### -*-sh-*-
###
### Common per-shell configuration.

###--------------------------------------------------------------------------
### Utilities.

__mdw_programp () { type >/dev/null 2>&1 "$1"; }

__mdw_source_if_exists () {
  local i
  for i in "$@"; do
    if [ -r "$i" ]; then . "$i"; fi
  done
}

###--------------------------------------------------------------------------
### Hooks.

__mdw_addhook () {
  local hk=$1 fn=$2 t

  eval t=\${$hk+t}
  case $t in t) ;; *) echo >&2 "unknown hook \`$hk'"; return 2; esac

  eval t=\$$hk
  case " $t " in
    *" $fn "*) ;;
    *) eval "$hk=\${$hk:+\$$hk }\$fn" ;;
  esac
}

__mdw_delhook () {
  local hk=$1 fn=$2 t l r

  eval t=\${$hk+t}
  case $t in t) ;; *) echo >&2 "unknown hook \`$hk'"; return 2; esac

  eval t=\" \$$hk \"
  case $t in
    *" $fn "*)
      l=${t%% $fn*} r=${t##*$fn }
      l=${l# } r=${r% }
      eval "$hk=\$l\${l:+ }\$r"
      ;;
  esac
}

__mdw_setrc () { return $1; }

__mdw_runhook () {
  local hk=$1 saverc=$? t i; shift

  eval t=\${$hk+t}
  case $t in t) ;; *) echo >&2 "unknown hook \`$hk'"; return 2; esac

  eval t=\$$hk
  for i in $t; do __mdw_setrc $saverc; "$i" "$@"; done
}

###--------------------------------------------------------------------------
### Prompt machinery.

__mdw_host=$(hostname)
__mdw_hqual=
__mdw_hqual=$__mdw_hqual${SCHROOT_CHROOT_NAME+/$SCHROOT_CHROOT_NAME}
__mdw_hqual=$__mdw_hqual${CROSS_BUILDENV+/$CROSS_BUILDENV}
__mdw_set_prompt_hacks () { host=$__mdw_host; dir=""; }

__mdw_system=$(uname -s)
: ${USER-${LOGNAME-$(id -un)}}
__mdw_user=$USER

case $(id -u) in
  0)
    __mdw_rootp=t
    ;;
  *)
    case $__mdw_system in
      CYGWIN_*)
	case " $(id -G) " in
	  *" 544 "*) __mdw_rootp=t __mdw_user="$__mdw_user%admin" ;;
	  *) __mdw_rootp=nil ;;
	esac
	;;
      *)
	__mdw_rootp=nil
	;;
    esac
esac

__mdw_set_prompt_pieces () {

  ## Fancy highlighting in some terminals.
  local bold unbold nl more host dir
  local gitcolour extracolour rccolour uncolour
  bold="" unbold="" nl="" more=""
  gitcolour="" extracolour="" rccolour="" uncolour=""
  __mdw_set_prompt_hacks

  ## Choose the right delimiters.  Highlight root prompts specially;
  ## highlight when I'm running as some other user.  Highlight when this
  ## isn't the outermost shell on the terminal.
  local left right u tty
  case $__mdw_rootp in
    t)
      left=$(echo « | iconv -f UTF-8 -t //translit)
      right=$(echo » | iconv -f UTF-8 -t //translit)
      ;;
    nil)
      case $USER in
	mdw | mwooding | nemo) u="" left="[" right="]" ;;
	*) u="$__mdw_user@" left="{" right="}" ;;
      esac
      tty=$(tty)
      case "$__mdw_tty" in
	"$tty") left="<" right=">" ;;
	*) __mdw_tty=$tty; export __mdw_tty ;;
      esac
      ;;
  esac

  ## If this session is insecure then highlight that.
  local sec_l sec_r h
  h=$(hostname)
  case ${SSH_CLIENT-nil},${SCHROOT_CHROOT_NAME-nil},$__mdw_sechost in
    nil,nil,"$h") sec_l="" sec_r="" ;;
    nil,nil,*) sec_l="(" sec_r=")" ;;
    *) sec_l="" sec_r=""
  esac

  ## If this is an schroot environment or some other interesting augmented
  ## environment then point this out.

  ## Put together the main pieces.
  __mdw_prompt_left="$nl$bold$left$sec_l$u$host$__mdw_hqual$sec_r$dir"
  __mdw_prompt_git_left="$unbold$gitcolour"
  __mdw_prompt_git_right="$uncolour$bold"
  __mdw_prompt_rc_left="$unbold$rccolour"
  __mdw_prompt_rc_right="$uncolour$bold"
  __mdw_prompt_extra_left="$unbold$extracolour"
  __mdw_prompt_extra_right="$uncolour$bold"
  __mdw_prompt_right="$right$unbold"
  __mdw_prompt_more=" $more$bold>$unbold "
}

__mdw_set_prompt () {
  case "${TERM-dumb}:${INSIDE_EMACS+$INSIDE_EMACS}" in
    dumb:)
      case $(id -u) in 0) PS1='# ' ;; *) PS1='$ ' ;; esac
      PS2='> '
      ;;
    *)
      __mdw_last_rc=$?
      local git extra rc
      if type __git_ps1 >/dev/null 2>&1; then
	git="$__mdw_prompt_git_left$(__git_ps1)$__mdw_prompt_git_right"
      else
	git=""
      fi
      case $__mdw_last_rc in
	0) rc="" ;;
	*) rc="$__mdw_prompt_rc_left rc=$__mdw_last_rc$__mdw_prompt_rc_right" ;;
      esac
      case $__mdw_prompt_extra in
	?*) extra="$__mdw_prompt_extra_left [$__mdw_prompt_extra]$__mdw_prompt_extra_right" ;;
	*) extra="" ;;
      esac
      PS1="$__mdw_prompt_left$git$extra$rc$__mdw_prompt_right"
      PS2="$PS1$__mdw_prompt_more"
      unset __mdw_last_rc
      ;;
  esac
}

__mdw_xterm_settitle () {
  printf >/dev/tty \
    "]2;%s@%s:%s – %s\\" \
    "$__mdw_user" "$__mdw_host$__mdw_hqual" "$PWD" \
    "$1"
}
__mdw_xterm_precmd () { __mdw_xterm_settitle "$__mdw_shell"; }
__mdw_xterm_preexec () { __mdw_xterm_settitle "$1"; }

__mdw_screen_settitle () {
  printf >/dev/tty \
    "k%s\\" \
    "$1"
}
__mdw_screen_precmd () { __mdw_screen_settitle "$__mdw_shell"; }
__mdw_screen_preexec () { __mdw_screen_settitle "$1"; }

if [ -t 0 ]; then
  case ${STY+t},${__mdw_precmd_hook+t},${__mdw_preexec_hook+t},${TERM} in
    ,t,t,xterm*)
      __mdw_addhook __mdw_precmd_hook __mdw_xterm_precmd
      __mdw_addhook __mdw_preexec_hook __mdw_xterm_preexec
      ;;
    t,t,t,*)
      __mdw_addhook __mdw_precmd_hook __mdw_screen_precmd
      __mdw_addhook __mdw_preexec_hook __mdw_screen_preexec
      ;;
  esac
  case ${__mdw_precmd_hook+t} in
    t) __mdw_addhook __mdw_precmd_hook __mdw_set_prompt ;;
  esac
fi

###--------------------------------------------------------------------------
### Some handy aliases.

alias cx='chmod +x'
alias which="command -v"
alias rc="rc -l"
rootly () {
  case $# in 0) set -- "${SHELL-/bin/sh}" ;; esac
  $__MDW_ROOTLY "$@"
}
alias r=rootly
alias re="rootly $EDITOR"
alias pstree="pstree -hl"
alias cdtmp='cd ${TMPDIR-/tmp}'
alias pushtmp='pushd ${TMPDIR-/tmp}'
alias e="$EDITOR"
alias svn="svnwrap svn"
alias @="ssh"
alias make="nice make"
alias cross-run="nice cross-run"
alias gdb="gdb -q"

## Shut up Lisp interpreters.
alias clisp="clisp -q -q"
alias cmucl="rlwrap cmucl -quiet"
alias ecl="rlwrap ecl"
alias sbcl="rlwrap sbcl --noinform"
alias ccl="rlwrap ccl"
alias ccl32="rlwrap ccl32"
alias ccl64="rlwrap ccl64"
alias abcl="rlwrap abcl --noinform"

###--------------------------------------------------------------------------
### Colour output.

## Arrange for `ls' output to be in colour.
if __mdw_programp dircolors; then eval $(dircolors -b "$HOME/.dircolors")
else unset LS_COLORS; fi

unalias ls 2>/dev/null || :
ls () {
  if [ -t 1 ]; then command ls $LS_OPTIONS ${LS_COLORS+--color=auto} "$@"
  else command ls "$@"; fi
}

## Arrange for `grep' output to be in colour.
export GREP_COLORS="mt=01;31:ms=01;31:mc=031;31:fn=36:ln=36:bn=36:se=34"

greplike () {
  local grep=$1; shift
  if [ -t 1 ]; then
    command $grep ${GREP_COLORS+--color=always} "$@" | mdw-pager
  else
    command $grep "$@"
  fi
}
alias grep="greplike grep"
alias egrep="greplike egrep"
alias fgrep="greplike fgrep"
alias zgrep="greplike zgrep"

## Arrange for `diff' output to be in colour.
export DIFF_COLORS="hd=1:ln=36:ad=32:de=31"
difflike () {
  local diff=$1; shift
  if [ -t 1 ]; then
    command $diff \
	    ${DIFF_COLORS+--color=always} \
	    ${DIFF_COLORS+--palette="$DIFF_COLORS"} \
	    "$@" | mdw-pager
  else
    command $diff "$@" | cat
  fi
}
alias diff="difflike diff"

###--------------------------------------------------------------------------
### Other hacks.

## Turn off pagers inside Emacs shell buffers.
case "$INSIDE_EMACS" in
  2[2-9].*,comint | [3-9][0-9].*,comint) export PAGER=cat ;;
esac

###--------------------------------------------------------------------------
### More complicated shell functions.

## xt [@HOST] XTERM-ARGS
##
## Open a terminal, maybe on a remote host.
xt () {
  case "$1" in
    @*)
      local remote=${1#@} title
      shift
      if [ $# -gt 0 ]; then
	title="xterm [$remote] $1"
      else
	title="xterm [$remote]"
      fi
      (xterm -title "$title" -e ssh $remote "$@" &)
      ;;
    *)
      (xterm "$@" &)
      ;;
  esac
}

## core [y|n]
##
## Tweak core dumps on and off, or show the current status.
core () {
  case "x$1" in
    xon|xy|xyes) ulimit -Sc $(ulimit -Hc) ;;
    xoff|xn|xno) ulimit -Sc 0 ;;
    x)
      local l=$(ulimit -Sc)
      case $l in
	0) echo "Core dumps disabled" ;;
	unlimited) echo "Core dumps enabled" ;;
	*) echo "Core dump limit is $l blocks" ;;
      esac
      ;;
    *)
      echo >&2 "usage: core [y|n]"
      return 1
      ;;
  esac
}

## world [NAME]
##
## Set current security world to NAME.  With no NAME, print the currently
## selected world.
world () {
  local nfast=${NFAST_HOME-/opt/nfast}
  local kmdata
  case "$#" in
    0)
      echo "${NFAST_KMDATA#$nfast/kmdata-}"
      ;;
    *)
      if [ -d "$1" ]; then
	kmdata=$1
      elif [ -d "$nfast/kmdata-$1" ]; then
	kmdata=$nfast/kmdata-$1
      else
	echo >&2 "world: can't find world $1"
	return 1
      fi
      shift
      case "$#" in
	0) export NFAST_KMDATA=$kmdata ;;
	*) "$@" ;;
      esac
      ;;
  esac
}

## path-add [VAR] DIR
##
## Add DIR to the beginning of PATH-like variable VAR (defaults to PATH) if
## it's not there already.
path_add () {
  local pathvar export dir val
  case $# in
    1) pathvar=PATH dir=$1 export="export PATH" ;;
    2) pathvar=$1 dir=$2 export=: ;;
    *) echo >&2 "Usage: $0 [VAR] DIR"; return 1 ;;
  esac
  eval val=\$$pathvar
  case ":$val:" in
    *:"$dir":*) ;;
    *) val=$dir:$val ;;
  esac
  eval $pathvar=\$val
  eval $export
}

## path-remove [VAR] DIR
##
## Remove DIR from PATH-like variable VAR (defaults to PATH); it's not an
## error if DIR isn't in VAR.
path_remove () {
  local pathvar export dir val
  case $# in
    1) pathvar=PATH dir=$1 export="export PATH" ;;
    2) pathvar=$1 dir=$2 export=: ;;
    *) echo >&2 "Usage: $0 [VAR] DIR"; return 1 ;;
  esac
  eval val=\$$pathvar
  case ":$val:" in
    :"$dir":) val= ;;
    :"$dir":*) val=${val#$dir:} ;;
    *:"$dir":) val=${val%:$dir} ;;
    *:"$dir":*) val=${val%%:$dir:*}:${val#*:$dir:} ;;
  esac
  eval $pathvar=\$val
  eval $export
}

## pathhack [-f] +HACK|-HACK...
##
## Each HACK refers to a subdirectory of `~/bin/hacks'.  A hack name preceded
## by `+' adds the directory to the PATH; a `-' removes.  Adding a hack
## that's already on the PATH doesn't do anything unless `-f' is set, in
## which case it gets moved to the beginning.  With no arguments, print the
## currently installed hacks.
pathhack () {
  local p e force arg hack dir
  p=$PATH
  if [ $# -eq 0 ]; then
    while :; do
      e=${p%%:*}
      case "$e" in "$HOME/bin/hacks/"*) echo ${e#$HOME/bin/hacks/} ;; esac
      case "$p" in *:*) p=${p#*:} ;; *) break ;; esac
    done
    return
  fi
  force=nil
  while [ $# -gt 0 ]; do
    arg=$1
    case "$arg" in
      -f | --force) force=t; shift; continue ;;
      --) shift; break ;;
      [-+]*) ;;
      *) break; ;;
    esac
    hack=${arg#[+-]}
    dir=$HOME/bin/hacks/$hack
    if ! [ -d "$dir" ]; then
      echo "$0: path hack $hack not found"
      return 1
    fi
    case "$arg,$force,:$PATH:" in
      -*,*,*:"$dir":*) path_remove p "$dir" ;;
      +*,t,*:"$dir":*) path_remove p "$dir"; path_add p "$dir" ;;
      +*,nil,*:"$dir":*) ;;
      +*,*) path_add p "$dir" ;;
    esac
    shift
  done
  if [ $# -eq 0 ]; then PATH=$p; export PATH
  else PATH=$p "$@"; fi
}

###--------------------------------------------------------------------------
### Finishing touches.

## Make sure `$HOME/bin' is on the path.
path_add "$HOME/bin"

## Set the temporary directory again.  (A setuid or setgid program may have
## unhelpfully forgotten this for us.)
case ${TMPDIR+t} in
  t) ;;
  *) if __mdw_programp tmpdir; then eval $(tmpdir -b); fi ;;
esac

## For `root' use -- some simple molly-guards.
case $(id -u) in
  0)
    alias rm="rm -i" cp="cp -i" mv="mv -i"
    set -o noclobber
    ;;
esac

## Run any local hooks.
__mdw_source_if_exists "$HOME/.shell-local"

###----- That's all, folks --------------------------------------------------