command_prompt.bash

# A modern, informative and configurable command prompt for the Bash shell.
#
# URL:     github.com/bluz71/bash-seafly-prompt
# License: MIT (https://opensource.org/licenses/MIT)


# Non-interactive shells don't have a prompt, exit early.
[[ $- =~ i ]] || return 0

# Set a simple prompt for non-256color, non-alacritty and non-kitty terminals.
if [[ $TERM != *-256color ]] && [[ $TERM != alacritty* ]] && [[ $TERM != *-kitty ]]; then
    PS1='\h \w > '
    return 0
fi

# Default colors used in the prompt.
: ${SEAFLY_PREFIX_COLOR:="\e[38;5;217m"}
: ${SEAFLY_SUCCESS_COLOR:=$(echo -ne '\e[38;5;111m')}
: ${SEAFLY_ALERT_COLOR:=$(echo -ne '\e[38;5;203m')}
: ${SEAFLY_HOST_COLOR:="\e[38;5;255m"}
: ${SEAFLY_GIT_COLOR:="\e[38;5;147m"}
: ${SEAFLY_PATH_COLOR:="\e[38;5;114m"}
: ${NOCOLOR:=$(echo -ne '\e[m')}

# Shorten directory paths to a maximum of four components unless PROMPT_DIRTRIM
# has already been set.
: ${PROMPT_DIRTRIM:=4}

# Default Git indicator values.
: ${GIT_PS1_SHOWDIRTYSTATE:=1}
: ${GIT_PS1_SHOWSTASHSTATE:=1}
: ${GIT_PS1_SHOWUPSTREAM:=1}

# Default layout settings.
: ${SEAFLY_LAYOUT:=1}
: ${SEAFLY_MULTILINE:=0}
: ${SEAFLY_SHOW_USER:=0}
: ${SEAFLY_SHOW_HOST:=1}
: ${SEAFLY_SHOW_USERHOST_CONNECTED:=1}

# Default symbols used in the prompt.
: ${SEAFLY_PROMPT_SYMBOL:="❯"}
: ${SEAFLY_PS2_PROMPT_SYMBOL:="❯"}
: ${SEAFLY_GIT_PREFIX:=" "}
: ${SEAFLY_GIT_SUFFIX:=""}
: ${SEAFLY_GIT_DIRTY:="✗"}
: ${SEAFLY_GIT_STAGED:="✓"}
: ${SEAFLY_GIT_STASH:="⚑"}
: ${SEAFLY_GIT_AHEAD:="↑"}
: ${SEAFLY_GIT_BEHIND:="↓"}
: ${SEAFLY_GIT_DIVERGED:="↕"}

# Collate Git details using either the
# [git-status-fly](https://github.com/bluz71/git-status-fly) or
# [git-status-snap](https://github.com/bluz71/git-status-snap) utilities.
#
_seafly_git_status_parser() {
    if (( SEAFLY_GIT_STATUS_FLY == 1 )); then
        . <(git-status-fly)
    else
        . <(git-status-snap)
    fi
    [[ -z "$GSF_REPOSITORY" ]] && return

    # We are in a Git repository.
    local branch=$GSF_BRANCH
    if [[ $branch == "HEAD" ]]; then
        branch="detached*$(git rev-parse --short HEAD 2>/dev/null)"
    fi
    branch=${branch//\\/\\\\} # Escape backslashes
    branch=${branch//\$/\\\$} # Escape dollars
    local ellipsis="…" # Truncate, with ellipsis, long branch names
    branch="${branch:0:30}${ellipsis:0:$(( ${#branch} > 30 ))}"

    local dirty
    local staged
    if [[ $branch != "detached*" &&
          $GIT_PS1_SHOWDIRTYSTATE -ne 0 &&
          $(git config --bool bash.showDirtyState) != "false" ]]; then
        [[ -n $GSF_DIRTY ]] && dirty=$SEAFLY_GIT_DIRTY
        [[ -n $GSF_STAGED ]] && staged=$SEAFLY_GIT_STAGED
    fi

    local stash
    if [[ $GIT_PS1_SHOWSTASHSTATE -ne 0 ]]; then
        [[ -n $GSF_STASH ]] && stash=$SEAFLY_GIT_STASH
    fi

    local upstream
    if [[ $GIT_PS1_SHOWUPSTREAM -ne 0 && -n $GSF_UPSTREAM ]]; then
        if (( GSF_UPSTREAM == 2 )); then
            upstream=$SEAFLY_GIT_DIVERGED
        elif (( GSF_UPSTREAM == 1 )); then
            upstream=$SEAFLY_GIT_AHEAD
        elif (( GSF_UPSTREAM < 0 )); then
            upstream=$SEAFLY_GIT_BEHIND
        elif (( GSF_UPSTREAM == 0 )); then
            upstream="="
        fi
    fi

    local spacer
    if [[ -n $dirty || -n $staged || -n $stash || -n $upstream ]]; then
        spacer=" "
    fi
    _seafly_git="$SEAFLY_GIT_PREFIX$branch$spacer\[$SEAFLY_ALERT_COLOR\]$dirty\[$SEAFLY_SUCCESS_COLOR\]$staged$upstream\[$SEAFLY_GIT_COLOR\]$stash$SEAFLY_GIT_SUFFIX "
}

# Collate Git details using just the 'git' command.
#
_seafly_git_command() {
    local is_git_repo
    if [[ $(git rev-parse --is-inside-work-tree --is-bare-repository 2>/dev/null) =~ true ]]; then
        is_git_repo=1
    fi
    (( is_git_repo == 1 )) || return

    # We are in a Git repository.
    local branch="$(git rev-parse --abbrev-ref HEAD 2>/dev/null)"
    if [[ $branch == "HEAD" ]]; then
        branch="detached*$(git rev-parse --short HEAD 2>/dev/null)"
    fi
    branch=${branch//\\/\\\\} # Escape backslashes
    branch=${branch//\$/\\\$} # Escape dollars
    local ellipsis="…" # Truncate, with ellipsis, long branch names
    branch="${branch:0:30}${ellipsis:0:$(( ${#branch} > 30 ))}"

    local dirty
    local staged
    if [[ $branch != "detached*" &&
          $GIT_PS1_SHOWDIRTYSTATE -ne 0 &&
          $(git config --bool bash.showDirtyState) != "false" ]]; then
        git diff --no-ext-diff --quiet --exit-code --ignore-submodules 2>/dev/null || dirty=$SEAFLY_GIT_DIRTY
        git diff --no-ext-diff --quiet --cached --exit-code --ignore-submodules 2>/dev/null || staged=$SEAFLY_GIT_STAGED
    fi

    local stash
    if [[ $GIT_PS1_SHOWSTASHSTATE -ne 0 ]]; then
        git rev-parse --verify --quiet refs/stash >/dev/null && stash=$SEAFLY_GIT_STASH
    fi

    local upstream
    if [[ $GIT_PS1_SHOWUPSTREAM -ne 0 ]]; then
        case "$(git rev-list --left-right --count HEAD...@'{u}' 2>/dev/null)" in
        "") # no upstream
            upstream="" ;;
        "0	0") # equal to upstream
            upstream="=" ;;
        "0	"*) # behind upstream
            upstream=$SEAFLY_GIT_BEHIND ;;
        *"	0") # ahead of upstream
            upstream=$SEAFLY_GIT_AHEAD ;;
        *)	    # diverged from upstream
            upstream=$SEAFLY_GIT_DIVERGED ;;
        esac
    fi

    local spacer
    if [[ -n $dirty || -n $staged || -n $stash || -n $upstream ]]; then
        spacer=" "
    fi
    _seafly_git="$SEAFLY_GIT_PREFIX$branch$spacer\[$SEAFLY_ALERT_COLOR\]$dirty\[$SEAFLY_SUCCESS_COLOR\]$staged$upstream\[$SEAFLY_GIT_COLOR\]$stash$SEAFLY_GIT_SUFFIX "
}

_seafly_command_prompt() {
    # Run the pre-command hook if it is set, if not set this will evaluate to a
    # no-op.
    "${seafly_pre_command_hook-:}"

    local prompt_prefix
    # Run and save the output from the prompt-prefix hook if it is set, if not
    # set prefix-value will evaluate to a no-op.
    local prefix_value=$("${seafly_prompt_prefix_hook-:}")
    if [[ -n $prefix_value ]]; then
        prompt_prefix="\[$SEAFLY_PREFIX_COLOR\]$prefix_value "
    fi
    if (( SEAFLY_MULTILINE == 1 )); then
        prompt_prefix="\n$prompt_prefix"
    fi

    local prompt_start
    if [[ $SEAFLY_SHOW_USERHOST_CONNECTED -eq 0 ]] || [[ $SEAFLY_SHOW_USERHOST_CONNECTED -eq 1 && -n $SSH_CONNECTION ]]; then
        if [[ $SEAFLY_SHOW_USER -eq 1 && $SEAFLY_SHOW_HOST -eq 1 ]]; then
            prompt_start="\[$SEAFLY_HOST_COLOR\]\u@\h "
        elif (( SEAFLY_SHOW_USER == 1 )); then
            prompt_start="\[$SEAFLY_HOST_COLOR\]\u "
        elif (( SEAFLY_SHOW_HOST == 1 )); then
            prompt_start="\[$SEAFLY_HOST_COLOR\]\h "
        fi
    fi

    # Collate Git details, if applicable, for the current directory.
    if (( SEAFLY_GIT_STATUS_FLY == 1 || SEAFLY_GIT_STATUS_SNAP == 1 )); then
        # Use either git-status-fly or git-status-snap utilities.
        _seafly_git_status_parser
    else
       # Use the fallback 'git' command, this will be much slower.
        _seafly_git_command
    fi

    local prompt_middle
    if (( SEAFLY_LAYOUT == 1 )); then
        prompt_middle="\[$SEAFLY_PATH_COLOR\]\w\[$SEAFLY_GIT_COLOR\] $_seafly_git"
    else
        prompt_middle="\[$SEAFLY_GIT_COLOR\]$_seafly_git\[$SEAFLY_PATH_COLOR\]\w "
    fi
    unset _seafly_git

    # Success prompt symbol color indicates that the last command ran
    # without issue whilst alert prompt symbol color indicates that the last
    # command failed.
    _seafly_colors=("$SEAFLY_ALERT_COLOR" "$SEAFLY_SUCCESS_COLOR")

    local prompt_end="\[\${_seafly_colors[\$((!\$?))]}\]$SEAFLY_PROMPT_SYMBOL\[\$NOCOLOR\] "
    if (( SEAFLY_MULTILINE == 1 )); then
        prompt_end="\n$prompt_end"
    fi

    PS1="$prompt_prefix$prompt_start$prompt_middle$prompt_end"
    PS2="\[$SEAFLY_SUCCESS_COLOR\]$SEAFLY_PS2_PROMPT_SYMBOL\[\$NOCOLOR\] "
}

# Use [git-status-fly](https://github.com/bluz71/git-status-fly) if it is
# available.
if [[ -x $(command -v git-status-fly 2>/dev/null) ]]; then
    export SEAFLY_GIT_STATUS_FLY=1
elif [[ -x $(command -v git-status-snap 2>/dev/null) ]]; then
    export SEAFLY_GIT_STATUS_SNAP=1
fi

# Bind and call the '_seafly_command_prompt' function as the Bash prompt.
PROMPT_COMMAND=_seafly_command_prompt