fix(inference): 回退为 OpenAI 兼容同步 Images API，恢复图片编辑功能

- 使用标准 POST /images/generations 端点（suchuang.vip 兼容）
- 恢复 EditImages 的 multipart/form-data 实现
- 移除 yuntts 异步 submit/poll 流程
- 配置精简: base_url / api_key / model / width / height / quality

backend/internal/service/inference.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"crypto/rand"
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"image"
@@ -11,9 +12,9 @@ import (
 	"image/png"
 	"io"
 	"log"
+	"mime/multipart"
 	"net/http"
 	"strings"
-	"time"
 
 	"gen2d/internal/config"
 )
@@ -26,47 +27,28 @@ func InitImageGenConfig(cfg config.ImageGenConfig) {
 	imgCfg = cfg
 }
 
-// ======================== GPT Image 2 API 类型 ========================
+// ======================== OpenAI 兼容 Images API 类型 ========================
 
-// genSubmitReq 提交生图任务请求体。
+// imageGenRequest OpenAI 兼容文生图请求体。
-type genSubmitReq struct {
+type imageGenRequest struct {
-	Prompt          string   `json:"prompt"`
+	Model   string `json:"model"`
-	AspectRatio     string   `json:"aspect_ratio,omitempty"`
+	Prompt  string `json:"prompt"`
-	ReferenceImages []string `json:"reference_images,omitempty"`
+	N       int    `json:"n,omitempty"`
-	XChannel        string   `json:"x_channel,omitempty"`
+	Size    string `json:"size,omitempty"`
+	Quality string `json:"quality,omitempty"`
 }
 
-// genSubmitResp 提交生图任务响应体。
+// imageGenResponse OpenAI 兼容文生图响应体。
-type genSubmitResp struct {
+type imageGenResponse struct {
-	Code    int    `json:"code"`
+	Data []struct {
-	Message string `json:"message"`
+		URL     string `json:"url"`
-	Data    struct {
+		B64JSON string `json:"b64_json"`
-		TaskID string `json:"task_id"`
-		Status string `json:"status"`
-	} `json:"data"`
-}
-
-// genStatusReq 查询任务状态请求体。
-type genStatusReq struct {
-	TaskID string `json:"task_id"`
-}
-
-// genStatusResp 查询任务状态响应体。
-type genStatusResp struct {
-	Code    int    `json:"code"`
-	Message string `json:"message"`
-	Data    struct {
-		TaskID         string `json:"task_id"`
-		Status         string `json:"status"`
-		Progress       int    `json:"progress"`
-		ResultImageURL string `json:"result_image_url"`
-		ErrorMessage   string `json:"error_message"`
 	} `json:"data"`
 }
 
 // ======================== 文生图 ========================
 
-// GenerateImages 通过 GPT Image 2 异步 API 生成图片，未配置 key 时回退到 mock。
+// GenerateImages 调用 OpenAI 兼容 Images API 生成图片，未配置 key 时回退 mock。
 func GenerateImages(ctx context.Context, prompt string, params AssetParams) ([]GeneratedImage, error) {
 	count := 1
 	if params.Frames.Directions > 0 && params.Frames.FramesPerDirection > 0 {
@@ -74,8 +56,13 @@ func GenerateImages(ctx context.Context, prompt string, params AssetParams) ([]G
 	}
 
 	if imgCfg.APIKey != "" {
-		log.Println("[inference] using image gen async API")
+		width, height := imgCfg.Width, imgCfg.Height
-		return generateAsync(ctx, prompt, count, nil)
+		if params.Resolution > 0 {
+			width = params.Resolution
+			height = params.Resolution
+		}
+		log.Println("[inference] calling image gen API")
+		return callImageAPI(ctx, prompt, count, width, height)
 	}
 
 	size := params.Resolution
@@ -86,170 +73,22 @@ func GenerateImages(ctx context.Context, prompt string, params AssetParams) ([]G
 	return generateMockImages(size, count)
 }
 
-// ======================== 图片编辑 ========================
+// callImageAPI 调用 OpenAI 兼容 Images API。
-
+func callImageAPI(ctx context.Context, prompt string, count, width, height int) ([]GeneratedImage, error) {
-// EditImages 图片编辑接口，以参考图模式提交 GPT Image 2 编辑任务。
+	reqBody := imageGenRequest{
-func EditImages(ctx context.Context, imageData []byte, prompt string, count int) ([]GeneratedImage, error) {
+		Model:   imgCfg.Model,
-	if imgCfg.APIKey == "" {
+		Prompt:  prompt,
-		return nil, fmt.Errorf("image API key not configured")
+		N:       count,
-	}
+		Size:    fmt.Sprintf("%dx%d", width, height),
-	log.Println("[inference] using image gen async API for edit")
+		Quality: imgCfg.Quality,
-	// 暂不支持参考图 URL 模式，提示用户
-	return nil, fmt.Errorf("image edit with reference image: not yet implemented for async API")
-}
-
-// ======================== 异步核心 ========================
-
-// generateAsync 并行提交 count 个任务，轮询完成后下载图片。
-func generateAsync(ctx context.Context, prompt string, count int, refImages []string) ([]GeneratedImage, error) {
-	type submitResult struct {
-		index  int
-		taskID string
-		err    error
-	}
-	results := make(chan submitResult, count)
-	for i := 0; i < count; i++ {
-		go func(idx int) {
-			taskID, err := submitTask(ctx, prompt, refImages)
-			results <- submitResult{index: idx, taskID: taskID, err: err}
-		}(i)
-	}
-
-	taskIDs := make([]string, count)
-	for i := 0; i < count; i++ {
-		r := <-results
-		if r.err != nil {
-			return nil, fmt.Errorf("submit task %d: %w", r.index, r.err)
-		}
-		taskIDs[r.index] = r.taskID
-	}
-
-	type imageResult struct {
-		index int
-		image GeneratedImage
-		err   error
-	}
-	imgResults := make(chan imageResult, count)
-	for i, tid := range taskIDs {
-		go func(idx int, taskID string) {
-			img, err := pollAndDownload(ctx, taskID)
-			imgResults <- imageResult{index: idx, image: img, err: err}
-		}(i, tid)
-	}
-
-	images := make([]GeneratedImage, count)
-	for i := 0; i < count; i++ {
-		r := <-imgResults
-		if r.err != nil {
-			return nil, fmt.Errorf("task %d: %w", r.index, r.err)
-		}
-		images[r.index] = r.image
-	}
-
-	return images, nil
-}
-
-// submitTask 提交生图任务，返回 taskID。
-func submitTask(ctx context.Context, prompt string, refImages []string) (string, error) {
-	reqBody := genSubmitReq{
-		Prompt:          prompt,
-		AspectRatio:     imgCfg.AspectRatio,
-		ReferenceImages: refImages,
-		XChannel:        imgCfg.XChannel,
 	}
 
 	body, err := json.Marshal(reqBody)
 	if err != nil {
-		return "", fmt.Errorf("marshal: %w", err)
+		return nil, fmt.Errorf("marshal request: %w", err)
 	}
 
-	url := strings.TrimRight(imgCfg.BaseURL, "/") + "/gpt-image2/generate"
+	url := strings.TrimRight(imgCfg.BaseURL, "/") + "/images/generations"
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
-	if err != nil {
-		return "", fmt.Errorf("create request: %w", err)
-	}
-	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("Authorization", "Bearer "+imgCfg.APIKey)
-
-	resp, err := http.DefaultClient.Do(req)
-	if err != nil {
-		return "", fmt.Errorf("send: %w", err)
-	}
-	defer resp.Body.Close()
-
-	var sr genSubmitResp
-	if err := json.NewDecoder(resp.Body).Decode(&sr); err != nil {
-		return "", fmt.Errorf("decode: %w", err)
-	}
-
-	if sr.Code != 200 {
-		return "", fmt.Errorf("submit failed: %s", sr.Message)
-	}
-
-	log.Printf("[inference] task submitted: %s", sr.Data.TaskID)
-	return sr.Data.TaskID, nil
-}
-
-// pollAndDownload 轮询任务直到完成，下载图片。
-func pollAndDownload(ctx context.Context, taskID string) (GeneratedImage, error) {
-	pollInterval := imgCfg.PollInterval
-	if pollInterval <= 0 {
-		pollInterval = 3
-	}
-	maxWait := imgCfg.PollMaxWait
-	if maxWait <= 0 {
-		maxWait = 120
-	}
-
-	deadline := time.Now().Add(time.Duration(maxWait) * time.Second)
-	ticker := time.NewTicker(time.Duration(pollInterval) * time.Second)
-	defer ticker.Stop()
-
-	for {
-		select {
-		case <-ctx.Done():
-			return GeneratedImage{}, ctx.Err()
-		case <-ticker.C:
-			st, err := queryStatus(ctx, taskID)
-			if err != nil {
-				return GeneratedImage{}, fmt.Errorf("query status: %w", err)
-			}
-
-			switch st.Data.Status {
-			case "completed":
-				log.Printf("[inference] task %s completed, downloading", taskID)
-				data, err := downloadResult(ctx, st.Data.ResultImageURL)
-				if err != nil {
-					return GeneratedImage{}, fmt.Errorf("download: %w", err)
-				}
-				return GeneratedImage{Data: data, Format: "png"}, nil
-
-			case "failed":
-				errMsg := st.Data.ErrorMessage
-				if errMsg == "" {
-					errMsg = "unknown error"
-				}
-				return GeneratedImage{}, fmt.Errorf("generation failed: %s", errMsg)
-
-			default:
-				log.Printf("[inference] task %s status=%s progress=%d", taskID, st.Data.Status, st.Data.Progress)
-			}
-
-			if time.Now().After(deadline) {
-				return GeneratedImage{}, fmt.Errorf("poll timeout after %ds", maxWait)
-			}
-		}
-	}
-}
-
-// queryStatus 查询任务状态。
-func queryStatus(ctx context.Context, taskID string) (*genStatusResp, error) {
-	body, err := json.Marshal(genStatusReq{TaskID: taskID})
-	if err != nil {
-		return nil, fmt.Errorf("marshal: %w", err)
-	}
-
-	url := strings.TrimRight(imgCfg.BaseURL, "/") + "/gpt-image2/status"
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
 	if err != nil {
 		return nil, fmt.Errorf("create request: %w", err)
@@ -259,48 +98,125 @@ func queryStatus(ctx context.Context, taskID string) (*genStatusResp, error) {
 
 	resp, err := http.DefaultClient.Do(req)
 	if err != nil {
-		return nil, fmt.Errorf("send: %w", err)
+		return nil, fmt.Errorf("send request: %w", err)
 	}
 	defer resp.Body.Close()
 
-	var sr genStatusResp
+	if resp.StatusCode != http.StatusOK {
-	if err := json.NewDecoder(resp.Body).Decode(&sr); err != nil {
+		b, _ := io.ReadAll(io.LimitReader(resp.Body, 4096))
-		return nil, fmt.Errorf("decode: %w", err)
+		return nil, fmt.Errorf("image api error %d: %s", resp.StatusCode, string(b))
 	}
 
-	if sr.Code != 200 {
+	return parseImageResponse(ctx, resp.Body, width, height)
-		return nil, fmt.Errorf("status query failed: %s", sr.Message)
-	}
-
-	return &sr, nil
 }
 
-// downloadResult 下载生成的图片。
+// parseImageResponse 解析 OpenAI 兼容图片响应（b64_json 或 url）。
-func downloadResult(ctx context.Context, imageURL string) ([]byte, error) {
+func parseImageResponse(ctx context.Context, r io.Reader, width, height int) ([]GeneratedImage, error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, imageURL, nil)
+	var genResp imageGenResponse
+	if err := json.NewDecoder(r).Decode(&genResp); err != nil {
+		return nil, fmt.Errorf("decode response: %w", err)
+	}
+
+	images := make([]GeneratedImage, 0, len(genResp.Data))
+	for i, d := range genResp.Data {
+		var data []byte
+		switch {
+		case d.B64JSON != "":
+			var err error
+			data, err = base64.StdEncoding.DecodeString(d.B64JSON)
+			if err != nil {
+				return nil, fmt.Errorf("decode base64 image %d: %w", i, err)
+			}
+		case d.URL != "":
+			var err error
+			data, err = downloadImage(ctx, d.URL)
+			if err != nil {
+				return nil, fmt.Errorf("download image %d: %w", i, err)
+			}
+		default:
+			return nil, fmt.Errorf("image %d: no data or url in response", i)
+		}
+		images = append(images, GeneratedImage{
+			Data:   data,
+			Width:  width,
+			Height: height,
+			Format: "png",
+		})
+	}
+	return images, nil
+}
+
+// downloadImage 从 URL 下载图片数据。
+func downloadImage(ctx context.Context, url string) ([]byte, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
 	if err != nil {
 		return nil, fmt.Errorf("create download request: %w", err)
 	}
-
 	resp, err := http.DefaultClient.Do(req)
 	if err != nil {
 		return nil, fmt.Errorf("download: %w", err)
 	}
 	defer resp.Body.Close()
-
 	if resp.StatusCode != http.StatusOK {
 		return nil, fmt.Errorf("download status %d", resp.StatusCode)
 	}
-
 	return io.ReadAll(resp.Body)
 }
 
+// ======================== 图片编辑 ========================
+
+// EditImages 图片编辑接口，调用 OpenAI 兼容 Images Edits API（multipart/form-data）。
+func EditImages(ctx context.Context, imageData []byte, prompt string, count int) ([]GeneratedImage, error) {
+	if imgCfg.APIKey == "" {
+		return nil, fmt.Errorf("image API key not configured")
+	}
+
+	var buf bytes.Buffer
+	writer := multipart.NewWriter(&buf)
+
+	part, err := writer.CreateFormFile("image", "image.png")
+	if err != nil {
+		return nil, fmt.Errorf("create form file: %w", err)
+	}
+	if _, err := part.Write(imageData); err != nil {
+		return nil, fmt.Errorf("write image data: %w", err)
+	}
+
+	writer.WriteField("prompt", prompt)
+	writer.WriteField("model", imgCfg.Model)
+	writer.WriteField("n", fmt.Sprintf("%d", count))
+	writer.WriteField("size", fmt.Sprintf("%dx%d", imgCfg.Width, imgCfg.Height))
+
+	if err := writer.Close(); err != nil {
+		return nil, fmt.Errorf("close multipart writer: %w", err)
+	}
+
+	url := strings.TrimRight(imgCfg.BaseURL, "/") + "/images/edits"
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, &buf)
+	if err != nil {
+		return nil, fmt.Errorf("create request: %w", err)
+	}
+	req.Header.Set("Content-Type", writer.FormDataContentType())
+	req.Header.Set("Authorization", "Bearer "+imgCfg.APIKey)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("send request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		b, _ := io.ReadAll(io.LimitReader(resp.Body, 4096))
+		return nil, fmt.Errorf("image edit api error %d: %s", resp.StatusCode, string(b))
+	}
+
+	return parseImageResponse(ctx, resp.Body, imgCfg.Width, imgCfg.Height)
+}
+
 // ======================== 质检 ========================
 
-// QualityChecker 质检函数，可替换用于测试。
 var QualityChecker = defaultCheckQuality
 
-// CheckQuality 调用当前 QualityChecker。
 func CheckQuality(ctx context.Context, images []GeneratedImage, style map[string]string) (bool, string, error) {
 	return QualityChecker(ctx, images, style)
 }