Move engine composition into the internal engine package

internal/engine/engine.go

@@ -0,0 +1,145 @@
+// Package engine assembles Promptkit's internal execution components.
+package engine
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+
+	openrouter "gitea.maximumdirect.net/eric/promptkit-backend-openrouter"
+	rakestrawhome "gitea.maximumdirect.net/eric/promptkit-backend-rakestrawhome"
+	"gitea.maximumdirect.net/eric/promptkit/internal/artifact"
+	"gitea.maximumdirect.net/eric/promptkit/internal/backend"
+	"gitea.maximumdirect.net/eric/promptkit/internal/capacity"
+	"gitea.maximumdirect.net/eric/promptkit/internal/catalog"
+	"gitea.maximumdirect.net/eric/promptkit/internal/defaults"
+	"gitea.maximumdirect.net/eric/promptkit/internal/domain"
+	"gitea.maximumdirect.net/eric/promptkit/internal/llm"
+	"gitea.maximumdirect.net/eric/promptkit/internal/profile"
+	"gitea.maximumdirect.net/eric/promptkit/internal/prompt"
+	"gitea.maximumdirect.net/eric/promptkit/internal/promptdef"
+	"gitea.maximumdirect.net/eric/promptkit/internal/usecase"
+	"gitea.maximumdirect.net/eric/promptkit/internal/validate"
+)
+
+// Config carries construction settings selected by the public facade.
+type Config struct {
+	PromptDir  string
+	ProfileDir string
+	SchemaDir  string
+	Timeout    time.Duration
+	HTTPClient *http.Client
+}
+
+// Options carries collaborators prepared by the public facade during the
+// transitional composition split.
+type Options struct {
+	LLMClient             llm.Client
+	ArtifactReader        artifact.Reader
+	PromptDefinitions     promptdef.Repository
+	Profiles              profile.Repository
+	FallbackProfiles      profile.Repository
+	MemoryProfiles        profile.Repository
+	Backends              []domain.Backend
+	Validator             validate.Validator
+	PromptSource          bool
+	ProfileSource         bool
+	FallbackProfileSource bool
+	MemorySource          bool
+	ValidatorSource       bool
+	ArtifactSource        bool
+}
+
+// Engine forwards domain operations to the single assembled use-case runner.
+type Engine struct {
+	runner *usecase.Runner
+}
+
+// New assembles an engine from facade-selected configuration and collaborators.
+func New(cfg Config, options Options) (*Engine, error) {
+	promptDefinitions := options.PromptDefinitions
+	if !options.PromptSource {
+		if strings.TrimSpace(cfg.PromptDir) == "" {
+			return nil, fmt.Errorf("prompt directory is required")
+		}
+		promptDefinitions = promptdef.NewFilesystemRepository(cfg.PromptDir)
+	}
+
+	maintained, err := catalog.Load(
+		catalog.Source{Name: "OpenRouter", ExpectedBackendID: backend.OpenRouterID, FS: openrouter.FS(), Root: openrouter.Root},
+		catalog.Source{Name: "Rakestrawhome", ExpectedBackendID: backend.RakestrawHomeID, FS: rakestrawhome.FS(), Root: rakestrawhome.Root},
+	)
+	if err != nil {
+		return nil, fmt.Errorf("failed to load maintained catalogs: %w", err)
+	}
+
+	profiles := newProfileRepository(cfg.ProfileDir, options, maintained.Profiles)
+	registry, err := backend.NewRegistry(maintained.Backends, options.Backends)
+	if err != nil {
+		return nil, fmt.Errorf("failed to construct backend registry: %w", err)
+	}
+	manager, err := capacity.NewManager(registry.CapacityPolicies())
+	if err != nil {
+		return nil, fmt.Errorf("failed to construct backend capacity manager: %w", err)
+	}
+
+	validator := options.Validator
+	if !options.ValidatorSource {
+		schemaDir := cfg.SchemaDir
+		if strings.TrimSpace(schemaDir) == "" {
+			schemaDir = defaults.SchemaDirDefault
+		}
+		validator = validate.NewStandardValidator(schemaDir)
+	}
+	client := options.LLMClient
+	if client == nil {
+		client, err = llm.NewOpenAICompatibleClient(llm.OpenAICompatibleConfig{Timeout: cfg.Timeout, HTTPClient: cfg.HTTPClient})
+		if err != nil {
+			return nil, err
+		}
+	}
+	client = capacity.NewClient(manager, client)
+	reader := options.ArtifactReader
+	if !options.ArtifactSource {
+		reader = artifact.NewCompositeReader()
+	}
+
+	return &Engine{runner: usecase.NewRunnerWithRepairer(promptDefinitions, profiles, registry, reader, prompt.NewGoRenderer(), client, validator, usecase.NewDefaultOutputRepairer(client), manager)}, nil
+}
+
+func newProfileRepository(profileDir string, options Options, maintained profile.Repository) profile.Repository {
+	repository := maintained
+	if options.FallbackProfileSource {
+		repository = profile.NewOverlayRepository(options.FallbackProfiles, repository)
+	}
+	if options.ProfileSource {
+		repository = profile.NewOverlayRepository(options.Profiles, repository)
+	} else if strings.TrimSpace(profileDir) != "" {
+		repository = profile.NewOverlayRepository(profile.NewFilesystemRepository(profileDir), repository)
+	}
+	if options.MemorySource {
+		repository = profile.NewOverlayRepository(options.MemoryProfiles, repository)
+	}
+	return profile.NewResolvingRepository(repository)
+}
+
+func (e *Engine) InspectPrompt(ctx context.Context, id, version string) (*domain.PromptInspection, error) {
+	return e.runner.InspectPrompt(ctx, id, version)
+}
+func (e *Engine) InspectProfile(ctx context.Context, id string) (*domain.ProfileInspection, error) {
+	return e.runner.InspectProfile(ctx, id)
+}
+func (e *Engine) Prepare(ctx context.Context, request domain.RunRequest) (*domain.PreparedRun, error) {
+	return e.runner.Prepare(ctx, request)
+}
+func (e *Engine) PrepareExecution(ctx context.Context, request domain.RunRequest) (*usecase.PreparedExecution, error) {
+	return e.runner.PrepareExecution(ctx, request)
+}
+func (e *Engine) Run(ctx context.Context, request domain.RunRequest) (*domain.RunResult, error) {
+	return e.runner.Run(ctx, request)
+}
+func (e *Engine) RunPrepared(ctx context.Context, prepared *usecase.PreparedExecution) (*domain.RunResult, error) {
+	return e.runner.RunPrepared(ctx, prepared)
+}