#!/bin/bash

# Get primary display name
display=$(xrandr --query | awk '/ connected primary/{print $1}')

# If no primary, use first connected
if [ -z "$display" ]; then
    display=$(xrandr --query | awk '/ connected/{print $1; exit}')
fi

if [ -z "$display" ]; then
    echo "No connected display found."
    exit 1
fi

# Get physical dimensions line for that display
dim_line=$(xrandr --query | grep "^$display connected")

# Extract width and height in mm
width_mm=$(echo "$dim_line" | sed -n 's/.* \([0-9]\+\)mm x \([0-9]\+\)mm.*/\1/p')
height_mm=$(echo "$dim_line" | sed -n 's/.* \([0-9]\+\)mm x \([0-9]\+\)mm.*/\2/p')

if [ -z "$width_mm" ] || [ -z "$height_mm" ]; then
    echo "Could not determine physical screen size."
    exit 1
fi

# Calculate diagonal in mm
diagonal_mm=$(echo "scale=4; sqrt($width_mm^2 + $height_mm^2)" | bc -l)

# Convert to inches
diagonal_in=$(echo "scale=2; $diagonal_mm / 25.4" | bc -l)
return ${diagonal_in%.*}