Fancy bash prompt

.bashrc

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

__ps1_git() {
    local B S C c u z
    # If not in working tree return
    git rev-parse --is-inside-work-tree &>/dev/null || return
    B=$(git branch --show-current 2>/dev/null)
    # If there is no branch your are detached
    [[ -z $B ]] && B=$(git rev-parse --short HEAD)
    S=$(git status --porcelain -s 2>/dev/null)
    # Local changes
    [[ $S == ' A'* || $S == ' M'* || $S == ' D'* ]] && c='*'
    # Untracked files
    [[ $S == *'??'* ]] && u='%'
    # Stashed files
    git rev-parse --verify -q refs/stash &>/dev/null && z='$'
    C="$c$u$z"
    [[ -n $C ]] && C=" $C"
    printf '(%s%s)' "$B" "$C"
}

__ps1() {
    history -a
    PROMPT_DIRTRIM=2
    # Sync pwd in vte based terminals
    declare -F __vte_osc7 &>/dev/null && __vte_osc7 2>/dev/null
    local r='\[\e[31m\]' gr='\[\e[0;32m\]' y='\[\e[33m\]' \
        bl='\[\e[34m\]' pu='\[\e[0;35m\]' x='\[\e[0m\]' \
        G E N P C
    has nix && [[ -n $IN_NIX_SHELL || "$PATH" == *'/nix/store'* ]] && N='(nix)'
    has git && G="$(__ps1_git)"
    [ -n "$CONTAINER_ID" ] && C="[$CONTAINER_ID]"
    [ -n "$VIRTUAL_ENV" ] && E="(${VIRTUAL_ENV##*/})"
    P="$gr\u@\h$C$x:$bl\w$pu$N$y$E$r$G$x"
    [ $COLUMNS -gt 80 ] && PS1="$P\$ " || PS1="$P\n\$ "
}

PROMPT_COMMAND="__ps1"