package native

import (
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"time"

	"git.sechpoint.app/customer-engineering/wallarm/internal/state"
)

const (
	BaseDir  = "/opt/fw"
	DeployTo = "/opt/wallarm" // setup.sh hardcodes this, deploy here then move
)

func installerURL() string {
	if u := os.Getenv("WALLARM_INSTALLER_URL"); u != "" {
		return u
	}
	return "https://storage.googleapis.com/meganode_storage/6.12/wallarm-6.12.5.x86_64-glibc.sh"
}

func InstallNode(node state.Node, apiToken, apiHost, labels string) error {
	if apiToken == "" {
		return fmt.Errorf("API token required")
	}
	_ = labels

	instanceDir := filepath.Join(BaseDir, node.Name, "wallarm")
	installerPath := filepath.Join(BaseDir, "wallarm-aio.sh")

	// 1. Prepare clean /opt/wallarm for this deployment
	os.RemoveAll(DeployTo)
	os.MkdirAll(DeployTo, 0755)

	// 2. Kill any existing process on the target port, then start per-instance NGINX
	port := "80"
	if idx := strings.LastIndex(node.Address, ":"); idx != -1 {
		port = node.Address[idx+1:]
	}
	killPort(port)
	copyNginx(DeployTo)
	startNginx(DeployTo, node, port)

	// 3. Download AIO once
	if _, err := os.Stat(installerPath); os.IsNotExist(err) {
		fmt.Printf("[%s] Downloading installer...\n", node.Name)
		cmd := exec.Command("curl", "-fsSL", "-o", installerPath, installerURL())
		if out, err := cmd.CombinedOutput(); err != nil {
			return fmt.Errorf("download: %w\n%s", err, string(out))
		}
		os.Chmod(installerPath, 0755)
	}

	// 4. Extract AIO to /opt/wallarm
	fmt.Printf("[%s] Extracting...\n", node.Name)
	cmd := exec.Command("bash", installerPath, "--noexec", "--keep", "--target", DeployTo, "--noprogress", "--accept")
	if out, err := cmd.CombinedOutput(); err != nil {
		return fmt.Errorf("extract: %w\n%s", err, string(out))
	}

	// 5. Fix: recreate env.list in background while setup.sh runs
	done := make(chan struct{})
	go func() {
		defer close(done)
		for {
			select {
			case <-done:
				return
			default:
				os.WriteFile(filepath.Join(DeployTo, "env.list"),
					[]byte("# wallarm env\n"), 0644)
				time.Sleep(500 * time.Millisecond)
			}
		}
	}()

	// 6. Run setup.sh
	fmt.Printf("[%s] Running setup...\n", node.Name)
	cmd = exec.Command("bash", filepath.Join(DeployTo, "setup.sh"),
		"--batch", "--token", apiToken, "--cloud", cloudFromHost(apiHost),
		"--custom-ngx-build",
	)
	cmd.Dir = DeployTo

	logFile, _ := os.Create(filepath.Join(DeployTo, "install.log"))
	if logFile != nil {
		cmd.Stdout = logFile
		cmd.Stderr = logFile
	}
	runErr := cmd.Run()
	close(done) // stop env.list keeper
	if logFile != nil {
		logFile.Close()
	}
	if runErr != nil {
		if data, _ := os.ReadFile(filepath.Join(DeployTo, "install.log")); len(data) > 0 {
			lines := strings.Split(string(data), "\n")
			s := len(lines) - 5
			if s < 0 {
				s = 0
			}
			return fmt.Errorf("%s", strings.Join(lines[s:], "\n"))
		}
		return fmt.Errorf("setup failed: %v", runErr)
	}

	// 6. Move /opt/wallarm → /opt/fw/{name}/wallarm
	os.MkdirAll(BaseDir+"/"+node.Name, 0755)
	os.RemoveAll(instanceDir)
	if err := os.Rename(DeployTo, instanceDir); err != nil {
		return fmt.Errorf("move to instance dir: %w", err)
	}

	fmt.Printf("[%s] Done. Installed to %s\n", node.Name, instanceDir)
	return nil
}

func copyNginx(dir string) {
	dst := filepath.Join(dir, "nginx", "sbin", "nginx")
	if _, err := os.Stat(dst); err == nil {
		return
	}
	os.MkdirAll(filepath.Dir(dst), 0755)
	if path, err := exec.LookPath("nginx"); err == nil {
		exec.Command("cp", path, dst).Run()
		return
	}
	for _, pm := range [][]string{
		{"apt-get", "install", "-y", "-qq", "nginx"},
		{"yum", "install", "-y", "-q", "nginx"},
	} {
		if _, err := exec.LookPath(pm[0]); err == nil {
			exec.Command(pm[0], pm[1:]...).Run()
			if path, err := exec.LookPath("nginx"); err == nil {
				exec.Command("cp", path, dst).Run()
				return
			}
		}
	}
}

func cloudFromHost(host string) string {
	if strings.Contains(host, "us1") {
		return "US"
	}
	return "EU"
}

func CreateNodesDir() error           { return os.MkdirAll(BaseDir, 0755) }
func GenerateSystemdTemplate() error  { return nil }
func RemoveNode(name string) error    { return nil }
func Status(name string) (string, error) { return "", nil }

func startNginx(dir string, node state.Node, port string) {
	nginxDir := filepath.Join(dir, "nginx")
	confDir := filepath.Join(nginxDir, "conf")
	os.MkdirAll(confDir, 0755)
	confPath := filepath.Join(confDir, "nginx.conf")
	os.WriteFile(confPath, []byte(fmt.Sprintf(`
worker_processes auto;
pid %s/nginx.pid;
error_log %s/error.log;
events { worker_connections 10240; }
http {
    access_log %s/access.log;
    server {
        listen %s;
        server_name _;
        location /health { return 200; }
    }
}
`, nginxDir, nginxDir, nginxDir, port)), 0644)

	bin := filepath.Join(nginxDir, "sbin", "nginx")
	cmd := exec.Command(bin, "-c", confPath, "-p", nginxDir)
	cmd.Dir = nginxDir
	if out, err := cmd.CombinedOutput(); err != nil {
		fmt.Printf("[%s] NGINX start: %v\n%s\n", node.Name, err, string(out))
	} else {
		fmt.Printf("[%s] NGINX started on port %s\n", node.Name, port)
	}
}

func killPort(port string) {
	// Find and kill any process listening on the target port
	out, _ := exec.Command("fuser", "-k", port+"/tcp").CombinedOutput()
	if len(out) > 0 {
		fmt.Printf("  Killed existing process on port %s\n", port)
	}
}