package main

import (
	"archive/tar"
	"compress/gzip"
	"crypto/sha256"
	"encoding/hex"
	"encoding/json"
	"flag"
	"fmt"
	"io"
	"log"
	"net/http"
	"os"
	"os/exec"
	"os/signal"
	"path/filepath"
	"regexp"
	"strconv"
	"strings"
	"syscall"
	"time"
)

type Config struct {
	PauseThreshold  float64 `json:"pause_threshold"`
	ResumeThreshold float64 `json:"resume_threshold"`
	MaxCPUUsage     int     `json:"max_cpu_usage"`
	XMRigPath       string  `json:"xmrig_path"`
	CPUPriority     int     `json:"cpu_priority"`
	AutoUpdate      bool    `json:"auto_update"`
	ForceUpdate     bool    `json:"force_update"`
	SkipUpdateCheck bool    `json:"skip_update_check"`
	LogFile         string  `json:"log_file"`
	Verbose         bool    `json:"verbose"`
}

type MinerManager struct {
	Config     Config
	IsRunning  bool
	MinerCmd   *exec.Cmd
	MinerPID   int
	LastStats  CPUStats
}

type CPUStats struct {
	User   uint64
	Nice   uint64
	System uint64
	Idle   uint64
	Total  uint64
}

var httpClient = &http.Client{Timeout: 30 * time.Second}

func main() {
	config := parseFlags()
	
	err := ensureXMRigBinary(&config)
	if err != nil {
		log.Fatalf("Failed to ensure XMRig binary: %v", err)
	}

	manager := &MinerManager{
		Config: config,
	}

	sigChan := make(chan os.Signal, 1)
	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)

	go func() {
		<-sigChan
		fmt.Println("\nStopping miner and exiting...")
		manager.stopMiner()
		os.Exit(0)
	}()

	fmt.Println("=== XMRig Idle Manager ===")
	manager.monitorAndManage()
}

func parseFlags() Config {
	var c Config
	flag.Float64Var(&c.PauseThreshold, "pause-threshold", 30.0, "CPU percentage to pause mining")
	flag.Float64Var(&c.ResumeThreshold, "resume-threshold", 15.0, "CPU percentage to resume mining")
	flag.IntVar(&c.MaxCPUUsage, "max-cpu-usage", 75, "Maximum CPU usage for XMRig")
	flag.StringVar(&c.XMRigPath, "xmrig-path", "", "Override XMRig binary location")
	flag.IntVar(&c.CPUPriority, "cpu-priority", 0, "CPU priority (0-5)")
	flag.BoolVar(&c.AutoUpdate, "auto-update", false, "Automatically download XMRig updates")
	flag.BoolVar(&c.ForceUpdate, "force-update", false, "Force update XMRig")
	flag.BoolVar(&c.SkipUpdateCheck, "skip-update-check", false, "Skip checking for XMRig updates")
	flag.StringVar(&c.LogFile, "log-file", "/tmp/xmrig.log", "Log file path")
	flag.BoolVar(&c.Verbose, "verbose", false, "Enable verbose logging")
	flag.Parse()
	return c
}

func ensureXMRigBinary(c *Config) error {
	if c.XMRigPath != "" {
		if _, err := os.Stat(c.XMRigPath); err != nil {
			return fmt.Errorf("specified XMRig path not found: %s", c.XMRigPath)
		}
		fmt.Printf("Using user-specified XMRig: %s\n", c.XMRigPath)
		return nil
	}

	path := findXMRigBinary()
	if path == "" {
		fmt.Println("XMRig binary not found. Downloading...")
		return downloadAndInstallXMRig(c)
	}
	
	c.XMRigPath = path
	if !c.SkipUpdateCheck {
		checkAndUpdateXMRig(c)
	}
	return nil
}

func findXMRigBinary() string {
	paths := []string{"./xmrig", "/usr/bin/xmrig", expandPath("~/.local/bin/xmrig")}
	for _, p := range paths {
		if _, err := os.Stat(p); err == nil {
			return p
		}
	}
	return ""
}

func expandPath(path string) string {
	if strings.HasPrefix(path, "~/") {
		return filepath.Join(os.Getenv("HOME"), path[2:])
	}
	return path
}

func (m *MinerManager) monitorAndManage() {
	ticker := time.NewTicker(5 * time.Second)
	for range ticker.C {
		usage, err := m.getCPUUsage()
		if err != nil {
			fmt.Printf("Error during monitoring: %v\n", err)
			continue
		}

		if usage > m.Config.PauseThreshold && m.IsRunning {
			fmt.Printf("CPU high (%.1f%%). Pausing miner...\n", usage)
			m.stopMiner()
		} else if usage < m.Config.ResumeThreshold && !m.IsRunning {
			fmt.Printf("CPU low (%.1f%%). Resuming miner...\n", usage)
			m.startMiner()
		}
	}
}

func (m *MinerManager) getCPUUsage() (float64, error) {
	stats1, err := readCPUStat()
	if err != nil {
		return 0, err
	}
	time.Sleep(1 * time.Second)
	stats2, err := readCPUStat()
	if err != nil {
		return 0, err
	}

	idle := float64(stats2.Idle - stats1.Idle)
	total := float64(stats2.Total - stats1.Total)
	if total == 0 { return 0, nil }
	return (1.0 - idle/total) * 100.0, nil
}

func readCPUStat() (CPUStats, error) {
	f, err := os.Open("/proc/stat")
	if err != nil {
		return CPUStats{}, err
	}
	defer f.Close()

	var cpu string
	var user, nice, system, idle, iowait, irq, softirq, steal, guest, guestnice uint64
	_, err = fmt.Fscanf(f, "%s %d %d %d %d %d %d %d %d %d %d", &cpu, &user, &nice, &system, &idle, &iowait, &irq, &softirq, &steal, &guest, &guestnice)
	if err != nil {
		return CPUStats{}, err
	}

	total := user + nice + system + idle + iowait + irq + softirq + steal
	return CPUStats{user, nice, system, idle, total}, nil
}

func (m *MinerManager) startMiner() error {
	args := []string{
		"-o", "pool.gravitywell.xyz:11666",
		"-u", "48p7c...",
		"--cpu-max-threads-hint", strconv.Itoa(m.Config.MaxCPUUsage),
	}
	
	m.MinerCmd = exec.Command(m.Config.XMRigPath, args...)
	m.MinerCmd.Stdout = os.Stdout
	m.MinerCmd.Stderr = os.Stderr
	
	if err := m.MinerCmd.Start(); err != nil {
		return fmt.Errorf("failed to start miner: %w", err)
	}
	
	m.MinerPID = m.MinerCmd.Process.Pid
	m.IsRunning = true
	return nil
}

func (m *MinerManager) stopMiner() {
	if m.MinerCmd != nil && m.MinerCmd.Process != nil {
		m.MinerCmd.Process.Signal(syscall.SIGTERM)
		m.MinerCmd.Wait()
	}
	m.IsRunning = false
}

func checkAndUpdateXMRig(c *Config) {}
func downloadAndInstallXMRig(c *Config) error { return nil }
func downloadFile(url string, path string) error { return nil }
func verifyChecksum(path string, checksum string) error { return nil }
func extractTarGz(src string, dest string) error { return nil }
func copyFile(src string, dest string) error { return nil }
func getLatestXMRigRelease() (string, string, error) { return "", "", nil }
func getXMRigVersion(path string) (string, error) { return "", nil }
func extractChecksum(data []byte, filename string) (string, error) { return "", nil }