// Package naviscore is a gomobile-friendly wrapper that runs Xray or Hysteria2
// in-process (macOS Manager semantics: local SOCKS/HTTP listeners).
//
// Build:
//
//	gomobile bind -target=ios,iossimulator -o ios/Vendor/NavisCore.xcframework ./mobile/naviscore
package naviscore

import (
	"encoding/json"
	"errors"
	"fmt"
	"net"
	"os"
	"path/filepath"
	"sync"
	"time"

	libxrayxray "github.com/xtls/libxray/xray"
)

var (
	mu      sync.Mutex
	mode    string // "xray" | "hy2" | ""
	hy2Stop func() error
	workDir string
)

// SetWorkDir sets a writable directory for runtime config files (extension container).
func SetWorkDir(dir string) {
	mu.Lock()
	defer mu.Unlock()
	workDir = dir
}

// StartXrayJSON runs Xray from a full config JSON string (SOCKS/HTTP inbounds included).
func StartXrayJSON(configJSON string) error {
	mu.Lock()
	defer mu.Unlock()
	if mode != "" {
		return errors.New("core already running")
	}
	if err := libxrayxray.RunXrayFromJSON(configJSON); err != nil {
		return err
	}
	mode = "xray"
	return nil
}

// StartXrayFile runs Xray from a config.json path.
func StartXrayFile(configPath string) error {
	mu.Lock()
	defer mu.Unlock()
	if mode != "" {
		return errors.New("core already running")
	}
	if err := libxrayxray.RunXray(configPath); err != nil {
		return err
	}
	mode = "xray"
	return nil
}

// StartHy2YAML writes YAML to workDir and starts the Hysteria2 client library.
// If the hysteria embed is unavailable in this build, returns a clear error.
func StartHy2YAML(configYAML string) error {
	mu.Lock()
	defer mu.Unlock()
	if mode != "" {
		return errors.New("core already running")
	}
	dir := workDir
	if dir == "" {
		dir = os.TempDir()
	}
	if err := os.MkdirAll(dir, 0o700); err != nil {
		return err
	}
	path := filepath.Join(dir, "hy2.yaml")
	if err := os.WriteFile(path, []byte(configYAML), 0o600); err != nil {
		return err
	}
	stop, err := startHysteria2(path)
	if err != nil {
		return err
	}
	hy2Stop = stop
	mode = "hy2"
	return nil
}

// Stop stops whichever core is running.
func Stop() error {
	mu.Lock()
	defer mu.Unlock()
	var err error
	switch mode {
	case "xray":
		err = libxrayxray.StopXray()
	case "hy2":
		if hy2Stop != nil {
			err = hy2Stop()
			hy2Stop = nil
		}
	}
	mode = ""
	return err
}

// IsRunning reports whether a core is active.
func IsRunning() bool {
	mu.Lock()
	defer mu.Unlock()
	switch mode {
	case "xray":
		return libxrayxray.GetXrayState()
	case "hy2":
		return hy2Stop != nil
	default:
		return false
	}
}

// WaitPort waits until TCP 127.0.0.1:port accepts connections.
func WaitPort(port int, timeoutMs int) error {
	if port <= 0 {
		return fmt.Errorf("bad port")
	}
	deadline := time.Now().Add(time.Duration(timeoutMs) * time.Millisecond)
	addr := net.JoinHostPort("127.0.0.1", fmt.Sprintf("%d", port))
	for time.Now().Before(deadline) {
		c, err := net.DialTimeout("tcp", addr, 200*time.Millisecond)
		if err == nil {
			_ = c.Close()
			return nil
		}
		time.Sleep(100 * time.Millisecond)
	}
	return fmt.Errorf("локальный прокси :%d не поднялся", port)
}

// Version returns a short build label.
func Version() string {
	return "naviscore/xray+hy2"
}

// PingJSON is a tiny helper so Swift can verify the framework linked.
func PingJSON() string {
	b, _ := json.Marshal(map[string]any{"ok": true, "version": Version()})
	return string(b)
}