#!/bin/sh

# Offer to run a complex command from among those listed in specific files:
# ./.frequents and ~/.frequents.

# If there is an argument, it's taken as the line number to choose.
# Otherwise, user is presented with a consolidated list and prompted for
# line number of their choice.  In either case the choice is echoed and the
# command line is evalled.  (Using eval means the command line can contain
# multiple commands in a pipeline, sequence, and with backgrounded
# components.)  Oh, yeah - it skips lines that begin with a "#" hash mark.

# klm  August, 2007

unset lines

arg="$1"

read_from () {
  if [ -r "$1" ]; then
    exec 3< "$1"
    while read curline <&3; do
      if [ -z "$curline" -o "${curline:0:1}" = "#" ]; then continue; fi
      lines[${#lines[@]}]="$curline"
    done
    exec 3<&-
  fi
}

if [ ! .frequents -ef ~/.frequents ]; then
  read_from .frequents
fi
read_from ~/.frequents

incr=0
size=${#lines[@]}

if [ "$size" = 0 ]; then
  echo "no entries"
  exit
fi

if [ -n "$arg" ]; then
  which="$arg"
  echo -n "$arg "
else
  echo
  for i in "${lines[@]}"; do
    echo $((incr++)): $i
  done
  echo
  echo -n "execute command from line number[default=0, q to cancel]: "
  read which
fi

if [ -z "$which" ]; then
  which=0
fi

case "$which" in
  [0-9] | [0-9][0-9] | [0-9][0-9][0-9]) : ;;
  * ) echo cancelled
      exit;;
esac

if [ -z "${lines[$which]}" ]; then
   echo no match
   exit 1
else
   echo ":${lines[$which]}:"
   eval "${lines[$which]}"
fi