Module:British regnal year

-- This module implements. It converts a year in the Gregorian -- calendar to the equivalent English or British regnal year.

local data = mw.loadData( 'Module:British regnal year/data' )

local p = {}

function p.main( frame ) -- If we are being called from #invoke, then the year is the first positional -- argument. If not, it is the frame parameter. local inputYear if frame == mw.getCurrentFrame then inputYear = frame:getParent.args[ 1 ] local frameArgsYear = frame.args[ 1 ] if frameArgsYear then inputYear = frameArgsYear end else inputYear = frame end

-- Convert the input to an integer if possible. Return "N/A" if the input could -- not be converted, or if the converted input is too big or too small. if type( inputYear ) ~= 'number' then inputYear = tonumber( inputYear ) end if not inputYear then return "N/A" end local currentYear = tonumber( mw.language.getContentLanguage:formatDate( 'Y' ) ) -- The year 1066 is significant because it is when the Norman conquest of England occurred. if inputYear < 1066 or inputYear > currentYear then return "N/A" end -- Find the year in the data page and display the output. for _, t in ipairs( data ) do       local dataYear = t.year if inputYear >= dataYear then -- Get data values from the data page. local startYear = t.startYear local currentRegnalYear = inputYear - dataYear + startYear local linkCurrent = t.linkCurrent local prevEndYear = t.prevEndYear local linkPrev = t.linkPrev local note = t.note

if inputYear > dataYear then -- Years with the same monarch. return mw.ustring.format(                   '%d %s – %d %s%s',                    currentRegnalYear - 1, linkCurrent, currentRegnalYear, linkCurrent, note or ''                ) elseif inputYear == dataYear and prevEndYear and linkPrev then -- Years with a different monarch. return mw.ustring.format(                   '%d %s – %d %s%s',                    prevEndYear, linkPrev, currentRegnalYear, linkCurrent, note or ''                ) else -- This should only match the year 1066. return mw.ustring.format(                   '%d %s%s',                    currentRegnalYear, linkCurrent, note or ''                ) end end end end

return p