// Package monitor 周期性采集各专线运行状态与流量
package monitor

import (
	"time"

	"vpn-platform/backend/internal/core"
	"vpn-platform/backend/internal/model"
	"vpn-platform/backend/internal/store"
)

// Start 启动状态采集循环（每 15 秒刷新一次）
func Start(mgr *core.Manager, interval time.Duration) {
	if interval == 0 {
		interval = 15 * time.Second
	}
	ticker := time.NewTicker(interval)
	go func() {
		collect(mgr) // 启动即采集一次
		for range ticker.C {
			collect(mgr)
		}
	}()
}

func collect(mgr *core.Manager) {
	var tunnels []model.Tunnel
	if err := store.DB.Find(&tunnels).Error; err != nil {
		return
	}
	for i := range tunnels {
		t := &tunnels[i]
		p, err := mgr.Get(t.Protocol)
		if err != nil {
			continue
		}
		st, err := p.Status(t)
		if err != nil {
			continue
		}
		mgr.SetStatus(t.ID, st)
		// 数据库状态与协议真实状态同步，避免页面长期展示过时的“运行中”。
		if st.State != "" && st.State != t.State {
			store.DB.Model(t).Update("state", st.State)
		}
		// 流量持久化（仅在有增量时写库）
		if st.RxBytes > 0 || st.TxBytes > 0 {
			store.DB.Model(t).Updates(map[string]interface{}{"rx_bytes": st.RxBytes, "tx_bytes": st.TxBytes})
		}
		// 到期自动停止
		if t.ExpireAt != nil && time.Now().After(*t.ExpireAt) && t.State == "running" {
			_ = p.Stop(t)
			store.DB.Model(t).Update("state", "stopped")
		}
	}
}

// AutoStartAll 启动时拉起所有标记为自启的专线
func AutoStartAll(mgr *core.Manager) {
	var tunnels []model.Tunnel
	if err := store.DB.Where("auto_start = ?", true).Find(&tunnels).Error; err != nil {
		return
	}
	for i := range tunnels {
		t := &tunnels[i]
		if p, err := mgr.Get(t.Protocol); err == nil {
			if err := p.Start(t); err != nil {
				store.DB.Model(t).Updates(map[string]interface{}{"state": "error", "last_error": err.Error()})
			} else {
				store.DB.Model(t).Update("state", "running")
			}
		}
	}
}