Rename A Bunch Of Files By Constructing mv Commands

I downloaded a bunch of bank statements as PDFs. On the upside they all were consistently named. On the downside they used an unhelpful date format. With a date format that puts year before month before day, the files easily sort alphanumerically. However, these filenames used a date format that put month before day before year.

Here is a subset of the files

$ ls *.pdf
'012524 Statement.pdf'
'012725 Statement.pdf'
'022624 Statement.pdf'
'022625 Statement.pdf'
'032524 Statement.pdf'
'032525 Statement.pdf'

Notice they are named with MMDDYY Statement.pdf. I would instead like for them to be named as YYYY-MM-DD-statement.pdf.

I can generate a series of mv statements that then get piped to sh which evaluates them. But first, let's do a dry run of a sed statement that rearranges the date parts.

$ ls *.pdf | sed 's/\(..\)\(..\)\(..\) Statement\.pdf/mv "&" "20\3-\1-\2-statement.pdf"/'
mv "012524 Statement.pdf" "2024-01-25-statement.pdf"
mv "012725 Statement.pdf" "2025-01-27-statement.pdf"
mv "022624 Statement.pdf" "2024-02-26-statement.pdf"
mv "022625 Statement.pdf" "2025-02-26-statement.pdf"
mv "032524 Statement.pdf" "2024-03-25-statement.pdf"
mv "032525 Statement.pdf" "2025-03-25-statement.pdf"

The way this works is that all the pdf files in the current directly get listed out. That gets piped to a sed statement that matches on capture groups against the first three pairs of characters (the date parts) in the filenames. It matches on the rest of the filename (Statement.pdf). This is then replaced by a mv, the full match of the original filename (&), and then the new filename made up of the rearranged date parts.

I can then pipe it to sh to run those mv commands.

$ ls *.pdf |
  sed 's/\(..\)\(..\)\(..\) Statement\.pdf/mv "&" "20\3-\1-\2-statement.pdf"/' |
  sh