feat(编辑能力): 完善缺字诊断，优化字体选择体验

assets/webui/ofdgo.css

@@ -273,12 +273,14 @@ a:focus-visible {
 	gap: 12px;
 	padding: 6px 8px;
 	line-height: 1.4;
-	overflow-wrap: anywhere;
 	cursor: pointer;
 }
 
 .font-listbox [role="option"] > span:first-child {
 	min-width: 0;
+	overflow: hidden;
+	text-overflow: ellipsis;
+	white-space: nowrap;
 }
 
 .font-option-source {

assets/webui/ofdgo.js

@@ -1,4 +1,4 @@
-import { CanvasEditor, canEditObject, objectEditReason } from "./ofdgo_edit.js";
+import { CanvasEditor, canEditObject, missingGlyphMessage, objectEditReason } from "./ofdgo_edit.js";
 import { FontManager, FontPicker } from "./ofdgo_font.js";
 
 const MM_TO_PX = 96 / 25.4;
@@ -1727,7 +1727,7 @@ async function loadWASM() {
 				if (data.ok) {
 					request.resolve(data.data);
 				} else {
-					const err = new Error(data.error);
+					const err = new Error(missingGlyphMessage(data.missingGlyphs) || data.error);
 					if (data.canceled) {
 						err.name = "AbortError";
 					}

assets/webui/ofdgo_edit.js

@@ -122,13 +122,21 @@ export function canEditObject(item, capability) {
 	return Boolean(item) && (item.items || [item]).every(object => Boolean(object.capabilities?.[capability]));
 }
 
+export function missingGlyphMessage(diagnostic) {
+	if (!diagnostic) return "";
+	const characters = Array.from(diagnostic.characters);
+	const sample = characters.slice(0, 8).map(char => /[\p{C}\p{Z}\p{M}]/u.test(char)
+		? `U+${char.codePointAt(0).toString(16).toUpperCase().padStart(4, "0")}` : char).join(" ");
+	return `字体缺字：${sample}${characters.length > 8 ? ` 等 ${characters.length} 字` : ""}，改选字体`;
+}
+
 export function objectEditReason(item) {
 	const reasons = (item?.items || (item ? [item] : [])).map(object => {
 		const reason = object.capabilities?.reason || "";
 		if (!reason) return "";
 		let message = "对象特性暂不支持";
-		if (reason.includes("embedded font")) message = "缺少内嵌字体";
-		else if (reason.includes("does not contain")) message = "字体缺字";
+		if (object.capabilities.missingGlyphs) message = missingGlyphMessage(object.capabilities.missingGlyphs);
+		else if (reason.includes("embedded font")) message = "缺少内嵌字体";
 		else if (reason.includes("color") || reason.includes("RGB")) message = "颜色样式暂不支持";
 		else if (reason.includes("draw parameter")) message = "绘制参数暂不支持";
 		else if (reason.includes("layer")) message = "图层特性暂不支持";

assets/webui/ofdgo_font.js

@@ -80,7 +80,7 @@ export class FontPicker {
 				label.textContent = source;
 				option.append(label);
 			}
-			option.title = font.name || font.fullName;
+			option.title = [...new Set([font.fullName, font.name].filter(Boolean))].join(" · ");
 			this.list.append(option);
 		}
 		if (!this.matches.length) {
@@ -100,9 +100,9 @@ export class FontPicker {
 
 	position() {
 		if (!this.open) return;
-		const rect = this.input.getBoundingClientRect();
+		const rect = this.input.parentElement.getBoundingClientRect();
 		if (rect.right <= 0 || rect.left >= window.innerWidth) { this.close(); return; }
-		const width = Math.min(Math.max(rect.width, 260), window.innerWidth - 16);
+		const width = Math.min(rect.width, window.innerWidth - 16);
 		Object.assign(this.list.style, { left: `${Math.max(8, Math.min(rect.left, window.innerWidth - width - 8))}px`,
 			top: `${rect.bottom + 4}px`, width: `${width}px`, maxHeight: `${Math.max(40, Math.min(280, window.innerHeight - rect.bottom - 12))}px` });
 	}

internal/webui/wasm.go

@@ -22,6 +22,7 @@ import (
 	"context"
 	"encoding/hex"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"image"
 	"io"
@@ -80,6 +81,7 @@ type apiResult struct {
 	OK            bool                     `json:"ok"`
 	Error         string                   `json:"error,omitempty"`
 	Data          any                      `json:"data,omitempty"`
+	MissingGlyphs *ofdgo.MissingGlyphError `json:"missingGlyphs,omitempty"`
 }
 
 // RunWASM 注册浏览器WASM接口并阻塞运行
@@ -167,7 +169,9 @@ func registerExportCallback(name string, fn func([]js.Value) (any, error)) {
 func callbackResult(fn func([]js.Value) (any, error), args []js.Value) any {
 	data, err := safeCall(fn, args)
 	if err != nil {
-		return encodeResult(apiResult{OK: false, Error: err.Error()})
+		result := apiResult{Error: err.Error()}
+		errors.As(err, &result.MissingGlyphs)
+		return encodeResult(result)
 	}
 	if result, ok := data.(js.Value); ok {
 		return result
@@ -698,6 +702,9 @@ func editorObjects(index int, text *ofdgo.PageText) ([]any, error) {
 				}
 				item := map[string]any{"id": id, "type": object.Type, "x": box.X, "y": box.Y, "width": box.W, "height": box.H, "order": order, "position": position.Index, "count": position.Count, "container": position.Container,
 					"capabilities": map[string]any{"update": capability.Update, "replaceFont": capability.ReplaceFont, "reflow": capability.Reflow, "layoutKnown": capability.LayoutKnown, "transform": capability.Transform, "arrange": capability.Arrange, "copy": capability.Copy, "delete": capability.Delete, "order": capability.Order, "reason": capability.Reason}}
+				if missing := capability.MissingGlyphs; missing != nil {
+					item["capabilities"].(map[string]any)["missingGlyphs"] = map[string]any{"fontID": missing.FontID, "characters": missing.Characters}
+				}
 				if object.Type == "ImageObject" && capability.Update {
 					full, err := object.ImageObject.ImageBounds()
 					if err != nil {

ofdgo_editor.go

@@ -858,16 +858,21 @@ func (e *Editor) LayoutText(obj *TextObject, value string, options TextLayout) e
 		lineHeight = math.Max(obj.Size, float64(int(ascender)-int(descender)+int(gap))*unit)
 	}
 	var codes []TextCode
+	var missing []rune
 	for _, paragraph := range strings.Split(value, "\n") {
 		runes := []rune(paragraph)
 		advances := make([]float64, len(runes))
 		for i, char := range runes {
 			glyph := sfnt.GlyphIndex(char)
 			if glyph == 0 {
-				return fmt.Errorf("font does not contain U+%04X", char)
+				missing = append(missing, char)
+				continue
 			}
 			advances[i] = float64(sfnt.GlyphAdvance(glyph)) * unit * hScale
 		}
+		if len(missing) != 0 {
+			continue
+		}
 		spaceTextAdvances(runes, advances, options.LetterSpacing)
 		for _, advance := range advances {
 			if !finite(advance) {
@@ -884,6 +889,9 @@ func (e *Editor) LayoutText(obj *TextObject, value string, options TextLayout) e
 			codes = append(codes, TextCode{X: ofdNumber(x), Y: ofdNumber(y), DeltaX: deltas, Value: escapeOFDText(string(runes[line[0]:line[1]]))})
 		}
 	}
+	if err := missingGlyphError(obj.Font, missing); err != nil {
+		return err
+	}
 	obj.TextCode = codes
 	obj.layout = nil
 	if options != (TextLayout{}) || e.objectOrigin(obj.ID) != nil {
@@ -918,6 +926,7 @@ func (e *Editor) prepareText(obj *TextObject) error {
 		}
 	}
 	obj.TextCode = append([]TextCode(nil), obj.TextCode...)
+	var missing []rune
 	x, y := "", ""
 	for i := range obj.TextCode {
 		code := &obj.TextCode[i]
@@ -939,7 +948,7 @@ func (e *Editor) prepareText(obj *TextObject) error {
 		runes := textCodeRunes(code.Value)
 		for _, char := range runes {
 			if sfnt.GlyphIndex(char) == 0 {
-				return fmt.Errorf("font does not contain U+%04X", char)
+				missing = append(missing, char)
 			}
 		}
 		for _, delta := range []string{code.DeltaX, code.DeltaY} {
@@ -957,7 +966,7 @@ func (e *Editor) prepareText(obj *TextObject) error {
 	if strings.Trim(obj.Text(), "\n") == "" {
 		return fmt.Errorf("text codes are empty")
 	}
-	return nil
+	return missingGlyphError(obj.Font, missing)
 }
 
 // creationDeltas 校验文字位移数组及g重复编码

ofdgo_editor_batch.go

@@ -57,7 +57,7 @@ func (e *Editor) Objects(page int, ids []string) ([]GraphicObject, error) {
 			return nil, err
 		}
 		if !capability.Copy {
-			return nil, fmt.Errorf("object %q cannot be copied: %s", editorObjectID(object), capability.Reason)
+			return nil, fmt.Errorf("object %q cannot be copied: %w", editorObjectID(object), capability.editError())
 		}
 		objects[i], err = cloneEditorObject(object)
 		if err != nil {
@@ -362,7 +362,7 @@ func (e *Editor) updateObjects(page int, objects []GraphicObject, geometry bool)
 				return err
 			}
 			if !capability.Transform || !geometry && !e.sourceRGB() {
-				return fmt.Errorf("object %q is read-only for this operation: %s", ids[i], capability.Reason)
+				return fmt.Errorf("object %q is read-only for this operation: %w", ids[i], capability.editError())
 			}
 		}
 		if geometry && e.originalPage(page) {
@@ -498,7 +498,7 @@ func (e *Editor) DeleteObjects(page int, ids []string) error {
 			return err
 		}
 		if !capability.Delete {
-			return fmt.Errorf("object %q cannot be deleted: %s", id, capability.Reason)
+			return fmt.Errorf("object %q cannot be deleted: %w", id, capability.editError())
 		}
 	}
 	layers := copyEditorPage(e.pages[page]).Content.Layer
@@ -568,7 +568,7 @@ func (e *Editor) objectBounds(page int, objects []GraphicObject) ([]Box, error)
 			return nil, err
 		}
 		if !capability.Arrange {
-			return nil, fmt.Errorf("object %q cannot be arranged: %s", editorObjectID(object), capability.Reason)
+			return nil, fmt.Errorf("object %q cannot be arranged: %w", editorObjectID(object), capability.editError())
 		}
 	}
 	reader, err := e.Reader()

ofdgo_editor_open.go

@@ -17,6 +17,7 @@ package ofdgo
 import (
 	"bytes"
 	"encoding/xml"
+	"errors"
 	"fmt"
 	"image"
 	"io"
@@ -59,6 +60,7 @@ type editorSourcePage struct {
 // ObjectCapabilities 已有对象可执行的操作，Reason说明受限原因
 // Update表示完整替换内容，ReplaceFont表示可显式替换文字字体，Transform表示保留文字定位的几何变换，Order仅限同一图层或末级页块
 // Arrange表示可准确度量对齐与旋转范围；Reflow表示可重排文字，LayoutKnown表示段落选项可恢复
+// MissingGlyphs提供缺字导致操作受限时的结构化诊断
 type ObjectCapabilities struct {
 	Update        bool
 	ReplaceFont   bool
@@ -70,6 +72,16 @@ type ObjectCapabilities struct {
 	Delete        bool
 	Order         bool
 	Reason        string
+	MissingGlyphs *MissingGlyphError
+}
+
+// editError 将操作受限原因转为错误，保留可供调用方识别的缺字诊断
+// 返回: error 受限原因
+func (c ObjectCapabilities) editError() error {
+	if c.MissingGlyphs != nil {
+		return c.MissingGlyphs
+	}
+	return errors.New(c.Reason)
 }
 
 // PageCapabilities 页面可执行的操作，Insert表示可以添加RGB对象；新增空白页面始终可用
@@ -351,10 +363,12 @@ func (e *Editor) ObjectCapabilities(page int, id string) (ObjectCapabilities, er
 	all.Order = editorContainerOrderable(node.parent)
 	if _, err := e.prepareObject(id, object); err != nil {
 		all.Update, all.Reflow, all.Copy, all.Reason = false, false, false, err.Error()
+		errors.As(err, &all.MissingGlyphs)
 	}
 	if !e.sourceRGB() {
 		all.ReplaceFont = false
 		all.Update, all.Reflow, all.Copy, all.Reason = false, false, false, "document uses a non-RGB default color space"
+		all.MissingGlyphs = nil
 	}
 	if object.Type == "TextObject" {
 		all.Arrange = all.Update

ofdgo_editor_text.go

@@ -15,11 +15,47 @@
 package ofdgo
 
 import (
+	"fmt"
 	"strings"
 
 	"github.com/go-text/typesetting/segmenter"
 )
 
+// MissingGlyphError 字体缺字错误，FontID为OFD字体资源标识，Characters按首次出现顺序保留不重复的缺失字符
+// 可通过errors.As从编辑错误中取得，不表示字体缺失或文件损坏
+type MissingGlyphError struct {
+	FontID     string `json:"fontID"`
+	Characters string `json:"characters"`
+}
+
+// Error 返回缺失字符的Unicode码点
+// 返回: string 错误描述
+func (e *MissingGlyphError) Error() string {
+	var codes []string
+	for _, char := range e.Characters {
+		codes = append(codes, fmt.Sprintf("U+%04X", char))
+	}
+	return fmt.Sprintf("font %q does not contain %s", e.FontID, strings.Join(codes, ", "))
+}
+
+// missingGlyphError 汇总缺失字符，无缺字时返回nil
+// 入参: id 字体资源标识, characters 缺失字符
+// 返回: error 缺字诊断
+func missingGlyphError(id string, characters []rune) error {
+	if len(characters) == 0 {
+		return nil
+	}
+	seen := make(map[rune]bool)
+	var value strings.Builder
+	for _, char := range characters {
+		if !seen[char] {
+			seen[char] = true
+			value.WriteRune(char)
+		}
+	}
+	return &MissingGlyphError{FontID: id, Characters: value.String()}
+}
+
 // TextLayout 本地横向段落选项，Wrap按CTM变换前的边界宽度折行，Align为left、center、right或justify
 // LineHeight为毫米单位的基线间距，0使用字体度量；LetterSpacing为字素间的附加毫米间距，可为负
 // 零值保持显式换行和左对齐