#!/bin/sh
# clikan.sh -- CLI Kanban
ver='2021-01-23/HB9KNS'

conf="${CLIKANCONF:-$HOME/.clikanconf}"
defkanban="$HOME/clikanban.md"
editor="${CLIKANEDIT:-$VISUAL}"
editor="${editor:-$EDITOR}"
editor="${editor:-ed}"
myshell='/bin/sh -c'
filtr='.'

buff=`mktemp -t clikanbXXXXXX` || buff=${TMPDIR:-/tmp}/clikanb$$`date +%S%M%d`
self=`mktemp -t clikantXXXXXX` || self=${TMPDIR:-/tmp}/clikant$$`date +%S%M%d`
chmod 600 $self $buff
: >$self

if test ! -f "$conf"
then cat <<EOT
 no config found, generating default config file $conf
 and default kanban file $defkanban
 (this should happen only once at first use)
EOT
 cat <<EOT >"$conf"
# configuration file for $0
# (autogenerated at `date`)
# file name can be defined by env.var CLIKANCONF
#
#  prompt is displayed when waiting for command
prompt |<
#  maxshow defines the maximum number of cards/lines to be displayed
maxshow 15
#  sortdir defines order of non-calendar kanban cards
#  and can be one of up, down or none (default)
sortdir none
#  kanban defines a kanban file, may be given several times
# kanban /some/path/to/jobkanban.txt
# kanban /another/path/to/privatekanban.md
kanban $defkanban
EOT
 if test -f "$defkanban"
 then cp "$defkanban" "$defkanban.bak"
  echo found existing $defkanban,
  echo saved as backup $defkanban.bak
 fi
 cat <<EOT >"$defkanban"
# my kanban file

* learn to use clikan
- improve clikan
+ install clikan

### titles work as comments
# might be a future card you don't yet want in waiting
EOT
fi

# get lines beginning with a value, and remove that column
# note SPC&TAB in patterns: make sure there is a SPC,
#  and that the value is complete
getlines(){
 sed -e 's/$/	/' | grep "^$1[	 ]" | { while read _ values
# remove trailing added TAB
 do echo "${values%	}"
 done
 }
}

# display selection, and put selection list in selection file,
#  input through stdin, with lines prepended with index number, TAB and arg1
showselect(){
 local i
 i=1
 : >$self
 while read l
 do echo $i: $l
  echo "$i	$1$l" >>$self
  i=$(( $i+1 ))
 done
}

# get input from selection (showselect must be called before)
getselect(){
 if test "$1" != ""
 then echo "choice? (default: $1)" >&2
 else echo "choice?" >&2
 fi
 read i
 if test "$i" = ""
 then echo "$1"
 else getlines $i <$self
 fi
}

kbs="`getlines kanban <"$conf"`"
currkan="`echo "$kbs" | head -n 1`"
prompt=`getlines prompt <"$conf" | head -n 1`
maxshow=`getlines maxshow <"$conf" | head -n 1`
maxshow=${maxshow:-22}
sortdir=`getlines sortdir <"$conf" | head -n 1`
sortdir=${sortdir:-none}

showprompt(){
 if test "$prompt" != ""
 then printf '%s ' "$prompt"
 fi
}

# conditional sort
condsort(){
 case $sortdir in
 up) sort ;;
 down) sort -r ;;
 *) cat ;;
 esac
}

# display all 'something' cards
showall(){
 local f t ms
 ms=$maxshow
 case $1 in
 d*) f='*' ;;
 w*) f='-' ;;
# for archive/done, show a LOT of archived stuff
 a*) f='+' ; ms=99999 ;;
 *) f='' ;;
 esac
 echo
 echo "   $1 // `date`"
 if test "$filtr" != "."
 then echo "   ($filtr)"
 fi
 if test "$f" = "*"
 then t=`date +%m-%d`
# for "doing", sort filtered cards
  cat $kbs | grep -e $filtr | getlines "$f" | condsort
# and also display '- ...(MM-DD)...' calendar entries
  cat $kbs | grep "^[*+-] .*($t)" | sed -e 's/^. //'
# for waiting and archive, filter but keep saved card order
 else cat $kbs | grep -e $filtr | getlines "$f"
# for all cases, select the cards and show the beginning of the list
 fi | showselect "$f " | head -n $ms
}

# replace lines (in any kanban) containing some ed pattern
# arg.1=pattern, remainder=new line contents
repline(){
 local patt newl
 patt="$1"
 shift
 newl="$*"
 for ff in $kbs
 do cat "$ff" > $buff
  cat $buff | { while read oldl
  do if test "`echo \"$oldl\"`" = "$patt"
   then echo "$newl"
   else echo "$oldl"
   fi
  done
  } > "$ff"
 done
}

showhelp(){ cat <<EOH
$0 : command line kanban
  ($ver)
configuration file: $conf
for help about commands, just hit RETURN
to show configuration, enter 'c'
EOH
read k
case $k in
 c*) cat <<EOT
 CLIKANCONF=$CLIKANCONF
 configfile=$conf
 editor=$editor
 maxshow=$maxshow
 configfile contents:
EOT
  sed -e 's/^/    /' $conf
  ;;
 *) cat <<EOH
command keys:
 q: quit
 d/w/a: show 'doing/waiting(todo)/archive(done)' cards
 k: select target kanban for entry of new cards
 n: add new card to target kanban, separated by whitespace
    (e.g "n buy present!")
 done N: archive card N as done
 wait N: put card N back to waiting/todo state
 do N: put card N into doing state
    note: done/wait/do accept several arguments separated by white space
 f F: filter cards for grep pattern F (empty='.')
 ec: directly edit config file -- DANGER!
 ek: directly edit kanban file -- DANGER!
 !: execute arguments with "$myshell"
    note: if the command does not match to any of the
    internal $0 commands, and starts with a letter,
    you can even omit the leading exclamation mark!
EOH
  ;;
esac
}

showall doing
showprompt

while read com coa1 coa2 coa3 coar
do case $com in
q) break ;;
d) showall doing ;;
w) showall waiting/todo/backlog ;;
a) showall archived/done ;;
do|wait|done) if test "$coa1" = ""
  then echo "card number?"
   read coa1
  fi
  coar=`echo "$coa1 $coa2 $coa3 $coar" | sed -e 's/ *$/ /'`
  while test "$coar" != ""
  do
   coa1=`getlines ${coar%% *} <$self`
   stamp=''
   case $com in
   done) coa2='+'
    stamp=`date '+ // %y-%m-%d'`
    ;;
   wait) coa2='-' ;;
   *) coa2='*' ;;
   esac
   coa3=`echo "$coa1" | sed -e "s/^./$coa2/"`
   repline "$coa1" "$coa3$stamp"
   coar=${coar#* }
  done
  showall doing
  ;;
k) echo "$kbs" | showselect
  currkan=`getselect $currkan`
  showall doing
  ;;
n) newc=`echo "$coa1 $coa2 $coa3 $coar" | sed -e 's/ *$//'`
  if test "$newc" = ""
  then
   echo enter new card for target $currkan :
   read newc
  else echo adding card for target $currkan
  fi
  if test "$newc" != ""
  then echo '*' "$newc" >>$currkan
  else echo no content found, nothing added
  fi
  showall doing
  ;;
ec) echo calling "$editor $conf" ...
  "$editor" "$conf"
  echo please quit and restart to reload config ;;
ek) echo calling "$editor $currkan" ...
  "$editor" "$currkan" ;;
f) filtr="${coa1:-.}"
  echo "filtering for grep pattern '$filtr'" ;;
!*) echo
  $myshell "${com#!} $coa1 $coa2 $coa3 $coar"
  echo ;;
[A-Za-z]*) echo
  $myshell "$com $coa1 $coa2 $coa3 $coar"
  echo ;;
*) showhelp
  showall doing ;;
esac
showprompt
done

echo
rm -f $self $buff