functions

# Simple calculator
function calc() {
	local result="";
	result="$(printf "scale=10;$*\n" | bc --mathlib | tr -d '\\\n')";
	#                       └─ default (when `--mathlib` is used) is 20
	#
	if [[ "$result" == *.* ]]; then
		# improve the output for decimal numbers
		printf "$result" |
		sed -e 's/^\./0./'        `# add "0" for cases like ".5"` \
		    -e 's/^-\./-0./'      `# add "0" for cases like "-.5"`\
		    -e 's/0*$//;s/\.$//';  # remove trailing zeros
	else
		printf "$result";
	fi;
	printf "\n";
}

# Determine size of a file or total size of a directory
function fs() {
	if du -b /dev/null > /dev/null 2>&1; then
		local arg=-sbh;
	else
		local arg=-sh;
	fi
	if [[ -n "$@" ]]; then
		du $arg -- "$@";
	else
		du $arg .[^.]* ./*;
	fi;
}

# `tre` is a shorthand for `tree` with hidden files and color enabled, ignoring
# the `.git` directory, listing directories first. The output gets piped into
# `less` with options to preserve color and line numbers, unless the output is
# small enough for one screen.
function tre() {
	tree -aC -I '.git|node_modules|bower_components' --dirsfirst "$@" | less -FRNX;
}

# Simple wrappers around `find`
function fn() { find . -name "*$@*"; }
function fe() { find . -name "*.$@"; }

# Better calendar:
#   * shows whole year
#   * current day is highlighted
#   * weekends are highlighted
function cal() {
    local year=$(date +%Y)
    local red="$(tput setaf 1)";
    local res="$(tput sgr0)";
    # `sed` expression is for Mac OS X' sed (maybe use gsed instead?)
    gcal --starting-day=1 -H yes -q RU ${1:-$year} | sed -E "/^S[ua]/s/"$'\E'"\[0m/$res$red/g" | sed "s/^S[au].*$/$red&$res/";
}

# remove duplicates while preserving input order
function dedup {
   awk '! x[$0]++' $@
}

# removes $HISTIGNORE commands from input
function remove_histignore {
   if [ -n "$HISTIGNORE" ]; then
      # replace : with |, then * with .*
      local IGNORE_PAT=`echo "$HISTIGNORE" | sed s/\:/\|/g | sed s/\*/\.\*/g`
      # negated grep removes matches
      grep -vx "$IGNORE_PAT" $@
   else
      cat $@
   fi
}

# clean up the history file by remove duplicates and commands matching
# $HISTIGNORE entries
function history_cleanup {
   local HISTFILE_SRC=~/.bash_history
   local HISTFILE_DST=/tmp/.$USER.bash_history.clean
   if [ -f $HISTFILE_SRC ]; then
      \cp $HISTFILE_SRC $HISTFILE_SRC.backup
      dedup $HISTFILE_SRC | remove_histignore >| $HISTFILE_DST
      \mv $HISTFILE_DST $HISTFILE_SRC
      chmod go-r $HISTFILE_SRC
      history -c
      history -r
   fi
}

# GIT heart FZF (https://gist.github.com/junegunn/8b572b8d4b5eddd8b85e5f4d40f17236)
# -------------

is_in_git_repo() {
  git rev-parse HEAD > /dev/null 2>&1
}

fzf-down() {
  fzf --height 50% "$@" --border
}

git-fzf-gf() {
  is_in_git_repo || return
  git -c color.status=always status --short |
  fzf-down -m --ansi --nth 2..,.. \
    --preview '(git diff --color=always -- {-1} | sed 1,4d; cat {-1}) | head -500' |
  cut -c4- | sed 's/.* -> //'
}

git-fzf-gb() {
  is_in_git_repo || return
  git branch -a --color=always | grep -v '/HEAD\s' | sort |
  fzf-down --ansi --multi --tac --preview-window right:70% \
    --preview 'git log --oneline --graph --date=short --pretty="format:%C(auto)%cd %h%d %s" $(sed s/^..// <<< {} | cut -d" " -f1) | head -'$LINES |
  sed 's/^..//' | cut -d' ' -f1 |
  sed 's#^remotes/##'
}

git-fzf-gt() {
  is_in_git_repo || return
  git tag --sort -version:refname |
  fzf-down --multi --preview-window right:70% \
    --preview 'git show --color=always {} | head -'$LINES
}

git-fzf-gh() {
  is_in_git_repo || return
  git log --date=short --format="%C(green)%C(bold)%cd %C(auto)%h%d %s (%an)" --graph --color=always |
  fzf-down --ansi --no-sort --reverse --multi --bind 'ctrl-s:toggle-sort' \
    --header 'Press CTRL-S to toggle sort' \
    --preview 'grep -o "[a-f0-9]\{7,\}" <<< {} | xargs git show --color=always | head -'$LINES |
  grep -o "[a-f0-9]\{7,\}"
}

git-fzf-gr() {
  is_in_git_repo || return
  git remote -v | awk '{print $1 "\t" $2}' | uniq |
  fzf-down --tac \
    --preview 'git log --oneline --graph --date=short --pretty="format:%C(auto)%cd %h%d %s" {1} | head -200' |
  cut -d$'\t' -f1
}