#!/bin/sh

# Copyright (C) 2014 Karl Fogel under opensource.org/licenses/BSD-2-Clause

# Track one's progress in finishing TODO items recorded in Org Mode.
#
# Each run of this script compares my current Org Mode "TODO" items
# (including both "TODO" and "STARTED", but not "DONE") with those
# from 24 hours ago, and prints a summary of the difference, e.g.:
#
#   $ ~/bin/todo-trend
#   39  ->  33  (-6)
#
# In other words, a day ago I had 39 unfinished TODOs, now I have 33,
# and the difference is that the count went down by 6.  Progress!
#
# For this to work, your Org Mode files have to be under revision
# control (the script assumes Subversion, but it could as easily be
# Git or Mercurial or something else), and you'll need to tweak
# ORG_FILES below to refer to whatever variable in Emacs lists all the
# org files you care about for TODO purposes.  For most people,
# `org-agenda-files' would probably work.

# Try replacing `kf-org-files' with `org-agenda-files' below, and of
# course replace `kfogel' with your own username.  (You can't just get
# rid of the -u flag and its parameter, because then the --batch will
# imply -q and your .emacs won't get loaded at all.)
ORG_FILES=`emacs                                                      \
  --batch -u kfogel                                                   \
  --eval '(mapcar (lambda (x) (princ x) (princ "\n")) kf-org-files)'  \
  2>/dev/null`

TMP_DIR=${HOME}/private/scratch

TODO_RE="^\*+ (TODO|STARTED) "

# Get the total TODO count from 24 hours ago.
rm -f ${TMP_DIR}/todo-trend-tmp
for F in ${ORG_FILES}; do
  svn cat -r{"24 hours ago"} ${F} >> ${TMP_DIR}/todo-trend-tmp
done
THEN=`cat ${TMP_DIR}/todo-trend-tmp | grep -E "${TODO_RE}" | wc -l`
rm -f ${TMP_DIR}/todo-trend-tmp

# Get the total TODO count now.
NOW=`cat ${ORG_FILES} | grep -E "${TODO_RE}" | wc -l`

# Compare.
echo "${THEN}  ->  ${NOW}  (`dc -e \"${NOW} ${THEN} - p\"`)"