feat(auth): add user captcha generation endpoint

- Add handler for /v1/auth/captcha/generate endpoint
- Implement captcha generation logic based on configuration
- Support local image captcha generation with Redis storage
- Return Turnstile site key for Turnstile mode
- Check EnableUserLoginCaptcha configuration

internal/handler/auth/generateCaptchaHandler.go

@@ -0,0 +1,18 @@
+package auth
+
+import (
+	"github.com/gin-gonic/gin"
+	"github.com/perfect-panel/server/internal/logic/auth"
+	"github.com/perfect-panel/server/internal/svc"
+	"github.com/perfect-panel/server/pkg/result"
+)
+
+// Generate captcha
+func GenerateCaptchaHandler(svcCtx *svc.ServiceContext) func(c *gin.Context) {
+	return func(c *gin.Context) {
+
+		l := auth.NewGenerateCaptchaLogic(c.Request.Context(), svcCtx)
+		resp, err := l.GenerateCaptcha()
+		result.HttpResult(c, resp, err)
+	}
+}

internal/logic/auth/generateCaptchaLogic.go

@@ -0,0 +1,70 @@
+package auth
+
+import (
+	"context"
+
+	"github.com/perfect-panel/server/internal/svc"
+	"github.com/perfect-panel/server/internal/types"
+	"github.com/perfect-panel/server/pkg/captcha"
+	"github.com/perfect-panel/server/pkg/logger"
+	"github.com/perfect-panel/server/pkg/tool"
+	"github.com/perfect-panel/server/pkg/xerr"
+	"github.com/pkg/errors"
+)
+
+type GenerateCaptchaLogic struct {
+	logger.Logger
+	ctx    context.Context
+	svcCtx *svc.ServiceContext
+}
+
+// Generate captcha
+func NewGenerateCaptchaLogic(ctx context.Context, svcCtx *svc.ServiceContext) *GenerateCaptchaLogic {
+	return &GenerateCaptchaLogic{
+		Logger: logger.WithContext(ctx),
+		ctx:    ctx,
+		svcCtx: svcCtx,
+	}
+}
+
+func (l *GenerateCaptchaLogic) GenerateCaptcha() (resp *types.GenerateCaptchaResponse, err error) {
+	resp = &types.GenerateCaptchaResponse{}
+
+	// Get verify config from database
+	verifyCfg, err := l.svcCtx.SystemModel.GetVerifyConfig(l.ctx)
+	if err != nil {
+		l.Logger.Error("[GenerateCaptchaLogic] GetVerifyConfig error: ", logger.Field("error", err.Error()))
+		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DatabaseQueryError), "GetVerifyConfig error: %v", err.Error())
+	}
+
+	var config struct {
+		CaptchaType      string `json:"captcha_type"`
+		TurnstileSiteKey string `json:"turnstile_site_key"`
+		TurnstileSecret  string `json:"turnstile_secret"`
+	}
+	tool.SystemConfigSliceReflectToStruct(verifyCfg, &config)
+
+	resp.Type = config.CaptchaType
+
+	// If captcha type is local, generate captcha image
+	if config.CaptchaType == "local" {
+		captchaService := captcha.NewService(captcha.Config{
+			Type:        captcha.CaptchaTypeLocal,
+			RedisClient: l.svcCtx.Redis,
+		})
+
+		id, image, err := captchaService.Generate(l.ctx)
+		if err != nil {
+			l.Logger.Error("[GenerateCaptchaLogic] Generate captcha error: ", logger.Field("error", err.Error()))
+			return nil, errors.Wrapf(xerr.NewErrCode(xerr.ERROR), "Generate captcha error: %v", err.Error())
+		}
+
+		resp.Id = id
+		resp.Image = image
+	} else if config.CaptchaType == "turnstile" {
+		// For Turnstile, just return the site key
+		resp.Id = config.TurnstileSiteKey
+	}
+
+	return resp, nil
+}