results
-- (otherwise, we get the full text for only the first result, and
-- no text at all for the others
},
-- Full article, parsed to output text (+ main thumbnail image)
wiki_full_params = {
action = "query",
prop = "extracts|pageimages",
format = "json",
-- exintro = nil, -- get more than only the intro
explaintext = "",
redirects = "",
-- title = nil, -- text to lookup, will be added below
},
-- Full article, parsed to output HTML, for Save as EPUB
wiki_phtml_params = {
action = "parse",
format = "json",
-- we only need the following informations
prop = "text|sections|displaytitle|revid",
-- page = nil, -- text to lookup, will be added below
-- disabletoc = "", -- if we want to remove toc IN html
disablelimitreport = "",
disableeditsection = "",
},
-- Full article, parsed to output HTML, for images extraction
-- (used with full article as text, if "show more images" enabled)
wiki_images_params = { -- same as previous one, with just text html
action = "parse",
format = "json",
-- we only need the following informations
prop = "text",
-- page = nil, -- text to lookup, will be added below
redirects = "",
disabletoc = "", -- remove toc in html
disablelimitreport = "",
disableeditsection = "",
},
-- There is an alternative for obtaining page's images:
-- prop=imageinfo&action=query&iiprop=url|dimensions|mime|extmetadata&generator=images&pageids=49448&iiurlwidth=100&iiextmetadatafilter=ImageDescription
-- but it gives all images (including wikipedia icons) in any order, without
-- any score or information that would help considering if they matter or not
--
-- Allow for disabling prettifying full page text
wiki_prettify = G_reader_settings:nilOrTrue("wikipedia_prettify"),
-- Can be set so HTTP requests will be done under Trapper and
-- be interruptible
trap_widget = nil,
-- For actions done with Trapper:dismissable methods, we may throw
-- and error() with this code. We make the value of this error
-- accessible here so that caller can know it's a user dismiss.
dismissed_error_code = "Interrupted by user",
}
function Wikipedia:getWikiServer(lang)
return string.format(self.wiki_server, lang or self.default_lang)
end
-- Codes that getUrlContent may get from requester.request()
local TIMEOUT_CODE = "timeout" -- from socket.lua
local MAXTIME_CODE = "maxtime reached" -- from sink_table_with_maxtime
-- Sink that stores into a table, aborting if maxtime has elapsed
local function sink_table_with_maxtime(t, maxtime)
-- Start counting as soon as this sink is created
local start_secs, start_usecs = ffiutil.gettime()
local starttime = start_secs + start_usecs/1000000
t = t or {}
local f = function(chunk, err)
local secs, usecs = ffiutil.gettime()
if secs + usecs/1000000 - starttime > maxtime then
return nil, MAXTIME_CODE
end
if chunk then table.insert(t, chunk) end
return 1
end
return f, t
end
-- Get URL content
local function getUrlContent(url, timeout, maxtime)
local socket = require('socket')
local ltn12 = require('ltn12')
local http = require('socket.http')
local https = require('ssl.https')
local requester
if url:sub(1,7) == "http://" then
requester = http
elseif url:sub(1,8) == "https://" then
requester = https
else
return false, "Unsupported protocol"
end
if not timeout then timeout = 10 end
-- timeout needs to be set to 'http', even if we use 'https'
http.TIMEOUT, https.TIMEOUT = timeout, timeout
local request = {}
local sink = {}
request['url'] = url
request['method'] = 'GET'
-- 'timeout' delay works on socket, and is triggered when
-- that time has passed trying to connect, or after connection
-- when no data has been read for this time.
-- On a slow connection, it may not be triggered (as we could read
-- 1 byte every 1 second, not triggering any timeout).
-- 'maxtime' can be provided to overcome that, and we start counting
-- as soon as the first content byte is received (but it is checked
-- for only when data is received).
-- Setting 'maxtime' and 'timeout' gives more chance to abort the request when
-- it takes too much time (in the worst case: in timeout+maxtime seconds).
-- But time taken by DNS lookup cannot easily be accounted for, so
-- a request may (when dns lookup takes time) exceed timeout and maxtime...
if maxtime then
request['sink'] = sink_table_with_maxtime(sink, maxtime)
else
request['sink'] = ltn12.sink.table(sink)
end
local code, headers, status = socket.skip(1, requester.request(request))
local content = table.concat(sink) -- empty or content accumulated till now
-- logger.dbg("code:", code)
-- logger.dbg("headers:", headers)
-- logger.dbg("status:", status)
-- logger.dbg("#content:", #content)
if code == TIMEOUT_CODE or code == MAXTIME_CODE then
logger.warn("request interrupted:", code)
return false, code
end
if headers == nil then
logger.warn("No HTTP headers:", code, status)
return false, "Network or remote server unavailable"
end
if not code or string.sub(code, 1, 1) ~= "2" then -- all 200..299 HTTP codes are OK
logger.warn("HTTP status not okay:", code, status)
return false, "Remote server error or unavailable"
end
if headers and headers["content-length"] then
-- Check we really got the announced content size
local content_length = tonumber(headers["content-length"])
if #content ~= content_length then
return false, "Incomplete content received"
end
end
return true, content
end
function Wikipedia:setTrapWidget(trap_widget)
self.trap_widget = trap_widget
end
function Wikipedia:resetTrapWidget()
self.trap_widget = nil
end
-- Possible values for page_type parameter to loadPage()
local WIKIPEDIA_INTRO = 1
local WIKIPEDIA_FULL = 2
local WIKIPEDIA_PHTML = 3
local WIKIPEDIA_IMAGES = 4
--[[
-- return decoded JSON table from Wikipedia
--]]
function Wikipedia:loadPage(text, lang, page_type, plain)
local url = require('socket.url')
local query = ""
local parsed = url.parse(self:getWikiServer(lang))
parsed.path = self.wiki_path
if page_type == WIKIPEDIA_INTRO then -- search query
self.wiki_search_params.explaintext = plain and "" or nil
for k,v in pairs(self.wiki_search_params) do
query = string.format("%s%s=%s&", query, k, v)
end
parsed.query = query .. "gsrsearch=" .. url.escape(text)
elseif page_type == WIKIPEDIA_FULL then -- full page content
self.wiki_full_params.explaintext = plain and "" or nil
for k,v in pairs(self.wiki_full_params) do
query = string.format("%s%s=%s&", query, k, v)
end
parsed.query = query .. "titles=" .. url.escape(text)
elseif page_type == WIKIPEDIA_PHTML then -- parsed html page content
for k,v in pairs(self.wiki_phtml_params) do
query = string.format("%s%s=%s&", query, k, v)
end
parsed.query = query .. "page=" .. url.escape(text)
elseif page_type == WIKIPEDIA_IMAGES then -- images found in page html
for k,v in pairs(self.wiki_images_params) do
query = string.format("%s%s=%s&", query, k, v)
end
parsed.query = query .. "page=" .. url.escape(text)
else
return
end
local built_url = url.build(parsed)
local completed, success, content
if self.trap_widget then -- if previously set with Wikipedia:setTrapWidget()
local Trapper = require("ui/trapper")
local timeout, maxtime = 30, 60
-- We use dismissableRunInSubprocess with complex return values:
completed, success, content = Trapper:dismissableRunInSubprocess(function()
return getUrlContent(built_url, timeout, maxtime)
end, self.trap_widget)
if not completed then
error(self.dismissed_error_code) -- "Interrupted by user"
end
else
local timeout, maxtime = 10, 60
success, content = getUrlContent(built_url, timeout, maxtime)
end
if not success then
error(content)
end
if content ~= "" and string.sub(content, 1,1) == "{" then
local ok, result = pcall(JSON.decode, content)
if ok and result then
logger.dbg("wiki result json:", result)
return result
else
logger.warn("wiki result json decoding error:", result)
error("Failed decoding JSON")
end
else
logger.warn("wiki response is not json:", content)
error("Response is not JSON")
end
end
-- search wikipedia and get intros for results
function Wikipedia:searchAndGetIntros(text, lang)
local result = self:loadPage(text, lang, WIKIPEDIA_INTRO, true)
if result then
local query = result.query
if query then
local show_image = G_reader_settings:nilOrTrue("wikipedia_show_image")
-- Scale wikipedia normalized (we hope) thumbnail by 2 (adjusted
-- to screen size/dpi) for intros (and x8 more for highres image)
local image_size_factor = Screen:scaleBySize(200)/100.0
if show_image then
for pageid, page in pairs(query.pages) do
self:addImages(page, lang, false, image_size_factor, 8)
end
end
return query.pages
end
end
end
-- get full content of a wiki page
function Wikipedia:getFullPage(wiki_title, lang)
local result = self:loadPage(wiki_title, lang, WIKIPEDIA_FULL, true)
if result then
local query = result.query
if query then
local show_image = G_reader_settings:nilOrTrue("wikipedia_show_image")
local show_more_images = G_reader_settings:nilOrTrue("wikipedia_show_more_images")
-- Scale wikipedia normalized (we hope) thumbnails by 4 (adjusted
-- to screen size/dpi) for full page (and this *4 for highres image)
local image_size_factor = Screen:scaleBySize(400)/100.0
if self.wiki_prettify or show_image then
for pageid, page in pairs(query.pages) do
if self.wiki_prettify and page.extract then
-- Prettification of the plain text full page
page.extract = self:prettifyText(page.extract)
end
if show_image then
self:addImages(page, lang, show_more_images, image_size_factor, 4)
end
end
end
return query.pages
end
end
end
-- get parsed html content and other infos of a wiki page
function Wikipedia:getFullPageHtml(wiki_title, lang)
local result = self:loadPage(wiki_title, lang, WIKIPEDIA_PHTML, true)
if result and result.parse then
return result.parse
end
if result.error and result.error.info then
error(result.error.info)
end
end
-- get images extracted from parsed html
function Wikipedia:getFullPageImages(wiki_title, lang)
local images = {} -- will be returned, each in a format similar to page.thumbnail
local result = self:loadPage(wiki_title, lang, WIKIPEDIA_IMAGES, true)
if result and result.parse and result.parse.text and result.parse.text["*"] then
local html = result.parse.text["*"] -- html content
local url = require('socket.url')
local wiki_base_url = self:getWikiServer(lang)
local thumbs = {} -- bits of HTML containing an image
-- We first try to catch images in <div class=thumbinner>, which should exclude
-- wikipedia icons, flags... These seem to all end with a double </div>.
for thtml in html:gmatch([[<div class="thumbinner".-</div>%s*</div>]]) do
table.insert(thumbs, thtml)
end
-- We then also try to catch images in galleries (which often are less
-- interesting than those in thumbinner) as a 2nd set.
for thtml in html:gmatch([[<li class="gallerybox".-<div class="thumb".-</div>%s*</div>%s*<div class="gallerytext">.-</div>%s*</div>]]) do
table.insert(thumbs, thtml)
end
-- We may miss some interesting images in the page's top right table, but
-- there's no easy way to distinguish them from icons/flags in this table...
for _, thtml in ipairs(thumbs) do
-- We get <a href="/wiki/File:real_file_name.jpg (or /wiki/Fichier:real_file_name.jpg
-- depending on Wikipedia lang)
local filename = thtml:match([[<a href="/wiki/[^:]*:([^"]*)" class="image"]])
if filename then
filename = url.unescape(filename)
end
logger.dbg("found image with filename:", filename)
-- logger.dbg(thtml)
local timg, tremain = thtml:match([[(<img .->)(.*)]])
if timg and tremain then
-- (Should we discard those without caption ?)
local caption = tremain and util.htmlToPlainText(tremain)
if caption == "" then caption = nil end
logger.dbg(" caption:", caption)
-- logger.dbg(timg)
local src = timg:match([[src="([^"]*)"]])
if src and src ~= "" then
if src:sub(1,2) == "//" then
src = "https:" .. src
elseif src:sub(1,1) == "/" then -- non absolute url
src = wiki_base_url .. src
end
local width = tonumber(timg:match([[width="([^"]*)"]]))
local height = tonumber(timg:match([[height="([^"]*)"]]))
-- Ignore img without width and height, which should exlude
-- javascript maps and other unsupported stuff
if width and height then
-- Images in the html we got seem to be x4.5 the size of
-- the thumbnail we get with searchAndGetIntros() or
-- getFullPage(). Normalize them to the size of the thumbnail,
-- so we can resize them all later with the same rules.
width = math.ceil(width/4.5)
height = math.ceil(height/4.5)
-- No need to adjust width in src url here, as it will be
-- done in addImages() anyway
-- src = src:gsub("(.*/)%d+(px-[^/]*)", "%1"..width.."%2")
logger.dbg(" size:", width, "x", height, "url:", src)
table.insert(images, {
source = src,
width = width,
height = height,
filename = filename,
caption = caption,
})
end
end
end
end
end
return images
end
-- Function wrapped and plugged to image objects returned by :addImages()
local function image_load_bb_func(image, highres)
local source, trap_widget
if not highres then
-- We use an invisible widget that will resend the dismiss event,
-- so that image loading in TextBoxWdiget is unobtrusive and
-- interruptible
trap_widget = false
source = image.source
else
-- We need to let the user know image loading is happening,
-- with a discreet TrapWidget
trap_widget = _("Loading high-res image… (tap to cancel)")
source = image.hi_source
end
-- Image may be big or take some time to be resized on wikipedia servers.
-- As we use dismissableRunInSubprocess and can interrupt this loading,
-- we can use quite high timeouts
local timeout, maxtime = 60, 120
logger.dbg("fetching", source)
local Trapper = require("ui/trapper")
-- We use dismissableRunInSubprocess with simple string return value to
-- avoid dump()/load() a long string of image bytes
local completed, data = Trapper:dismissableRunInSubprocess(function()
local success, data = getUrlContent(source, timeout, maxtime)
-- With simple string value, we're not able to return the failure
-- reason, so log it here
if not success then
logger.warn("failed fetching image from", source, ":", data)
end
return success and data or nil
end, trap_widget, true) -- task_returns_simple_string=true
local success = data and true or false -- guess success from data
if not completed then
logger.dbg("image fetching interrupted by user")
return true -- let caller know it was interrupted
end
if not success then
-- log it again (on Android, log from sub-process seem to not work)
logger.warn("failed fetching image from", source)
return
end
logger.dbg(" fetched", #data)
local bb
if not highres then
-- For low-res, we should ensure the image we got from wikipedia is
-- the right size, so it does not overflow our reserved area
-- (TextBoxWidget may have adjusted image.width and height)
-- We don't get animated GIF multiple frames to keep TextBoxWidget
-- simple: they will be available when viewed in highres
bb = RenderImage:renderImageData(data, #data, false, image.width, image.height)
else
-- We provide want_frames=true for highres images, so ImageViewer
-- can display animated GIF
-- No need for width and height for high-res
bb = RenderImage:renderImageData(data, #data, true)
end
if not bb then
logger.warn("failed building image from", source)
return
end
if not highres then
image.bb = bb
else
image.hi_bb = bb
end
end
function Wikipedia:addImages(page, lang, more_images, image_size_factor, hi_image_size_factor)
-- List of images, table with keys as expected by TextBoxWidget
page.images = {}
-- List of wikipedia images data structures (page.thumbnail and images
-- extracted from html) made to have the same keys for common processing
local wimages = {}
-- We got what Wikipedia scored as the most interesting image for this
-- page in page.thumbnail, and its filename in page.pageimage, ie:
-- "thumbnail": {
-- "source": "https://upload.wikimedia.org/wikipedia/commons/thumb/4/45/Reading_on_the_bus_train_or_transit.jpg/37px-Reading_on_the_bus_train_or_transit.jpg",
-- "width": 37,
-- "height": 50
-- },
-- "pageimage": "Reading_on_the_bus_train_or_transit.jpg"
--
local first_image_filename = nil
if page.thumbnail and page.thumbnail.source then
page.thumbnail.filename = page.pageimage
first_image_filename = page.pageimage
table.insert(wimages, page.thumbnail)
end
-- To get more images, we need to make a second request to wikipedia
if more_images then
local ok, images_or_err = pcall(Wikipedia.getFullPageImages, Wikipedia, page.title, lang)
if not ok then
logger.warn("error getting more images", images_or_err)
else
for _, wimage in ipairs(images_or_err) do
if first_image_filename and wimage.filename == first_image_filename then
-- We got the same image as the thumbnail one, but it may have
-- a caption: replace thumbnail one with this one
table.remove(wimages, 1)
table.insert(wimages, 1, wimage)
else
table.insert(wimages, wimage)
end
end
end
end
-- All our wimages now have the keys: source, width, height, filename, caption
for _, wimage in ipairs(wimages) do
-- We trust wikipedia, and our x4.5 factor in :getFullPageImages(), for adequate
-- and homogeneous images' sizes. We'll just scale them according to the
-- provided 'image_size_factor' (which should account for screen size/DPI)
local width = wimage.width or 100 -- in case we don't get any width or height
local height = wimage.height or 100
-- Give a little boost in size to thin images
if width < height / 2 or height < width / 2 then
width = width * 1.3
height = height * 1.3
end
width = math.ceil(width * image_size_factor)
height = math.ceil(height * image_size_factor)
-- All wikipedia image urls like .../wikipedia/commons/A/BC/<filename>
-- or .../wikipedia/commons/thumb/A/BC/<filename>/<width>px-<filename>
-- can be transformed to another url with a requested new_width with the form:
-- /wikipedia/commons/thumb/A/BC/<filename>/<new_width>px-<filename>
-- (Additionally, the image format can be changed by appending .png,
-- .jpg or .gif to it)
-- The resize is so done on Wikipedia servers from the source image for
-- the best quality.
local source = wimage.source:gsub("(.*/)%d+(px-[^/]*)", "%1"..width.."%2")
-- We build values for a high resolution version of the image, to be displayed
-- with ImageViewer (x 4 by default)
local hi_width = width * (hi_image_size_factor or 4)
local hi_height = height * (hi_image_size_factor or 4)
local hi_source = wimage.source:gsub("(.*/)%d+(px-[^/]*)", "%1"..hi_width.."%2")
local title = wimage.filename
if title then
title = title:gsub("_", " ")
end
local image = {
-- As expected by TextBoxWidget (with additional source and
-- hi_source, that will be used by load_bb_func)
title = title,
caption = wimage.caption,
source = source,
width = width,
height = height,
bb = nil, -- will be loaded and build only if needed
hi_source = hi_source,
hi_width = hi_width,
hi_height = hi_height,
hi_bb = nil, -- will be loaded and build only if needed
}
-- If bb or hi_bb is nil, TextBoxWidget will call a method named "load_bb_func"
image.load_bb_func = function(highres)
return image_load_bb_func(image, highres)
end
table.insert(page.images, image)
end
end
-- UTF8 of unicode geometrical shapes we can use to replace
-- the "=== title ===" of wkipedia plaintext pages
-- These chosen ones are available in most fonts (prettier symbols
-- exist in unicode, but are available in a few fonts only) and
-- have a quite consistent size/weight in all fonts.
local th1_sym = "\xE2\x96\x88" -- full block (big black rectangle) (never met, only for web page title?)
local th2_sym = "\xE2\x96\x89" -- big black square
local th3_sym = "\xC2\xA0\xE2\x97\xA4" -- black upper left triangle (indented, nicer)
local th4_sym = "\xE2\x97\x86" -- black diamond
local th5_sym = "\xE2\x9C\xBF" -- black florette
local th6_sym = "\xE2\x9D\x96" -- black diamond minus white x
-- Others available in most fonts
-- local thX_sym = "\xE2\x9C\x9A" -- heavy greek cross
-- local thX_sym = "\xE2\x97\xA2" -- black lower right triangle
-- local thX_sym = "\xE2\x97\x89" -- fish eye
-- local thX_sym = "\xE2\x96\x97" -- quadrant lower right
-- For optional prettification of the plain text full page
function Wikipedia:prettifyText(text)
-- We use \a for an additional leading \n that we don't want shortened later
text = text:gsub("\n= ", "\n\a"..th1_sym.." ") -- 2 empty lines before
text = text:gsub("\n== ", "\n\a"..th2_sym.." ") -- 2 empty lines before
text = text:gsub("\n=== ", "\n"..th3_sym.." ")
text = text:gsub("\n==== ", "\n"..th4_sym.." ")
text = text:gsub("\n===== ", "\n"..th5_sym.." ")
text = text:gsub("\n====== ", "\n"..th6_sym.." ")
text = text:gsub("Modifier ==", " ==") -- fr wikipedia fix for some articles modified by clumsy editors
text = text:gsub("==$", "==\n") -- for a </hN> at end of text to be matched by next gsub
text = text:gsub(" ===?\n+", "\n\n") -- </h2> to </h3> : empty line after
text = text:gsub(" ====+\n+", "\n") -- </h4> to </hN> : single \n, no empty line
text = text:gsub("\n\n+\xE2\x80\x94", "\n\xE2\x80\x94") -- em dash, used for quote author, make it stick to prev text
text = text:gsub("\n +\n", "\n") -- trim lines full of only spaces (often seen in math formulas)
text = text:gsub("^\n*", "") -- trim new lines at start
text = text:gsub("\n*$", "") -- trim new lines at end
text = text:gsub("\n\n+", "\n\n") -- shorten multiple new lines
text = text:gsub("\a", "\n") -- re-add our wished \n
return text
end
-- UTF8 of unicode geometrical shapes we'll prepend to wikipedia section headers,
-- to help identifying hierarchy (othewise, the small font size differences helps).
-- Best if identical to the ones used above for prettifying full plain text page.
-- These chosen ones are available in most fonts (prettier symbols
-- exist in unicode, but are available in a few fonts only) and
-- have a quite consistent size/weight in all fonts.
local h1_sym = "\xE2\x96\x88" -- full block (big black rectangle) (never met, only for web page title?)
local h2_sym = "\xE2\x96\x89" -- big black square
local h3_sym = "\xE2\x97\xA4" -- black upper left triangle
local h4_sym = "\xE2\x97\x86" -- black diamond
local h5_sym = "\xE2\x9C\xBF" -- black florette
local h6_sym = "\xE2\x9D\x96" -- black diamond minus white x
-- Other available ones in most fonts
-- local hXsym = "\xE2\x9C\x9A" -- heavy greek cross
-- local hXsym = "\xE2\x97\xA2" -- black lower right triangle
-- local hXsym = "\xE2\x97\x89" -- fish eye
-- local hXsym = "\xE2\x96\x97" -- quadrant lower right
local ext_to_mimetype = {
png = "image/png",
jpg = "image/jpeg",
jpeg = "image/jpeg",
gif = "image/gif",
svg = "image/svg+xml",
html= "application/xhtml+xml",
xhtml= "application/xhtml+xml",
ncx = "application/x-dtbncx+xml",
js = "text/javascript",
css = "text/css",
otf = "application/opentype",
ttf = "application/truetype",
woff = "application/font-woff",
}
-- Create an epub file (with possibly images)
function Wikipedia:createEpub(epub_path, page, lang, with_images)
-- Use Trapper to display progress and ask questions through the UI.
-- We need to have been Trapper.wrap()'ed for UI to be used, otherwise
-- Trapper:info() and Trapper:confirm() will just use logger.
local UI = require("ui/trapper")
UI:info(_("Retrieving Wikipedia article…"))
local ok, phtml = pcall(self.getFullPageHtml, self, page, lang)
if not ok then
UI:info(phtml) -- display error in InfoMessage
-- Sleep a bit to make that error seen
ffiutil.sleep(2)
UI:reset()
return false
end
-- We may need to build absolute urls for non-absolute links and images urls
local wiki_base_url = self:getWikiServer(lang)
-- Get infos from wikipedia result
-- (see example at https://en.wikipedia.org/w/api.php?action=parse&page=E-book&prop=text|sections|displaytitle|revid&disablelimitreport=&disableeditsection)
local cancelled = false
local html = phtml.text["*"] -- html content
local page_cleaned = page:gsub("_", " ") -- page title
local page_htmltitle = phtml.displaytitle -- page title with possible <sup> tags
-- We need to encode plain '&' in those so we can put them in XML/HTML
-- We wouldn't need to escape as many as util.htmlEntitiesToUtf8() does, but
-- we need to to not mess existing ones ('&nbsp;' may happen) with our '&'
-- encodes. (We don't escape < or > as these JSON strings may contain HTML tags)
page_cleaned = util.htmlEntitiesToUtf8(page_cleaned):gsub("&", "&#38;")
page_htmltitle = util.htmlEntitiesToUtf8(page_htmltitle):gsub("&", "&#38;")
local sections = phtml.sections -- Wikipedia provided TOC
local bookid = string.format("wikipedia_%s_%s_%s", lang, phtml.pageid, phtml.revid)
-- Not sure if this bookid may ever be used by indexing software/calibre, but if it is,
-- should it changes if content is updated (as now, including the wikipedia revisionId),
-- or should it stays the same even if revid changes (content of the same book updated).
-- We need to find images in HTML to tell how many when asking user if they should be included
local images = {}
local seen_images = {}
local imagenum = 1
local cover_imgid = nil -- best candidate for cover among our images
local processImg = function(img_tag)
local src = img_tag:match([[src="([^"]*)"]])
if src == nil or src == "" then
logger.info("no src found in ", img_tag)
return nil
end
if src:sub(1,2) == "//" then
src = "https:" .. src -- Wikipedia redirects from http to https, so use https
elseif src:sub(1,1) == "/" then -- non absolute url
src = wiki_base_url .. src
end
-- Some SVG urls don't have any extension, like:
-- "/api/rest_v1/media/math/render/svg/154a342afea5a9f13caf1a5bb6acd5c4e69733b6""
-- Furthermore, as of early 2018, it looks like most (all?) mathematical SVG
-- obtained from such urls use features not supported by crengine's nanosvg
-- renderer (so, they are displayed as a blank square).
-- But we can get a PNG version of it thanks to wikipedia APIs :
-- https://wikimedia.org/api/rest_v1/#!/Math/get_media_math_render_format_hash
-- We tweak the url now (and fix the mimetype below), before checking for
-- duplicates in seen_images.
-- Think about disabling that when nanosvg gets better!
if src:find("/math/render/svg/") then
src = src:gsub("/math/render/svg/", "/math/render/png/")
end
local cur_image
if seen_images[src] then -- already seen
cur_image = seen_images[src]
else
local src_ext = src
if src_ext:find("?") then -- "/w/extensions/wikihiero/img/hiero_D22.png?0b8f1"
src_ext = src_ext:match("(.-)%?") -- remove ?blah
end
local ext = src_ext:match(".*%.(%S%S%S?%S?%S?)$") -- extensions are only 2 to 5 chars
if ext == nil or ext == "" then
if src_ext:find("/math/render/png/") then -- tweaked above
ext = "png"
else
-- we won't know what mimetype to use, ignore it
logger.info("no file extension found in ", src)
return nil
end
end
ext = ext:lower()
local imgid = string.format("img%05d", imagenum)
local imgpath = string.format("images/%s.%s", imgid, ext)
local mimetype = ext_to_mimetype[ext] or ""
local width = tonumber(img_tag:match([[width="([^"]*)"]]))
local height = tonumber(img_tag:match([[height="([^"]*)"]]))
-- Get higher resolution (2x) image url
local src2x = nil
local srcset = img_tag:match([[srcset="([^"]*)"]])
if srcset then
srcset = " "..srcset.. ", " -- for next pattern to possibly match 1st or last item
src2x = srcset:match([[ (%S+) 2x, ]])
if src2x then
if src2x:sub(1,2) == "//" then
src2x = "https:" .. src2x
elseif src2x:sub(1,1) == "/" then -- non absolute url
src2x = wiki_base_url .. src2x
end
end
end
cur_image = {
imgid = imgid,
imgpath = imgpath,
src = src,
src2x = src2x,
mimetype = mimetype,
width = width,
height = height,
}
table.insert(images, cur_image)
seen_images[src] = cur_image
-- Use first image of reasonable size (not an icon) and portrait-like as cover-image
if not cover_imgid and width and width > 50 and height and height > 50 and height > width then
cover_imgid = imgid
end
imagenum = imagenum + 1
end
-- crengine will NOT use width and height attributes, but it will use
-- those found in a style attribute.
-- If we get src2x images, crengine will scale them down to the 1x image size
-- (less space wasted by images while reading), but the 2x quality will be
-- there when image is viewed full screen with ImageViewer widget.
local style_props = {}
if cur_image.width then
table.insert(style_props, string.format("width: %spx", cur_image.width))
end
if cur_image.height then
table.insert(style_props, string.format("height: %spx", cur_image.height))
end
local style = table.concat(style_props, "; ")
return string.format([[<img src="%s" style="%s" alt=""/>]], cur_image.imgpath, style)
end
html = html:gsub("(<%s*img [^>]*>)", processImg)
logger.dbg("Images found in html:", images)
-- See what to do with images
local include_images = false
local use_img_2x = false
if with_images then
-- If no UI (Trapper:wrap() not called), UI:confirm() will answer true
if #images > 0 then
include_images = UI:confirm(T(_("This article contains %1 images.\nWould you like to download and include them in the generated EPUB file?"), #images), _("Don't include"), _("Include"))
if include_images then
use_img_2x = UI:confirm(_("Would you like to use slightly higher quality images? This will result in a bigger file size."), _("Standard quality"), _("Higher quality"))
end
else
UI:info(_("This article does not contain any images."))
ffiutil.sleep(1) -- Let the user see that
end
end
if not include_images then
-- Remove img tags to avoid little blank squares of missing images
html = html:gsub("<%s*img [^>]*>", "")
-- We could remove the whole image container <div class="thumb"...> ,
-- but it's a lot of nested <div> and not easy to do.
-- So the user will see the image legends and know a bit about
-- the images he chose to not get.
end
UI:info(_("Building EPUB…"))
-- Open the zip file (with .tmp for now, as crengine may still
-- have a handle to the final epub_path, and we don't want to
-- delete a good one if we fail/cancel later)
local epub_path_tmp = epub_path .. ".tmp"
local ZipWriter = require("ffi/zipwriter")
local epub = ZipWriter:new{}
if not epub:open(epub_path_tmp) then
return false
end
-- We now create and add all the required epub files
-- ----------------------------------------------------------------
-- /mimetype : always "application/epub+zip"
epub:add("mimetype", "application/epub+zip")
-- ----------------------------------------------------------------
-- /META-INF/container.xml : always the same content
epub:add("META-INF/container.xml", [[
<?xml version="1.0"?>
<container version="1.0" xmlns="urn:oasis:names:tc:opendocument:xmlns:container">
<rootfiles>
<rootfile full-path="OEBPS/content.opf" media-type="application/oebps-package+xml"/>
</rootfiles>
</container>]])
-- ----------------------------------------------------------------
-- OEBPS/content.opf : metadata + list of other files (paths relative to OEBPS/ directory)
-- Other possible items in this file that are of no interest to crengine :
-- In <manifest> :
-- <item id="cover" href="title.html" media-type="application/xhtml+xml"/>
-- <item id="cover-image" href="images/cover.png" media-type="image/png"/>
-- (crengine only uses <meta name="cover" content="cover-image" /> to get the cover image)
-- In <spine toc="ncx"> :
-- <itemref idref="cover" linear="no"/>
-- And a <guide> section :
-- <guide>
-- <reference href="title.html" type="cover" title="Cover"/>
-- <reference href="toc.html" type="toc" title="Table of Contents" href="toc.html" />
-- </guide>
local koreader_version = "KOReader"
if lfs.attributes("git-rev", "mode") == "file" then
koreader_version = "KOReader "..io.open("git-rev", "r"):read()
end
local content_opf_parts = {}
-- head
local meta_cover = "<!-- no cover image -->"
if include_images and cover_imgid then
meta_cover = string.format([[<meta name="cover" content="%s"/>]], cover_imgid)
end
table.insert(content_opf_parts, string.format([[
<?xml version='1.0' encoding='utf-8'?>
<package xmlns="http://www.idpf.org/2007/opf"
xmlns:dc="http://purl.org/dc/elements/1.1/"
unique-identifier="bookid" version="2.0">
<metadata>
<dc:title>%s</dc:title>
<dc:creator>Wikipedia %s</dc:creator>
<dc:identifier id="bookid">%s</dc:identifier>
<dc:language>%s</dc:language>
<dc:publisher>%s</dc:publisher>
%s
</metadata>
<manifest>
<item id="ncx" href="toc.ncx" media-type="application/x-dtbncx+xml"/>
<item id="content" href="content.html" media-type="application/xhtml+xml"/>
<item id="css" href="stylesheet.css" media-type="text/css"/>
]], page_cleaned, lang:upper(), bookid, lang, koreader_version, meta_cover))
-- images files
if include_images then
for inum, img in ipairs(images) do
table.insert(content_opf_parts, string.format([[ <item id="%s" href="%s" media-type="%s"/>%s]], img.imgid, img.imgpath, img.mimetype, "\n"))
end
end
-- tail
table.insert(content_opf_parts, [[
</manifest>
<spine toc="ncx">
<itemref idref="content"/>
</spine>
</package>
]])
epub:add("OEBPS/content.opf", table.concat(content_opf_parts))
-- ----------------------------------------------------------------
-- OEBPS/stylesheet.css
-- crengine will use its own data/epub.css, we just add/fix a few styles
-- to look more alike wikipedia web pages (that the user can ignore
-- with "Embedded Style" off)
epub:add("OEBPS/stylesheet.css", [[
/* make section headers looks left aligned and avoid some page breaks */
h1, h2 {
page-break-before: always;
page-break-after: avoid;
text-align: left;
}
h3, h4, h5, h6 {
page-break-before: auto;
page-break-after: avoid;
text-align: left;
}
/* avoid page breaks around our centered titles on first page */
h1.koreaderwikifrontpage, h5.koreaderwikifrontpage {
page-break-before: avoid;
page-break-inside: avoid;
page-break-after: avoid;
text-align: center;
margin-top: 0em;
}
p.koreaderwikifrontpage {
font-style: italic;
font-size: 90%;
margin: 1em 2em 1em 2em;
}
hr.koreaderwikifrontpage {
margin-left: 20%;
margin-right: 20%;
margin-bottom: 1.2em;
}
/* So many links, make them look like normal text except for underline */
a {
display:inline;
text-decoration: underline;
color: black;
font-weight: normal;
}
/* No underline for links without their href that we removed */
a.newwikinonexistent {
text-decoration: none;
}
/* don't waste left margin for notes and list of pages */
ul, ol {
margin-left: 0em;
}
/* show a box around image thumbnails */
div.thumb {
border: dotted 1px black;
margin: 0.5em 2.5em 0.5em 2.5em;
padding: 0.5em 0.5em 0.2em 0.5em;
padding-top: ]].. (include_images and "0.5em" or "0.15em") .. [[;
text-align: center;
font-size: 90%;
page-break-inside: avoid;
}
/* these are contained in div.thumb, avoid page break in between them */
div.thumbcaption, div.magnify {
page-break-before: avoid;
}
/* show a box around image in gallery list (li.gallery
* is set up a bit differently than div.thumb - we try
* to make them look the same */
li.gallerybox {
list-style-type: none;
border: dotted 1px black;
margin: 0.5em 2.5em 0.5em 2.5em;
padding: 0.5em 0.5em 0.2em 0.5em;
padding-top: ]].. (include_images and "0.5em" or "0.15em") .. [[;
text-align: center;
font-size: 90%;
}
li.gallerybox div.thumb {
border: solid 1px white;
margin: 0;
padding: 0;
page-break-after: avoid;
}
/* override this one often set in style="" with various values */
li.gallerybox div.thumb div {
margin: 0 !important;
}
/* avoid page break between gallery image and text */
div.gallerytext {
page-break-before: avoid;
page-break-inside: avoid;
}
li.gallerybox div.gallerytext p {
text-align: center;
font-size: 90%;
}
.citation {
font-style: italic;
}
/* hide some view/edit/discuss short links displayed as "v m d" */
.nv-view, .nv-edit, .nv-talk {
display: none;
}
/* hiding .noprint may discard some interesting links */
]])
-- ----------------------------------------------------------------
-- OEBPS/toc.ncx : table of content
local toc_ncx_parts = {}
local depth = 0
local cur_level = 0
local np_end = [[</navPoint>]]
local num = 1
-- Add our own first section for first page, with page name as title
table.insert(toc_ncx_parts, string.format([[<navPoint id="navpoint-%s" playOrder="%s"><navLabel><text>%s</text></navLabel><content src="content.html"/>]], num, num, page_cleaned))
table.insert(toc_ncx_parts, np_end)
-- Wikipedia sections items seem to be already sorted by index, so no need to sort
for isec, s in ipairs(sections) do
num = num + 1
-- Some chars in headings are converted to html entities in the
-- wikipedia-generated HTML. We need to do the same in TOC links
-- for the links to be valid.
local s_anchor = s.anchor:gsub("&", "&amp;"):gsub('"', "&quot;"):gsub(">", "&gt;"):gsub("<", "&lt;")
local s_title = string.format("%s %s", s.number, s.line)
-- Titles may include <i> and other html tags: let's remove them as
-- our TOC can only display text
s_title = (s_title:gsub("(%b<>)", ""))
-- We need to do as for page_htmltitle above. But headings can contain
-- html entities for < and > that we need to put back as html entities
s_title = util.htmlEntitiesToUtf8(s_title):gsub("&", "&#38;"):gsub(">", "&gt;"):gsub("<", "&lt;")
local s_level = s.toclevel
if s_level > depth then
depth = s_level -- max depth required in toc.ncx
end
if s_level == cur_level then
table.insert(toc_ncx_parts, np_end) -- close same-level previous navPoint
elseif s_level < cur_level then
table.insert(toc_ncx_parts, np_end) -- close same-level previous navPoint
while s_level < cur_level do -- close all in-between navPoint
table.insert(toc_ncx_parts, np_end)
cur_level = cur_level - 1
end
elseif s_level > cur_level + 1 then
-- a jump from level N to level N+2 or more ... should not happen
-- per epub spec, but we don't know about wikipedia...
-- so we create missing intermediate navPoints with same anchor as current section
while s_level > cur_level + 1 do
table.insert(toc_ncx_parts, "\n"..(" "):rep(cur_level))
table.insert(toc_ncx_parts, string.format([[<navPoint id="navpoint-%s" playOrder="%s"><navLabel><text>-</text></navLabel><content src="content.html#%s"/>]], num, num, s_anchor))
cur_level = cur_level + 1
num = num + 1
end
-- elseif s_level == cur_level + 1 then
-- sublevel, nothing to close, nothing to add
end
cur_level = s_level
table.insert(toc_ncx_parts, "\n"..(" "):rep(cur_level)) -- indentation, in case a person looks at it
table.insert(toc_ncx_parts, string.format([[<navPoint id="navpoint-%s" playOrder="%s"><navLabel><text>%s</text></navLabel><content src="content.html#%s"/>]], num, num, s_title, s_anchor))
end
-- close nested <navPoint>
while cur_level > 0 do
table.insert(toc_ncx_parts, np_end)
cur_level = cur_level - 1
end
-- Prepend NCX head
table.insert(toc_ncx_parts, 1, string.format([[
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE ncx PUBLIC "-//NISO//DTD ncx 2005-1//EN" "http://www.daisy.org/z3986/2005/ncx-2005-1.dtd">
<ncx xmlns="http://www.daisy.org/z3986/2005/ncx/" version="2005-1">
<head>
<meta name="dtb:uid" content="%s"/>
<meta name="dtb:depth" content="%s"/>
<meta name="dtb:totalPageCount" content="0"/>
<meta name="dtb:maxPageNumber" content="0"/>
</head>
<docTitle>
<text>%s</text>
</docTitle>
<navMap>
]], bookid, depth, page_cleaned))
-- Append NCX tail
table.insert(toc_ncx_parts, [[
</navMap>
</ncx>
]])
epub:add("OEBPS/toc.ncx", table.concat(toc_ncx_parts))
-- ----------------------------------------------------------------
-- OEBPS/content.html
-- Some small fixes to Wikipedia HTML to make crengine and the user happier
-- Most images are in a link to the image info page, which is a useless
-- external link for us, so let's remove this link.
html = html:gsub("<a[^>]*>%s*(<%s*img [^>]*>)%s*</a>", "%1")
-- TODO: do something for <li class="gallerybox"...> so they are no more
-- a <li> (crengine displays them one above the other) and can be displayed
-- side by side
-- For some <div class="thumb tright"> , which include nested divs, although
-- perfectly balanced, crengine seems to miss some closing </div> and we
-- end up having our image bordered box including the remaining main wiki text.
-- It looks like this code is supposed to deal with class= containing multiple
-- class names :
-- https://github.com/koreader/crengine/commit/0930ec7230e720c148fd6f231d69558832b4d53a
-- and that it may stumble on some cases.
-- It's all perfectly fine if we make all these div with a single class name
-- html = html:gsub([[<div class="thumb [^"]*">]], [[<div class="thumb">]])
--
-- But we may as well make all class= have a single name to avoid other problems
-- (no real risk with that, as we don't define any style for wikipedia class names,
-- except div.thumb that always appears first).
html = html:gsub([[(<[^>]* class="[^ "]+)%s+[^"]*"]], [[%1"]])
-- crengine seems to consider unknown tag as 'block' elements, so we may
-- want to remove or replace those that should be considered 'inline' elements
html = html:gsub("</?time[^>]*>", "")
-- crengine does not support the <math> family of tags for displaying formulas,
-- which results in lots of space taken by individual character in the formula, each
-- on a single line...
-- Also, usally, these <math> tags are followed by a <img> tag pointing to a
-- SVG version of the formula, that we took care earlier to change the url to
-- point to a PNG version of the formula (which is still not perfect, as it does
-- not adjust to the current html font size, but it is at least readable).
-- So, remove the whole <math>...</math> content
html = html:gsub([[<math xmlns="http://www.w3.org/1998/Math/MathML".-</math>]], "")
-- Fix internal wikipedia links with full server url (including lang) so
-- ReaderLink can notice them and deal with them with a LookupWikipedia event.
-- We need to remove any "?somekey=somevalue" from url (a real "?" part of the
-- wiki_page word would be encoded as %3F, but ReaderLink would get it decoded and
-- would not be able to distinguish them).
-- Do that first (need to be done first) for full links to other language wikipedias
local cleanOtherLangWikiPageTitle = function(wiki_lang, wiki_page)
wiki_page = wiki_page:gsub("%?.*", "")
return string.format([[href="https://%s.wikipedia.org/wiki/%s"]], wiki_lang, wiki_page)
end
html = html:gsub([[href="https?://([^%.]+).wikipedia.org/wiki/([^"]*)"]], cleanOtherLangWikiPageTitle)
-- Now, do it for same wikipedia short urls
local cleanWikiPageTitle = function(wiki_page)
wiki_page = wiki_page:gsub("%?.*", "")
return string.format([[href="%s/wiki/%s"]], wiki_base_url, wiki_page)
end
html = html:gsub([[href="/wiki/([^"]*)"]], cleanWikiPageTitle)
-- Remove href from links to non existant wiki page so they are not clickable :
-- <a href="/w/index.php?title=PageTitle&amp;action=edit&amp;redlink=1" class="new" title="PageTitle">PageTitle____on</a>
-- (removal of the href="" will make them non clickable)
html = html:gsub([[<a[^>]* class="new"[^>]*>]], [[<a class="newwikinonexistent">]])
-- Fix some other protocol-less links to wikipedia (href="//fr.wikipedia.org/w/index.php..)
html = html:gsub([[href="//]], [[href="https://]])
-- crengine does not return link if multiple class names in <a> (<a class="external text" href="">)
-- it would be no problem as we can't follow them, but when the user tap
-- on it, the tap is propagated to other widgets and page change happen...
-- html = html:gsub([[<a rel="nofollow" class="external text"]], [[<a rel="nofollow" class="externaltext"]])
-- html = html:gsub([[<a class="external text"]], [[<a class="externaltext"]])
-- Solved by our multiple class names suppression above
-- Avoid link being clickable before <a> (if it starts a line) or after </a> (if it
-- ends a line or a block) by wrapping it with U+200B ZERO WIDTH SPACE which will
-- make the DOM tree walking code to find a link stop at it.
-- html = html:gsub("(<[aA])", "\xE2\x80\x8B%1")
-- html = html:gsub("(</[aA]>)", "%1\xE2\x80\x8B")
-- Fixed in crengine lvtinydom.
if self.wiki_prettify then
-- Prepend some symbols to section titles for a better visual feeling of hierarchy
html = html:gsub("<h1>", "<h1> "..h1_sym.." ")
html = html:gsub("<h2>", "<h2> "..h2_sym.." ")
html = html:gsub("<h3>", "<h3> "..h3_sym.." ")
html = html:gsub("<h4>", "<h4> "..h4_sym.." ")
html = html:gsub("<h5>", "<h5> "..h5_sym.." ")
html = html:gsub("<h6>", "<h6> "..h6_sym.." ")
end
-- Note: in all the gsub patterns above, we used lowercase for tags and attributes
-- because it's how they are in wikipedia HTML and it makes the pattern simple.
-- If one day this changes, they'll have to be replaced with href => [Hh][Rr][Ee][Ff] ...
-- We can finally build the final HTML with some header of our own
local saved_on = T(_("Saved on %1"), os.date("%b %d, %Y %H:%M:%S"))
local online_version_htmllink = string.format([[<a href="%s/wiki/%s">%s</a>]], wiki_base_url, page:gsub(" ", "_"), _("online version"))
local see_online_version = T(_("See %1 for up-to-date content"), online_version_htmllink)
epub:add("OEBPS/content.html", string.format([[
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>%s</title>
<link type="text/css" rel="stylesheet" href="stylesheet.css"/>
</head>
<body>
<h1 class="koreaderwikifrontpage">%s</h1>
<h5 class="koreaderwikifrontpage">Wikipedia %s</h5>
<p class="koreaderwikifrontpage">%s<br/>%s</p>
<hr class="koreaderwikifrontpage"/>
%s
</body>
</html>
]], page_cleaned, page_htmltitle, lang:upper(), saved_on, see_online_version, html))
-- Force a GC to free the memory we used till now (the second call may
-- help reclaim more memory).
collectgarbage()
collectgarbage()
-- ----------------------------------------------------------------
-- OEBPS/images/*
if include_images then
local nb_images = #images
for inum, img in ipairs(images) do
-- Process can be interrupted at this point between each image download
-- by tapping while the InfoMessage is displayed
-- We use the fast_refresh option from image #2 for a quicker download
local go_on = UI:info(T(_("Retrieving image %1 / %2 …"), inum, nb_images), inum >= 2)
if not go_on then
cancelled = true
break
end
local src = img.src
if use_img_2x and img.src2x then
src = img.src2x
end
logger.dbg("Getting img ", src)
local success, content = getUrlContent(src)
-- success, content = getUrlContent(src..".unexistant") -- to simulate failure
if success then
logger.dbg("success, size:", #content)
else
logger.info("failed fetching:", src)
end
if success then
-- Images do not need to be compressed, so spare some cpu cycles
local no_compression = true
if img.mimetype == "image/svg+xml" then -- except for SVG images (which are XML text)
no_compression = false
end
epub:add("OEBPS/"..img.imgpath, content, no_compression)
else
go_on = UI:confirm(T(_("Downloading image %1 failed. Continue anyway?"), inum), _("Stop"), _("Continue"))
if not go_on then
cancelled = true
break
end
end
end
end
-- Done with adding files
if cancelled then
if UI:confirm(_("Download did not complete.\nDo you want to create an EPUB with the already downloaded images?"), _("Don't create"), _("Create")) then
cancelled = false
end
end
if cancelled then
UI:info(_("Canceled. Cleaning up…"))
else
UI:info(_("Packing EPUB…"))
end
epub:close()
-- This was nearly a no-op, so sleep a bit to make that progress step seen
ffiutil.usleep(300000)
UI:reset() -- close last InfoMessage
if cancelled then
-- Build was cancelled, remove half created .epub
if lfs.attributes(epub_path_tmp, "mode") == "file" then
os.remove(epub_path_tmp)
end
return false
end
-- Finally move the .tmp to the final file
os.rename(epub_path_tmp, epub_path)
logger.info("successfully created:", epub_path)
-- Force a GC to free the memory we used (the second call may help
-- reclaim more memory).
collectgarbage()
collectgarbage()
return true
end
-- Wrap Wikipedia:createEpub() with UI progress info, provided
-- by Trapper module.
function Wikipedia:createEpubWithUI(epub_path, page, lang, result_callback)
-- To do any UI interaction while building the EPUB, we need
-- to use a coroutine, so that our code can be suspended while waiting
-- for user interaction, and resumed by UI widgets callbacks.
-- All this is hidden and done by Trapper with a simple API.
local Trapper = require("ui/trapper")
Trapper:wrap(function()
Trapper:setPausedText("Download paused")
-- If errors in Wikipedia:createEpub(), the coroutine (used by
-- Trapper) would just abort (no reader crash, no error logged).
-- So we use pcall to catch any errors, log it, and report
-- the failure via result_callback.
local ok, success = pcall(self.createEpub, self, epub_path, page, lang, true)
if ok and success then
result_callback(true)
else
Trapper:reset() -- close any last widget not cleaned if error
logger.warn("Wikipedia.createEpub pcall:", ok, success)
result_callback(false)
end
end)
end
return Wikipedia