#!/usr/bin/env bash
# Generate ~/.config/sway/config.d/05-outputs.conf from the monitors sway sees right now.
# Laptop panel first (left), the rest follow to the right. Run inside a sway session.
# Usage: outputs-setup.sh [--auto]    (--auto: no questions, guess scales)
set -euo pipefail

AUTO=0; [ "${1:-}" = "--auto" ] && AUTO=1
OUT=${XDG_CONFIG_HOME:-$HOME/.config}/sway/config.d/05-outputs.conf

command -v swaymsg >/dev/null && [ -n "${SWAYSOCK:-}" ] || { echo "Run this inside a sway session." >&2; exit 1; }
command -v python3 >/dev/null || { echo "python3 is required." >&2; exit 1; }

mapfile -t ROWS < <(swaymsg -t get_outputs -r | python3 -c '
import json,sys
outs=[o for o in json.load(sys.stdin) if o.get("active") or o.get("power", True)]
# internal panels (eDP/LVDS/DSI) first, then the others by name
outs.sort(key=lambda o:(0 if o["name"].startswith(("eDP","LVDS","DSI")) else 1, o["name"]))
for o in outs:
    m=o.get("current_mode") or {}
    print(o["name"], m.get("width",0), m.get("height",0), o.get("make","?").replace(" ","_"), o.get("model","?").replace(" ","_"))
')
[ "${#ROWS[@]}" -gt 0 ] || { echo "No outputs found." >&2; exit 1; }

guess_scale() {  # name width height
    case $1 in
        eDP*|LVDS*|DSI*)
            if   [ "$2" -ge 3000 ]; then echo 2
            elif [ "$2" -ge 2400 ]; then echo 1.5
            elif [ "$2" -ge 1900 ] && [ "$3" -ge 1200 ]; then echo 1.25
            else echo 1; fi ;;
        *) echo 1 ;;
    esac
}

x=0; body=""
for row in "${ROWS[@]}"; do
    read -r name w h make model <<<"$row"
    scale=$(guess_scale "$name" "$w" "$h")
    if [ "$AUTO" = 0 ]; then
        read -r -p "$name ($make $model, ${w}x${h}) scale [$scale]: " ans || ans=""
        [ -n "$ans" ] && scale=$ans
    fi
    body+="output $name position $x 0 scale $scale"$'\n'
    x=$(python3 -c "print(int($x + $w / $scale))")
done

mkdir -p "$(dirname "$OUT")"
[ -e "$OUT" ] && cp -a "$OUT" "$OUT.bak"
{
    echo "# Monitor layout, generated by outputs-setup.sh (edit freely; re-run to regenerate)"
    printf '%s' "$body"
} > "$OUT"
echo "Wrote $OUT:"; cat "$OUT"
swaymsg reload >/dev/null && echo "sway reloaded."