#!/usr/bin/env bash
# Invoked by Sunshine as a stream-stop hook (global_prep_cmd `undo`).
# Moves the previously-active workspace back to a real monitor (if any
# exist) and tears down the headless output created by sunshine-stream-do.sh.

set -euo pipefail

log() { printf '[sunshine-undo] %s\n' "$*" >&2; }

STATE_DIR="${XDG_RUNTIME_DIR:-/tmp}/sunshine-headless"
# Headless name was captured by sunshine-stream-do.sh; fall back to discovery.
MON="$(cat "$STATE_DIR/headless-name" 2>/dev/null || true)"

if ! command -v hyprctl >/dev/null 2>&1; then
  log "hyprctl not found; nothing to undo."
  exit 0
fi

if [[ -z "${HYPRLAND_INSTANCE_SIGNATURE:-}" ]]; then
  for sig_dir in "${XDG_RUNTIME_DIR:-/tmp}"/hypr/*/; do
    [[ -d "$sig_dir" ]] || continue
    export HYPRLAND_INSTANCE_SIGNATURE="$(basename "$sig_dir")"
    break
  done
  if [[ -z "${HYPRLAND_INSTANCE_SIGNATURE:-}" ]]; then
    log "Hyprland not running; nothing to undo."
    exit 0
  fi
fi

PREV_WS="$(cat "$STATE_DIR/prev-workspace-id" 2>/dev/null || echo 1)"

if [[ -z "$MON" ]]; then
  MON="$(hyprctl monitors -j 2>/dev/null \
    | jq -r '.[] | select(.name | startswith("HEADLESS")) | .name' | head -1)"
fi

# Find a non-headless monitor to move the workspace back to. If there isn't one
# (truly headless host with KVM detached), the workspace just lives on whatever
# Hyprland reassigns it to when we remove the output.
REAL_MON="$(hyprctl monitors -j 2>/dev/null | jq -r '.[] | select(.name | test("^HEADLESS") | not) | .name' | head -n1)"
if [[ -n "$REAL_MON" ]]; then
  log "Returning workspace $PREV_WS → $REAL_MON"
  hyprctl dispatch moveworkspacetomonitor "$PREV_WS $REAL_MON" >/dev/null || true
  hyprctl dispatch focusmonitor "$REAL_MON" >/dev/null || true
else
  log "No real monitor connected; leaving workspace assignment to Hyprland defaults."
fi

# Leave HEADLESS-1 in place. It needs to exist persistently for Sunshine's
# encoder probe to succeed at startup; removing-and-recreating per session
# raced with the probe and caused fatal startup errors. Resizing on each
# new client (in sunshine-stream-do.sh) is enough — the output itself stays.

# Clean state files but keep the directory for the next run.
rm -f "$STATE_DIR/prev-monitors.json" "$STATE_DIR/prev-workspace-id"
log "Stream teardown complete (HEADLESS-1 kept for next connect)"