Make D&D prompt asset manifests exact

internal/modules/dnd/shared/assets.go

@@ -2,7 +2,9 @@ package shared
 
 import (
 	"embed"
+	"fmt"
 	"io/fs"
+	"strings"
 
 	"gitea.maximumdirect.net/eric/notarius/internal/framework/llm"
 	"gitea.maximumdirect.net/eric/notarius/internal/framework/promptfs"
@@ -11,39 +13,69 @@ import (
 //go:embed assets/prompts/*.md
 var embeddedAssets embed.FS
 
-var sharedPromptFiles = []string{
-	"common-dnd-system.md",
-	"common-dnd-transcript.md",
-	"common-dnd-references.md",
-	"common-dnd-npcs.md",
+// PromptAssetManifest is the ordered set of assets that make up one prompt.
+// Module files are addressed in the owning module filesystem; shared files use
+// the names in sharedPromptPaths and are mounted beneath sharedassets.
+type PromptAssetManifest struct {
+	ModuleDir   string
+	ModuleFiles []promptfs.ModulePromptFile
+	SharedFiles []string
 }
 
-func SharedPromptFiles() []promptfs.SharedPromptFile {
-	files := make([]promptfs.SharedPromptFile, 0, len(sharedPromptFiles))
-	for _, name := range sharedPromptFiles {
+var sharedPromptPaths = map[string]string{
+	"common-dnd-system.md":     "assets/prompts/common-dnd-system.md",
+	"common-dnd-transcript.md": "assets/prompts/common-dnd-transcript.md",
+	"common-dnd-references.md": "assets/prompts/common-dnd-references.md",
+	"common-dnd-npcs.md":       "assets/prompts/common-dnd-npcs.md",
+}
+
+func (manifest PromptAssetManifest) PromptFS(moduleFS fs.FS) (fs.FS, error) {
+	sharedFiles, err := resolveSharedPromptFiles(manifest.SharedFiles)
+	if err != nil {
+		return nil, err
+	}
+	moduleFiles := append([]promptfs.ModulePromptFile(nil), manifest.ModuleFiles...)
+	return promptfs.ModulePromptFS(manifest.ModuleDir, moduleFS, moduleFiles, sharedFiles...)
+}
+
+func (manifest PromptAssetManifest) Hash(moduleFS fs.FS) (string, error) {
+	sharedFiles, err := resolveSharedPromptFiles(manifest.SharedFiles)
+	if err != nil {
+		return "", err
+	}
+	parts := make([]llm.AssetHashPart, 0, len(manifest.ModuleFiles)+len(sharedFiles))
+	for _, file := range manifest.ModuleFiles {
+		parts = append(parts, llm.AssetHashPart{FS: moduleFS, Path: file.Path})
+	}
+	for _, file := range sharedFiles {
+		parts = append(parts, llm.AssetHashPart{FS: file.FS, Path: file.Path})
+	}
+	return llm.HashAssets(parts)
+}
+
+func resolveSharedPromptFiles(names []string) ([]promptfs.SharedPromptFile, error) {
+	files := make([]promptfs.SharedPromptFile, 0, len(names))
+	seen := make(map[string]struct{}, len(names))
+	for _, name := range names {
+		if name == "" {
+			return nil, fmt.Errorf("shared prompt asset name must not be empty")
+		}
+		if strings.ContainsAny(name, `/\\`) {
+			return nil, fmt.Errorf("shared prompt asset name %q must not contain path separators", name)
+		}
+		if _, ok := seen[name]; ok {
+			return nil, fmt.Errorf("duplicate shared prompt asset name %q", name)
+		}
+		path, ok := sharedPromptPaths[name]
+		if !ok {
+			return nil, fmt.Errorf("unknown shared prompt asset name %q", name)
+		}
+		seen[name] = struct{}{}
 		files = append(files, promptfs.SharedPromptFile{
 			Name: name,
 			FS:   embeddedAssets,
-			Path: "assets/prompts/" + name,
+			Path: path,
 		})
 	}
-	return files
-}
-
-func CommonHashParts() []llm.AssetHashPart {
-	return []llm.AssetHashPart{
-		{FS: embeddedAssets, Path: "assets/prompts/common-dnd-system.md"},
-		{FS: embeddedAssets, Path: "assets/prompts/common-dnd-transcript.md"},
-	}
-}
-
-func ReferenceHashParts() []llm.AssetHashPart {
-	return []llm.AssetHashPart{
-		{FS: embeddedAssets, Path: "assets/prompts/common-dnd-references.md"},
-		{FS: embeddedAssets, Path: "assets/prompts/common-dnd-npcs.md"},
-	}
-}
-
-func ModulePromptFS(moduleDir string, moduleFS fs.FS, files []promptfs.ModulePromptFile) (fs.FS, error) {
-	return promptfs.ModulePromptFS(moduleDir, moduleFS, files, SharedPromptFiles()...)
+	return files, nil
 }