miniprompt

#!/bin/bash
# shellcheck disable=2154
# shellcheck disable=2034

# --> metadata
config="$([ -z "${XDG_CONFIG_HOME}" ] && echo "${HOME}/.config" || echo "${XDG_CONFIG_HOME}")/miniprompt/conf.toml"

# clrs
declare -A clrs=(
    ["spc"]=' '
    ["nc"]='\[\033[0m\]'

    # normal
    ["gray"]='\[\033[0;30m\]'
    ["red"]='\[\033[0;31m\]'
    ["green"]='\[\033[0;32m\]'
    ["blue"]='\[\033[0;34m\]'
    ["cyan"]='\[\033[0;36m\]'
    ["yellow"]='\[\033[0;33m\]'
    ["magenta"]='\[\033[0;35m\]'
    ["white"]='\[\033[0;37m\]'

    # bright
    ["gray_br"]='\[\033[1;30m\]'
    ["red_br"]='\[\033[1;31m\]'
    ["green_br"]='\[\033[1;32m\]'
    ["blue_br"]='\[\033[1;34m\]'
    ["cyan_br"]='\[\033[1;36m\]'
    ["yellow_br"]='\[\033[1;33m\]'
    ["magenta_br"]='\[\033[1;35m\]'
    ["white_br"]='\[\033[1;37m\]'

    # dim
    ["gray_dm"]='\[\033[2;30m\]'
    ["red_dm"]='\[\033[2;31m\]'
    ["green_dm"]='\[\033[2;32m\]'
    ["blue_dm"]='\[\033[2;34m\]'
    ["cyan_dm"]='\[\033[2;36m\]'
    ["yellow_dm"]='\[\033[2;33m\]'
    ["magenta_dm"]='\[\033[2;35m\]'
    ["white_dm"]='\[\033[2;37m\]'

    # italic
    ["gray_it"]='\[\033[3;30m\]'
    ["red_it"]='\[\033[3;31m\]'
    ["green_it"]='\[\033[3;32m\]'
    ["blue_it"]='\[\033[3;34m\]'
    ["cyan_it"]='\[\033[3;36m\]'
    ["yellow_it"]='\[\033[3;33m\]'
    ["magenta_it"]='\[\033[3;35m\]'
    ["white_it"]='\[\033[3;37m\]'

    # underlined
    ["gray_un"]='\[\033[4;30m\]'
    ["red_un"]='\[\033[4;31m\]'
    ["green_un"]='\[\033[4;32m\]'
    ["blue_un"]='\[\033[4;34m\]'
    ["cyan_un"]='\[\033[4;36m\]'
    ["yellow_un"]='\[\033[4;33m\]'
    ["magenta_un"]='\[\033[4;35m\]'
    ["white_un"]='\[\033[4;37m\]'

    # blinking
    ["gray_bl"]='\[\033[5;30m\]'
    ["red_bl"]='\[\033[5;31m\]'
    ["green_bl"]='\[\033[5;32m\]'
    ["blue_bl"]='\[\033[5;34m\]'
    ["cyan_bl"]='\[\033[5;36m\]'
    ["yellow_bl"]='\[\033[5;33m\]'
    ["magenta_bl"]='\[\033[5;35m\]'
    ["white_bl"]='\[\033[5;37m\]'

    # reversed
    ["gray_re"]='\[\033[7;30m\]'
    ["red_re"]='\[\033[7;31m\]'
    ["green_re"]='\[\033[7;32m\]'
    ["blue_re"]='\[\033[7;34m\]'
    ["cyan_re"]='\[\033[7;36m\]'
    ["yellow_re"]='\[\033[7;33m\]'
    ["magenta_re"]='\[\033[7;35m\]'
    ["white_re"]='\[\033[7;37m\]'
)

declare -A final_extensions=(
    ["git"]=''
    ["ssh"]=''
    ["package"]=''
    ["ip"]=''
    ["wifi"]=''
    ["kube"]=''
)

# help
script_help=$(
    cat <<EOF

MiniPrompt is a minimal and versatile prompt suitable for any type of machine.
You can also use it to toggle extensions on and off 'on the fly'!

Args:
	gt, git							handle the git extension
	sh, ssh							handle the ssh extension
	pk, package						handle the package extension
	ip								handle the ip extension
	wf, wifi						handle the wifi extension
	kb, kube, kubernetes			handle the kubernetes extensions

Modifiers for the args:
	t, toggle						Toggle extension on and off
	e, enable						Enable extension
	d, disable						Disable extension

Flags:
    -h,--help                                   See this help message.
EOF
)

function load_defualt_settings() {
    # behaviour
    colored_exit_status="true"
    dirtrim=2
    enhance_utocompletion="true"
    enhanced_history_format="true"
    dircolors="true"

    # primary_prompt
    prefix="\[\e]0;\w\a\]"
    ps_content="</yellow>\w</nc> "
    ps_suffix="</green>➜</nc> "
    normal_color="nc"
    error_symbol="✗"
    failed="red"

    # extensions
	ext_git="false"
	ext_ssh="false"
	ext_package="false"
	ext_kubernetes="false"
	ext_ip="false"
	ext_wifi="false"
	git_struct="</cyan> </unit> "
	ssh_struct="</magenta> </unit> "
	package_struct="</white> v</unit> "
	ip_struct="</gray_br>  </unit> "
	wifi_struct="</blue>直 </unit> "
	hierarchy="ssh, git, ip, wifi, package"
}

function load_config() {
    load_defualt_settings
    [[ -f $1 ]] || {
        return 1
    }
    entry_regex="^[[:blank:]]*([[:alpha:]_][[:alnum:]_-]*)[[:blank:]]*=[[:blank:]]*('[^']+'|\"[^\"]+\"|[^#[:blank:]]+)[[:blank:]]*(#.*)*$"
    while read -r line; do
        [[ -n $line ]] || continue
        [[ $line =~ $entry_regex ]] || continue
        key=${BASH_REMATCH[1]}
        value=${BASH_REMATCH[2]#[\'\"]} # strip quotes
        value=${value%[\'\"]}
        declare -g "${key}"="${value}"
    done <"$1"
}

function export_ps1_vars() {
    export PS1_previous_exit
    export PS1_prefix
    export PS1_content
    export PS1_suffix
}

function enhance_autocompletion() {
    if [[ "$enhanced_autocompletion" == "true" ]]; then
        bind 'set colored-stats on'
        bind 'set colored-completion-prefix on'
        bind 'set completion-ignore-case on'
        bind 'set completion-map-case on'
        bind 'set expand-tilde on'
        bind 'set mark-directories on'
        bind 'set mark-symlinked-directories on'
        bind 'set show-all-if-ambiguous on'
        bind 'set show-all-if-unmodified on'
        bind 'set skip-completed-text on'
        shopt -s 'cdspell'
        shopt -s 'checkwinsize'
        shopt -s 'dirspell'
    fi
}

function enhance_history_format() {
    if [[ "$enhanced_history_format" == "true" ]]; then
        export HISTCONTROL='ignoreboth:erasedups'
        export HISTTIMEFORMAT='[%Y-%m-%d %T] '
        shopt -s 'histappend'
    fi
}

function load_dircolors() {
    if [[ "$dircolors" == "true" ]]; then
        if [ -x "$(command -v dircolors)" ]; then
            if [ -r "$HOME/.dircolors" ]; then
                eval "$(dircolors -b "$HOME/.dircolors")"
            else
                eval "$(dircolors -b)"
            fi
        fi
    fi
}

function reset_prompt() {
    PS1_previous_exit="$?"
    PS1_prefix="${prefix}" # window title
    for clr in "${!clrs[@]}"; do
        ps_content=${ps_content//"</${clr}>"/"${clrs[$clr]}"}
        ps_suffix=${ps_suffix//"</${clr}>"/"${clrs[$clr]}"}
    done
    PS1_content="${ps_content}"
    PS1_suffix="${ps_suffix}${clrs[$normal_color]}"
}

function clean_variables() {
    unset PS1_prefix \
        PS1_content \
        PS1_suffix \
        PS1_previous_exit
}

function assert_extension() {
    name=$1
    enabled=$2

    if [[ "$enabled" == "true" ]]; then
        unit=""
        case "$name" in
        "git")
            bin_cmd="$(command -v ${name})"
            if [[ "$($bin_cmd rev-parse --is-inside-work-tree 2>/dev/null)" = 'true' ]]; then
                unit=$($bin_cmd branch --show-current)
            fi
            ;;
        "package")
            if [[ -f "package.json" ]]; then # npm
                unit=$(sed 's/.*"version": "\(.*\)".*/\1/;t;d' ./package.json)
            fi
            ;;
        "ssh")
            if [[ -n "$SSH_CONNECTION" ]]; then
                unit="\u@\h"
            fi
            ;;
        "ip")
            IFACE=$(ip -4 route | grep default | head -n1 | awk '{print $5}')
            if [ ! -z "${IFACE}" ]; then
				unit=$(ip -4 -o addr show scope global "${IFACE}" | awk '{gsub(/\/.*/, "",$4); print $4}' | paste -s -d "")
            fi
            ;;
        "wifi")
			unit=$(nmcli -t -f name connection show --active)
            ;;
        "kube")
            bin_cmd="$(command -v ${name})"
            local context
            local namespace
            context="$(${bin_cmd} config view -o=jsonpath='{.current-context}')"
            namespace="$(${bin_cmd} config view -o=jsonpath="{.contexts[?(@.name==\"${context}\")].context.namespace}")"
            PS1_content="${PS1_content:-} ${kube_symbol}\[\e[34m\]${context}${namespace:+:$namespace}\[\e[0m\]"
            ;;
        esac

        if ! [ -z "${unit}" ]; then
            val="${name}_struct"
            parsed_struct="${!val}"
            for clr in "${!clrs[@]}"; do parsed_struct=${parsed_struct//"</${clr}>"/"${clrs[$clr]}"}; done
            final_extensions[${name}]="${parsed_struct//"</unit>"/"${unit}"}"
        else
            final_extensions[${name}]=""
        fi
    fi
}

function turn_ext() {
    task=$1
    var=$2
    if [[ "${task}" == "e" ]] || [[ "${task}" == "enable" ]]; then
        echo "true"
    elif [[ "${task}" == "d" ]] || [[ "${task}" == "disable" ]]; then
        echo "false"
    elif [[ "${task}" == "t" ]] || [[ "${task}" == "toggle" ]]; then
        if [[ "${var}" == "false" ]]; then echo "true"; fi
        echo "false"
    fi
}

function on_da_fly() {
    extension=$1
    task=$2

    case "$extension" in
    "gt" | "git")
        var="ext_git"
        export ${var}="$(turn_ext "${task}" "${var}")"
        ;;
    "sh" | "ssh")
        var="ext_ssh"
        export ${var}="$(turn_ext "${task}" "${var}")"
        ;;
    "pk" | "package")
        var="ext_package"
        export ${var}="$(turn_ext "${task}" "${var}")"
        ;;
    "ip")
        var="ext_ip"
        export ${var}="$(turn_ext "${task}" "${var}")"
        ;;
    "wf" | "wifi")
        var="ext_wifi"
        export ${var}="$(turn_ext "${task}" "${var}")"
        ;;
    "kp" | "kube" | "kubernetes")
        var="ext_kubernetes"
        export ${var}="$(turn_ext "${task}" "${var}")"
        ;;
    "-h" | "--help")
        echo "$script_help"
        # exit 0    # causes shell to close
        ;;
    *)
        echo "Error: command was not recognized"
        ;;
    esac
}

function pre_prompt() {
    export_ps1_vars
    IFS=', ' read -r -a order <<<"$hierarchy"
    for name in "${!final_extensions[@]}"; do # append arbitrarily the missing extensions
        if ! [[ ${order[*]} =~ ${name} ]]; then
            order[${#order[@]}]="${name}"
        fi
    done
    PROMPT_DIRTRIM=${dirtrim}
}

function append_extensions() {
    prompt_extensions=""
    for ((i = 0; i < ${#order[@]}; i++)); do
        if ! [ -z "${final_extensions[${order[$i]}]}" ]; then
            prompt_extensions="${prompt_extensions}${final_extensions[${order[$i]}]}"
        fi
    done
    PS1_content="${PS1_content:-}${prompt_extensions}${clrs[$normal_color]}"
}

function assert_extensions() {
    assert_extension "git" "${ext_git}"
    assert_extension "ssh" "${ext_ssh}"
    assert_extension "package" "${ext_package}"
    assert_extension "ip" "${ext_ip}"
    assert_extension "wifi" "${ext_wifi}"
    # assert_extension "kubectl" "${ext_kubernetes}"
}

function make_behaviour() {
    if [[ "$colored_exit_status" == "true" ]]; then
        [ "$PS1_previous_exit" -ne 0 ] && PS1_suffix="${clrs[$failed]}${error_symbol} ${clrs[$normal_color]}"
    fi
}

function make_prompt() {
    reset_prompt

    make_behaviour
    assert_extensions
    append_extensions

    export PS1="${PS1_prefix:-}${PS1_content:-}${PS1_suffix:-}"
    history -a
    clean_variables
}

function post_prompt() {
    enhance_autocompletion
    enhance_history_format
    load_dircolors
}

main() {
    if [[ ! "$#" > 0 ]]; then
        load_config "${config}"
        pre_prompt
        export PROMPT_COMMAND="make_prompt;$PROMPT_COMMAND"
        post_prompt
    else
        on_da_fly "${1}" "${2}"
    fi
}

main "$@"