feat: 引入 Eino 框架，实现四阶段生成管线

基于 compose.Graph 编排 PromptBuilder → AssetGenerator → QualitySupervisor → FormatAdapter，含质检重试分支（最多 3 次）和降级输出。推理层提供 mock 模式，可替换为真实 API。
2026-05-24 13:21:11 +08:00
parent 2601af6da6
commit 9be4b16bdc
7 changed files with 696 additions and 1 deletions
@@ -0,0 +1,188 @@
+package service
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/cloudwego/eino/compose"
+)
+
+// PromptBuilder 节点：接收输入，输出三段式提示词
+var promptBuilderNode = compose.InvokableLambda(func(ctx context.Context, in PipelineInput) (string, error) {
+	return buildPrompt(in), nil
+})
+
+// promptBuilderPreHandler 首次运行时保存输入到 state；重试时注入 RejectReason
+func promptBuilderPreHandler(ctx context.Context, in PipelineInput, state *PipelineState) (PipelineInput, error) {
+	if state.RetryCount == 0 {
+		state.Input = in
+	} else if state.RejectReason != "" {
+		in.RejectReason = state.RejectReason
+	}
+	return in, nil
+}
+
+// promptBuilderPostHandler 将提示词写入全局状态
+func promptBuilderPostHandler(ctx context.Context, out string, state *PipelineState) (string, error) {
+	state.FinalPrompt = out
+	return out, nil
+}
+
+// AssetGenerator 节点：调用 AI 推理 API 出图
+var assetGeneratorNode = compose.InvokableLambda(func(ctx context.Context, prompt string) ([]GeneratedImage, error) {
+	var params AssetParams
+	_ = compose.ProcessState[*PipelineState](ctx, func(_ context.Context, state *PipelineState) error {
+		params = state.Input.Params
+		return nil
+	})
+	return GenerateImages(ctx, prompt, params)
+})
+
+// assetGeneratorPostHandler 将原始图片写入全局状态
+func assetGeneratorPostHandler(ctx context.Context, out []GeneratedImage, state *PipelineState) ([]GeneratedImage, error) {
+	state.RawImages = out
+	return out, nil
+}
+
+// QualitySupervisor 节点：质检，输出 PipelineInput 供下游节点消费。
+// 将图片存入 state，设置路由目标 NextNode。
+var qualitySupervisorNode = compose.InvokableLambda(func(ctx context.Context, images []GeneratedImage) (PipelineInput, error) {
+	var input PipelineInput
+	err := compose.ProcessState[*PipelineState](ctx, func(_ context.Context, state *PipelineState) error {
+		// 保存图片到状态
+		state.RawImages = images
+
+		// 质检
+		style := mergeStyle(state.Input.ProjectStyle, state.Input.TaskStyle)
+		pass, reason, checkErr := CheckQuality(ctx, images, style)
+		if checkErr != nil {
+			return fmt.Errorf("quality check: %w", checkErr)
+		}
+
+		state.PassQuality = pass
+		if !pass {
+			state.RejectReason = reason
+		}
+
+		// 决定路由
+		if pass {
+			state.NextNode = nodeFormatAdapter
+		} else if state.RetryCount >= 3 {
+			state.NextNode = nodeFormatAdapter // 超过重试次数，降级输出
+		} else {
+			state.RetryCount++
+			state.NextNode = nodePromptBuilder // 重生成
+		}
+
+		input = state.Input
+		return nil
+	})
+	if err != nil {
+		return PipelineInput{}, err
+	}
+	return input, nil
+})
+
+// formatAdapterNode 节点：从 state 读取图片，格式转换，组装输出
+var formatAdapterNode = compose.InvokableLambda(func(ctx context.Context, input PipelineInput) (PipelineOutput, error) {
+	var images []GeneratedImage
+	_ = compose.ProcessState[*PipelineState](ctx, func(_ context.Context, state *PipelineState) error {
+		images = state.RawImages
+		return nil
+	})
+
+	assets := make([]Asset, len(images))
+	for i, img := range images {
+		assets[i] = Asset{
+			Data:   img.Data,
+			Format: img.Format,
+			URL:    fmt.Sprintf("output/%d.%s", i, img.Format),
+		}
+	}
+
+	resolution := input.Params.Resolution
+	if resolution <= 0 {
+		resolution = 64
+	}
+
+	metadata := AssetMetadata{
+		FrameWidth:  resolution,
+		FrameHeight: resolution,
+		FrameCount:  len(images),
+		Directions:  input.Params.Frames.Directions,
+	}
+
+	return PipelineOutput{
+		Assets:   assets,
+		Metadata: metadata,
+	}, nil
+})
+
+// buildPrompt 构建三段式提示词
+func buildPrompt(in PipelineInput) string {
+	var parts []string
+
+	// 【主题】
+	parts = append(parts, fmt.Sprintf("【主题】%s", in.Prompt))
+
+	// 【约束】
+	constraints := buildConstraints(in)
+	parts = append(parts, fmt.Sprintf("【约束】%s", constraints))
+
+	// 【内容】
+	content := buildContent(in)
+	parts = append(parts, fmt.Sprintf("【内容】%s", content))
+
+	return strings.Join(parts, "\n")
+}
+
+// buildConstraints 合并风格 + 负面提示词 + 重试原因
+func buildConstraints(in PipelineInput) string {
+	style := mergeStyle(in.ProjectStyle, in.TaskStyle)
+
+	var parts []string
+	for k, v := range style {
+		parts = append(parts, fmt.Sprintf("%s: %s", k, v))
+	}
+
+	if in.RejectReason != "" {
+		parts = append(parts, fmt.Sprintf("上次质检问题：%s", in.RejectReason))
+	}
+
+	if len(parts) == 0 {
+		return "无特殊约束"
+	}
+	return strings.Join(parts, "; ")
+}
+
+// buildContent 构建技术参数段
+func buildContent(in PipelineInput) string {
+	var parts []string
+	parts = append(parts, fmt.Sprintf("素材类型: %s", in.AssetType))
+	if in.Params.Resolution > 0 {
+		parts = append(parts, fmt.Sprintf("分辨率: %d", in.Params.Resolution))
+	}
+	if in.Params.Frames.Directions > 0 {
+		parts = append(parts, fmt.Sprintf("方向数: %d", in.Params.Frames.Directions))
+	}
+	if in.Params.Frames.FramesPerDirection > 0 {
+		parts = append(parts, fmt.Sprintf("每方向帧数: %d", in.Params.Frames.FramesPerDirection))
+	}
+	if in.Params.Format != "" {
+		parts = append(parts, fmt.Sprintf("输出格式: %s", in.Params.Format))
+	}
+	return strings.Join(parts, "; ")
+}
+
+// mergeStyle 合并工程风格与任务风格覆盖，任务同名键覆盖工程
+func mergeStyle(projectStyle, taskStyle map[string]string) map[string]string {
+	result := make(map[string]string)
+	for k, v := range projectStyle {
+		result[k] = v
+	}
+	for k, v := range taskStyle {
+		result[k] = v
+	}
+	return result
+}