# Shared helpers for arranging outputs and routing workspaces across both
# machines: the laptop (whatever external display happens to be plugged
# in, if any) and the desktop (a fixed DP-3/DP-2 pair). Sourced by
# apply-outputs.sh and select-workspace.sh so both always agree on which
# output is "primary" and in what order the rest follow.

is_laptop() {
  local supply
  for supply in /sys/class/power_supply/*/; do
    [[ -r "${supply}type" ]] || continue
    [[ "$(<"${supply}type")" == Battery ]] && return 0
  done
  return 1
}

is_internal_panel() {
  case "$1" in
    eDP-*|LVDS-*|DSI-*) return 0 ;;
    *) return 1 ;;
  esac
}

# Prints the names of currently active outputs, one per line, ordered
# primary-first:
#   - laptop:  any external display(s), in the order sway reports them,
#              then the internal panel last (so a docked external is
#              always primary; undocked, the panel is the only entry).
#   - desktop: DP-3, then DP-2, then anything else alphabetically as a
#              fallback for an unexpected output.
output_order() {
  local outputs_json name
  outputs_json=$(swaymsg -t get_outputs -r)
  mapfile -t active < <(jq -r '.[] | select(.active) | .name' <<<"$outputs_json")

  local ordered=()
  if is_laptop; then
    local externals=() internals=()
    for name in "${active[@]}"; do
      if is_internal_panel "$name"; then internals+=("$name"); else externals+=("$name"); fi
    done
    ordered=("${externals[@]}" "${internals[@]}")
  else
    local preferred=(DP-3 DP-2) p seen
    for p in "${preferred[@]}"; do
      for name in "${active[@]}"; do [[ "$name" == "$p" ]] && ordered+=("$name"); done
    done
    for name in "${active[@]}"; do
      seen=false
      local o
      for o in "${ordered[@]}"; do [[ "$o" == "$name" ]] && seen=true; done
      "$seen" || ordered+=("$name")
    done
  fi
  printf '%s\n' "${ordered[@]}"
}