#!/usr/bin/env bash
# Container entrypoint: run sync.sh once, or in a loop every
# SYNC_INTERVAL_SECONDS. There's no systemd/cron inside the container, so a
# simple sleep-loop is the pragmatic choice.
set -euo pipefail

: "${SYNC_INTERVAL_SECONDS:=3600}"
: "${RUN_ONCE:=false}"

log() { echo "[entrypoint] $(date '+%Y-%m-%d %H:%M:%S') $*"; }

run_once() {
    /usr/local/bin/sync.sh
}

if [[ "$RUN_ONCE" == "true" ]]; then
    log "RUN_ONCE=true - running sync.sh once and exiting"
    run_once
    exit $?
fi

log "Starting sync loop (interval: ${SYNC_INTERVAL_SECONDS}s)"

# Graceful shutdown on docker stop / compose down
term_handler() {
    log "Received SIGTERM, shutting down"
    exit 0
}
trap term_handler SIGTERM SIGINT

while true; do
    # NOTE: don't inline `run_once` into `if ! run_once; then ...`  - inside
    # that then-branch, $? would reflect the (always-0) negated test itself,
    # not run_once's real exit code. Capture it explicitly instead.
    rc=0
    run_once || rc=$?
    if [[ $rc -ne 0 ]]; then
        log "sync.sh failed (exit ${rc}) - will retry after the next interval"
    fi
    log "Sleeping ${SYNC_INTERVAL_SECONDS}s until next sync..."
    sleep "${SYNC_INTERVAL_SECONDS}" &
    wait $!
done