#!/usr/bin/env bash
set -Eeuo pipefail

log() {
  printf '[display-audio] %s\n' "$*"
}

warn() {
  printf '[display-audio] WARN: %s\n' "$*" >&2
  logger -t couch-display-audio -- "$*" 2>/dev/null || true
}

pick_hdmi_refresh() {
  awk '
    $1 == "HDMI-1" && $2 == "connected" { in_hdmi=1; next }
    in_hdmi && $0 !~ /^[[:space:]]/ { exit }
    in_hdmi && $1 == "1920x1080" {
      for (i = 2; i <= NF; i++) {
        gsub(/[+*]/, "", $i)
        if ($i ~ /^[0-9]+(\.[0-9]+)?$/) {
          value = $i + 0
          if (value > best) {
            best = value
            best_text = $i
          }
        }
      }
    }
    END {
      if (best_text != "") {
        print best_text
      }
    }
  '
}

choose_hdmi_profile() {
  pactl list cards | awk '
    /^Card #[0-9]+/ { card="" }
    /^\tName: / { sub(/^\tName: /, "", $0); card=$0 }
    /^\t\toutput:hdmi/ && /available: yes/ {
      profile=$1
      sub(/:$/, "", profile)
      print card "\t" profile
      exit
    }
  '
}

choose_hdmi_sink() {
  pactl list short sinks | awk '$2 ~ /\.hdmi/ { print $2; exit }'
}

xrandr_output="$(xrandr --query)"
if ! grep -q '^HDMI-1 connected' <<<"${xrandr_output}"; then
  warn "HDMI-1 is not connected; deferring display/audio switch"
  exit 0
fi

refresh="$(printf '%s\n' "${xrandr_output}" | pick_hdmi_refresh)"
if [[ -z "${refresh}" ]]; then
  warn "HDMI-1 is connected but no 1920x1080 refresh was discovered"
  exit 0
fi

log "setting HDMI-1 primary at 1920x1080@${refresh} and disabling eDP-1"
xrandr --output HDMI-1 --primary --mode 1920x1080 --rate "${refresh}" --output eDP-1 --off

profile_line="$(choose_hdmi_profile || true)"
if [[ -z "${profile_line}" ]]; then
  warn "HDMI audio sink/profile not available yet; display configured and audio switch deferred"
  exit 0
fi

card_name="${profile_line%%$'\t'*}"
profile_name="${profile_line#*$'\t'}"
log "selecting HDMI audio profile ${profile_name} on ${card_name}"
pactl set-card-profile "${card_name}" "${profile_name}"
pactl list short sinks >/dev/null 2>&1 || true
sink_name="$(choose_hdmi_sink || true)"
if [[ -z "${sink_name}" ]]; then
  warn "HDMI sink still unavailable after profile switch; audio switch deferred"
  exit 0
fi
pactl set-default-sink "${sink_name}"