# cdeh v2.1 -- an automatic history and environment switch system.
#
# Copyright (C) 2007 (v1.0), 2020 (v2.0)  Carlo Wood <carlo@alinoe.com>
#
# $1 : PID of the shell
# $2 : $HISTFILE
#
EXITCODE=1
KEEP_ENVFILES=
CDEH_TMP="/tmp/cdeh.$CDEH_USER/$1"
if test -n "$CDEH_VERBOSE"; then
  echo "$1 EXECUTING PROMPT_COMMAND"
fi
if ! test -d "$CDEH_TMP"; then
  if test -n "$CDEH_VERBOSE"; then
    echo -n "$1 "
  fi
  echo "Recreating $CDEH_TMP" 2>&1
  mkdir -p "$CDEH_TMP"
fi
if ! expr "$2" : "^$CDEH_HISTROOT/" >/dev/null; then
  # In case this is the very first time we run this, do some initialization.
  if ! test -f "$CDEH_HISTROOT/history"; then
    if ! test -d "$CDEH_HISTROOT"; then
      echo "$0: WARNING: \"$CDEH_HISTROOT\": No such directory."
    fi
    touch "$CDEH_HISTROOT/history"
  fi
  echo "Reloading history for $HOME"
  HISTSIZE=$CDEH_HISTSIZE
  history -r "$CDEH_HISTROOT/history"
  PREVIOUS_DIR="nothing"
else
  if test -e "$CDEH_TMP/prevwd"; then
    source "$CDEH_TMP/prevwd"
  fi
  if test -n "$CDEH_REMOVE_STORE"; then
    echo 'unset CDEH_REMOVE_STORE' > "$CDEH_TMP/store.env"
    echo "$CDEH_TMP/store.env" > "$CDEH_TMP/envfiles"
    KEEP_ENVFILES=1
    rm -f "$CDEH_TMP/histfile"
    EXITCODE=0
  fi
fi
if test "$CDEH_STORE_ENVIRONMENT" = "yes"; then
  if test -n "$CDEH_VERBOSE"; then
    echo 'echo "$1 SAVING ENTIRE ENVIRONMENT to $CDEH_TMP/env.base"' > "$CDEH_TMP/store.env";
  else
    echo -n > "$CDEH_TMP/store.env";
  fi
  declare -f __cdeh_store_environment | grep -v '^[_{}]' >> "$CDEH_TMP/store.env"
  echo 'export CDEH_REMOVE_STORE=1' >> "$CDEH_TMP/store.env"
  echo 'CDEH_STORE_ENVIRONMENT=' >> "$CDEH_TMP/store.env"
  echo "$CDEH_TMP/store.env" > "$CDEH_TMP/envfiles"
  KEEP_ENVFILES=1
  EXITCODE=0
fi
if [ "$PREVIOUS_DIR" != "$PWD" ]; then
  echo "PREVIOUS_DIR=\"$PWD\"" > "$CDEH_TMP/prevwd"
  rm -f "$CDEH_TMP/histfile"
  if test -z "$KEEP_ENVFILES"; then
    rm -f "$CDEH_TMP/envfiles"
  fi
  CURRENT_DIR="$PWD"
  CDEH_NEW_DIR=
  until [ "$CURRENT_DIR" = "" ]; do
    if [ -f "$CDEH_HISTROOT/$CURRENT_DIR/history" ]; then
      CDEH_NEW_DIR="$CURRENT_DIR"
      break
    fi
    CURRENT_DIR="${CURRENT_DIR%/*}"
  done
  if [ "$CURRENT_DIR" = "" ]; then
    CURRENT_DIR="/"
  fi
  if [ "$CURRENT_DIR" = "/" -a -f "$CDEH_HISTROOT/history" ]; then
    CDEH_NEW_DIR="/"
  fi
  if [ "$CDEH_NEW_DIR" = "" ]; then
    CDEH_NEW_DIR="/"
  fi
  INODE=$(stat "$CDEH_NEW_DIR" | awk '/^Device:/ { printf("%s:%d\n",$2, $4); }')
  if [ -f "$CDEH_TMP/prevhd" ]; then
    source "$CDEH_TMP/prevhd"
  else
    PREVIOUS_INODE=
  fi
  if [ "$PREVIOUS_INODE" != "$INODE" ]; then
    echo "PREVIOUS_INODE=$INODE" > "$CDEH_TMP/prevhd"
    echo "PREVIOUS_DIR=\"$CDEH_NEW_DIR\"" >> "$CDEH_TMP/prevhd"
    if [ "$2" != "$CDEH_HISTROOT/$CURRENT_DIR/history" ]; then
      history -w "$CDEH_HISTROOT/$PREVIOUS_DIR/history"
      echo "$CDEH_HISTROOT/$CURRENT_DIR/history" > "$CDEH_TMP/histfile"
      echo "History changed from \"$PREVIOUS_DIR\" to \"$CURRENT_DIR\""
      EXITCODE=0
    fi
  fi
  __cdeh_rebuild_source_dirs
  TITLE="`echo "[$CDEH_CURRENT_DIR]$PWD" | sed -e 's%\[[^]]*/%[%' -e 's%\(\[[^]]*\]\)'"$CDEH_CURRENT_DIR"'%\1 %' -e 's%\[\]%[/]%' -e 's% $%%' -e 's%^\[/\]$%'"$PWD"'%'`"
  #xtermset -title "$TITLE"
  echo -ne "\033]30;$TITLE\007"
  test -z "$CDEH_VERBOSE" || echo "$1 CDEH_NEW_DIR is now \"$CDEH_NEW_DIR\""
  INODE=$(stat "$CDEH_NEW_DIR" | awk '/^Device:/ { printf("%s:%d\n",$2, $4); }')
  if [ -f "$CDEH_TMP/preved" ]; then
    source "$CDEH_TMP/preved"
  else
    PREVIOUS_INODE=
    PREVIOUS_DIR="nothing"
  fi
  test -z "$CDEH_VERBOSE" || echo "$1 PREVIOUS_INODE='$PREVIOUS_INODE'; PREVIOUS_DIR=\"$PREVIOUS_DIR\"; INODE='$INODE'"
  if [ "$PREVIOUS_INODE" != "$INODE" ]; then
    echo "PREVIOUS_INODE=$INODE" > "$CDEH_TMP/preved"
    echo "PREVIOUS_DIR=\"$CDEH_NEW_DIR\"" >> "$CDEH_TMP/preved"
    __cdeh_rebuild_envfiles
    NEW_CDEH_ENVFILES=$(cat "$CDEH_TMP/envfiles")
    test -z "$CDEH_VERBOSE" || echo "$1 CDEH_ENVFILES=\""$CDEH_ENVFILES"\"; NEW_CDEH_ENVFILES=\""$NEW_CDEH_ENVFILES"\""
    if [ "$CDEH_ENVFILES" != "$NEW_CDEH_ENVFILES" ]; then
      test -z "$CDEH_VERBOSE" || echo "$1 resource, because CDEH_ENVFILES ("$CDEH_ENVFILES") != NEW_CDEH_ENVFILES ("$NEW_CDEH_ENVFILES")"
      if test "$PREVIOUS_DIR" != "$CDEH_CURRENT_DIR"; then
        echo "Environment changed from \"$PREVIOUS_DIR\" to \"$CDEH_CURRENT_DIR\""
      fi
      EXITCODE=0
    fi
  fi
fi
exit $EXITCODE