#!/usr/bin/env bash
# scripts/daemon/lesavka-uvc.sh - launch UVC control helper as a standalone service
set -euo pipefail

# Optional env file for runtime overrides (debug, width/fps, etc.)
if [[ -r /etc/lesavka/uvc.env ]]; then
    # shellcheck disable=SC1091
    source /etc/lesavka/uvc.env
fi

resolve_default_uvc_dev() {
    local ctrl=""
    ctrl=$(ls /sys/class/udc 2>/dev/null | head -n1 || true)
    if [[ -n $ctrl ]]; then
        printf '/dev/v4l/by-path/platform-%s-video-index0\n' "$ctrl"
        return 0
    fi
    local candidate=""
    candidate=$(ls /dev/v4l/by-path/platform-*-video-index0 2>/dev/null | head -n1 || true)
    [[ -n $candidate ]] || return 1
    printf '%s\n' "$candidate"
}

wait_for_uvc_dev() {
    local dev="$1"
    for _ in {1..50}; do
        [[ -e $dev ]] && return 0
        sleep 0.1
    done
    return 1
}

if [[ -n ${LESAVKA_UVC_DEV:-} ]]; then
    DEV=${LESAVKA_UVC_DEV}
else
    DEV=$(resolve_default_uvc_dev || true)
fi

if [[ -z ${DEV:-} ]]; then
    echo "[lesavka-uvc] no gadget video_output node discovered; waiting for /dev/v4l/by-path/platform-*-video-index0 or set LESAVKA_UVC_DEV" >&2
    exit 1
fi

if ! wait_for_uvc_dev "$DEV"; then
    echo "[lesavka-uvc] gadget video_output node is still absent: $DEV" >&2
    exit 1
fi

exec /usr/local/bin/lesavka-uvc --device "$DEV"