#!/usr/bin/python3

""" Maintenance up the database used by dirnotes and c_dirnotes
- view the history of file comments
- delete the history of file comments
"""

import sqlite3, os, sys
import logging
VERSION = "0.1"

dbname = "~/.dirnotes.db"
dbname = os.path.expanduser(dbname)

def main(summary, view, delete):
  try:
    d = sqlite3.connect(dbname)
  except sqlite3.OperationalError:
    print("database not found, or permission-locked; cleanup aborted")
    return
  c = d.cursor()
  if summary:
    c = d.cursor()
    total,distinct = c.execute("select count(name),count(distinct name) from dirnotes;").fetchone()
    print(f"this database has entries for {distinct} files, and {total-distinct} history entries")

  if view or delete:
    c.execute("select distinct name from dirnotes;")
    for f in c:
      # note, f is a tuple of (name,)
      c1 = d.cursor()
      if view:
        history = c1.execute("select comment_date,author,comment from dirnotes where name=? order by comment_date desc",f).fetchall()
        if len(history)>1:
          print(f"filename: {f[0]} has a history of comments:")
          first = True
          for lin in history:
            print(f"{'->' if first else '  '}  date: {lin[0]} author: {lin[1]}\n    comment: {lin[2]}")
            first = False

      if delete:
        most_recent = c1.execute("select comment_date from dirnotes where name=? order by comment_date desc",f).fetchone()[0]
        logging.info(f"working on file: {f} with most-recent-date of {most_recent}")
        c1.execute("delete from dirnotes where name=? and comment_date <> ?",(f[0],most_recent))

  if delete:
    total,distinct = c.execute("select count(name),count(distinct name) from dirnotes;").fetchone()
    print(f"this database has been cleaned to {distinct} files, and {total-distinct} history entries")
    d.commit()
  d.close()


view = False
delete = False
summary = True  # default

if __name__ == "__main__":
  logging.basicConfig(filename="/tmp/dirnotes_clear.log", level=logging.DEBUG)
  logging.info("starting the db mainenance tool")
  if len(sys.argv)>1:
    if "-h" in sys.argv or "--help" in sys.argv:
      print(f"Usage: {sys.argv[0]}    maintenance for the database used by dirnotes & c_dirnotes")
      print("      -d     delete comment history")
      print("      -s     view comment summary")
      print("      -v     view comment history")
      sys.exit(1)
    if "-v" in sys.argv:
      view = True
    if "-s" in sys.argv:
      summary = True
    if "-d" in sys.argv:
      delete = True
  if delete:
    print("Cleanup of the dirnotes database located at ~/.dirnotes.db")
    c = input("Proceed? (Y/N)")
    if c in ("yY"):
      main(summary, view, delete)
    else:
      print("nothing done")
  else:
    main(summary, view, delete)