publish: 1.0.0 snapshot (bad2ec1)

channel: master
version: 1.0.0
source-ref: master
published-at-utc: 2026-03-13T15:19:28Z

backend/internal/launchcode/service.go

@@ -0,0 +1,208 @@
+package launchcode
+
+import (
+	"crypto/rand"
+	"fmt"
+	"regexp"
+	"strings"
+	"sync"
+)
+
+const charset = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+const codeLen = 6
+const maxRetries = 10
+const customCodeMinLen = 4
+const customCodeMaxLen = 32
+
+var customCodePattern = regexp.MustCompile(`^[A-Z0-9_-]+$`)
+
+// LaunchCodeService 负责 Launch Code 的生成、缓存与管理
+type LaunchCodeService struct {
+	dao           LaunchCodeDAO
+	codeToProfile map[string]string
+	profileToCode map[string]string
+	mu            sync.RWMutex
+}
+
+// NewLaunchCodeService 创建 LaunchCodeService
+func NewLaunchCodeService(dao LaunchCodeDAO) *LaunchCodeService {
+	return &LaunchCodeService{
+		dao:           dao,
+		codeToProfile: make(map[string]string),
+		profileToCode: make(map[string]string),
+	}
+}
+
+// EnsureCode 为 profile 生成并持久化 code（幂等：已有则直接返回）
+func (s *LaunchCodeService) EnsureCode(profileId string) (string, error) {
+	s.mu.RLock()
+	if code, ok := s.profileToCode[profileId]; ok {
+		s.mu.RUnlock()
+		return code, nil
+	}
+	s.mu.RUnlock()
+
+	code, err := s.generateUniqueCode()
+	if err != nil {
+		return "", err
+	}
+
+	if err := s.dao.Upsert(profileId, code); err != nil {
+		return "", err
+	}
+
+	s.mu.Lock()
+	s.profileToCode[profileId] = code
+	s.codeToProfile[code] = profileId
+	s.mu.Unlock()
+
+	return code, nil
+}
+
+// SetCode 为指定 profile 设置自定义 launch code。
+// code 会自动 trim 并转为大写；格式限制为 4-32 位，字符集 [A-Z0-9_-]。
+func (s *LaunchCodeService) SetCode(profileId, code string) (string, error) {
+	code = normalizeCode(code)
+	if err := validateCustomCode(code); err != nil {
+		return "", err
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if old, ok := s.profileToCode[profileId]; ok && old == code {
+		return code, nil
+	}
+
+	if ownerProfile, exists := s.codeToProfile[code]; exists && ownerProfile != profileId {
+		return "", fmt.Errorf("launch code already exists")
+	}
+
+	if err := s.dao.Upsert(profileId, code); err != nil {
+		return "", err
+	}
+
+	if old, ok := s.profileToCode[profileId]; ok {
+		delete(s.codeToProfile, old)
+	}
+	s.profileToCode[profileId] = code
+	s.codeToProfile[code] = profileId
+	return code, nil
+}
+
+// RegenerateCode 重新生成 code（废弃旧 code）
+func (s *LaunchCodeService) RegenerateCode(profileId string) (string, error) {
+	s.mu.Lock()
+	if oldCode, ok := s.profileToCode[profileId]; ok {
+		delete(s.codeToProfile, oldCode)
+		delete(s.profileToCode, profileId)
+	}
+	s.mu.Unlock()
+
+	code, err := s.generateUniqueCode()
+	if err != nil {
+		return "", err
+	}
+
+	if err := s.dao.Upsert(profileId, code); err != nil {
+		return "", err
+	}
+
+	s.mu.Lock()
+	s.profileToCode[profileId] = code
+	s.codeToProfile[code] = profileId
+	s.mu.Unlock()
+
+	return code, nil
+}
+
+// Resolve 根据 code 查找 profileId（仅查内存缓存）
+func (s *LaunchCodeService) Resolve(code string) (string, error) {
+	code = normalizeCode(code)
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	profileId, ok := s.codeToProfile[code]
+	if !ok {
+		return "", fmt.Errorf("launch code not found: %s", code)
+	}
+	return profileId, nil
+}
+
+// Remove 删除 profile 对应的 code（同时清理内存缓存和数据库）
+func (s *LaunchCodeService) Remove(profileId string) error {
+	s.mu.Lock()
+	if code, ok := s.profileToCode[profileId]; ok {
+		delete(s.codeToProfile, code)
+		delete(s.profileToCode, profileId)
+	}
+	s.mu.Unlock()
+
+	return s.dao.Delete(profileId)
+}
+
+// LoadAll 启动时从数据库加载所有映射到内存
+func (s *LaunchCodeService) LoadAll() error {
+	profileToCode, err := s.dao.LoadAll()
+	if err != nil {
+		return err
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	s.profileToCode = make(map[string]string, len(profileToCode))
+	s.codeToProfile = make(map[string]string, len(profileToCode))
+
+	for profileId, code := range profileToCode {
+		s.profileToCode[profileId] = code
+		s.codeToProfile[code] = profileId
+	}
+	return nil
+}
+
+// generateUniqueCode 生成一个在内存缓存中唯一的 code
+func (s *LaunchCodeService) generateUniqueCode() (string, error) {
+	for i := 0; i < maxRetries; i++ {
+		code, err := randomCode()
+		if err != nil {
+			return "", fmt.Errorf("生成 launch code 失败: %w", err)
+		}
+
+		s.mu.RLock()
+		_, exists := s.codeToProfile[code]
+		s.mu.RUnlock()
+
+		if !exists {
+			return code, nil
+		}
+	}
+	return "", fmt.Errorf("无法在 %d 次重试内生成唯一 launch code", maxRetries)
+}
+
+// randomCode 使用 crypto/rand 生成一个随机 6 位字符串
+func randomCode() (string, error) {
+	buf := make([]byte, codeLen)
+	if _, err := rand.Read(buf); err != nil {
+		return "", err
+	}
+	result := make([]byte, codeLen)
+	for i, b := range buf {
+		result[i] = charset[int(b)%len(charset)]
+	}
+	return string(result), nil
+}
+
+func normalizeCode(code string) string {
+	return strings.ToUpper(strings.TrimSpace(code))
+}
+
+func validateCustomCode(code string) error {
+	if len(code) < customCodeMinLen || len(code) > customCodeMaxLen {
+		return fmt.Errorf("launch code must be %d-%d characters", customCodeMinLen, customCodeMaxLen)
+	}
+	if !customCodePattern.MatchString(code) {
+		return fmt.Errorf("launch code format invalid: only A-Z, 0-9, _ and - are allowed")
+	}
+	return nil
+}