zsh/prompt_fresh_setup

prompt_fresh_help() {
  echo "\
options:
        -a      enable almostontop like behaviour
        -r      recompile git-prompt executable"
}

prompt_fresh_setup() {
  # Parse options
  local almostontop=0
  local recompile=0
  while getopts 'ar' opt; do
    case $opt in
      a) local almostontop=1 ;;
      r) local recompile=1 ;;
      *) prompt -h fresh; return 1 ;;
    esac
  done

  autoload -U add-zsh-hook

  # Hook to print the first line of the "two line" prompt, this line is not
  # actually part of the prompt so does not get redrawn, this is preferable
  # since sometimes lines before the prompt can disappear.
  add-zsh-hook precmd fresh_line_one

  if [ $almostontop -eq 1 ]; then
    # Hook to clear the screen then prints the prompt with previous command at
    # the top of the screen.
    add-zsh-hook preexec fresh_almostontop
  else
    add-zsh-hook -d preexec fresh_almostontop
  fi

  [ $recompile -eq 1 ] && prompt_cleanup
  fresh_compile_git_prompt

  if [ "$USER" = "root" ]; then
    local user="%{%F{1}%}%n%{%f%}"
  else
    local user="%{%F{35}%}%n%{%f%}"
  fi

  local userhost=$USER
  if [ "$SSH_CONNECTION" != "" ]; then
    local user="$user@%{%F{244}%}%M%{%f%}"
    local userhost="$userhost@`hostname`"
  fi

  PS1="«$user» "
  PS2="«${(l:${#userhost}:: :)}» "

  prompt_opts=(percent sp subst)
}

prompt_cleanup() {
  [ -f ~/.cache/zsh/git-prompt ] && rm ~/.cache/zsh/git-prompt
}

fresh_line_one() {
  # First get the last commands exit code before doing anything
  local exit_code=$?

  # Construct the time and directory portions of the prompt
  local time_stamp="%{%F{244}%}%D{%H:%M:%S}%{%f%}"
  [[ -n $SANDBOX_HOME ]] && \
    local directory="%{%F{3}%}$SANDBOX_NAME${PWD#$SANDBOX_HOME}%{%f%}" || \
    local directory="%{%F{37}%}%~%{%f%}"

  # Check we are in a git repository
  local git=`~/.cache/zsh/git-prompt`

  # If the last command failed, display its error code at the right
  if [[ $exit_code -ne 0 ]]; then
    case $exit_code in
      129) exit_code="SIGHUP"     ;;  # 128 + 1
      130) exit_code="SIGINT"     ;;  # 128 + 2
      131) exit_code="SIGQUIT"    ;;  # 128 + 3
      132) exit_code="SIGILL"     ;;  # 128 + 4
      133) exit_code="SIGTRAP"    ;;  # 128 + 5
      134) exit_code="SIGABRT"    ;;  # 128 + 6
      134) exit_code="SIGIOT"     ;;  # 128 + 6
      135) exit_code="SIGBUS"     ;;  # 128 + 7
      136) exit_code="SIGFPE"     ;;  # 128 + 8
      137) exit_code="SIGKILL"    ;;  # 128 + 9
      138) exit_code="SIGUSR1"    ;;  # 128 + 10
      139) exit_code="SIGSEGV"    ;;  # 128 + 11
      140) exit_code="SIGUSR2"    ;;  # 128 + 12
      141) exit_code="SIGPIPE"    ;;  # 128 + 13
      142) exit_code="SIGALRM"    ;;  # 128 + 14
      143) exit_code="SIGTERM"    ;;  # 128 + 15
      144) exit_code="SIGSTKFLT"  ;;  # 128 + 16
      145) exit_code="SIGCHLD"    ;;  # 128 + 17
      146) exit_code="SIGCONT"    ;;  # 128 + 18
      147) exit_code="SIGSTOP"    ;;  # 128 + 19
      148) exit_code="SIGTSTP"    ;;  # 128 + 20
      149) exit_code="SIGTTIN"    ;;  # 128 + 21
      150) exit_code="SIGTTOU"    ;;  # 128 + 22
      151) exit_code="SIGURG"     ;;  # 128 + 23
      152) exit_code="SIGXCPU"    ;;  # 128 + 24
      153) exit_code="SIGXFSZ"    ;;  # 128 + 25
      154) exit_code="SIGVTALRM"  ;;  # 128 + 26
      155) exit_code="SIGPROF"    ;;  # 128 + 27
      156) exit_code="SIGWINCH"   ;;  # 128 + 28
      157) exit_code="SIGIO"      ;;  # 128 + 29
      158) exit_code="SIGPWR"     ;;  # 128 + 30
      159) exit_code="SIGSYS"     ;;  # 128 + 31
    esac
    local result=" %{%B%F{1}%}$exit_code%{%f%b%}"
  fi

  # Unset vim/tmux navigate flag to handle C-z and multiple vim jobs.
  [[ ! -z "$TMUX" ]] && \
    [[ "`tmux show-window-options`" = *"@vim$TMUX_PANE"* ]] && \
      tmux set-window-option -u @vim$TMUX_PANE

  # If a virtualenv is enabled, display it's basename
  if [[ ! -z "$VIRTUAL_ENV" ]]; then
    local py=" %{%F{4}%}py%{%f%}%{%F{3}%}$(basename $VIRTUAL_ENV)%{%f%}"
  fi

  # If docker-machine env is active, display the machines name
  if [[ ! -z "$DOCKER_MACHINE_NAME" ]]; then
    local docker=" %{%F{6}%}$DOCKER_MACHINE_NAME%{%f%}"
  fi

  # Print the first line of the prompt
  print -P "$time_stamp $directory$git$py$docker$result"
}

fresh_almostontop() {
  # CSI ESC[6n gets the cursor position in the form ESC[<row>;<column>R
  printf "\033[6n"
  # Discard prefix delimited by [
  read -s -d [
  # Store the <row> delimited by ; in row
  read -s -d \; row
  # Discard suffix delimted by R otherwise it is output to the tty
  read -s -d R
  # Move the cursor to the bottom of the terminal
  # CSI ESC[<num>B moves the cursor down <num> lines
  let "down = $LINES - $row"
  printf "\033[${down}B"
  # Print new lines to push the old command out of view
  let "new = $row - 3"
  for (( i = 0; i < $new; i++ )); do
    printf "\n"
  done
  # Move the cursor to the line below the prompt
  # CSI ESC[<num>A moves the cursor up <num> lines
  let "up = $LINES - 3"
  printf "\033[${up}A"
}

fresh_compile_git_prompt() {
  # Compile a simple C program which parses the output of `git status
  # --procelain` to greatly decrease the time taken to draw the prompt
  [ ! -d ~/.cache/zsh ] && mkdir -p ~/.cache/zsh
  if [ ! -f ~/.cache/zsh/git-prompt ]; then
    cc -std=gnu99 -O3 -DNDEBUG -Wno-unused-result \
      ~/.config/zsh/git-prompt.c -o ~/.cache/zsh/git-prompt
    if [ $? -ne 0 ]; then
      echo "git-prompt was not compiled, is a C99 toolchain installed?"
    fi
  fi
}

prompt_fresh_setup "$@"

# vim:ft=zsh