#!/usr/bin/env bash
# ---
# @file_name: prompt.sh
# @version: 1.0.1
# @description: a prompt
# @author: Jamie Albert (empty_produce)
# @author_contact: <mailto:empty.produce@flatmail.me>
# @license: GNU Affero General Public License v3.0 (Included in LICENSE)
# Copyright (C) 2025, Jamie Albert
# ---

declare -g _cached_uh=""
declare -g _uh_cache_key=""
declare -g _cached_pyenv_version=""
declare -g _pyenv_cache_key=""
declare -g _cached_readonly=""
declare -g _readonly_cache_key=""

# ---
#  Shell options configuration
# ---
shopt -s histappend
shopt -s cmdhist
shopt -s histreedit
shopt -s histverify
shopt -s interactive_comments
shopt -s checkwinsize
shopt -s globstar
shopt -s nocaseglob
shopt -s dirspell
shopt -s cdspell
shopt -u autocd

if [[ $- =~ "i" ]]; then
	bind "set completion-ignore-case on"
	bind "set show-all-if-ambiguous on"
	bind "set mark-symlinked-directories on"
fi

# ---
# * Symbols
# ---
_prompt_symbol="❯"
_git_symbol="git:"
_pyenv_symbol="pyenv:"
_readonly_symbol="ro:"
_screen_symbol="scr:"

# ---
# * Colours
# ---
_prompt_success_colour="142"
_prompt_fail_colour="203"
_prompt_user_colour="109"
_prompt_sudo_colour="208"
_prompt_at_colour="249"
_prompt_hostname_colour="132"
_prompt_info_colour="172"
_prompt_input_colour="254"
_prompt_dir_colour="249"
_git_module_colour="66"
_pyenv_module_colour="66"
_readonly_module_colour="196"
_screen_module_colour="33"

# ---
# * Miscellaneous
# ---
_prompt_hostname="ssh"
_prompt_separator=" "
_prompt_wrapper="[]"

# ---
#  // * Nerd Symbols
# // OBSOLETE 2025-11-07
# ---
# _git_symbol="󰘦"
# _pyenv_symbol="󰌠"
# _readonly_symbol="󰍁"
# _screen_symbol="󰐅"
# _prompt_symbol="󰥭"

# ---
# * Aliases
# ---
alias count='find . -type f | wc -l'
alias cdd='cd /home/jamie/dao'
alias dnf='sudo dnf'
alias hist='history|grep'
alias ll="ls -laFh"
alias la='ls -A'
alias li='la | grep -i'
alias lh='ll -d .*'
alias mkdir='mkdir -p'
alias nano='nano -W'
alias qq='exit'
alias sc='sudo systemctl'
alias xclipc='xclip -sel c'

# ---
# * Environment settings
# ---
declare -g HISTTIMEFORMAT='%F %T '
declare -g PROMPT_DIRTRIM="2"
[[ -z "$LC_CTYPE" && -z "$LC_ALL" ]] && declare -g LC_CTYPE="${LANG%%:*}"
[[ -z "$HISTFILE" ]] && declare -g HISTFILE="$HOME/.bash_history"
declare -x HISTCONTROL=ignorespace
declare -x HISTFILESIZE=10000
declare -x HISTSIZE=${HISTFILESIZE}

# ---
# * colour function
# ---
_prompt_colour() {
	[[ ${1} != "-" ]] && echo -ne "\[\033[38;5;${1}m\]" || echo -ne "\[\033[0m\]"
}

# ---
# * Generate prompt segments
# ---
_prompt_generate() {
	declare _separator="" _text="${1%%|*}" _colour="${1##*|}"
	[[ ${_prompt_seg} -gt 1 ]] && _separator="${_prompt_separator}"
	_prompt_information+="${_separator}$(_prompt_colour "${_colour}")${_text}\[\e[0m\]"
	((_prompt_seg++))
}

# ---
# * Screen
# ---
_screen_pre() {
	[[ ${TERM} == "screen"* ]] && _prompt_generate "${_screen_symbol}|${_screen_module_colour}"
}

# ---
# * Git
# ---
_git_post() {
	[[ -z "$_git_dir" ]] && _git_dir="$(git rev-parse --git-dir 2>/dev/null)"
	[[ -n "$_git_dir" ]] || return

	local _unsafe_ref
	_unsafe_ref=$(git symbolic-ref -q HEAD 2>/dev/null) || return
	local _clean_ref="${_unsafe_ref##refs/heads/}"
	_clean_ref="${_clean_ref//[^a-zA-Z0-9\/]/-}"

	local _status=""
	[[ -n "$(git status --porcelain 2>/dev/null)" ]] && _status="*"
	[[ -n "$(git ls-files --others --exclude-standard 2>/dev/null)" ]] && _status="${_status}+"

	[[ -n ${_clean_ref} ]] && _prompt_generate "${_git_symbol} ${_clean_ref}${_status}|${_git_module_colour}"
}

# ---
# * Pyenv
# ---
_pyenv_post() {
	[[ -n ${VIRTUAL_ENV} ]] || return
	[[ "$VIRTUAL_ENV" != "$_pyenv_cache_key" ]] && {
		_cached_pyenv_version="${PYTHON_VERSION}"
		[[ -z ${_cached_pyenv_version} ]] && _cached_pyenv_version="$(python3 --version 2>/dev/null)"
		_cached_pyenv_version="${_cached_pyenv_version#Python }"
		_pyenv_cache_key="$VIRTUAL_ENV"
	}
	[[ -n ${_cached_pyenv_version} ]] && _prompt_generate "${_prompt_wrapper:0:1}${_pyenv_symbol} ${_cached_pyenv_version}${_prompt_wrapper:1:1}|${_pyenv_module_colour}"
}

# ---
# * Readonly
# ---
_readonly_post() {
	[[ "$PWD" != "$_readonly_cache_key" ]] && {
		_cached_readonly=""
		[[ ! -w "$(pwd)" ]] && _cached_readonly="readonly"
		_readonly_cache_key="$PWD"
	}
	[[ -n "$_cached_readonly" ]] && _prompt_generate "${_prompt_wrapper:0:1}${_readonly_symbol}${_prompt_wrapper:1:1}|${_readonly_module_colour}"
}

# ---
# * Build the main prompt
# ---
_prompt_build() {
	declare _last_status="$?" _gen_uh _cache_key="${PWD}"
	declare -gi _prompt_seg=1

	[[ "$_cache_key" != "$_last_cache_key" ]] && {
		unset _git_dir _cached_pyenv_version
		_last_cache_key="$_cache_key"
	}

	# ---
	# ! Insert *pre* functions here
	# ---
	# START
	_screen_pre
	# END

	# ---
	# * User and hostname
	# ---
	declare _user_colour="${_prompt_user_colour}"
	sudo -nv 2>/dev/null && _user_colour="${_prompt_sudo_colour}"

	_gen_uh="${_cached_uh}"
	_uh_cache_key="${_prompt_hostname}:${SSH_CLIENT:-}:$(sudo -n -v 2>/dev/null && echo 'sudo' || echo 'nosudo')"

	[[ "$_uh_cache_key" != "$_last_uh_key" ]] && {
		_gen_uh="$(_prompt_colour "${_user_colour}")${USER}"

		if [[ ${_prompt_hostname} == "all" ]] || [[ ${_prompt_hostname} == "ssh" && -n ${SSH_CLIENT} ]]; then
			_gen_uh+="$(_prompt_colour "${_prompt_at_colour}")@$(_prompt_colour "${_prompt_hostname_colour}")${HOSTNAME}"
		fi

		_gen_uh+="\[\033[0m\]"
		_cached_uh="$_gen_uh"
		_last_uh_key="$_uh_cache_key"
	}
	_prompt_generate "${_gen_uh}|${_prompt_info_colour}"

	# ---
	# * Current directory
	# ---
	declare _current_dir="${PWD}"
	_current_dir="${_current_dir/#$HOME/\~}"
	_prompt_generate "$(_prompt_colour "${_prompt_info_colour}")${_prompt_wrapper:0:1}$(_prompt_colour "${_prompt_dir_colour}")${_current_dir}$(_prompt_colour "${_prompt_info_colour}")${_prompt_wrapper:1:1}\[\033[0m\]|${_prompt_info_colour}"

	# ---
	# * Error status
	# ---
	[[ ${_last_status} -ne 0 ]] && _prompt_generate "${_prompt_wrapper:0:1}${_last_status}${_prompt_wrapper:1:1}|${_prompt_fail_colour}"

	# ---
	# ! Insert *post* functions here
	# ---
	# START
	_git_post
	_pyenv_post
	_readonly_post

	# END

	# ---
	# *Final prompt symbol
	# ---
	_prompt_status_colour=${_prompt_success_colour}
	[[ ${_last_status} -ne 0 ]] && _prompt_status_colour=${_prompt_fail_colour}
	_prompt_information+="$(_prompt_colour "${_prompt_status_colour}")\n${_prompt_symbol}\[\e[0m\]"
	PS1="${_prompt_information} "
	unset _prompt_information _prompt_seg
}

# ---
# * Initialize prompt
# ---
_prompt_init() {
	case "$PROMPT_COMMAND" in
	*"_prompt_build"*) ;;
	"") PROMPT_COMMAND="_prompt_build" ;;
	*) PROMPT_COMMAND="_prompt_build;${PROMPT_COMMAND}" ;;
	esac
}

# ---
#  * Initialize when sourced
# ---
[[ ${BASH_SOURCE[0]} != "${0}" ]] && _prompt_init