package metrics

import (
	"log"
	"strconv"
	"strings"
	"time"

	"github.com/shirou/gopsutil/v3/cpu"
	"github.com/shirou/gopsutil/v3/load"
	"github.com/shirou/gopsutil/v3/mem"
	"github.com/wormhole/wormhole/internal/bridge"
	"github.com/wormhole/wormhole/internal/cache"
	"github.com/wormhole/wormhole/internal/store"
)

type Collector struct {
	store  *store.Store
	cache  *cache.Manager
	bridge *bridge.Bridge
	stop   chan struct{}
}

func NewCollector(st *store.Store, c *cache.Manager, b *bridge.Bridge) *Collector {
	return &Collector{
		store:  st,
		cache:  c,
		bridge: b,
		stop:   make(chan struct{}),
	}
}

func (c *Collector) Start(flushInterval time.Duration) {
	go func() {
		ticker := time.NewTicker(flushInterval)
		defer ticker.Stop()
		for {
			select {
			case <-ticker.C:
				c.flushFlow()
			case <-c.stop:
				return
			}
		}
	}()
}

func (c *Collector) Stop() {
	close(c.stop)
}

func (c *Collector) flushFlow() {
	deltas := c.cache.DrainFlow()
	for key, delta := range deltas {
		parts := strings.SplitN(key, ":", 2)
		if len(parts) != 2 {
			continue
		}
		resourceType := parts[0]
		resourceID, err := strconv.ParseUint(parts[1], 10, 64)
		if err != nil {
			continue
		}
		if err := c.store.UpsertFlowStat(resourceType, uint(resourceID), delta.Inlet, delta.Export); err != nil {
			log.Printf("[metrics] flush flow stat: %v", err)
		}
		switch resourceType {
		case "client":
			_ = c.store.AddClientFlow(uint(resourceID), delta.Inlet, delta.Export)
		case "tunnel":
			_ = c.store.AddTunnelFlow(uint(resourceID), delta.Inlet, delta.Export)
		case "host":
			_ = c.store.AddHostFlow(uint(resourceID), delta.Inlet, delta.Export)
		}
	}
}

func (c *Collector) RecordRequestIP(resourceType string, resourceID uint, visitorIP, directIP string) {
	if err := c.store.RecordRequestIP(resourceType, resourceID, visitorIP, directIP); err != nil {
		log.Printf("[metrics] record request ip: %v", err)
	}
}

func (c *Collector) AddFlow(resourceType string, resourceID uint, clientID uint, inlet, export int64) {
	c.cache.AddFlow(resourceType, resourceID, inlet, export)
	if clientID > 0 {
		c.cache.AddFlow("client", clientID, inlet, export)
	}
}

func (c *Collector) Dashboard() (map[string]interface{}, error) {
	stats, err := c.store.DashboardStats()
	if err != nil {
		return nil, err
	}
	stats["client_online"] = c.bridge.OnlineCount()

	cpuPercent, _ := cpu.Percent(0, false)
	memInfo, _ := mem.VirtualMemory()
	loadInfo, _ := load.Avg()

	var cpuVal float64
	if len(cpuPercent) > 0 {
		cpuVal = cpuPercent[0]
	}

	topClients, _ := c.store.TopClientsByFlow(10)
	topTunnels, _ := c.store.TopTunnelsByFlow(10)
	topHosts, _ := c.store.TopHostsByFlow(10)
	topIPs, _ := c.store.TopRequestIPs(10)

	stats["cpu_percent"] = cpuVal
	stats["mem_percent"] = memInfo.UsedPercent
	stats["load1"] = loadInfo.Load1
	stats["top_clients"] = topClients
	stats["top_tunnels"] = topTunnels
	stats["top_hosts"] = topHosts
	stats["top_ips"] = topIPs
	return stats, nil
}