Custom function to add consecutive dates

[Mirodin]

I want to leverage a custom function to use a text file as a calendar.txt. Therefore when having the file open in Textadept I would like to open the command prompt (ctrl+E) and run i.e. addWeek.

2023-01-08 w01 Sun
2023-01-07 w01 Sat
2023-01-06 w01 Fri
...

Would become this:

2023-01-15 w02 Sun
2023-01-14 w02 Sat
2023-01-13 w02 Fri
2023-01-12 w02 Thu
2023-01-11 w02 Wed
2023-01-10 w02 Tue
2023-01-09 w02 Mon
2023-01-08 w01 Sun
2023-01-07 w01 Sat
2023-01-06 w01 Fri
...

This is what I have so far I am just missing the "find the last date" part.

function addWeek()
	local lastDate = -- get last date i.e. 2023-01-01
	local year, month, day = string.match(lastDate, "(%d+)-(%d+)-(%d+)")
	local date = { year = year, month = month, day = day }
	local tmp = {}
	for i = 1, 7 do
		date.day = date.day + 1
		local ts = os.time(date)
		date = os.date("*t", ts)
		tmp[#tmp + 1] = os.date("%Y-%m-%d w%W %a", ts)
	end
	buffer.document_start()
	buffer.add_text(table.concat(tmp, "\n") .. "\n")
end

Thanks in advance :)

[orbitalquark]

If your most recent week is at the top, then maybe something like this: local year, month, day, week = buffer:get_line(1):match('(%d+)%-(%d+)%-(%d+)') if not year then return end local lastDate = os.time{year = year, month = month, day = day} local date = os.date('*t', lastDate) ...

[Mirodin]

Thank you, works like a charm :)