#!/usr/bin/env bash
# Sunshine global_prep_cmd `do` hook for the Sway-based headless capture path
# (Debian/Ubuntu installs where Hyprland isn't available).
#
# On client connect:
#   - Ensures a HEADLESS-1 output exists on the running sway session
#   - Resizes it to the client's negotiated mode (WxH@FPS)
#   - Snapshots state for the undo hook
#
# Sunshine env vars set on connect:
#   SUNSHINE_CLIENT_WIDTH, SUNSHINE_CLIENT_HEIGHT, SUNSHINE_CLIENT_FPS
#
# This script intentionally mirrors the Hyprland do-hook's shape so debugging
# transfers across the two paths.

set -uo pipefail

WIDTH="${SUNSHINE_CLIENT_WIDTH:-1920}"
HEIGHT="${SUNSHINE_CLIENT_HEIGHT:-1080}"
FPS="${SUNSHINE_CLIENT_FPS:-60}"
HEADLESS_NAME="${OMARCHY_VIRTUAL_OUTPUT:-HEADLESS-1}"
STATE_DIR="${XDG_RUNTIME_DIR:-/tmp}/sunshine-headless"
mkdir -p "$STATE_DIR"

HOOK_LOG="$STATE_DIR/hook.log"
: > "$HOOK_LOG"
log() {
  local msg
  msg="$(date +%H:%M:%S.%3N) [sunshine-do-sway] $*"
  printf '%s\n' "$msg" >&2
  printf '%s\n' "$msg" >> "$HOOK_LOG"
}
log "do-hook start: client=${WIDTH}x${HEIGHT}@${FPS} target=${HEADLESS_NAME}"

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

# Recover SWAYSOCK if the unit env didn't propagate it. sway writes the socket
# path into a predictable /run/user/$UID location, but the env var is the
# clean handle.
if [[ -z "${SWAYSOCK:-}" ]]; then
  for sock in "${XDG_RUNTIME_DIR:-/run/user/$(id -u)}"/sway-ipc.*.sock; do
    [[ -S "$sock" ]] || continue
    export SWAYSOCK="$sock"
    log "Discovered SWAYSOCK=$SWAYSOCK"
    break
  done
  if [[ -z "${SWAYSOCK:-}" ]]; then
    log "sway not running (no IPC socket found); nothing to configure."
    exit 0
  fi
fi

# True if an output named $HEADLESS_NAME currently exists on the session.
_headless_present() {
  swaymsg -t get_outputs -r 2>/dev/null \
    | jq -e --arg n "$HEADLESS_NAME" '.[] | select(.name == $n)' >/dev/null
}

# Create the headless output if missing. Sway's `create_output` accepts an
# optional name; without one it auto-assigns HEADLESS-N like Hyprland does.
if ! _headless_present; then
  log "Creating headless output $HEADLESS_NAME"
  if ! swaymsg create_output "$HEADLESS_NAME" >/dev/null 2>&1; then
    # Older sway versions ignore the name argument; fall back and rename via
    # output detection after the fact.
    swaymsg create_output >/dev/null 2>&1 || true
  fi
  # Poll briefly for the output to appear.
  for _ in 1 2 3 4 5; do
    _headless_present && break
    sleep 0.1
  done
  if ! _headless_present; then
    # Last-ditch: take the highest-numbered HEADLESS-* that exists and treat
    # it as ours. Update HEADLESS_NAME in-memory so the resize below targets it.
    found="$(swaymsg -t get_outputs -r 2>/dev/null \
      | jq -r '[.[].name | select(startswith("HEADLESS-"))] | sort_by(.) | last // empty')"
    if [[ -n "$found" ]]; then
      HEADLESS_NAME="$found"
      log "Adopted existing headless output: $HEADLESS_NAME"
    else
      log "Failed to create a headless output; stream will rely on whatever Sunshine selects."
      exit 0
    fi
  fi
fi

# Snapshot state so undo can put things back. We don't move workspaces around
# on a headless-only box (there is no other monitor), but we still record what
# was active in case the user runs sway with a real display attached.
swaymsg -t get_outputs -r > "$STATE_DIR/prev-outputs.json" 2>/dev/null || true
echo "$HEADLESS_NAME" > "$STATE_DIR/headless-name"

# Resize the headless output. Sway accepts mode strings as "WIDTHxHEIGHT@FPSHz".
log "Sizing $HEADLESS_NAME → ${WIDTH}x${HEIGHT}@${FPS}Hz"
if ! swaymsg output "$HEADLESS_NAME" mode "${WIDTH}x${HEIGHT}@${FPS}Hz" >/dev/null 2>&1; then
  log "Mode set with refresh rate failed; retrying without refresh"
  swaymsg output "$HEADLESS_NAME" mode "${WIDTH}x${HEIGHT}" >/dev/null 2>&1 || \
    log "Mode set failed; sway will keep the previous mode."
fi

# Focus the headless output so window placement lands there.
swaymsg focus output "$HEADLESS_NAME" >/dev/null 2>&1 || true

post="$(swaymsg -t get_outputs -r 2>/dev/null \
  | jq -r '.[] | "\(.name) \(.current_mode.width)x\(.current_mode.height)@\(.current_mode.refresh) focused=\(.focused)"' \
  | tr '\n' ';' || true)"
log "post-state outputs: $post"
log "Stream ready: ${WIDTH}x${HEIGHT}@${FPS} on $HEADLESS_NAME"