Module:Calendar date explained

--

require('strict')

local p = local cfg -- Data structure from ~/eventslocal eventdata -- Data structure from ~/localfiles/local track = -- Tracking category container

----------------------------< inlineError >-----------------------

Critical error. Render output completely in red. Add to tracking category.

local function inlineError(arg, msg, tname)

track["Category:Calendar date template errors"] = 1 return '

Error in - Check |' .. arg .. '= ' .. msg .. ''

end

----------------------------< trimArg >-----------------------

trimArg returns nil if arg is "" while trimArg2 returns 'true' if arg is "" trimArg2 is for args that might accept an empty value, as an on/off switch like nolink=

local function trimArg(arg) if arg

"" or arg

nil then return nil end return mw.text.trim(arg)endlocal function trimArg2(arg) if arg

nil then return nil end return mw.text.trim(arg)end

----------------------------< tableLength >-----------------------

Given a 1-D table, return number of elements

local function tableLength(T) local count = 0 for _ in pairs(T) do count = count + 1 end return countend

--D] ]; if only link is provided, returns a wikilink in the form [[L] ]; if neither are provided or link is omitted, returns an empty string.

local function make_wikilink (link, display, no_link) if nil

no_link then if link and ( ~= link) then if display and ( ~= display) then return table.concat ; end return table.concat ; end else -- no_link if display and ( ~= display) then -- if there is display text return display; -- return that end return link or ; -- return the target article name or empty string endend

----------------------------< createTracking >-----------------------

Return data in track[] ie. tracking categories

local function createTracking

local out = ; if tableLength(track) > 0 then for key, _ in pairs(track) do -- loop through table table.insert (out, make_wikilink (key)) -- and convert category names to links end end return table.concat (out) -- concat into one big string; empty string if table is emptyend

----------------------------< isValidDate >----------------------------------------------------

Returns true if date is after 31 December 1899, not after 2100, and represents a valid date (29 February 2017 is not a valid date). Applies Gregorian leapyear rules. All arguments are required.

local function isValidDate (year, month, day)

local days_in_month = local month_length local y, m, d local today = os.date ('*') -- fetch a table of current date parts

if not year or year

or not month or month

or not day or day

then return false -- something missing end

y = tonumber (year) m = tonumber (month) d = tonumber (day)

if 1900 > y or 2100 < y or 1 > m or 12 < m then -- year and month are within bounds return false end

if (2

m) then -- if February month_length = 28 -- then 28 days unless if (0

(y%4) and (0~=(y%100) or 0

(y%400))) then -- is a leap year? month_length = 29 -- if leap year then 29 days in February end else month_length=days_in_month[m]; end

if 1 > d or month_length < d then -- day is within bounds return false end return trueend

----------------------------< makeDate >-----------------------

Given a zero-padded 4-digit year, 2-digit month and 2-digit day, return a full date in df format df = mdy, dmy, iso, ymd

local function makeDate(year, month, day, df, format) local formatFull = local formatInfobox =

if not year or year

"" or not month or month

"" or not day or day

"" and format[df] then return nil end

local date = table.concat -- assemble iso format date if format ~= "infobox" then return mw.getContentLanguage:formatDate (formatFull[df], date) end return mw.getContentLanguage:formatDate (formatInfobox[df], date)end

----------------------------< dateOffset >-----------------------

Given a 'origdate' in ISO format, return the date offset by number of days in 'offset' eg. given "2018-02-01" and "-1" it will return "2018-01-30" On error, return origdate

local function dateOffset(origdate, offset)

local year, month, day = origdate:match ('(%d%d%d%d)-(%d%d)-(%d%d)') local now = os.time local newdate = os.date("%Y-%m-%d", now + (tonumber(offset) * 24 * 3600)) return newdate and newdate or origdate

end

----------------------------< renderHoli >-----------------------

Render the data

local function renderHoli(cfg,eventdata,calcdate,date,df,format,tname,cite)

local hits = 0 local matchdate = "^" .. date local startdate,enddate,outoffset,endoutoffset = nil local starttitle,endtitle = ""

-- user-supplied date calculator if cfg.datatype

"calculator" then if cfg.datasource then startdate = calcdate enddate = dateOffset(startdate, cfg.days - 1) else return inlineError("holiday", 'invalid calculator result', tname) end

-- read dates from localfile -- it assumes dates are in chrono order, need a more flexible method elseif cfg.datatype

"localfile" then local numRecords = tableLength(eventdata) -- Get first and last date of holiday for i = 1, numRecords do if mw.ustring.find(eventdata[i].date, matchdate) then if hits

0 then startdate = eventdata[i].date hits = 1 end if hits >= tonumber(cfg.days) then enddate = eventdata[i].date break end hits = hits + 1 end end end -- Verify data and special conditions if startdate

nil or enddate

nil then if cfg.name

"Hanukkah" and startdate and not enddate then -- Hanukkah bug, template doesn't support cross-year boundary enddate = dateOffset(startdate, 8) elseif cfg.datatype

"localfile" and cfg.days > "1" and startdate then enddate = dateOffset(startdate, cfg.days - 1) elseif startdate and not enddate then return inlineError("year", 'cannot find enddate', tname) .. createTracking else return inlineError("holiday", 'cannot find startdate and enddate', tname) .. createTracking end end -- Generate start-date offset (ie. holiday starts the evening before the given date) if cfg.startoffset then startdate = dateOffset(startdate, cfg.startoffset) if startdate ~= enddate then enddate = dateOffset(enddate, cfg.startoffset) else cfg.days = (cfg.days

"1") and "2" end end -- Generate end-date outside-Irael offset (ie. outside Israel the holiday ends +1 day later) endoutoffset = cfg.endoutoffset and dateOffset(enddate, cfg.endoutoffset)

-- Format dates into df format local year, month, day = startdate:match ('(%d%d%d%d)-(%d%d)-(%d%d)') startdate = makeDate(year, month, day, df, format) year, month, day = enddate:match ('(%d%d%d%d)-(%d%d)-(%d%d)') enddate = makeDate(year, month, day, df, format) if startdate

nil or enddate

nil then return nil end

-- Add "outside of Israel" notices if endoutoffset then year, month, day = endoutoffset:match ('(%d%d%d%d)-(%d%d)-(%d%d)') local leader = ((format

"infobox") and "
") or " " endoutoffset = leader .. "(" .. makeDate(year, month, day, df, "infobox") .. " outside of Israel)" end if not endoutoffset then endoutoffset = "" end

--- Determine format string format = ((format

"infobox") and " –
") or " – "

--- Determine pre-pended text string eg. "sunset, " local prepend1 = (cfg.prepend1 and (cfg.prepend1 .. ", ")) or "" local prepend2 = (cfg.prepend2 and (cfg.prepend2 .. ", ")) or ""

-- return output if startdate

enddate or cfg.days

"1" then -- single date return prepend1 .. startdate .. endoutoffset .. cite end return prepend1 .. startdate .. format .. prepend2 .. enddate .. endoutoffset .. citeend

----------------------------< calendardate >-----------------------

Main function

function p.calendardate(frame)

local pframe = frame:getParent local args = pframe.args

local tname = "Calendar date" -- name of calling template. Change if template rename. local holiday = nil -- name of holiday local date = nil -- date of holiday (year) local df = nil -- date format (mdy, dmy, iso - default: iso) local format = nil -- template display format options local cite = nil -- leave a citation at end local calcdate = ""

--- Determine holiday holiday = trimArg(args.holiday) -- required if not holiday then holiday = trimArg(args.event) -- event alias if not holiday then return inlineError("holiday", 'missing holiday argument', tname) .. createTracking end end

--- Determine date date = trimArg(args.year) -- required if not date then return inlineError("year", 'missing year argument', tname) .. createTracking elseif not isValidDate(date, "01", "01") then return inlineError("year", 'invalid year', tname) .. createTracking end

--- Determine format type format = trimArg(args.format) if not format or format ~= "infobox" then format = "none" end

-- Load configuration file local eventsfile = mw.loadData ('Module:Calendar date/events') if eventsfile.hebrew_calendar[mw.ustring.upper(holiday)] then cfg = eventsfile.hebrew_calendar[mw.ustring.upper(holiday)] elseif eventsfile.christian_events[mw.ustring.upper(holiday)] then cfg = eventsfile.christian_events[mw.ustring.upper(holiday)] elseif eventsfile.carnivals[mw.ustring.upper(holiday)] then cfg = eventsfile.carnivals[mw.ustring.upper(holiday)] elseif eventsfile.chinese_events[mw.ustring.upper(holiday)] then cfg = eventsfile.chinese_events[mw.ustring.upper(holiday)] elseif eventsfile.misc_events[mw.ustring.upper(holiday)] then cfg = eventsfile.misc_events[mw.ustring.upper(holiday)] else return inlineError("holiday", 'unknown holiday ' .. holiday, tname) .. createTracking end

-- If datatype = localfile if cfg.datatype

"localfile" then local eventfile = nil eventfile = mw.loadData(cfg.datasource) if eventfile.event then eventdata = eventfile.event else return inlineError("holiday", 'unknown holiday file ' .. cfg.datasource .. '', tname) .. createTracking end

-- If datatype = calculator elseif cfg.datatype

"calculator" then calcdate = frame:preprocess(cfg.datasource:gsub("YYYY", date)) local year, month, day = calcdate:match ('(%d%d%d%d)-(%d%d)-(%d%d)') if not isValidDate(year, month, day) then return inlineError("holiday", 'invalid calculated date ' .. calcdate, tname) .. createTracking end else return inlineError("holiday", 'unknown "datatype" in configuration', tname) .. createTracking end

--- Determine df - priority to |df in template, otherwise df in datafile, otherwise default to dmy df = trimArg(args.df) if not df then df = (cfg.df and cfg.df) or "dmy" end if df ~= "mdy" and df ~= "dmy" and df ~= "iso" then df = "dmy" end

-- Determine citation cite = trimArg2(args.cite) if cite then if (cite ~= "no") then cite = "" if cfg.citeurl and cfg.accessdate and cfg.source and cfg.name then local citetitle = cfg.citetitle if citetitle

nil then citetitle = 'Dates for ' .. cfg.name end cite = frame:preprocess('^[1] ') elseif cfg.source then cite = frame:preprocess('^[2] ') end else cite = "" end else cite = "" end

-- Render local rend = renderHoli(cfg,eventdata,calcdate,date,df,format,tname,cite) if not rend then rend = '

Error in : Unknown problem. Please report on template talk page.' track["Category:Webarchive template errors"] = 1 end

return rend .. createTracking

end

return p

Notes and References

1. Web site: [' .. cfg.citeurl .. ' ' .. citetitle .. ' ]. ' .. cfg.source .. '. ' .. cfg.accessdate .. '.
2. ' .. cfg.source:gsub("YYYY", date) .. '