Fix filesize multiplier default in web generation flow

internal/extractor/magic.go

@@ -18,6 +18,9 @@ func GetFileRange(size int64, multiplier int) string {
 	if size <= 0 {
 		return ""
 	}
+	if multiplier <= 0 {
+		multiplier = 3
+	}
 
 	maxSize := size * int64(multiplier)
 	if maxSize < 1024 {

internal/rules/generator.go

@@ -270,6 +270,10 @@ func getMagicCondition(magic string) string {
 }
 
 func getFilesizeCondition(size int64, multiplier int) string {
+	if multiplier <= 0 {
+		multiplier = 3
+	}
+
 	maxSize := size * int64(multiplier)
 	if maxSize < 1024 {
 		maxSize = 1024

internal/rules/generator_test.go

@@ -37,3 +37,11 @@ func TestGenerateSimpleRuleEscapesMetaValues(t *testing.T) {
 		t.Fatalf("expected escaped reference in generated rule, got:\n%s", rule)
 	}
 }
+
+func TestGetFilesizeCondition_DefaultsMultiplierWhenUnset(t *testing.T) {
+	got := getFilesizeCondition(49*1024, 0)
+
+	if got != "filesize < 200KB" {
+		t.Fatalf("unexpected filesize condition: got %q want %q", got, "filesize < 200KB")
+	}
+}

internal/web/handlers.go

@@ -225,19 +225,20 @@ func (s *Server) handleUpload(w http.ResponseWriter, r *http.Request) {
 
 // GenerateRequest contains parameters for rule generation.
 type GenerateRequest struct {
-	JobID           string  `json:"job_id"`
-	Author          string  `json:"author"`
-	Reference       string  `json:"reference"`
-	ShowScores      bool    `json:"show_scores"`
-	ExcludeOpcodes  bool    `json:"exclude_opcodes"`
-	NoSuper         bool    `json:"no_super"`
-	ExcludeGoodware bool    `json:"exclude_goodware"`
-	NoMagic         bool    `json:"no_magic"`
-	NoFilesize      bool    `json:"no_filesize"`
-	UseLLM          bool    `json:"use_llm"`
-	MinScore        float64 `json:"min_score"`
-	MaxStrings      int     `json:"max_strings"`
-	Debug           bool    `json:"debug"`
+	JobID            string  `json:"job_id"`
+	Author           string  `json:"author"`
+	Reference        string  `json:"reference"`
+	ShowScores       bool    `json:"show_scores"`
+	ExcludeOpcodes   bool    `json:"exclude_opcodes"`
+	NoSuper          bool    `json:"no_super"`
+	ExcludeGoodware  bool    `json:"exclude_goodware"`
+	NoMagic          bool    `json:"no_magic"`
+	NoFilesize       bool    `json:"no_filesize"`
+	FilesizeMultiply int     `json:"filesize_multiplier"`
+	UseLLM           bool    `json:"use_llm"`
+	MinScore         float64 `json:"min_score"`
+	MaxStrings       int     `json:"max_strings"`
+	Debug            bool    `json:"debug"`
 }
 
 func (s *Server) handleGenerate(w http.ResponseWriter, r *http.Request) {
@@ -290,6 +291,7 @@ func (s *Server) handleGenerate(w http.ResponseWriter, r *http.Request) {
 			ExcludeGoodware:  req.ExcludeGoodware,
 			NoMagic:          req.NoMagic,
 			NoFilesize:       req.NoFilesize,
+			FilesizeMultiply: req.FilesizeMultiply,
 			UseLLM:           req.UseLLM,
 			MinScore:         req.MinScore,
 			MaxStrings:       req.MaxStrings,
@@ -305,6 +307,9 @@ func (s *Server) handleGenerate(w http.ResponseWriter, r *http.Request) {
 		if opts.Author == "" {
 			opts.Author = "yarGen"
 		}
+		if opts.FilesizeMultiply <= 0 {
+			opts.FilesizeMultiply = 3
+		}
 
 		result, err := s.yargen.Generate(ctx, opts)
 

internal/web/static/js/app.js

@@ -116,6 +116,7 @@ function generateRules() {
         exclude_goodware: document.getElementById('opt-exclude-good').checked,
         no_magic: document.getElementById('opt-no-magic').checked,
         no_filesize: document.getElementById('opt-no-filesize').checked,
+        filesize_multiplier: parseInt(document.getElementById('opt-fs-mult').value) || 3,
         use_llm: document.getElementById('opt-llm').checked,
         min_score: parseFloat(document.getElementById('opt-min-score').value) || 0,
         max_strings: parseInt(document.getElementById('opt-max-strings').value) || 20,