shell-terminfo

#!/bin/sh -efu
### This file is covered by the GNU General Public License,
### which should be included with libshell as the file LICENSE.
### All copyright information are listed in the COPYING.

if [ -z "${__included_shell_terminfo-}" ]; then
__included_shell_terminfo=1

. shell-error

COLUMNS=80
LINES=25

color_black=7
color_blue=7
color_green=7
color_cyan=7
color_red=7
color_magenta=7
color_yellow=7
color_white=7

__terminfo_setup_caps()
{
	set \
		setbg:setab \
		setbg:setb \
		setfg:setaf \
		setfg:setf \
		bold:bold \
		sitm:sitm \
		smul:smul \
		rev:rev \
		hpa:hpa \
		vpa:vpa \
		ritm:ritm \
		rmul:rmul \
		op:op \
		sgr0:sgr0 \
	;
	local cap_pair var cap

	for cap_pair; do
		var="${cap_pair%:*}"
		eval "__terminfo_cap_$var=''"
	done

	for cap_pair; do
		var="${cap_pair%:*}"
		cap="${cap_pair#*:}"
		eval "
		__terminfo_cap_$var=\"\${__terminfo_cap_$var-}\";
		! tput $cap >/dev/null 2>&1 ||
			__terminfo_cap_$var='$cap';
		[ -n \"\$__terminfo_cap_$var\" ] ||
			verbose \"Capability '$cap' is not defined for this terminal.\""
	done
}

__terminfo_setup_colors()
{
	local order name i=0

	[ "$__terminfo_cap_setfg" = 'setf' ] &&
		order='black blue green cyan red magenta yellow white' ||
		order='black red green yellow blue magenta cyan white'

	for name in $order; do
		eval "color_$name=$i"
		i=$(($i + 1))
	done
}

### Usage: terminfo_init [force]
# shellcheck disable=SC2120
terminfo_init()
{
	[ -z "${__terminfo_init-}" ] || [ "${1-}" = force ] ||
		return 0

	type tput >/dev/null 2>&1 ||
		fatal "Unable to find \`tput' utility."

	[ -n "${TERM-}" ] || TERM=dumb
	export TERM

	local cols rows
	cols="$(tput cols)"  && export COLUMNS="$cols" || return
	rows="$(tput lines)" && export LINES="$rows"   || return

	__terminfo_setup_caps
	__terminfo_setup_colors

	__terminfo_init=1
}

### Usage: terminfo_color_pattern <begin|end> pattern
###
### Pattern format: [[type] [modificator] color]
###
### type        := {foreground|background} or {fg|bg}
###	modificator := {bold|italic|underline|reverse} or {b|i|u|rev}
### color       := {black|blue|green|cyan|red|magenta|yellow|white}
terminfo_color_pattern()
{
	local c ctype='fg' color
	local color_bg='' color_fg='' bold='' italic='' uline='' reverse=''

	for c in $2; do
		case "$c" in
			fg|foreground)
				ctype='fg'
				;;
			bg|background)
				ctype='bg'
				;;
			rev|reverse)
				reverse=1
				;;
			b|bold)
				bold=1
				;;
			i|italic)
				italic=1
				;;
			u|underline)
				uline=1
				;;
			black|blue|green|cyan|red|magenta|yellow|white)
				eval "[ -z \"\${__terminfo_cap_set$ctype-}\" ] || color_$ctype=\"\$color_$c\""
				;;
			*)
				fatal "Unknown color: $c"
				;;
		esac
	done

	case "$1" in
		b|begin)
			tput -S <<EOF
${reverse:+$__terminfo_cap_rev
}${bold:+$__terminfo_cap_bold
}${italic:+$__terminfo_cap_sitm
}${uline:+$__terminfo_cap_smul
}${color_fg:+$__terminfo_cap_setfg $color_fg
}${color_bg:+$__terminfo_cap_setbg $color_bg
}
EOF
			;;
		e|end)
			tput -S <<EOF
${italic:+$__terminfo_cap_ritm
}${uline:+$__terminfo_cap_rmul
}${__terminfo_cap_op:+$__terminfo_cap_op
}${__terminfo_cap_sgr0:+$__terminfo_cap_sgr0
}
EOF
			;;
		*)
			fatal "Unknown type: $1"
			;;
	esac
}

### Usage: terminfo_col number
terminfo_col()
{
	# shellcheck disable=SC2119
	terminfo_init
	if [ -n "${COLUMNS-}" ] && [ "$1" -ge "${COLUMNS:-0}" ]; then
		message "value must be less than $COLUMNS"
		return 1
	fi
	[ -n "${__terminfo_cap_hpa-}" ] ||
		message "Capability 'hpa' is not defined for this terminal."
	tput "$__terminfo_cap_hpa" "$1"
}

### Usage: terminfo_row number
terminfo_row()
{
	# shellcheck disable=SC2119
	terminfo_init
	[ -n "${__terminfo_cap_vpa-}" ] ||
		message "Capability 'vpa' is not defined for this terminal."
	tput "$__terminfo_cap_vpa" "$1"
}

### Usage: color_text text [pattern]
color_text()
{
	# shellcheck disable=SC2119
	terminfo_init
	terminfo_color_pattern b "$2" || return
	printf '%s' "$1"
	terminfo_color_pattern e "$2" || return
}

### Usage: color_message text [pattern]
color_message()
{
	color_text "$@" || return
	printf '\n'
}

fi #__included_shell_terminfo