package main

import (
	"context"
	"log"
	"time"

	"knowledge-governance/internal/appconfig"
	"knowledge-governance/internal/libraryexecutor"
	postgresstore "knowledge-governance/internal/platform/postgres"
)

// 为什么由 worker 观测、页面读库：agent socket 只挂载在 worker 容器里，API 那个
// LIBRARY_AGENT_SOCKET 即使配了也 dial 不到。谁真能执行就由谁写下观测，
// 否则页面上的"可发起"只是配置字符串的回声。
const libraryExecutorProbeInterval = 30 * time.Second

// libraryExecutorProbeTimeout 是一次 health 往返的上限：它只是同 uid unix socket
// 上的一次 JSON 往返，慢到秒级就说明执行器有问题，不该拖住心跳。
const libraryExecutorProbeTimeout = 3 * time.Second

func recordLibraryExecutorStatus(ctx context.Context, store *postgresstore.Store, config appconfig.Config) {
	// 归属用**封存源**实例：agent 冻结的是源库写入者，和同步目标（kgseal）不是一套。
	instance := config.SourceInstance()
	if instance == "" {
		// 没有实例身份，观测就无处归属：写进去只会让页面拿别的实例的状态。
		log.Print("library executor probe skipped: LIBRARY_SOURCE_INSTANCE is not configured")
		return
	}
	observation := libraryexecutor.Probe(ctx, instance, config.LibraryAgentSocket, libraryExecutorProbeTimeout, nil)
	if err := store.UpsertLibraryExecutorStatus(ctx, observation, config.WorkerID, time.Now().UTC()); err != nil {
		log.Printf("library executor status not recorded: %v", err)
	}
}

// runLibraryExecutorProbe 先观测一次再进循环：页面在 worker 刚起来时就该有真实状态。
func runLibraryExecutorProbe(ctx context.Context, store *postgresstore.Store, config appconfig.Config, interval time.Duration) {
	if interval <= 0 {
		interval = libraryExecutorProbeInterval
	}
	recordLibraryExecutorStatus(ctx, store, config)
	ticker := time.NewTicker(interval)
	defer ticker.Stop()
	for {
		select {
		case <-ctx.Done():
			return
		case <-ticker.C:
			recordLibraryExecutorStatus(ctx, store, config)
		}
	}
}