feat(agent): 云端 Agent - 增加上下文预算、任务事实与终态恢复保障

backend/internal/app/cloud_agent_generation_contract.go

@@ -0,0 +1,70 @@
+package app
+
+import (
+	"infinite-canvas/backend/internal/canvas/contract"
+	"strings"
+)
+
+// Agent arguments and the canvas editor enter the same public generation codec.
+// Resource materialization and provider credentials remain outside this object.
+func cloudAgentGenerationSpec(a cloudAgentMediaArgs, refs map[string]any, resolvedConfig map[string]any) (contract.GenerationSpec, error) {
+	selection := &contract.ModelSelection{Kind: "channel", ChannelID: a.ChannelID, ModelKey: a.ChannelModelKey}
+	if a.LogicalModelID != "" {
+		selection = &contract.ModelSelection{Kind: "logical", LogicalModelID: a.LogicalModelID}
+	}
+	options := contract.Options{}
+	if a.Mode == "image" || a.Mode == "video" {
+		options.Size = &a.Size
+	}
+	if a.Mode == "video" {
+		options.DurationSeconds, options.GenerateAudio = &a.Duration, a.VideoGenerateAudio
+		if a.Quality != "" {
+			options.Resolution = &a.Quality
+		}
+	} else if a.Mode == "image" {
+		count := 1
+		options.Count = &count
+		if a.Quality != "" {
+			options.Quality = &a.Quality
+		}
+	}
+	if resolvedConfig != nil {
+		config := options.TaskConfig()
+		for key, value := range resolvedConfig {
+			config[key] = value
+		}
+		var err error
+		options, err = contract.OptionsFromTaskConfig(a.Mode, config)
+		if err != nil {
+			return contract.GenerationSpec{}, err
+		}
+	}
+	byID := map[string]contract.ReferenceBinding{}
+	for _, media := range []struct{ field, kind string }{{"referenceImages", "image"}, {"referenceVideos", "video"}, {"referenceAudios", "audio"}} {
+		for _, ref := range creationMaps(refs[media.field]) {
+			id := stringValue(ref["id"])
+			binding := contract.ReferenceBinding{ID: "node:" + id, NodeID: id, MediaType: media.kind, Role: "reference", Resolution: "latest"}
+			if key := stringValue(ref["storageKey"]); strings.HasPrefix(key, "resource:") {
+				binding.ResourceID = strings.TrimPrefix(key, "resource:")
+			}
+			byID[id] = binding
+		}
+	}
+	bindings := []contract.ReferenceBinding{}
+	for _, id := range a.ReferenceNodeIDs {
+		binding, exists := byID[id]
+		if !exists {
+			return contract.GenerationSpec{}, BadAuthRequest("生成引用未解析，不能保存不完整生成规格")
+		}
+		binding.Order = len(bindings)
+		bindings = append(bindings, binding)
+	}
+	for _, id := range a.ReferenceTransientIDs {
+		bindings = append(bindings, contract.ReferenceBinding{ID: "transient:" + id, TransientID: id, MediaType: "image", Role: "reference", Order: len(bindings), Resolution: "snapshot"})
+	}
+	if a.SourceNodeID != "" {
+		bindings = append(bindings, contract.ReferenceBinding{ID: "node:" + a.SourceNodeID, NodeID: a.SourceNodeID, MediaType: "text", Role: "source-text", Order: len(bindings), Resolution: "latest"})
+	}
+	spec := contract.GenerationSpec{Version: contract.GenerationVersion, Mode: a.Mode, Prompt: a.Prompt, ModelSelection: selection, Options: options, ReferenceBindings: bindings, TextInputMode: "prompt-only"}
+	return spec, spec.Validate()
+}