package nodes

import (
	"encoding/json"
	"log"
	"os"
	"runtime"
	"strconv"
	"strings"
	"time"

	"github.com/TeaOSLab/EdgeCommon/pkg/nodeconfigs"
	"github.com/TeaOSLab/EdgeCommon/pkg/rpc/pb"
	"github.com/TeaOSLab/EdgeHttpDNS/internal/configs"
	teaconst "github.com/TeaOSLab/EdgeHttpDNS/internal/const"
	"github.com/TeaOSLab/EdgeHttpDNS/internal/rpc"
	"github.com/TeaOSLab/EdgeHttpDNS/internal/utils"
	"github.com/iwind/TeaGo/maps"
	"github.com/shirou/gopsutil/v3/cpu"
	"github.com/shirou/gopsutil/v3/mem"
)

type StatusManager struct {
	quitCh <-chan struct{}
	ticker *time.Ticker

	isFirstTime      bool
	cpuUpdatedTime   time.Time
	cpuLogicalCount  int
	cpuPhysicalCount int
}

func NewStatusManager(quitCh <-chan struct{}) *StatusManager {
	return &StatusManager{
		quitCh:          quitCh,
		ticker:          time.NewTicker(30 * time.Second),
		isFirstTime:     true,
		cpuUpdatedTime:  time.Now(),
		cpuLogicalCount: runtime.NumCPU(),
	}
}

func (m *StatusManager) Start() {
	defer m.ticker.Stop()

	m.update()
	for {
		select {
		case <-m.ticker.C:
			m.update()
		case <-m.quitCh:
			return
		}
	}
}

func (m *StatusManager) update() {
	status := m.collectStatus()
	statusJSON, err := json.Marshal(status)
	if err != nil {
		log.Println("[HTTPDNS_NODE][status]marshal status failed:", err.Error())
		return
	}

	rpcClient, err := rpc.SharedRPC()
	if err != nil {
		log.Println("[HTTPDNS_NODE][status]rpc unavailable:", err.Error())
		return
	}

	config, err := configs.SharedAPIConfig()
	if err != nil {
		log.Println("[HTTPDNS_NODE][status]load config failed:", err.Error())
		return
	}
	nodeId, _ := strconv.ParseInt(config.NodeId, 10, 64)

	_, err = rpcClient.HTTPDNSNodeRPC.UpdateHTTPDNSNodeStatus(rpcClient.Context(), &pb.UpdateHTTPDNSNodeStatusRequest{
		NodeId:      nodeId,
		IsUp:        true,
		IsInstalled: true,
		IsActive:    true,
		StatusJSON:  statusJSON,
	})
	if err != nil {
		log.Println("[HTTPDNS_NODE][status]update status failed:", err.Error())
	}

	m.reportNodeValues(rpcClient, status)
	m.isFirstTime = false
}

func (m *StatusManager) collectStatus() *nodeconfigs.NodeStatus {
	now := time.Now().Unix()

	status := &nodeconfigs.NodeStatus{
		BuildVersion:     teaconst.Version,
		BuildVersionCode: utils.VersionToLong(teaconst.Version),
		ConfigVersion:    0,
		OS:               runtime.GOOS,
		Arch:             runtime.GOARCH,
		CPULogicalCount:  m.cpuLogicalCount,
		CPUPhysicalCount: m.cpuPhysicalCount,
		IsActive:         true,
		ConnectionCount:  0,
		UpdatedAt:        now,
		Timestamp:        now,
	}

	rpcClient, err := rpc.SharedRPC()
	if err == nil {
		total, failed, avgCostSeconds := rpcClient.GetAndResetMetrics()
		if total > 0 {
			status.APISuccessPercent = float64(total-failed) * 100.0 / float64(total)
			status.APIAvgCostSeconds = avgCostSeconds
		}
	}

	hostname, _ := os.Hostname()
	status.Hostname = hostname

	exePath, _ := os.Executable()
	status.ExePath = exePath

	m.updateCPU(status)
	m.updateMemory(status)
	m.updateLoad(status)

	return status
}

func (m *StatusManager) updateCPU(status *nodeconfigs.NodeStatus) {
	duration := time.Duration(0)
	if m.isFirstTime {
		duration = 100 * time.Millisecond
	}

	percents, err := cpu.Percent(duration, false)
	if err == nil && len(percents) > 0 {
		status.CPUUsage = percents[0] / 100
	}

	if time.Since(m.cpuUpdatedTime) >= 5*time.Minute || m.cpuLogicalCount <= 0 {
		m.cpuUpdatedTime = time.Now()

		if logicalCount, countErr := cpu.Counts(true); countErr == nil && logicalCount > 0 {
			m.cpuLogicalCount = logicalCount
		}
		if physicalCount, countErr := cpu.Counts(false); countErr == nil && physicalCount > 0 {
			m.cpuPhysicalCount = physicalCount
		}
	}

	status.CPULogicalCount = m.cpuLogicalCount
	if m.cpuPhysicalCount > 0 {
		status.CPUPhysicalCount = m.cpuPhysicalCount
	}
}

func (m *StatusManager) updateMemory(status *nodeconfigs.NodeStatus) {
	stat, err := mem.VirtualMemory()
	if err != nil || stat == nil || stat.Total == 0 {
		return
	}

	usedBytes := stat.Used
	if stat.Total > stat.Free+stat.Buffers+stat.Cached {
		usedBytes = stat.Total - stat.Free - stat.Buffers - stat.Cached
	}

	status.MemoryTotal = stat.Total
	status.MemoryUsage = float64(usedBytes) / float64(stat.Total)
}

func (m *StatusManager) updateLoad(status *nodeconfigs.NodeStatus) {
	load1m, load5m, load15m := readLoadAvg()
	status.Load1m = load1m
	status.Load5m = load5m
	status.Load15m = load15m
}

func (m *StatusManager) reportNodeValues(rpcClient *rpc.RPCClient, status *nodeconfigs.NodeStatus) {
	if rpcClient == nil || status == nil {
		return
	}

	m.createNodeValue(rpcClient, nodeconfigs.NodeValueItemCPU, maps.Map{
		"usage": status.CPUUsage,
		"cores": status.CPULogicalCount,
	})
	m.createNodeValue(rpcClient, nodeconfigs.NodeValueItemMemory, maps.Map{
		"usage": status.MemoryUsage,
		"total": status.MemoryTotal,
	})
	m.createNodeValue(rpcClient, nodeconfigs.NodeValueItemLoad, maps.Map{
		"load1m":  status.Load1m,
		"load5m":  status.Load5m,
		"load15m": status.Load15m,
	})
}

func (m *StatusManager) createNodeValue(rpcClient *rpc.RPCClient, item string, value maps.Map) {
	valueJSON, err := json.Marshal(value)
	if err != nil {
		log.Println("[HTTPDNS_NODE][status]marshal node value failed:", err.Error())
		return
	}

	_, err = rpcClient.NodeValueRPC.CreateNodeValue(rpcClient.Context(), &pb.CreateNodeValueRequest{
		Item:      item,
		ValueJSON: valueJSON,
		CreatedAt: time.Now().Unix(),
	})
	if err != nil {
		log.Println("[HTTPDNS_NODE][status]create node value failed:", item, err.Error())
	}
}

func readLoadAvg() (float64, float64, float64) {
	data, err := os.ReadFile("/proc/loadavg")
	if err != nil {
		return 0, 0, 0
	}

	parts := strings.Fields(strings.TrimSpace(string(data)))
	if len(parts) < 3 {
		return 0, 0, 0
	}

	load1m, _ := strconv.ParseFloat(parts[0], 64)
	load5m, _ := strconv.ParseFloat(parts[1], 64)
	load15m, _ := strconv.ParseFloat(parts[2], 64)
	return load1m, load5m, load15m
}