#!/usr/bin/env sh

# SPDX-License-Identifier: AGPL-3.0-or-later

set -eu

is_positive_int() {
    case "${1:-}" in
        '' | 0* | *[!0-9]*) return 1 ;;
        *) [ "$1" -gt 0 ] ;;
    esac
}

available_cpu_count() {
    cpu_quota=""
    cpu_period=""
    if [ -r /sys/fs/cgroup/cpu.max ]; then
        read -r cpu_quota cpu_period < /sys/fs/cgroup/cpu.max || true
    else
        for cgroup_dir in /sys/fs/cgroup/cpu /sys/fs/cgroup/cpu,cpuacct; do
            if [ -r "$cgroup_dir/cpu.cfs_quota_us" ] && [ -r "$cgroup_dir/cpu.cfs_period_us" ]; then
                read -r cpu_quota < "$cgroup_dir/cpu.cfs_quota_us" || true
                read -r cpu_period < "$cgroup_dir/cpu.cfs_period_us" || true
                break
            fi
        done
    fi
    if is_positive_int "$cpu_quota" && is_positive_int "$cpu_period"; then
        echo "$(((cpu_quota + cpu_period - 1) / cpu_period))"
        return 0
    fi
    cpu_count="$(nproc 2>/dev/null || echo 1)"
    if is_positive_int "$cpu_count"; then
        echo "$cpu_count"
    else
        echo 1
    fi
}

: "${FLUXER_ERLANG_NODE_NAME:=fluxer_gateway@127.0.0.1}"
: "${FLUXER_ERLANG_COOKIE:=fluxer_gateway_dev_cookie}"
: "${FLUXER_ERLANG_DIST_PORT:=8081}"

if ! is_positive_int "${FLUXER_ERLANG_SCHEDULERS:-}"; then
    FLUXER_ERLANG_SCHEDULERS="$(available_cpu_count)"
fi

if ! is_positive_int "${FLUXER_ERLANG_DIRTY_CPU_SCHEDULERS:-}"; then
    FLUXER_ERLANG_DIRTY_CPU_SCHEDULERS="$(((FLUXER_ERLANG_SCHEDULERS * 2 + 2) / 3))"
fi

export FLUXER_ERLANG_NODE_NAME
export FLUXER_ERLANG_COOKIE
export FLUXER_ERLANG_DIST_PORT
export FLUXER_ERLANG_SCHEDULERS
export FLUXER_ERLANG_DIRTY_CPU_SCHEDULERS
export RELX_REPLACE_OS_VARS="${RELX_REPLACE_OS_VARS:-true}"

exec /opt/fluxer_gateway/bin/fluxer_gateway foreground