package com.gzzn.omms.msgexchange

import com.gzzn.omms.msgexchange.delivery.Dispatcher
import com.gzzn.omms.msgexchange.ingress.InboxPoller
import com.gzzn.omms.msgexchange.processing.Pump
import com.gzzn.omms.msgexchange.jobs.JobRunner
import io.micronaut.context.annotation.Requires
import io.micronaut.runtime.event.annotation.EventListener
import io.micronaut.runtime.server.event.ServerStartupEvent
import jakarta.annotation.PreDestroy
import jakarta.inject.Singleton

/**
 * 管道的启动与停机：服务起来后拉起 inbox 轮询、主泵、投递三条循环，每条各占一个专用平台线程；
 * 停机时先让它们各自收尾，再中断线程解除 sleep 并等待退出。
 *
 * 只有配置 msgx.pipeline.autostart=true 时才装配，默认不开：得有真实仓储或者 msgx.stubs=true
 * 才能安全自启。
 */
@Requires(property = "msgx.pipeline.autostart", value = "true")
@Singleton
class PipelineLifecycle(
    private val poller: InboxPoller,
    private val pump: Pump,
    private val dispatcher: Dispatcher,
    private val jobRunner: JobRunner,
) {
    private val log = org.slf4j.LoggerFactory.getLogger(PipelineLifecycle::class.java)
    private val threads = mutableListOf<Thread>()

    @Volatile
    private var started = false

    @EventListener
    fun start(event: ServerStartupEvent) {
        startIfNeeded()
    }

    private fun startIfNeeded() {
        if (started) return
        // 管道参数合法性已由 PipelineConfigCheck 在启动时无条件校验（CLM-7）；
        // 这里只负责拉起循环线程。
        started = true
        threads += spawn("msgx-inbox-poller", poller::loop)
        threads += spawn("msgx-pump", pump::loop)
        threads += spawn("msgx-dispatcher", dispatcher::loop)
        jobRunner.start()
        log.info("pipeline loops started (inbox-poller, pump, dispatcher, jobs)")
    }

    private fun spawn(name: String, body: () -> Unit): Thread =
        Thread.ofPlatform().name(name).daemon(true).start { body() }

    @PreDestroy
    fun stop() {
        poller.stop()
        pump.stop()
        dispatcher.stop()
        jobRunner.stop()
        threads.forEach { it.interrupt() }          // 打断 sleep，让循环立刻醒过来退出，而不是干等一轮间隔
        threads.forEach { runCatching { it.join(3000) } }
        log.info("pipeline loops stopped")
    }
}