#!/bin/bash
if ! [[ "$1" =~ ^-?[0-9](\.[0-9]+)?+$ ]]; then
    echo "Usage: $0 <Belter display value (mm)>"
    exit 1
fi

echo "Belter display value: $1mm"

tension=$(awk -v x="$1" 'BEGIN {
    if (x < 0) x = -x
    printf "%.3f", 7.673640167 * x - 33.7167364
}')

echo "Belt tension: $tension N"
echo ""

ESC=$'\033'
GREEN="${ESC}[32m"
RED="${ESC}[31m"
RESET="${ESC}[0m"

check_range() {
    local label="$1"
    local min="$2"
    local max="$3"

    awk -v t="$tension" -v min="$min" -v max="$max" \
        -v label="$label" -v G="$GREEN" -v R="$RED" -v Z="$RESET" '
    BEGIN {
        if (t >= min && t <= max)
            printf "%s 🟩  %s[%.1f, %.1f] N%s\n", label, G, min, max, Z
        else
            printf "%s 🟥  %s[%.1f, %.1f] N%s\n", label, R, min, max, Z
    }'
}

echo "Reference tensions:"
check_range "Voron A/B belts    :" 7.8 15
check_range "Voron 2.4 Z belts  :" 20.4 25.8
check_range "V350/250 belts     :" 12 20
check_range "GT2 belts          :" 20 30