fix(agent): 图片尺寸 - 修复比例 preset 映射

backend/internal/app/image_parameters.go

@@ -262,6 +262,36 @@ func imageParameterValue(p protocol.ImageParameter, value any) any {
 	return value
 }
 
+func imageParameterUnsupportedMessage(p protocol.ImageParameter) string {
+	message := "图片参数超出支持范围：" + p.Label
+	if len(p.Values) > 0 {
+		values := make([]string, 0, min(len(p.Values), 12))
+		for _, value := range p.Values[:min(len(p.Values), 12)] {
+			values = append(values, fmt.Sprint(value))
+		}
+		message += "；支持值：" + strings.Join(values, "、")
+		if len(p.Values) > len(values) {
+			message += "等"
+		}
+	} else if p.Min != nil || p.Max != nil {
+		message += fmt.Sprintf("；范围：%s-%s", formatImageParameterBound(p.Min), formatImageParameterBound(p.Max))
+	}
+	if p.Default != nil {
+		message += "；默认值：" + fmt.Sprint(p.Default)
+	}
+	if p.Binding == "aspectRatio" && p.Encoding == "pixels" {
+		message += "；若使用比例，按 model_list 的 imageSize.presets 选择对应像素尺寸"
+	}
+	return message
+}
+
+func formatImageParameterBound(value *float64) string {
+	if value == nil {
+		return "不限"
+	}
+	return strconv.FormatFloat(*value, 'f', -1, 64)
+}
+
 func imageParameterAdmissionError(field, issue, message string) error {
 	return NewModelError(ErrCodeModelCapabilityNotSupported, message).WithDetails(map[string]any{
 		"field":   field,
@@ -285,7 +315,7 @@ func resolveImageParameterValues(parameters []protocol.ImageParameter, values ma
 		}
 		value = imageParameterValue(p, value)
 		if !p.Accepts(value) {
-			return nil, imageParameterAdmissionError(p.Name, "unsupported_value", "图片参数超出支持范围："+p.Label)
+			return nil, imageParameterAdmissionError(p.Name, "unsupported_value", imageParameterUnsupportedMessage(p))
 		}
 		if value != nil && value != "" {
 			result[name] = value

backend/internal/app/image_parameters_test.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 	"time"
 
@@ -35,6 +36,36 @@ func imageParameterTestAdapter(t *testing.T, packageID, providerID string) proto
 	return nil
 }
 
+func TestImageParameterRatioUsesDeclaredPixelPreset(t *testing.T) {
+	profile := DefaultModelCapabilityConfigForModel("openai-image", "GPT Image 2.5")
+	profile.Image.Parameters = []protocol.ImageParameter{{
+		Name: "size", Label: "画幅 / 尺寸", Type: "string",
+		Values: []any{"auto", "1824x1024", "1024x1824", "1024x1024"}, Default: "1824x1024",
+		Binding: "aspectRatio", Encoding: "pixels", Pricing: true,
+	}}
+	profile.Image.Size = ImageSizeConfig{
+		Parameter: "size", Values: []string{"auto", "1824x1024", "1024x1824", "1024x1024"}, Default: "1824x1024",
+		Presets: []ImageSizePreset{
+			{Tier: "1k", Ratio: "16:9", Size: "1824x1024"},
+			{Tier: "1k", Ratio: "9:16", Size: "1024x1824"},
+			{Tier: "1k", Ratio: "1:1", Size: "1024x1024"},
+		},
+	}
+	if got := imageSizeValueForDeclaredPreset(profile.Image, "16:9", ""); got != "1824x1024" {
+		t.Fatalf("ratio was not encoded by the declared preset: %q", got)
+	}
+	if got := imageSizeValueForDeclaredPreset(profile.Image, "1024x1824", ""); got != "1024x1824" {
+		t.Fatalf("pixel preset was not preserved: %q", got)
+	}
+	values := map[string]any{"size": imageSizeValueForDeclaredPreset(profile.Image, "16:9", "")}
+	if _, err := resolveImageParameterValues(profile.Image.Parameters, values); err != nil {
+		t.Fatalf("encoded preset was rejected by image parameter admission: %v", err)
+	}
+	if _, err := resolveImageParameterValues(profile.Image.Parameters, map[string]any{"size": "16:9"}); err == nil || !strings.Contains(err.Error(), "支持值") || !strings.Contains(err.Error(), "imageSize.presets") {
+		t.Fatalf("unsupported ratio error lacks actionable correction guidance: %v", err)
+	}
+}
+
 func TestImageParametersResolutionOnlyAndLogicalReconciliation(t *testing.T) {
 	a := imageParameterTestAdapter(t, "google-gemini-image", "gemini-image")
 	registry, err := protocol.NewRegistry(a)

backend/internal/app/model_capability_validate.go

@@ -490,6 +490,20 @@ func validateImagePresetSelection(profile *ImageCapabilityConfig, quality, ratio
 	return newModelCapabilityArgumentError("size", "unsupported_value", BadAuthRequest("当前分辨率不支持所选图片宽高比"))
 }
 
+func imageSizeValueForDeclaredPreset(profile *ImageCapabilityConfig, size string, quality string) string {
+	if profile == nil {
+		return ""
+	}
+	preset, ok := declaredImageSizePreset(profile.Size.Presets, size, quality, imagePresetDefaultTier(profile))
+	if !ok {
+		return ""
+	}
+	if profile.Size.Parameter == "size" {
+		return strings.TrimSpace(preset.Size)
+	}
+	return normalizeDeclaredImageRatio(preset.Ratio)
+}
+
 // imageSizeRatioForDeclaredPreset 把已声明的 preset 像素值还原成它对应的比例。比例型线路
 // 会把画布比例换算成 preset 像素值（OpenAI Images 只收 WIDTHxHEIGHT），换算结果必须继续
 // 通过同一套尺寸与分辨率校验。只认当前档位的 preset，避免用低档价格取到高档像素。

backend/internal/app/task_creation.go

@@ -533,8 +533,8 @@ func (s *Service) resolveSystemChannelModelSelection(input map[string]any, taskT
 		}
 		if value, ok := values["size"]; ok && capabilitySpec != nil && capabilityImageSizePresetMatches(*capabilitySpec, value, values) {
 			values = maps.Clone(values)
-			if ratio := imageSizeRatioForDeclaredPreset(capabilityConfig.Image, fmt.Sprint(value), fmt.Sprint(values["imageResolution"])); ratio != "" {
-				values["size"] = ratio
+			if encoded := imageSizeValueForDeclaredPreset(capabilityConfig.Image, fmt.Sprint(value), stringValue(values["imageResolution"])); encoded != "" {
+				values["size"] = encoded
 			}
 		}
 		resolved, parameterErr := resolveImageParameterValues(parameters, values)

backend/internal/app/task_creation_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"yingce/backend/internal/model"
+	"yingce/backend/internal/protocol"
 	"yingce/backend/internal/repository"
 
 	"gorm.io/driver/sqlite"
@@ -475,6 +476,46 @@ func TestImageResolutionPricingOnSystemChannel(t *testing.T) {
 	}
 }
 
+func TestParameterizedOpenAIAspectPresetSystemChannelPersistsPixelExecutionSize(t *testing.T) {
+	profile := DefaultModelCapabilityConfigForModel(string(model.ChannelInterfaceOpenAIImage), "GPT Image 2.5")
+	profile.Image.Parameters = []protocol.ImageParameter{{
+		Name: "size", Label: "画幅 / 尺寸", Type: "string",
+		Values: []any{"auto", "1824x1024", "1024x1824", "1024x1024"}, Default: "1824x1024",
+		Pricing: true, Binding: "aspectRatio", Encoding: "pixels",
+	}}
+	profile.Image.Size = ImageSizeConfig{
+		Parameter: "size", Values: []string{"auto", "1824x1024", "1024x1824", "1024x1024"}, Default: "1824x1024",
+		Presets: []ImageSizePreset{
+			{Tier: "1k", Ratio: "16:9", Size: "1824x1024", Width: 1824, Height: 1024},
+			{Tier: "1k", Ratio: "9:16", Size: "1024x1824", Width: 1024, Height: 1824},
+			{Tier: "1k", Ratio: "1:1", Size: "1024x1024", Width: 1024, Height: 1024},
+		},
+	}
+	if err := projectImageParameters(profile.Image); err != nil {
+		t.Fatal(err)
+	}
+	svc, _, channel, channelModel := createSystemChannelSelectionFixture(t, "image", model.ChannelInterfaceOpenAIImage, profile, []model.ChannelModelPriceTier{
+		newSelectionPriceTier("tier-1k", `{"size":"1824x1024"}`, "provider-1k", "fixed_request"),
+	})
+	input := map[string]any{
+		"mode": "image",
+		"config": map[string]any{
+			"channelId":       channel.ID,
+			"model":           channelModel.ModelKey,
+			"imageParameters": map[string]any{"size": "16:9"},
+		},
+	}
+	resolved, err := svc.resolveSystemChannelModelSelection(input, "canvas_image", "")
+	if err != nil {
+		t.Fatalf("resolve error = %v", err)
+	}
+	config := resolved["config"].(map[string]any)
+	parameters := config["imageParameters"].(map[string]any)
+	if parameters["size"] != "1824x1024" || config["size"] != "1824x1024" {
+		t.Fatalf("parameterized size = %#v, config = %#v", parameters["size"], config["size"])
+	}
+}
+
 func TestOpenAIAspectPresetSystemChannelPersistsPixelExecutionSize(t *testing.T) {
 	profile := DefaultModelCapabilityConfigForModel(string(model.ChannelInterfaceOpenAIImage), "gpt-image-2.5-4k")
 	profile.Image.Size = ImageSizeConfig{