feat: enhance learn-number with dynamic SVG icons, multi-page support, and modular UI

pkg/learnnumber/data/icons.go

@@ -1,41 +1,77 @@
 package data
 
+import (
+	"encoding/xml"
+	"fmt"
+	"os"
+	"strings"
+)
+
 type Icon struct {
 	Name  string
 	Paths []string
 }
 
-// 升级版：更卡通、更饱满的简笔画
-var CountingIcons = []Icon{
-	{Name: "Bear", Paths: []string{
-		"M 512 800 C 300 800 200 700 200 500 C 200 300 350 200 512 200 C 674 200 824 300 824 500 C 824 700 724 800 512 800 Z", // Body
-		"M 300 300 m -50 0 a 50 50 0 1 0 100 0 a 50 50 0 1 0 -100 0", // Ear L
-		"M 724 300 m -50 0 a 50 50 0 1 0 100 0 a 50 50 0 1 0 -100 0", // Ear R
-		"M 400 450 m -20 0 a 20 20 0 1 0 40 0 a 20 20 0 1 0 -40 0",   // Eye L
-		"M 624 450 m -20 0 a 20 20 0 1 0 40 0 a 20 20 0 1 0 -40 0",   // Eye R
-		"M 512 550 Q 512 650 400 650 M 512 550 Q 512 650 624 650",    // Mouth
-	}},
-	{Name: "Cat", Paths: []string{
-		"M 200 800 L 300 400 L 400 200 L 512 350 L 624 200 L 724 400 L 824 800 Z", // Head
-		"M 400 550 m -15 0 a 15 15 0 1 0 30 0 a 15 15 0 1 0 -30 0", // Eye L
-		"M 624 550 m -15 0 a 15 15 0 1 0 30 0 a 15 15 0 1 0 -30 0", // Eye R
-		"M 512 650 L 450 700 M 512 650 L 574 700", // Nose
-	}},
-	{Name: "Car", Paths: []string{
-		"M 100 700 L 100 500 Q 100 400 300 400 L 700 400 Q 900 400 900 500 L 900 700 Z", // Body
-		"M 250 700 m -60 0 a 60 60 0 1 0 120 0 a 60 60 0 1 0 -120 0", // Wheel L
-		"M 750 700 m -60 0 a 60 60 0 1 0 120 0 a 60 60 0 1 0 -120 0", // Wheel R
-		"M 300 400 L 400 250 L 624 250 L 724 400", // Roof
-	}},
-	{Name: "Bird", Paths: []string{
-		"M 512 512 m -300 0 a 300 300 0 1 0 600 0 a 300 300 0 1 0 -600 0", // Body
-		"M 812 512 L 950 450 L 812 400 Z", // Beak
-		"M 400 400 m -20 0 a 20 20 0 1 0 40 0 a 20 20 0 1 0 -40 0", // Eye
-		"M 212 512 Q 100 400 212 300", // Wing
-	}},
-	{Name: "Rocket", Paths: []string{
-		"M 512 100 Q 700 400 700 800 L 324 800 Q 324 400 512 100 Z", // Body
-		"M 512 400 m -50 0 a 50 50 0 1 0 100 0 a 50 50 0 1 0 -100 0", // Window
-		"M 324 800 L 200 950 L 324 900 M 700 800 L 824 950 L 700 900", // Fins
-	}},
+var IconCategories = map[string][]Icon{
+	"shapes": {
+		{Name: "Circle", Paths: []string{"M 512 112 C 291 112 112 291 112 512 C 112 733 291 912 512 912 C 733 912 912 733 912 512 C 912 291 733 112 512 112 Z"}},
+		{Name: "Square", Paths: []string{"M 150 150 L 874 150 L 874 874 L 150 874 Z"}},
+		{Name: "Rectangle", Paths: []string{"M 100 300 L 924 300 L 924 724 L 100 724 Z"}},
+		{Name: "Triangle", Paths: []string{"M 512 150 L 900 850 L 124 850 Z"}},
+		{Name: "Star", Paths: []string{"M 512 100 L 612 400 L 924 400 L 674 600 L 774 900 L 512 700 L 250 900 L 350 600 L 100 400 L 412 400 Z"}},
+		{Name: "Heart", Paths: []string{"M 512 900 C 200 700 100 500 100 300 C 100 100 400 100 512 250 C 624 100 924 100 924 300 C 924 500 824 700 512 900 Z"}},
+		{Name: "Diamond", Paths: []string{"M 512 100 L 900 512 L 512 924 L 124 512 Z"}},
+		{Name: "Oval", Paths: []string{"M 512 350 C 200 350 100 420 100 512 C 100 604 200 674 512 674 C 824 674 924 604 924 512 C 924 420 824 350 512 350 Z"}},
+		{Name: "Trapezoid", Paths: []string{"M 300 200 L 724 200 L 924 800 L 100 800 Z"}},
+		{Name: "Hexagon", Paths: []string{"M 512 100 L 858 300 L 858 724 L 512 924 L 166 724 L 166 300 Z"}},
+	},
+	"fruits": {}, 
+}
+
+type SVG struct {
+	Groups []G `xml:"g"`
+}
+
+type G struct {
+	ID     string `xml:"id,attr"`
+	Groups []G    `xml:"g"`
+	Paths  []Path `xml:"path"`
+}
+
+type Path struct {
+	D string `xml:"d,attr"`
+}
+
+func LoadIcons(filePath string) error {
+	data, err := os.ReadFile(filePath)
+	if err != nil { return err }
+	var svg SVG
+	if err := xml.Unmarshal(data, &svg); err != nil { return err }
+	var objectsG *G
+	for i := range svg.Groups {
+		if svg.Groups[i].ID == "objects" { objectsG = &svg.Groups[i]; break }
+	}
+	if objectsG == nil { return nil }
+	var fruitIcons []Icon
+	for i, g := range objectsG.Groups {
+		paths := collectPaths(g)
+		if len(paths) > 0 {
+			fruitIcons = append(fruitIcons, Icon{
+				Name:  fmt.Sprintf("Item %d", i+1),
+				Paths: paths,
+			})
+		}
+	}
+	IconCategories["fruits"] = fruitIcons
+	return nil
+}
+
+func collectPaths(g G) []string {
+	var paths []string
+	for _, p := range g.Paths {
+		d := strings.TrimSpace(p.D)
+		if d != "" { paths = append(paths, d) }
+	}
+	for _, subG := range g.Groups { paths = append(paths, collectPaths(subG)...) }
+	return paths
 }

pkg/learnnumber/logic/counting.go

@@ -16,10 +16,21 @@ import (
 type CountingRequest struct {
 	TotalCount int    `json:"total_count"`
 	IconTypes  int    `json:"icon_types"`
+	PageCount  int    `json:"page_count"`
+	Category   string `json:"category"`
 	PaperSize  string `json:"paper_size"`
 }
 
-var reSVG = regexp.MustCompile(`([MLQCZmlqcz])|(-?\d+\.?\d*)`)
+type PlacedIcon struct {
+	X, Y, Radius float64
+}
+
+type PathResult struct {
+	Points []gopdf.Point
+	Closed bool
+}
+
+var reSVGToken = regexp.MustCompile(`[a-zA-Z]|-?\d+\.?\d*`)
 
 func GenerateCountingPDF(req CountingRequest) ([]byte, error) {
 	rand.Seed(time.Now().UnixNano())
@@ -27,142 +38,182 @@ func GenerateCountingPDF(req CountingRequest) ([]byte, error) {
 	rect := gopdf.Rect{W: 595.28, H: 841.89}
 	if req.PaperSize == "Letter" { rect = gopdf.Rect{W: 612, H: 792} }
 	pdf.Start(gopdf.Config{PageSize: rect})
-	pdf.AddPage()
 
-	drawProblem(pdf, req, 0, rect.W, rect.H/2)
-	drawProblem(pdf, req, rect.H/2, rect.W, rect.H/2)
+	// 硬性限制：页数 1-10 页，防止资源耗尽
+	if req.PageCount < 1 { req.PageCount = 1 }
+	if req.PageCount > 10 { req.PageCount = 10 }
+
+	for i := 0; i < req.PageCount; i++ {
+		pdf.AddPage()
+		drawProblemV4(pdf, req, 0, rect.W, rect.H/2)
+		drawProblemV4(pdf, req, rect.H/2, rect.W, rect.H/2)
+	}
 
 	var buf bytes.Buffer
 	_, err := pdf.WriteTo(&buf)
 	return buf.Bytes(), err
 }
 
-func drawProblem(pdf *gopdf.GoPdf, req CountingRequest, startY, pW, pH float64) {
+func drawProblemV4(pdf *gopdf.GoPdf, req CountingRequest, startY, pW, pH float64) {
 	margin := 40.0
-	boxW := (pW - 2*margin) * 0.7
-	boxH := pH - 60.0
-	x, y := margin, startY + 30.0
+	boxW, boxH := (pW-2*margin)*0.7, pH-60.0
+	xBase, yBase := margin, startY + 30.0
 
-	// 1. 绘制方框
-	pdf.SetStrokeColor(0, 0, 0); pdf.SetLineWidth(2.0)
-	pdf.RectFromUpperLeft(x, y, boxW, boxH)
+	pdf.SetStrokeColor(0, 0, 0); pdf.SetLineWidth(2.5)
+	pdf.RectFromUpperLeft(xBase, yBase, boxW, boxH)
 
-	// 2. 分配图标数量
-	numTypes := req.IconTypes; if numTypes < 1 { numTypes = 1 }
-	if numTypes > len(data.CountingIcons) { numTypes = len(data.CountingIcons) }
+	catIcons := data.IconCategories[req.Category]
+	if len(catIcons) == 0 { catIcons = data.IconCategories["shapes"] }
 	
-	total := req.TotalCount; if total < numTypes { total = numTypes }
-	if total > 30 { total = 30 }
-
-	// 随机选出图标种类
-	allIcons := rand.Perm(len(data.CountingIcons))
-	selectedIcons := []data.Icon{}
-	counts := []int{}
+	numTypes := req.IconTypes
+	if numTypes < 1 { numTypes = 1 }; if numTypes > 6 { numTypes = 6 }
+	if numTypes > len(catIcons) { numTypes = len(catIcons) }
 	
-	// 先每种分配1个
-	rem := total - numTypes
+	total := req.TotalCount
+	if total < numTypes { total = numTypes }; if total > 30 { total = 30 }
+
+	allIconsPerm := rand.Perm(len(catIcons))
+	var selectedIcons []data.Icon
+	counts := make([]int, numTypes)
+	
+	// 随机分配逻辑
 	for i := 0; i < numTypes; i++ {
-		selectedIcons = append(selectedIcons, data.CountingIcons[allIcons[i]])
-		counts = append(counts, 1)
+		selectedIcons = append(selectedIcons, catIcons[allIconsPerm[i]])
+		counts[i] = 1
 	}
-	// 随机分配剩下的
-	for i := 0; i < rem; i++ {
+	remaining := total - numTypes
+	for i := 0; i < remaining; i++ {
 		counts[rand.Intn(numTypes)]++
 	}
 
-	// 3. 布局计划 (使用网格，增加 Padding 避开边框)
-	rows, cols := 5, 6
-	cellW, cellH := boxW/float64(cols), boxH/float64(rows)
-	indices := rand.Perm(rows * cols)
-	
-	// 严格图标大小：单元格的 70%，确保不溢出单元格边界
-	iconSize := math.Min(cellW, cellH) * 0.7
-	paddingX, paddingY := (cellW - iconSize)/2, (cellH - iconSize)/2
+	avgRadius := math.Sqrt((boxW * boxH * 0.22) / (float64(total) * math.Pi))
+	if avgRadius > 35.0 { avgRadius = 35.0 }
 
-	iconTypeIdx := 0
-	countInCurrentType := 0
-	
+	var placed []PlacedIcon
+	iconTypeIdx, currentInType := 0, 0
 	for i := 0; i < total; i++ {
-		cellIdx := indices[i]
-		rIdx, cIdx := cellIdx/cols, cellIdx%cols
-		
-		// 基础位置
-		baseX := x + float64(cIdx)*cellW + paddingX
-		baseY := y + float64(rIdx)*cellH + paddingY
-		
-		// 渲染图标
-		drawIcon(pdf, selectedIcons[iconTypeIdx], baseX + iconSize/2, baseY + iconSize/2, iconSize)
-		
-		countInCurrentType++
-		if countInCurrentType >= counts[iconTypeIdx] {
-			iconTypeIdx++
-			countInCurrentType = 0
-		}
-	}
-
-	// 4. 绘制右侧对照表
-	legendX := x + boxW + 20.0
-	legendStepY := boxH / float64(numTypes + 1)
-	for i := 0; i < numTypes; i++ {
-		lY := y + float64(i+1)*legendStepY
-		drawIcon(pdf, selectedIcons[i], legendX + 20, lY, 30)
-		pdf.SetStrokeColor(150, 150, 150); pdf.SetLineWidth(0.8)
-		pdf.RectFromUpperLeft(legendX + 50, lY - 15, 30, 30)
-	}
-}
-
-func drawIcon(pdf *gopdf.GoPdf, icon data.Icon, cX, cY, size float64) {
-	scale := size / 1024.0
-	pdf.SetStrokeColor(0, 0, 0); pdf.SetLineWidth(1.5) // 加粗线条
-	
-	ox, oy := cX - size/2, cY - size/2
-	for _, pStr := range icon.Paths {
-		pts := parseSmoothPath(pStr, scale, ox, oy)
-		if len(pts) > 1 {
-			// 如果是闭合路径
-			if strings.Contains(strings.ToUpper(pStr), "Z") {
-				pdf.Polygon(pts, "D")
-			} else {
-				for i := 0; i < len(pts)-1; i++ {
-					pdf.Line(pts[i].X, pts[i].Y, pts[i+1].X, pts[i+1].Y)
+		scaleVar := 0.9 + rand.Float64()*0.2; r := avgRadius * scaleVar
+		for retry := 0; retry < 200; retry++ {
+			randX := xBase + r + 5 + rand.Float64()*(boxW-2*r-10)
+			randY := yBase + r + 5 + rand.Float64()*(boxH-2*r-10)
+			collision := false
+			for _, p := range placed {
+				if math.Sqrt(math.Pow(randX-p.X, 2)+math.Pow(randY-p.Y, 2)) < (r + p.Radius + 10.0) {
+					collision = true; break
 				}
 			}
+			if !collision {
+				drawSimpleIcon(pdf, selectedIcons[iconTypeIdx], randX, randY, r*2)
+				placed = append(placed, PlacedIcon{X: randX, Y: randY, Radius: r}); break
+			}
+		}
+		currentInType++; if currentInType >= counts[iconTypeIdx] { iconTypeIdx++; currentInType = 0 }
+	}
+
+	legendX, legendStepY := xBase+boxW+20.0, boxH/float64(numTypes+1)
+	for i := 0; i < numTypes; i++ {
+		lY := yBase + float64(i+1)*legendStepY
+		drawSimpleIcon(pdf, selectedIcons[i], legendX+25, lY, 35)
+		pdf.SetStrokeColor(150, 150, 150); pdf.SetLineWidth(1.0); pdf.RectFromUpperLeft(legendX+60, lY-15, 35, 35)
+	}
+}
+
+func drawSimpleIcon(pdf *gopdf.GoPdf, icon data.Icon, cX, cY, size float64) {
+	rawResults := parseMultiPath(icon, 1.0, 0, 0)
+	if len(rawResults) == 0 { return }
+	var minX, minY, maxX, maxY float64 = 1e9, 1e9, -1e9, -1e9
+	for _, res := range rawResults {
+		for _, p := range res.Points {
+			if p.X < minX { minX = p.X }; if p.X > maxX { maxX = p.X }
+			if p.Y < minY { minY = p.Y }; if p.Y > maxY { maxY = p.Y }
+		}
+	}
+	curW, curH := maxX-minX, maxY-minY
+	if curW <= 0 { curW = 1 }; if curH <= 0 { curH = 1 }
+	scale := size / math.Max(curW, curH)
+	ox, oy := cX-(curW*scale)/2-minX*scale, cY-(curH*scale)/2-minY*scale
+
+	pdf.SetStrokeColor(0, 0, 0)
+	if strings.Contains(strings.ToLower(icon.Name), "item") || len(icon.Paths) > 1 {
+		pdf.SetLineWidth(size / 60.0) // 复杂素材用细线 (30% less than 45 is approx 60)
+	} else {
+		pdf.SetLineWidth(size / 22.0) // 基础图形用粗线
+	}
+	for _, res := range rawResults {
+		scaledPts := make([]gopdf.Point, len(res.Points))
+		for i, p := range res.Points { scaledPts[i] = gopdf.Point{X: ox + p.X*scale, Y: oy + p.Y*scale} }
+		if len(scaledPts) > 1 {
+			if res.Closed { pdf.Polygon(scaledPts, "D") } else {
+				for j := 0; j < len(scaledPts)-1; j++ { pdf.Line(scaledPts[j].X, scaledPts[j].Y, scaledPts[j+1].X, scaledPts[j+1].Y) }
+			}
 		}
 	}
 }
 
-// 支持贝塞尔曲线采样，确保图标圆润
-func parseSmoothPath(path string, scale, ox, oy float64) []gopdf.Point {
-	var pts []gopdf.Point
-	matches := reSVG.FindAllStringSubmatch(path, -1)
-	var lx, ly float64
-	for i := 0; i < len(matches); {
-		cmd := matches[i][0]
-		if cmd == "M" || cmd == "L" {
-			x, _ := strconv.ParseFloat(matches[i+1][0], 64); y, _ := strconv.ParseFloat(matches[i+2][0], 64)
-			lx, ly = x, y
-			pts = append(pts, gopdf.Point{X: ox + x*scale, Y: oy + y*scale})
-			i += 3
-		} else if cmd == "C" {
-			x1, _ := strconv.ParseFloat(matches[i+1][0], 64); y1, _ := strconv.ParseFloat(matches[i+2][0], 64)
-			x2, _ := strconv.ParseFloat(matches[i+3][0], 64); y2, _ := strconv.ParseFloat(matches[i+4][0], 64)
-			x, _ := strconv.ParseFloat(matches[i+5][0], 64); y, _ := strconv.ParseFloat(matches[i+6][0], 64)
-			for t := 0.25; t <= 1.0; t += 0.25 {
-				tx := math.Pow(1-t, 3)*lx + 3*math.Pow(1-t, 2)*t*x1 + 3*(1-t)*math.Pow(t, 2)*x2 + math.Pow(t, 3)*x
-				ty := math.Pow(1-t, 3)*ly + 3*math.Pow(1-t, 2)*t*y1 + 3*(1-t)*math.Pow(t, 2)*y2 + math.Pow(t, 3)*y
-				pts = append(pts, gopdf.Point{X: ox + tx*scale, Y: oy + ty*scale})
+func parseMultiPath(icon data.Icon, scale, ox, oy float64) []PathResult {
+	var results []PathResult
+	for _, path := range icon.Paths {
+		tokens := reSVGToken.FindAllString(path, -1)
+		var lx, ly, startX, startY float64
+		var pts []gopdf.Point
+		var currentCmd string
+		var isRel bool
+		for i := 0; i < len(tokens); {
+			token := tokens[i]
+			if (token[0] >= 'a' && token[0] <= 'z') || (token[0] >= 'A' && token[0] <= 'Z') {
+				cmd := strings.ToUpper(token)
+				if cmd == "M" {
+					if len(pts) > 0 { results = append(results, PathResult{Points: pts, Closed: false}); pts = nil }
+				} else if cmd == "Z" {
+					if len(pts) > 0 { results = append(results, PathResult{Points: pts, Closed: true}); pts = nil }
+					lx, ly = startX, startY; i++; continue
+				}
+				currentCmd = cmd; isRel = (token[0] >= 'a' && token[0] <= 'z'); i++
+				continue
 			}
-			lx, ly = x, y; i += 7
-		} else if cmd == "Q" {
-			x1, _ := strconv.ParseFloat(matches[i+1][0], 64); y1, _ := strconv.ParseFloat(matches[i+2][0], 64)
-			x, _ := strconv.ParseFloat(matches[i+3][0], 64); y, _ := strconv.ParseFloat(matches[i+4][0], 64)
-			for t := 0.25; t <= 1.0; t += 0.25 {
-				tx := math.Pow(1-t, 2)*lx + 2*(1-t)*t*x1 + math.Pow(t, 2)*x
-				ty := math.Pow(1-t, 2)*ly + 2*(1-t)*t*y1 + math.Pow(t, 2)*y
-				pts = append(pts, gopdf.Point{X: ox + tx*scale, Y: oy + ty*scale})
+			switch currentCmd {
+			case "M", "L":
+				if i+1 >= len(tokens) { i = len(tokens); break }
+				x, _ := strconv.ParseFloat(tokens[i], 64); y, _ := strconv.ParseFloat(tokens[i+1], 64)
+				if isRel { x += lx; y += ly }
+				if currentCmd == "M" { startX, startY = x, y }
+				lx, ly = x, y
+				pts = append(pts, gopdf.Point{X: ox + x*scale, Y: oy + y*scale}); i += 2
+				if currentCmd == "M" { currentCmd = "L" }
+			case "H":
+				x, _ := strconv.ParseFloat(tokens[i], 64); if isRel { x += lx }; lx = x
+				pts = append(pts, gopdf.Point{X: ox + x*scale, Y: oy + ly*scale}); i++
+			case "V":
+				y, _ := strconv.ParseFloat(tokens[i], 64); if isRel { y += ly }; ly = y
+				pts = append(pts, gopdf.Point{X: ox + lx*scale, Y: oy + y*scale}); i++
+			case "C":
+				if i+5 >= len(tokens) { i = len(tokens); break }
+				x1, _ := strconv.ParseFloat(tokens[i], 64);   y1, _ := strconv.ParseFloat(tokens[i+1], 64)
+				x2, _ := strconv.ParseFloat(tokens[i+2], 64); y2, _ := strconv.ParseFloat(tokens[i+3], 64)
+				x,  _ := strconv.ParseFloat(tokens[i+4], 64); y,  _ := strconv.ParseFloat(tokens[i+5], 64)
+				if isRel { x1 += lx; y1 += ly; x2 += lx; y2 += ly; x += lx; y += ly }
+				for t := 0.2; t <= 1.0; t += 0.2 {
+					tx := math.Pow(1-t, 3)*lx + 3*math.Pow(1-t, 2)*t*x1 + 3*(1-t)*math.Pow(t, 2)*x2 + math.Pow(t, 3)*x
+					ty := math.Pow(1-t, 3)*ly + 3*math.Pow(1-t, 2)*t*y1 + 3*(1-t)*math.Pow(t, 2)*y2 + math.Pow(t, 3)*y
+					pts = append(pts, gopdf.Point{X: ox + tx*scale, Y: oy + ty*scale})
+				}
+				lx, ly = x, y; i += 6
+			case "Q":
+				if i+3 >= len(tokens) { i = len(tokens); break }
+				x1, _ := strconv.ParseFloat(tokens[i], 64); y1, _ := strconv.ParseFloat(tokens[i+1], 64)
+				x,  _ := strconv.ParseFloat(tokens[i+2], 64); y,  _ := strconv.ParseFloat(tokens[i+3], 64)
+				if isRel { x1 += lx; y1 += ly; x += lx; y += ly }
+				for t := 0.25; t <= 1.0; t += 0.25 {
+					tx := math.Pow(1-t, 2)*lx + 2*(1-t)*t*x1 + math.Pow(t, 2)*x
+					ty := math.Pow(1-t, 2)*ly + 2*(1-t)*t*y1 + math.Pow(t, 2)*y
+					pts = append(pts, gopdf.Point{X: ox + tx*scale, Y: oy + ty*scale})
+				}
+				lx, ly = x, y; i += 4
+			case "A": i += 7
+			default: i++
 			}
-			lx, ly = x, y; i += 5
-		} else { i++ }
+		}
+		if len(pts) > 0 { results = append(results, PathResult{Points: pts, Closed: false}) }
 	}
-	return pts
+	return results
 }

pkg/learnnumber/tool.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"net/http"
 	"toolbox/pkg/base"
+	"toolbox/pkg/learnnumber/data"
 	"toolbox/pkg/learnnumber/logic"
 
 	"github.com/gin-gonic/gin"
@@ -18,14 +19,22 @@ func init() {
 func (t *learnNumberTool) ID() string          { return "learn-number" }
 func (t *learnNumberTool) Name() string        { return "幼儿数学助手" }
 func (t *learnNumberTool) Description() string { return "包含数图形、基础加减法等趣味数学练习" }
+func (t *learnNumberTool) Emoji() string       { return "🔢" }
 
 func (t *learnNumberTool) Init() error {
 	fmt.Println("Initializing Learn-Number tool...")
-	return nil
+	// 动态加载匿名对象
+	return data.LoadIcons("pkg/learnnumber/data/fruit.svg")
 }
 
 func (t *learnNumberTool) RegisterRoutes(r *gin.RouterGroup) {
 	r.POST("/counting", t.handleCounting)
+	r.GET("/categories", t.handleCategories)
+}
+
+func (t *learnNumberTool) handleCategories(c *gin.Context) {
+	// 返回分类信息供前端预览
+	c.JSON(http.StatusOK, data.IconCategories)
 }
 
 func (t *learnNumberTool) handleCounting(c *gin.Context) {
@@ -34,15 +43,10 @@ func (t *learnNumberTool) handleCounting(c *gin.Context) {
 		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
 		return
 	}
-
-	if req.TotalCount <= 0 { req.TotalCount = 20 }
-	if req.TotalCount > 30 { req.TotalCount = 30 }
-
 	pdfBytes, err := logic.GenerateCountingPDF(req)
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 		return
 	}
-
 	c.Data(http.StatusOK, "application/pdf", pdfBytes)
 }