oficsu · May 3, 2025 12:15
diff --git a/fzf-history.sh b/fzf-history.sh
 #!/bin/bash

 # Demonstration: https://youtu.be/Uj3nmYq5LnQ

 # MIT License
 #
 # Copyright (c) 2024 Ofee Oficsu
 #
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal
 # in the Software without restriction, including without limitation the rights
 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 # copies of the Software, and to permit persons to whom the Software is
 # furnished to do so, subject to the following conditions:
 #
 # The above copyright notice and this permission notice shall be included in all
 # copies or substantial portions of the Software.
 #
 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.



 # yes: print warnings and hints on initialization
 # no: print only errors
 MY_FZF_VERBOSE="${MY_FZF_VERBOSE:-yes}"

 # a positive number: count of history search results in lines
 MY_FZF_WIDGET_HEIGHT="${MY_FZF_WIDGET_HEIGHT:-5}"

 # disable or a fzf key, toggle-sort fzf action
 MY_FZF_TOGGLE_SORT_SHORTCUT="${MY_FZF_TOGGLE_SORT_SHORTCUT:-ctrl-s}"

 # disable or a fzf key, toggle-preview fzf action
 MY_FZF_PREVIEW_SHORTCUT="${MY_FZF_PREVIEW_SHORTCUT:-ctrl-p}"

 # disable or a fzf key, execute selected item immediately
 MY_FZF_EVAL_SHORTCUT="${MY_FZF_EVAL_SHORTCUT:-disable}"

 # disable or a fzf key, if an item is selected, execute it; otherwise, paste the query
 MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY="${MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY:-enter}"

 # disable or a fzf key, paste the item with the cursor at the end of the last pattern
 MY_FZF_EDIT_SHORTCUT="${MY_FZF_EDIT_SHORTCUT:-disable}"

 # disable or a fzf key, paste the item with the cursor at the end of the line
 MY_FZF_EDIT_AT_END_SHORTCUT="${MY_FZF_EDIT_AT_END_SHORTCUT:-ctrl-e}"

 # disable or a fzf key, paste the item with the cursor at the start of the line
 MY_FZF_EDIT_AT_START_SHORTCUT="${MY_FZF_EDIT_AT_START_SHORTCUT:-ctrl-a}"

 # disable or a fzf key, paste the query
 MY_FZF_PASTE_QUERY_SHORTCUT="${MY_FZF_PASTE_QUERY_SHORTCUT:-ctrl-w}"

 # disable: arrow keys used for navigation inside the history search query
 # enable: an arrow key immediately substitutes the history element,
 #         closes history search, and moves cursor one character left/right
 MY_FZF_ARROWS_SHORTCUTS="${MY_FZF_ARROWS_SHORTCUTS:-enable}"

 # disable: will display commands only if they match the query
 # enable: will also include commands whose date matches the query
 MY_FZF_SEARCH_BY_DATE="${MY_FZF_SEARCH_BY_DATE:-disable}"

 # dropdown: latest history elements at the top of dropdown
 # dynamic: use dropdown until there is enough space, then invert items order
 # dropdown-reserve: dropdown + reserves space at the bottom of the terminal
 MY_FZF_LAYOUT="${MY_FZF_LAYOUT:-dropdown-reserve}"

 # charcters used for conditional logic in ctrl+r bash binding,
 # they were chosen randomly from the private-use unicode range
 MY_FZF_BINING_HISTORY="${MY_FZF_BINING_HISTORY:-$'\xEE\x8C\xB5'}" # U+E335
 MY_FZF_BINING_ACCEPT="${MY_FZF_BINING_ACCEPT:-$'\xEE\x8C\xB6'}"   # U+E336

 # is an invisible separator between a command and its date;
 # probably you don't want to change it, it will be stripped from the dates
 MY_FZF_CMD_DELIMITER="${MY_FZF_CMD_DELIMITER:-$'\xE2\x81\xA3'}" # U+2063

 # enable: try using bat for bash syntax highlighting in preview window
 # disable: don't try using bat at all
 MY_FZF_HIGHLIGHT_SYNTAX=${MY_FZF_HIGHLIGHT_SYNTAX:-enable}

 # preview highlighting theme, full list available with 'bat --list-themes'
 MY_FZF_HIGHLIGHT_THEME=${MY_FZF_HIGHLIGHT_THEME:-Nord}

 # any extra argument list to pass to underlying fzf invocation
 MY_FZF_EXTRA_ARGS=()



 __my_fzf_history_note__() {
  [ "$MY_FZF_VERBOSE" == no ] && return

  local blue='\033[0;34m'
  local nc='\033[0m'
  echo 1>&2 -e "[${blue}  note   ${nc}][ my fzf history ]" "$@"
 }

 __my_fzf_history_warning__() {
  [ "$MY_FZF_VERBOSE" == no ] && return

  local yellow='\033[0;33m'
  local nc='\033[0m'
  echo 1>&2 -e "[${yellow} warning ${nc}][ my fzf history ]" "$@"
 }

 __my_fzf_history_error__() {
  local red='\033[0;31m'
  local nc='\033[0m'
  echo 1>&2 -e "[${red}  error  ${nc}][ my fzf history ]" "$@"
 }

 __my_fzf_history_reversed__() {
  tac <(HISTFILE=/dev/stdout; history -a) "$HISTFILE"
 }

 __my_fzf_history_highlight_preview__() {
  local width="$FZF_PREVIEW_COLUMNS"

  # a unique invisible character that won't
  # break syntax higlighting in bat like \n
  # see github.com/sharkdp/bat/issues/3079
  local magic=$'\U2062'

  fold --spaces --width "$width"   \
  ` # remove trailing spaces      ` \
  | sed -E 's/\s*$//'                \
  | sed -zE "s/\n/$magic/g"           \
  | bat --tabs 8 ` # as in fold util ` \
        --color=always                  \
        --paging=never                   \
        --decorations=never               \
        --theme "$MY_FZF_HIGHLIGHT_THEME"  \
        "$@"                                \
  | sed -zE "s/$magic/\n/g"
 }

 __my_fzf_history_formatted__() {
  __my_fzf_history_reversed__    \
  | awk -v fmt="$HISTTIMEFORMAT" \
        -v delim="$MY_FZF_CMD_DELIMITER" '
    function print_separated(date, command) {
      # everything will be broken if a date
      # occasionally contains the delimiter,
      # so remove it, it is invisible anyway
      gsub(delim, "", date)
      print date delim command
    }
    {
      if (/#[0-9]+\s*$/) {
        if (prev) {
          ts = substr($0, 2)
          date = strftime(fmt, ts)
          print_separated(date, prev)
        }
        prev = ""
      } else {
        if (prev) { print_separated("", prev) }
        gsub("\\s*$", "", $0)
        if ($0 && !a[$0]++) {
          prev = $0
        } else {
          prev = ""
        }
      }
    }'
 }

 # removes datetime prefix from a fzf output
 __my_fzf_history_extract_command__() {
  grep -Poz "$MY_FZF_CMD_DELIMITER\K[\s\S]*" | tr -d '\0'
 }

 __my_fzf_history_extract_date__() {
  grep -Poz "^[^$MY_FZF_CMD_DELIMITER]*" | tr -d '\0'
 }

 __my_fzf_history_preview__() {
  local date=$(echo "$@" | __my_fzf_history_extract_date__)
  local command=$(echo "$@" | __my_fzf_history_extract_command__)

  if [ "$MY_FZF_HIGHLIGHT_SYNTAX" == enable ]; then
    printf %s\\n "$date" | __my_fzf_history_highlight_preview__ --language log
    printf %s "$command" | __my_fzf_history_highlight_preview__ --language bash
  else
    echo "${date}${command}"
  fi
 }

 # https://stackoverflow.com/questions/2575037
 __my_fzf_history_prompt_pos__() (
  exec < /dev/tty

  local v=()
  local t="$(stty -g)"
  stty -echo
  echo -en "\033[6n" > /dev/tty
  IFS='[;' read -rd R -a v
  stty "$t"
  echo "${v[1]}"
 )

 __my_fzf_history_fzf_version_greater_than__() {
  local test="$1"

  local fzf=$(fzf --version | grep -oP '\d+\.\d+\.\d+')
  local greater=$(echo -e "$test\n$fzf" | sort --version-sort | tail -1)

  [ "$greater" == "$fzf" ]
 }

 __my_fzf_history_selector__() {
  local __my_fzf_history_binds__=(
    --print-query
  )

  if [ "$MY_FZF_TOGGLE_SORT_SHORTCUT" != disable ]; then
    __my_fzf_history_binds__+=(--bind "$MY_FZF_TOGGLE_SORT_SHORTCUT:toggle-sort")
  fi
  if [ "$MY_FZF_PREVIEW_SHORTCUT" != disable ]; then
    __my_fzf_history_binds__+=(--bind "$MY_FZF_PREVIEW_SHORTCUT:toggle-preview")
  fi

  if [ "$MY_FZF_EVAL_SHORTCUT" != disable ]; then
    __my_fzf_history_binds__+=(--expect "$MY_FZF_EVAL_SHORTCUT")
  fi
  if [ "$MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY" != disable ]; then
    __my_fzf_history_binds__+=(--expect "$MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY")
  fi
  if [ "$MY_FZF_EDIT_SHORTCUT" != disable ]; then
    __my_fzf_history_binds__+=(--expect "$MY_FZF_EDIT_SHORTCUT")
  fi
  if [ "$MY_FZF_EDIT_AT_START_SHORTCUT" != disable ]; then
    __my_fzf_history_binds__+=(--expect "$MY_FZF_EDIT_AT_START_SHORTCUT")
  fi
  if [ "$MY_FZF_EDIT_AT_END_SHORTCUT" != disable ]; then
    __my_fzf_history_binds__+=(--expect "$MY_FZF_EDIT_AT_END_SHORTCUT")
  fi
  if [ "$MY_FZF_PASTE_QUERY_SHORTCUT" != disable ]; then
    __my_fzf_history_binds__+=(--expect "$MY_FZF_PASTE_QUERY_SHORTCUT")
  fi
  if [ "$MY_FZF_ARROWS_SHORTCUTS" != disable ]; then
    __my_fzf_history_binds__+=(--expect left,right)
  fi

  local __my_fzf_history_layout__=(
    --layout=reverse
    --bind=ctrl-r:down      # height + prompt
    --height $(( $MY_FZF_WIDGET_HEIGHT + 1 ))
  )

  local pos=$(__my_fzf_history_prompt_pos__)
  local wanted_height=$(($pos + $MY_FZF_WIDGET_HEIGHT))
  if [ "$MY_FZF_LAYOUT" == dynamic ] && (($wanted_height > $LINES)); then
    __my_fzf_history_layout__=(
      --layout=default
      --bind=ctrl-r:up
      --border top   # height + prompt + border
      --height $(( $MY_FZF_WIDGET_HEIGHT + 2 ))
    )
  fi

  # make compatible with fzf < 0.27.2
  local bright_blue=12
  local white=7
  local green=2
  local dark_green=#224433

  local __my_fzf_history_style__=(
    --color=bg+:$dark_green
    --color=hl+:$bright_blue
    --color=hl:$bright_blue
    --color=fg+:$white
    --color=pointer:$green
    --color=gutter:-1
    --pointer=▌

    --ansi
  )

  # debian 11&12 provide too old fzf releases
  if __my_fzf_history_fzf_version_greater_than__ 0.52.0; then
    __my_fzf_history_style__+=(--highlight-line)
  fi

  if __my_fzf_history_fzf_version_greater_than__ 0.42.0; then
    __my_fzf_history_style__+=(--info=inline-right)
  else
    __my_fzf_history_style__+=(--info=hidden)
  fi

  if __my_fzf_history_fzf_version_greater_than__ 0.27.0; then
    __my_fzf_history_style__+=(--preview-window :hidden,right,wrap,border-left)
  else
    __my_fzf_history_style__+=(--preview-window right:wrap:hidden)
  fi

  if __my_fzf_history_fzf_version_greater_than__ 0.28.0; then
    __my_fzf_history_style__+=(--scroll-off 2)
  fi

  if __my_fzf_history_fzf_version_greater_than__ 0.36.0; then
    __my_fzf_history_style__+=(--no-scrollbar)
  fi

  if __my_fzf_history_fzf_version_greater_than__ 0.35.0; then
    __my_fzf_history_style__+=(--no-separator)
  fi

  local __my_fzf_history_args__=(
    --no-multi

    --no-info

    --preview "bash -c 'source $(printf %q "$BASH_SOURCE"); __my_fzf_history_preview__ \"\$@\"' bash {}"

    --prompt="${PS1@P}"

    "${__my_fzf_history_binds__[@]}"
    "${__my_fzf_history_style__[@]}"
    "${__my_fzf_history_layout__[@]}"

    --delimiter "$MY_FZF_CMD_DELIMITER"
  )

  if [ "${MY_FZF_SEARCH_BY_DATE}" == disable ]; then
    __my_fzf_history_args__+=(--nth="2..")
  fi

  if __my_fzf_history_fzf_version_greater_than__ 0.33.0; then
    __my_fzf_history_args__+=(--scheme=history)
  fi

  __my_fzf_history_args__+=("${MY_FZF_EXTRA_ARGS[@]}")

  (
    export FZF_DEFAULT_OPTS=
    export FZF_DEFAULT_OPTS_FILE=
    export FZF_API_KEY=
    export MY_FZF_VERBOSE=no
    __my_fzf_history_formatted__ | fzf "${__my_fzf_history_args__[@]}"
  )
 }

 __my_fzf_history_reserve_space__() (
  local lines=5

  # move cursor down with scrolling
  for _ in `seq $lines`; do
    echo -ne "\eD"
  done

  # move cursor up without scrolling
  echo -ne "\e[${lines}A"
 )

 __my_fzf_history_allow_accept_line__() {
  for m in emacs-standard vi-{command,insert}; do
    bind -m $m '"'$MY_FZF_BINING_ACCEPT'"':accept-line
  done
 }

 __my_fzf_history_block_accept_line__() {
  for m in emacs-standard vi-{command,insert}; do
    bind -m $m -x '"'$MY_FZF_BINING_ACCEPT'"':
  done
 }

 __my_fzf_history_eval_immediately__() {
  if [ -z "$1" ]; then
    return
  fi

  READLINE_LINE="$1"
  __my_fzf_history_allow_accept_line__
 }

 __my_fzf_history_edit_selection__() {
  local cli="$1"
  local pos="$2"
  READLINE_LINE="$cli"
  READLINE_POINT="$pos"

  __my_fzf_history_block_accept_line__
 }

 __my_fzf_history_eval_immediately_or_paste_query__() {
  local item="$1"
  local quey="$2"

  if [ -n "$item" ]; then
    __my_fzf_history_eval_immediately__ "$item"
  else
    __my_fzf_history_edit_selection__ "$query" "${#query}"
  fi
 }

 __my_fzf_history_last_index_of__() {
  local word="$1"
  local string="$2"

  echo "$string" | grep -Fobie "$word" | cut -d: -f1 | tail -1
 }

 __my_fzf_history_last_match_index__() {
  local query="$1"
  local item="$2"
  local expr="$3"

  local result="${#item}"

  for q in ${query[*]}; do
    local index="$(__my_fzf_history_last_index_of__ "$q" "$item")"
    if [ -n "$index" ]; then
      result=$(( "$index" + "${#q}" ))
    fi
  done

  echo $(("$result" "$expr"))
 }

 __my_fzf_history__() {
  # workaround: sometimes bash bindings are
  # broken right after the current function
  # exits or when a command is invoked from
  # the history, so use stty to fix the bug
  # https://unix.stackexchange.com/a/535654
  stty_save="$(stty -g)"
  stty sane
  trap "stty '$stty_save'; trap - RETURN SIGINT" RETURN SIGINT

  local output
  output=$(__my_fzf_history_selector__)
  local status=$?

  local query=$(echo "$output" | sed -n 1p)
  local key=$(echo "$output" | sed -n 2p)
  local item=$(echo "$output" | sed -n 3p | __my_fzf_history_extract_command__)

  case "$status" in
    0)   ;;
    # fzf's "no match"
    1)   ;;
    # fzf's error
    2)   return;;
    # interrupted by ctrl+c or esc
    130) return;;
    # ooops...
    127) __my_fzf_history_error__ invalid shell command for become; return;;
    *)   __my_fzf_history_error__ unexpected exit code: $status; return;;
  esac

  case "$key" in
    # enter by default, if a command is selected, execute it; otherwise, paste the query
    $MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY)
      __my_fzf_history_eval_immediately_or_paste_query__ "$item" "$query";;

    # disabled by default, if a command is selected, execute it; otherwise, do nothing
    $MY_FZF_EVAL_SHORTCUT)
      __my_fzf_history_eval_immediately__ "$item";;

    # disabled by default, edit at the end of the last match
    $MY_FZF_EDIT_SHORTCUT)
      local pos="$(__my_fzf_history_last_match_index__ "$query" "$item")"
      __my_fzf_history_edit_selection__ "$item" "$pos";;

    # ctrl-e by default, edit at the end of the line
    $MY_FZF_EDIT_AT_END_SHORTCUT)
      __my_fzf_history_edit_selection__ "$item" "${#item}";;

    # ctrl-a by default, edit at the start of the line
    $MY_FZF_EDIT_AT_START_SHORTCUT)
      __my_fzf_history_edit_selection__ "$item" 0;;

    # ctrl-w by default, paste the current query
    $MY_FZF_PASTE_QUERY_SHORTCUT)
      __my_fzf_history_edit_selection__ "$query" "${#query}";;

    # right key, edit at the end of the last match
    right)
      local pos="$(__my_fzf_history_last_match_index__ "$query" "$item" +1)"
      __my_fzf_history_edit_selection__ "$item" "$pos";;

    # left key, the same, but moves the cursor one symbol left
    left)
      local pos="$(__my_fzf_history_last_match_index__ "$query" "$item" -1)"
      __my_fzf_history_edit_selection__ "$item" "$pos";;

    *) __my_fzf_history_error__ unexpected key: "'$key'";;
  esac
 }

 if ! command -v 1>/dev/null fzf; then
  __my_fzf_history_warning__ "fzf is not installed, history widget won't be enabled"
  return
 fi

 if [ "$MY_FZF_HIGHLIGHT_SYNTAX" == enable ]; then
  if ! command -v bat &>/dev/null; then
    __my_fzf_history_note__ "bat is not installed, syntax highlight will be disabled"
    MY_FZF_HIGHLIGHT_SYNTAX=disable
  elif ! bat --list-themes | grep -qF "$MY_FZF_HIGHLIGHT_THEME"; then
    __my_fzf_history_warning__ "bat doesn't support selected theme: '$MY_FZF_HIGHLIGHT_THEME'"
    __my_fzf_history_warning__ "  you can set a new theme by setting MY_FZF_HIGHLIGHT_THEME environment variable"
    __my_fzf_history_warning__ "  see 'bat --list-themes' for theme names"
    MY_FZF_HIGHLIGHT_THEME=$(bat --list-themes | head -1)
  fi
 fi

 for m in emacs-standard vi-{command,insert}; do
  {
    bind -m $m -x '"'$MY_FZF_BINING_HISTORY'"':__my_fzf_history__
    bind -m $m    '"'$MY_FZF_BINING_ACCEPT'"':accept-line
    bind -m $m    '"\C-r": "'${MY_FZF_BINING_HISTORY}${MY_FZF_BINING_ACCEPT}'"'
  } 2>/dev/null
 done

 if [ "$MY_FZF_LAYOUT" == dropdown-reserve ]; then
  PROMPT_COMMAND+=$'\n__my_fzf_history_reserve_space__'
 fi
	#!/bin/bash

	# Demonstration: https://youtu.be/Uj3nmYq5LnQ

	# MIT License
	#
	# Copyright (c) 2024 Ofee Oficsu
	#
	# Permission is hereby granted, free of charge, to any person obtaining a copy
	# of this software and associated documentation files (the "Software"), to deal
	# in the Software without restriction, including without limitation the rights
	# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	# copies of the Software, and to permit persons to whom the Software is
	# furnished to do so, subject to the following conditions:
	#
	# The above copyright notice and this permission notice shall be included in all
	# copies or substantial portions of the Software.
	#
	# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	# SOFTWARE.



	# yes: print warnings and hints on initialization
	# no: print only errors
	MY_FZF_VERBOSE="${MY_FZF_VERBOSE:-yes}"

	# a positive number: count of history search results in lines
	MY_FZF_WIDGET_HEIGHT="${MY_FZF_WIDGET_HEIGHT:-5}"

	# disable or a fzf key, toggle-sort fzf action
	MY_FZF_TOGGLE_SORT_SHORTCUT="${MY_FZF_TOGGLE_SORT_SHORTCUT:-ctrl-s}"

	# disable or a fzf key, toggle-preview fzf action
	MY_FZF_PREVIEW_SHORTCUT="${MY_FZF_PREVIEW_SHORTCUT:-ctrl-p}"

	# disable or a fzf key, execute selected item immediately
	MY_FZF_EVAL_SHORTCUT="${MY_FZF_EVAL_SHORTCUT:-disable}"

	# disable or a fzf key, if an item is selected, execute it; otherwise, paste the query
	MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY="${MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY:-enter}"

	# disable or a fzf key, paste the item with the cursor at the end of the last pattern
	MY_FZF_EDIT_SHORTCUT="${MY_FZF_EDIT_SHORTCUT:-disable}"

	# disable or a fzf key, paste the item with the cursor at the end of the line
	MY_FZF_EDIT_AT_END_SHORTCUT="${MY_FZF_EDIT_AT_END_SHORTCUT:-ctrl-e}"

	# disable or a fzf key, paste the item with the cursor at the start of the line
	MY_FZF_EDIT_AT_START_SHORTCUT="${MY_FZF_EDIT_AT_START_SHORTCUT:-ctrl-a}"

	# disable or a fzf key, paste the query
	MY_FZF_PASTE_QUERY_SHORTCUT="${MY_FZF_PASTE_QUERY_SHORTCUT:-ctrl-w}"

	# disable: arrow keys used for navigation inside the history search query
	# enable: an arrow key immediately substitutes the history element,
	# closes history search, and moves cursor one character left/right
	MY_FZF_ARROWS_SHORTCUTS="${MY_FZF_ARROWS_SHORTCUTS:-enable}"

	# disable: will display commands only if they match the query
	# enable: will also include commands whose date matches the query
	MY_FZF_SEARCH_BY_DATE="${MY_FZF_SEARCH_BY_DATE:-disable}"

	# dropdown: latest history elements at the top of dropdown
	# dynamic: use dropdown until there is enough space, then invert items order
	# dropdown-reserve: dropdown + reserves space at the bottom of the terminal
	MY_FZF_LAYOUT="${MY_FZF_LAYOUT:-dropdown-reserve}"

	# charcters used for conditional logic in ctrl+r bash binding,
	# they were chosen randomly from the private-use unicode range
	MY_FZF_BINING_HISTORY="${MY_FZF_BINING_HISTORY:-$'\xEE\x8C\xB5'}" # U+E335
	MY_FZF_BINING_ACCEPT="${MY_FZF_BINING_ACCEPT:-$'\xEE\x8C\xB6'}" # U+E336

	# is an invisible separator between a command and its date;
	# probably you don't want to change it, it will be stripped from the dates
	MY_FZF_CMD_DELIMITER="${MY_FZF_CMD_DELIMITER:-$'\xE2\x81\xA3'}" # U+2063

	# enable: try using bat for bash syntax highlighting in preview window
	# disable: don't try using bat at all
	MY_FZF_HIGHLIGHT_SYNTAX=${MY_FZF_HIGHLIGHT_SYNTAX:-enable}

	# preview highlighting theme, full list available with 'bat --list-themes'
	MY_FZF_HIGHLIGHT_THEME=${MY_FZF_HIGHLIGHT_THEME:-Nord}

	# any extra argument list to pass to underlying fzf invocation
	MY_FZF_EXTRA_ARGS=()



	__my_fzf_history_note__() {
	[ "$MY_FZF_VERBOSE" == no ] && return

	local blue='\033[0;34m'
	local nc='\033[0m'
	echo 1>&2 -e "[${blue} note ${nc}][ my fzf history ]" "$@"
	}

	__my_fzf_history_warning__() {
	[ "$MY_FZF_VERBOSE" == no ] && return

	local yellow='\033[0;33m'
	local nc='\033[0m'
	echo 1>&2 -e "[${yellow} warning ${nc}][ my fzf history ]" "$@"
	}

	__my_fzf_history_error__() {
	local red='\033[0;31m'
	local nc='\033[0m'
	echo 1>&2 -e "[${red} error ${nc}][ my fzf history ]" "$@"
	}

	__my_fzf_history_reversed__() {
	tac <(HISTFILE=/dev/stdout; history -a) "$HISTFILE"
	}

	__my_fzf_history_highlight_preview__() {
	local width="$FZF_PREVIEW_COLUMNS"

	# a unique invisible character that won't
	# break syntax higlighting in bat like \n
	# see github.com/sharkdp/bat/issues/3079
	local magic=$'\U2062'

	fold --spaces --width "$width" \
	` # remove trailing spaces ` \
	\| sed -E 's/\s*$//' \
	\| sed -zE "s/\n/$magic/g" \
	\| bat --tabs 8 ` # as in fold util ` \
	--color=always \
	--paging=never \
	--decorations=never \
	--theme "$MY_FZF_HIGHLIGHT_THEME" \
	"$@" \
	\| sed -zE "s/$magic/\n/g"
	}

	__my_fzf_history_formatted__() {
	__my_fzf_history_reversed__ \
	\| awk -v fmt="$HISTTIMEFORMAT" \
	-v delim="$MY_FZF_CMD_DELIMITER" '
	function print_separated(date, command) {
	# everything will be broken if a date
	# occasionally contains the delimiter,
	# so remove it, it is invisible anyway
	gsub(delim, "", date)
	print date delim command
	}
	{
	if (/#[0-9]+\s*$/) {
	if (prev) {
	ts = substr($0, 2)
	date = strftime(fmt, ts)
	print_separated(date, prev)
	}
	prev = ""
	} else {
	if (prev) { print_separated("", prev) }
	gsub("\\s*$", "", $0)
	if ($0 && !a[$0]++) {
	prev = $0
	} else {
	prev = ""
	}
	}
	}'
	}

	# removes datetime prefix from a fzf output
	__my_fzf_history_extract_command__() {
	grep -Poz "$MY_FZF_CMD_DELIMITER\K[\s\S]*" \| tr -d '\0'
	}

	__my_fzf_history_extract_date__() {
	grep -Poz "^[^$MY_FZF_CMD_DELIMITER]*" \| tr -d '\0'
	}

	__my_fzf_history_preview__() {
	local date=$(echo "$@" \| __my_fzf_history_extract_date__)
	local command=$(echo "$@" \| __my_fzf_history_extract_command__)

	if [ "$MY_FZF_HIGHLIGHT_SYNTAX" == enable ]; then
	printf %s\\n "$date" \| __my_fzf_history_highlight_preview__ --language log
	printf %s "$command" \| __my_fzf_history_highlight_preview__ --language bash
	else
	echo "${date}${command}"
	fi
	}

	# https://stackoverflow.com/questions/2575037
	__my_fzf_history_prompt_pos__() (
	exec < /dev/tty

	local v=()
	local t="$(stty -g)"
	stty -echo
	echo -en "\033[6n" > /dev/tty
	IFS='[;' read -rd R -a v
	stty "$t"
	echo "${v[1]}"
	)

	__my_fzf_history_fzf_version_greater_than__() {
	local test="$1"

	local fzf=$(fzf --version \| grep -oP '\d+\.\d+\.\d+')
	local greater=$(echo -e "$test\n$fzf" \| sort --version-sort \| tail -1)

	[ "$greater" == "$fzf" ]
	}

	__my_fzf_history_selector__() {
	local __my_fzf_history_binds__=(
	--print-query
	)

	if [ "$MY_FZF_TOGGLE_SORT_SHORTCUT" != disable ]; then
	__my_fzf_history_binds__+=(--bind "$MY_FZF_TOGGLE_SORT_SHORTCUT:toggle-sort")
	fi
	if [ "$MY_FZF_PREVIEW_SHORTCUT" != disable ]; then
	__my_fzf_history_binds__+=(--bind "$MY_FZF_PREVIEW_SHORTCUT:toggle-preview")
	fi

	if [ "$MY_FZF_EVAL_SHORTCUT" != disable ]; then
	__my_fzf_history_binds__+=(--expect "$MY_FZF_EVAL_SHORTCUT")
	fi
	if [ "$MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY" != disable ]; then
	__my_fzf_history_binds__+=(--expect "$MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY")
	fi
	if [ "$MY_FZF_EDIT_SHORTCUT" != disable ]; then
	__my_fzf_history_binds__+=(--expect "$MY_FZF_EDIT_SHORTCUT")
	fi
	if [ "$MY_FZF_EDIT_AT_START_SHORTCUT" != disable ]; then
	__my_fzf_history_binds__+=(--expect "$MY_FZF_EDIT_AT_START_SHORTCUT")
	fi
	if [ "$MY_FZF_EDIT_AT_END_SHORTCUT" != disable ]; then
	__my_fzf_history_binds__+=(--expect "$MY_FZF_EDIT_AT_END_SHORTCUT")
	fi
	if [ "$MY_FZF_PASTE_QUERY_SHORTCUT" != disable ]; then
	__my_fzf_history_binds__+=(--expect "$MY_FZF_PASTE_QUERY_SHORTCUT")
	fi
	if [ "$MY_FZF_ARROWS_SHORTCUTS" != disable ]; then
	__my_fzf_history_binds__+=(--expect left,right)
	fi

	local __my_fzf_history_layout__=(
	--layout=reverse
	--bind=ctrl-r:down # height + prompt
	--height $(( $MY_FZF_WIDGET_HEIGHT + 1 ))
	)

	local pos=$(__my_fzf_history_prompt_pos__)
	local wanted_height=$(($pos + $MY_FZF_WIDGET_HEIGHT))
	if [ "$MY_FZF_LAYOUT" == dynamic ] && (($wanted_height > $LINES)); then
	__my_fzf_history_layout__=(
	--layout=default
	--bind=ctrl-r:up
	--border top # height + prompt + border
	--height $(( $MY_FZF_WIDGET_HEIGHT + 2 ))
	)
	fi

	# make compatible with fzf < 0.27.2
	local bright_blue=12
	local white=7
	local green=2
	local dark_green=#224433

	local __my_fzf_history_style__=(
	--color=bg+:$dark_green
	--color=hl+:$bright_blue
	--color=hl:$bright_blue
	--color=fg+:$white
	--color=pointer:$green
	--color=gutter:-1
	--pointer=▌

	--ansi
	)

	# debian 11&12 provide too old fzf releases
	if __my_fzf_history_fzf_version_greater_than__ 0.52.0; then
	__my_fzf_history_style__+=(--highlight-line)
	fi

	if __my_fzf_history_fzf_version_greater_than__ 0.42.0; then
	__my_fzf_history_style__+=(--info=inline-right)
	else
	__my_fzf_history_style__+=(--info=hidden)
	fi

	if __my_fzf_history_fzf_version_greater_than__ 0.27.0; then
	__my_fzf_history_style__+=(--preview-window :hidden,right,wrap,border-left)
	else
	__my_fzf_history_style__+=(--preview-window right:wrap:hidden)
	fi

	if __my_fzf_history_fzf_version_greater_than__ 0.28.0; then
	__my_fzf_history_style__+=(--scroll-off 2)
	fi

	if __my_fzf_history_fzf_version_greater_than__ 0.36.0; then
	__my_fzf_history_style__+=(--no-scrollbar)
	fi

	if __my_fzf_history_fzf_version_greater_than__ 0.35.0; then
	__my_fzf_history_style__+=(--no-separator)
	fi

	local __my_fzf_history_args__=(
	--no-multi

	--no-info

	--preview "bash -c 'source $(printf %q "$BASH_SOURCE"); __my_fzf_history_preview__ \"\$@\"' bash {}"

	--prompt="${PS1@P}"

	"${__my_fzf_history_binds__[@]}"
	"${__my_fzf_history_style__[@]}"
	"${__my_fzf_history_layout__[@]}"

	--delimiter "$MY_FZF_CMD_DELIMITER"
	)

	if [ "${MY_FZF_SEARCH_BY_DATE}" == disable ]; then
	__my_fzf_history_args__+=(--nth="2..")
	fi

	if __my_fzf_history_fzf_version_greater_than__ 0.33.0; then
	__my_fzf_history_args__+=(--scheme=history)
	fi

	__my_fzf_history_args__+=("${MY_FZF_EXTRA_ARGS[@]}")

	(
	export FZF_DEFAULT_OPTS=
	export FZF_DEFAULT_OPTS_FILE=
	export FZF_API_KEY=
	export MY_FZF_VERBOSE=no
	__my_fzf_history_formatted__ \| fzf "${__my_fzf_history_args__[@]}"
	)
	}

	__my_fzf_history_reserve_space__() (
	local lines=5

	# move cursor down with scrolling
	for _ in `seq $lines`; do
	echo -ne "\eD"
	done

	# move cursor up without scrolling
	echo -ne "\e[${lines}A"
	)

	__my_fzf_history_allow_accept_line__() {
	for m in emacs-standard vi-{command,insert}; do
	bind -m $m '"'$MY_FZF_BINING_ACCEPT'"':accept-line
	done
	}

	__my_fzf_history_block_accept_line__() {
	for m in emacs-standard vi-{command,insert}; do
	bind -m $m -x '"'$MY_FZF_BINING_ACCEPT'"':
	done
	}

	__my_fzf_history_eval_immediately__() {
	if [ -z "$1" ]; then
	return
	fi

	READLINE_LINE="$1"
	__my_fzf_history_allow_accept_line__
	}

	__my_fzf_history_edit_selection__() {
	local cli="$1"
	local pos="$2"
	READLINE_LINE="$cli"
	READLINE_POINT="$pos"

	__my_fzf_history_block_accept_line__
	}

	__my_fzf_history_eval_immediately_or_paste_query__() {
	local item="$1"
	local quey="$2"

	if [ -n "$item" ]; then
	__my_fzf_history_eval_immediately__ "$item"
	else
	__my_fzf_history_edit_selection__ "$query" "${#query}"
	fi
	}

	__my_fzf_history_last_index_of__() {
	local word="$1"
	local string="$2"

	echo "$string" \| grep -Fobie "$word" \| cut -d: -f1 \| tail -1
	}

	__my_fzf_history_last_match_index__() {
	local query="$1"
	local item="$2"
	local expr="$3"

	local result="${#item}"

	for q in ${query[*]}; do
	local index="$(__my_fzf_history_last_index_of__ "$q" "$item")"
	if [ -n "$index" ]; then
	result=$(( "$index" + "${#q}" ))
	fi
	done

	echo $(("$result" "$expr"))
	}

	__my_fzf_history__() {
	# workaround: sometimes bash bindings are
	# broken right after the current function
	# exits or when a command is invoked from
	# the history, so use stty to fix the bug
	# https://unix.stackexchange.com/a/535654
	stty_save="$(stty -g)"
	stty sane
	trap "stty '$stty_save'; trap - RETURN SIGINT" RETURN SIGINT

	local output
	output=$(__my_fzf_history_selector__)
	local status=$?

	local query=$(echo "$output" \| sed -n 1p)
	local key=$(echo "$output" \| sed -n 2p)
	local item=$(echo "$output" \| sed -n 3p \| __my_fzf_history_extract_command__)

	case "$status" in
	0) ;;
	# fzf's "no match"
	1) ;;
	# fzf's error
	2) return;;
	# interrupted by ctrl+c or esc
	130) return;;
	# ooops...
	127) __my_fzf_history_error__ invalid shell command for become; return;;
	*) __my_fzf_history_error__ unexpected exit code: $status; return;;
	esac

	case "$key" in
	# enter by default, if a command is selected, execute it; otherwise, paste the query
	$MY_FZF_EVAL_SHORTCUT_OR_PASTE_QUERY)
	__my_fzf_history_eval_immediately_or_paste_query__ "$item" "$query";;

	# disabled by default, if a command is selected, execute it; otherwise, do nothing
	$MY_FZF_EVAL_SHORTCUT)
	__my_fzf_history_eval_immediately__ "$item";;

	# disabled by default, edit at the end of the last match
	$MY_FZF_EDIT_SHORTCUT)
	local pos="$(__my_fzf_history_last_match_index__ "$query" "$item")"
	__my_fzf_history_edit_selection__ "$item" "$pos";;

	# ctrl-e by default, edit at the end of the line
	$MY_FZF_EDIT_AT_END_SHORTCUT)
	__my_fzf_history_edit_selection__ "$item" "${#item}";;

	# ctrl-a by default, edit at the start of the line
	$MY_FZF_EDIT_AT_START_SHORTCUT)
	__my_fzf_history_edit_selection__ "$item" 0;;

	# ctrl-w by default, paste the current query
	$MY_FZF_PASTE_QUERY_SHORTCUT)
	__my_fzf_history_edit_selection__ "$query" "${#query}";;

	# right key, edit at the end of the last match
	right)
	local pos="$(__my_fzf_history_last_match_index__ "$query" "$item" +1)"
	__my_fzf_history_edit_selection__ "$item" "$pos";;

	# left key, the same, but moves the cursor one symbol left
	left)
	local pos="$(__my_fzf_history_last_match_index__ "$query" "$item" -1)"
	__my_fzf_history_edit_selection__ "$item" "$pos";;

	*) __my_fzf_history_error__ unexpected key: "'$key'";;
	esac
	}

	if ! command -v 1>/dev/null fzf; then
	__my_fzf_history_warning__ "fzf is not installed, history widget won't be enabled"
	return
	fi

	if [ "$MY_FZF_HIGHLIGHT_SYNTAX" == enable ]; then
	if ! command -v bat &>/dev/null; then
	__my_fzf_history_note__ "bat is not installed, syntax highlight will be disabled"
	MY_FZF_HIGHLIGHT_SYNTAX=disable
	elif ! bat --list-themes \| grep -qF "$MY_FZF_HIGHLIGHT_THEME"; then
	__my_fzf_history_warning__ "bat doesn't support selected theme: '$MY_FZF_HIGHLIGHT_THEME'"
	__my_fzf_history_warning__ " you can set a new theme by setting MY_FZF_HIGHLIGHT_THEME environment variable"
	__my_fzf_history_warning__ " see 'bat --list-themes' for theme names"
	MY_FZF_HIGHLIGHT_THEME=$(bat --list-themes \| head -1)
	fi
	fi

	for m in emacs-standard vi-{command,insert}; do
	{
	bind -m $m -x '"'$MY_FZF_BINING_HISTORY'"':__my_fzf_history__
	bind -m $m '"'$MY_FZF_BINING_ACCEPT'"':accept-line
	bind -m $m '"\C-r": "'${MY_FZF_BINING_HISTORY}${MY_FZF_BINING_ACCEPT}'"'
	} 2>/dev/null
	done

	if [ "$MY_FZF_LAYOUT" == dropdown-reserve ]; then
	PROMPT_COMMAND+=$'\n__my_fzf_history_reserve_space__'
	fi