Module:File

-- Module for handling Media files (Origin: Wikimedia Commons)

require('strict')

-- ==================================================
-- === helper Lookup table ==========================
-- ==================================================

local extensionMap = {
	-- File types with full support in Commons (See [[c:Commons:File types]]).
	DJVU = 'image/vnd.djvu',
	FLAC = 'audio/x-flac',
	GIF  = 'image/gif',
	JPEG = 'image/jpeg',
	JPG  = 'image/jpeg',
	MID  = 'audio/midi',
	MP3  = 'audio/mpeg',
	OGA  = 'audio/ogg',
	OGG  = 'audio/ogg',
	OGV  = 'video/ogg',
	PDF  = 'application/pdf',
	PNG  = 'image/png',
	SVG  = 'image/svg+xml',
	TIF  = 'image/tiff',
	TIFF = 'image/tiff',
	WEBM = 'video/webm',
	WEBP = 'image/webp',
	WAV  = 'audio/x-wav',
	XCF  = 'image/xcf',

	-- Other file types with restrictions (not accepted in standard uploads on Commons but in 'User:' namespace).
	-- They could be supported in Wiki pages by embedding their content in an <pre> or <source> elements.
	CSS  = 'text/css',
	CSV  = 'text/csv',
	JS   = 'application/javascript',
	JSON = 'application/json',
	TXT  = 'text/plain',
	XML  = 'application/xml',

	-- Only generated by MediaWiki on output of some queries, restricted in all uploads.
	GZ   = 'application/gzip', -- delivered only only for some wiki results
	ZIP  = 'application/zip', -- delivered only for some wiki data exports

	-- Other file types not supported and to convert (a few of them may be in special administration namespaces).
	DOC  = 'application/msword', -- please convert to PDF, DJVU, or Wiki
	F4V  = 'video/mpeg', -- (deprecated, replaced by MP4) please convert to OGV or WEBM
	FLV  = 'video/x-flv', -- (deprecated, replaced by MP4) please convert to OGV or WEBM
	ICO  = 'image/vnd.microsoft.icon', -- used in MediaWiki resources for 'website icons'
	MP4  = 'video/mp4', 
	QT   = 'video/quicktime', -- (deprecated, replaced by MP4) please convert to OGV or WEBM
	RA   = 'audio/vnd.rn-realaudio', -- (deprecated, replaced by MP3) please convert to OGA
	SWF  = 'video/x-flv', -- (deprecated, replaced by MP4) please convert to OGV or WEBM
	WMA  = 'audio/x-ms-wma', -- please convert to OGA
	WMV  = 'video/x-ms-wmv', -- please convert to OGV or WEBM
	XLS  = 'application/vnd.ms-excel', -- please convert to PDF, DJVU, or Wiki
}

-- ==================================================
-- === Local functions ==============================
-- ==================================================

local function filename(frame)
	return frame.args[1] or frame.args["file"] or frame.args["title"] 
end

local function getMetadata(frame)
	local fname = filename(frame)
	local title
	if fname then
        title = mw.title.new(fname, 6)
	else
        title = mw.title.getCurrentTitle()
	end
	if title then
		return title.file
	else
		return {exists=false}
	end
end

-- ==================================================
-- === External functions ===========================
-- ==================================================
local p = {}

-- p.csExtension("Foo.bar.svg")
-- @return "svg"
function p.csExtension(frame)
	local fname = filename(frame) or mw.title.getCurrentTitle().text
	local parts = mw.text.split(fname, '.', true)
	if #parts>1 then
		return parts[#parts]
	else
		return ''
	end
end

function p.extension(frame)
	return p.csExtension(frame):lower()
end

function p.extensionUpper(frame)
	return p.csExtension(frame):upper()
end

-- p.woExtension("Foo.bar.svg")
-- @return "Foo.bar"
-- Original author: Bawolff at [[Module:FileName]]
function p.woExtension(frame)
	local fname = filename(frame) or mw.title.getCurrentTitle().text
	local parts = mw.text.split(fname , '.', true)
	local upTo = #parts - 1
	if upTo == 0 then upTo = 1 end
	return table.concat(parts, '.', 1, upTo)
end

function p.mime(frame)
	local meta  = getMetadata(frame)
	if meta.exists then
		return meta.mimeType
	else
		return extensionMap[p.extensionUpper(frame)] or 'unknown'
	end
end 

function p.mimeType(frame)
	return getMetadata(frame).mimeType
end

function p.fileExists(frame)
	return getMetadata(frame).exists or ''
end

-- This one won't throw errors at you
function p.fileExistsRelaxed(frame)
	local ok, metadata = pcall(getMetadata(frame))
	if ok then
		return metadata.exists or ''
	else
		return ''
	end
end

function p.maxthumb(frame)
-- Limits in megapixels are currently stored in Commons templates, they could be in this module.
-- There may be more limits for other supported mime types (djvu, flac, ogv, pdf, svg, webm, xcf).
	local maxthumbMap = {
		['image/gif']  = 1000, 
		['image/png' ] = 2500, -- see Template:LargePNG/limit
		['image/tiff'] = 1000, -- see Template:LargeTIFF/limit
	}
	local mime = p.mime(frame)
	return maxthumbMap[mime] or 'unknown @Module:File'
end

function p.dateWorkCreated(frame)
	return '' -- no longer supported
end

function p.width(frame)
	return getMetadata(frame).width
end

function p.height(frame)
	return getMetadata(frame).height
end

function p.dimensions(frame)
	local d = getMetadata(frame)
	if d.exists then
		return d.width .. ' × ' .. d.height  
	else
		return ''
	end
end

function p.size(frame)
	return getMetadata(frame).size
end

function p.pageCount(frame)
	local pages = getMetadata(frame).pages or {1}
	return #pages
end

return p