bashui/bashui

#!/usr/bin/env bash

# GLOBALS

declare UI_CROW UI_CCOL USER_INPUT

# TERMINAL AND CURSOR INFO

term_size() case $1 in
    c) echo $(tput cols)
       ;;
    l) echo $(tput lines)
       ;;
    *) echo $(tput lines) $(tput cols)
esac

cursor_position() {
    echo $UI_CROW $UI_CCOL
}

cursor_line() {
    echo $UI_CROW
}

cursor_col() {
    echo $UI_CCOL
}

# CURSOR POSITION

cursor_set() {
    UI_CROW=$1
    UI_CCOL=$2
    tput cup $UI_CROW $UI_CCOL
}

cmove_top() {
    UI_CROW=0
    UI_CCOL=${1:-0}
    cursor_set $UI_CROW $UI_CCOL
}

cmove_bottom() {
    UI_CROW=$(( $(term_size l) - 1 ))
    UI_CCOL=${1:-0}
    cursor_set $UI_CROW $UI_CCOL
}

cmove_row() {
    UI_CROW=$1
    cursor_set $UI_CROW $UI_CCOL
}

cmove_col() {
    UI_CCOL=$1
    cursor_set $UI_CROW $UI_CCOL
}

cmove_up() {
    local mv
    mv=${1:-1}
    : $((UI_CROW - $mv))
    UI_CROW=$(( $_ >= 0 ? (UI_CROW - mv) : 0  ))
    cmove_row $UI_CROW
}

cmove_down() {
    local mv limit
    mv=${1:-1}
    limit=$(($(term_size l) - 1))
    : $((UI_CROW + $mv))
    UI_CROW=$(( $_ < limit ? (UI_CROW + mv) : limit ))
    cmove_row $UI_CROW
}

cmove_left() {
    local mv
    mv=${1:-1}
    : $((UI_CCOL - $mv))
    UI_CCOL=$(( $_ >= 0 ? (UI_CCOL - mv) : 0  ))
    cmove_col $UI_CCOL
}

cmove_right() {
    local mv limit
    mv=${1:-1}
    limit=$(($(term_size c) - 1))
    : $((UI_CCOL + $mv))
    UI_CCOL=$(( $_ < limit ? (UI_CCOL + mv) : limit ))
    cmove_col $UI_CCOL
}

cmove_home() {
    UI_CCOL=0
    cmove_col $UI_CCOL
}

cmove_end() {
    UI_CCOL=$(($(term_size c) - 1))
    cmove_col $UI_CCOL
}

# CLEAR TERMINAL, LINE AND REGION

clear_terminal() {
    clear
    UI_CROW=0
    UI_CCOL=0
}

clear_line() {
    UI_CROW=${1:-$(cursor_line)}
    cursor_set $UI_CROW 0
    tput el
}

clear_region() {
    local row col width height fill line

    row=$1
    col=$2
    width=$3
    height=$((row + $4 - 1))

    printf -v fill "%${width}s" ''

    for line in $(seq -s ' ' $row $height ); do
	cursor_set $line $col
	printf '%s' "$fill"
    done
}

# FRAMES AND WINDOWS

draw_frame() {
    local row col width height fill line

    row=$1
    col=$2
    width=$3
    height=$((row + $4 - 2))

    printf -v fill "%$((width - 2))s" ''

    cursor_set $row $col
    printf '%s' "┌${fill// /─}┐"
    ((row++))
    for line in $(seq -s ' ' $row $height ); do
	cursor_set $line $col
	printf '%s' "│${fill}│"
	((row++))
    done
    cursor_set $row $col
    printf '%s' "└${fill// /─}┘"
}

draw_title_bar() {
    local fill
    printf -v fill "%$(($3 - 2))s" ''
    cursor_set $(( $1 + 2 )) $2
    printf '%s' "├${fill// /─}┤"
}

draw_status_bar() {
    local fill
    printf -v fill "%$(($3 - 2))s" ''
    cursor_set $(($1 + $4 - 3)) $2
    printf '%s' "├${fill// /─}┤"
}

# STRINGS

print_label() {
    local str align col_start col_end column line_width len

    str="$1"
    len=$(str_len "$str")
    col_start=0
    col_end=$(term_size c)
    align=left

    case $# in
	2)  if in_string 'left right center' "$2"; then
		align=$2
	    else
		col_start=${2%,*}
		col_end=${2#*,}
	    fi
	    ;;
	3)  align=$2
	    col_start=${3%,*}
	    col_end=$((${3#*,} + 1))
	    ;;
    esac

    line_width=$(( col_end - col_start ))

    case $align in
    	  left) column=$col_start;;
	 right) column=$((col_start + line_width - len));;
	center) column=$((col_start + ((line_width - len) / 2) ));;
    esac

    cursor_set $UI_CROW $column
    printf '%s' "$str"
}

str_len() {
    echo "${#1}"
}

in_string() [[ "$1" == *"$2"* ]]

# WIDGETS

input_bar() {
    local prompt position border line

    prompt="$1"
    position=bottom
    border=1
    line=$(($(term_size l) - 3))

    case $# in
	2) in_string 'top bottom' "$2" && position=$2 || border=$2;;
	3) position=$2; border=$3;;
    esac

    if ((border)); then
	[[ $position = top ]] && line=0
	draw_frame $line 0 $(term_size c) 3
	cmove_up
	cmove_right 2
    else
	case $position in
	    top) cmove_top 1;;
	    bottom) cmove_bottom 1;;
	esac
    fi

    read -rep "$prompt " USER_INPUT
}