Editing Module:Person date

require("strict")

local p = {}

local TEMPLATES = {
	birth_date = "Birth date",
	birth_date_and_age = "Birth date and age",
	birth_year = "Birth year",
	birth_year_and_age = "Birth year and age",
	death_date = "Death date",
	death_date_text = "Death date text",
	death_date_and_age = "Death date and age",
	death_year = "Death year",
	death_year_and_age = "Death year and age",
}
local invalid_date_category = ''
local tracking_category = ''
local Date = require('Module:Date')._Date
local getArgs = require('Module:Arguments').getArgs

if mw.title.getCurrentTitle():inNamespaces(0, 828, 829) then
	-- Category only in namespaces: 0=article, 828=module & 829=module talk (last 2 needed for testcases)
	tracking_category = '[[Category:Pages where birth or death is being automatically determined]]'
	invalid_date_category = '[[Category:Pages with invalid birth or death dates]]'
end

local function check_for_invalid_date(str)
	return mw.ustring.match(str, '^%?') or mw.ustring.match(str, '^%d%d%?') or mw.ustring.match(str, '^[Uu]nk')
end

local function expand_template(template, args)
	return mw.getCurrentFrame():expandTemplate{title = template, args = args}
end

local function parse_date(str)
	local date = Date(str)
	if date then
		return tostring(date.year), tostring(date.month), tostring(date.day)
	end
	-- TODO: Date has not been parsed. Need to work out what to do. For now, throw an error.
	-- Example where this can occur: "birth_date = 22 December 1946" at [[Maurice Pasternak]].
	-- There was a nonbreaking space after "22" whidh Date does not accept.
	error('Module:Person_date parse_date invalid date: "' .. tostring(str) .. '"')
end

local function date_format(str)
	if mw.ustring.match (str, '^%d+%s*%a+[%.]*%s*%d%d%d%d$') then
		return 'df'
	elseif mw.ustring.match(str, '^%a+[%.]*%s+%d+,%s*%d%d%d%d$') then
		return 'mf'
	else
		return 'ERROR'
	end

end

local function is_valid_month (str)
	str = string.upper(mw.ustring.sub(str,1,1))..string.lower(mw.ustring.sub(str,2))

	local months = {'Jan','Jan.','January','Feb','Feb.','February','Mar','March','Apr','Apr.','April','May','Jun','Jun.','June','Jul','Jul.','July','Aug','Aug.','August','Sep','Sept','Sep.','Sept.','September','Oct','Oct.','October','Nov','Nov','November','Dec','Dec.','December'}
	for index, value in ipairs(months) do
		if value == str then
			return true
		end
	end
	return false
end

local function is_month_year_only(str)
	local month = mw.ustring.match(str, '^(%a+)[%.]*%s+%d%d%d%d$')
	if month == nil then
		return false
	else
		return is_valid_month(month)
	end
end

local function is_valid_date(str)
	local month = mw.ustring.match (str, '^%d+%s*(%a+)[%.]*%s*%d%d%d%d$') or mw.ustring.match(str, '^(%a+)[%.]*%s+%d+,%s*%d%d%d%d$')
	if month == nil then
		return false
	else
		return is_valid_month(month)
	end
end

local function is_year_only(str)
	return mw.ustring.match(str, '^%d%d%d%d$')
end

local function already_has_template(str)
	str = mw.ustring.gsub(str, '&[Nn][Bb][Ss][Pp];', ' ')
	return mw.ustring.match(str, '<span') or mw.ustring.match(str, '<time') or mw.ustring.match(str,'%(aged%s*%d+') or mw.ustring.match(str,'%(age%s*%d+')
end

local function sanatize_date(str)
	-- Sanatize leading & trailing whitespace (this caused an issue before it was implemented)
	str = mw.ustring.gsub(str,'^%s*','')
	str = mw.ustring.gsub(str,'%s*$','')
	-- Sanatize ordinals
	str = mw.ustring.gsub(str, '(%d+)st([,%s])', '%1%2')
	str = mw.ustring.gsub(str, '(%d+)rd([,%s])', '%1%2')
	str = mw.ustring.gsub(str, '(%d+)th([,%s])', '%1%2')
	str = mw.ustring.gsub(str, '(%d+)nd([,%s])', '%1%2')
	return str
end

local function parse_birth(args)
	local birth_date = args['birth_date'] or ''
	local death_date = args['death_date'] or ''
	local disap_date = args['disappeared_date'] or ''
	local original = birth_date
	
	birth_date = sanatize_date(birth_date)
	death_date = sanatize_date(death_date)
	disap_date = sanatize_date(disap_date)

	-- Check for bad inputs. This used to be covered by a switch statement in infoboxes
	if check_for_invalid_date(birth_date) then
		return original..invalid_date_category
	end

	if already_has_template(birth_date) then
		return original
	end

	if is_valid_date(birth_date) then
		local location = mw.ustring.find(birth_date, '%d%d%d%d')
		local extra = mw.ustring.sub(birth_date, location+4) .. tracking_category
		local date = mw.ustring.sub(birth_date, 1,location+3)
		local year, month, day = parse_date(date)
		local format = date_format(date)
		if death_date == '' and disap_date == '' then
			return expand_template(TEMPLATES.birth_date_and_age, {year, month, day, [format] = 'yes'}) .. extra
		elseif is_year_only(death_date) or is_valid_date(death_date) or is_month_year_only(death_date) then
			return expand_template(TEMPLATES.birth_date, {year, month, day, [format] = 'yes'}) .. extra
		else
			-- death_date is not a valid string (example: 'unknown')
			return original
		end
	end
	if is_month_year_only(birth_date) then

		local year = Date('1 '..birth_date):text('%Y')
		local month = Date('1 '..birth_date):text('%-m')
		local location = mw.ustring.find(birth_date, '%d%d%d%d')
		local date = mw.ustring.sub(birth_date, 1,location+3)
		local extra = mw.ustring.sub(birth_date, location+4) .. tracking_category

		if death_date == '' and disap_date == '' then
			return expand_template(TEMPLATES.birth_year_and_age, {year, month}) .. extra
		elseif is_year_only(death_date) or is_valid_date(death_date) or is_month_year_only(death_date) then
			return expand_template(TEMPLATES.birth_year, {date}) .. extra
		else
			-- death_date is not a valid string (example: 'unknown')
			return original
		end

	end
	if is_year_only(birth_date) then
		local date = mw.ustring.sub(birth_date, 1, 5)
		local extra = mw.ustring.sub(birth_date, 5) .. tracking_category
		if death_date == '' and disap_date == '' then
			return expand_template(TEMPLATES.birth_year_and_age, {date}) .. extra
		elseif is_year_only(death_date) or is_valid_date(death_date) then
			return expand_template(TEMPLATES.birth_year, {date}) .. extra
		else
			-- death_date is not a valid string (example: 'unknown')
			return original
		end
	end

	return original
end

local function parse_death(args)
	local birth_date = args['birth_date'] or ''
	local death_date = args['death_date'] or ''
	local original = death_date

	birth_date = sanatize_date(birth_date)
	death_date = sanatize_date(death_date)

	-- Check for bad inputs. This used to be covered by a switch statement in infoboxes
	if check_for_invalid_date(death_date) then
		return original..invalid_date_category
	end

	if already_has_template(death_date) then
		return original
	end

	if is_valid_date(death_date) or is_month_year_only(death_date) then
		local location = mw.ustring.find(death_date, '%d%d%d%d')
		local date = mw.ustring.sub(death_date, 1,location+3)
		local extra = mw.ustring.sub(death_date, location+4) .. tracking_category
		local format = date_format(date)

		if birth_date == '' then
			if is_month_year_only(death_date) then
				return expand_template(TEMPLATES.death_date_text, {date}) .. extra
			end
			local year, month, day = parse_date(date)
			return expand_template(TEMPLATES.death_date, {year, month, day, [format] = 'yes'}) .. extra
		else
			if is_year_only(birth_date) then
				location =  mw.ustring.find(birth_date, '%d%d%d%d')
				local bd = mw.ustring.sub(birth_date, 1,location+3)
				if is_month_year_only(death_date) then
					return expand_template(TEMPLATES.death_date_and_age, {date, bd}) .. extra
				end

				return expand_template(TEMPLATES.death_date_and_age, {date, bd, [format] = 'yes'}) .. extra
			elseif is_valid_date(birth_date) or is_month_year_only(birth_date) then
				location =  mw.ustring.find(birth_date, '%d%d%d%d')
				local bd = mw.ustring.sub(birth_date, 1,location+3)

				if (is_month_year_only(death_date)) then
					return expand_template(TEMPLATES.death_date_and_age, {date, bd}) .. extra
				end

				return expand_template(TEMPLATES.death_date_and_age, {date, bd, [format] = 'yes'}) .. extra
			end
		end
	end

	if is_year_only(death_date) then
		if birth_date == '' then
			return  expand_template(TEMPLATES.death_year, {mw.ustring.sub(death_date, 1, 5)}) .. mw.ustring.sub(death_date, 5) .. tracking_category
		else
			if is_year_only(birth_date) then
				return  expand_template(TEMPLATES.death_year_and_age, {mw.ustring.sub(death_date, 1, 5), mw.ustring.sub(birth_date, 1, 5)}) .. mw.ustring.sub(death_date, 5) .. tracking_category
			else
				if is_valid_date(birth_date) then
					local location = mw.ustring.find(death_date, '%d%d%d%d')
					local date = mw.ustring.sub(death_date, 1,location+3)
					local extra = mw.ustring.sub(death_date, location+4) .. tracking_category

					location =  mw.ustring.find(birth_date, '%d%d%d%d')
					local bd = mw.ustring.sub(birth_date, 1,location+3)

					return  expand_template(TEMPLATES.death_date_and_age, {date, bd}) .. extra
				end
			end
		end
	end

	return original
end

function p.birth(frame)
	return parse_birth(getArgs(frame, {parentFirst = true}))
end

function p.death(frame)
	return parse_death(getArgs(frame, {parentFirst = true}))
end

return p