t7 centralize provider registries

2 files changed, 146 insertions, 0 deletions

diff --git a/internal/text/registry.go b/internal/text/registry.go
new file mode 100644
index 0000000..e337b16
--- /dev/null
+++ b/internal/text/registry.go
@@ -0,0 +1,80 @@
+package text
+
+import (
+	"fmt"
+	"reflect"
+
+	"codeberg.org/snonux/comicforge/internal/provider"
+)
+
+// Config exposes the configured text provider settings.
+type Config interface {
+	provider.TextConfig
+	GoogleAPIKey() string
+	TextModel() string
+}
+
+// Registry resolves provider names to factories.
+type Registry struct {
+	*provider.Registry[provider.TextProvider, Config]
+}
+
+// NewRegistry creates an empty text-provider registry.
+func NewRegistry() *Registry {
+	return &Registry{
+		Registry: provider.NewRegistry[provider.TextProvider, Config](),
+	}
+}
+
+// DefaultRegistry returns the built-in text provider registry.
+func DefaultRegistry() *Registry {
+	registry := NewRegistry()
+	registry.Register(provider.Gemini, func(cfg Config) (provider.TextProvider, error) {
+		geminiProvider := NewGeminiProvider(&GeminiConfig{
+			APIKey: cfg.GoogleAPIKey(),
+			Model:  cfg.TextModel(),
+		})
+		if err := geminiProvider.IsAvailable(); err != nil {
+			return nil, err
+		}
+		return geminiProvider, nil
+	})
+	registry.Register(provider.OpenAI, func(Config) (provider.TextProvider, error) {
+		return nil, fmt.Errorf("text provider %q is not implemented", provider.OpenAI)
+	})
+	return registry
+}
+
+// Has reports whether a factory is registered for name.
+func (r *Registry) Has(name string) bool {
+	if r == nil || r.Registry == nil {
+		return false
+	}
+	_, ok := r.Resolve(name)
+	return ok
+}
+
+// NewFromConfig resolves the provider name from cfg and constructs it.
+func (r *Registry) NewFromConfig(cfg Config) (provider.TextProvider, error) {
+	if r == nil || r.Registry == nil {
+		return nil, fmt.Errorf("text registry is required")
+	}
+	if isNilValue(cfg) {
+		return nil, fmt.Errorf("text config is required")
+	}
+	return r.New(cfg.TextProviderName(), cfg)
+}
+
+func isNilValue[T any](value T) bool {
+	v := reflect.ValueOf(value)
+	if !v.IsValid() {
+		return true
+	}
+
+	switch v.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Pointer, reflect.Slice:
+		return v.IsNil()
+	default:
+		return false
+	}
+}
diff --git a/internal/text/registry_test.go b/internal/text/registry_test.go
new file mode 100644
index 0000000..3f5f72a
--- /dev/null
+++ b/internal/text/registry_test.go
@@ -0,0 +1,66 @@
+package text
+
+import (
+	"errors"
+	"strings"
+	"testing"
+
+	"codeberg.org/snonux/comicforge/internal/provider"
+)
+
+func TestDefaultRegistryNewFromConfig(t *testing.T) {
+	t.Parallel()
+
+	registry := DefaultRegistry()
+	gotProvider, err := registry.NewFromConfig(fakeConfig{
+		name:   provider.Gemini,
+		apiKey: "test-key",
+		model:  "gemini-2.5-flash",
+	})
+	if err != nil {
+		t.Fatalf("NewFromConfig() error = %v", err)
+	}
+	if got, want := gotProvider.Name(), provider.Gemini; got != want {
+		t.Fatalf("provider.Name() = %q, want %q", got, want)
+	}
+}
+
+func TestDefaultRegistryUnsupportedProvider(t *testing.T) {
+	t.Parallel()
+
+	registry := DefaultRegistry()
+	_, err := registry.NewFromConfig(fakeConfig{
+		name:   provider.OpenAI,
+		apiKey: "test-key",
+		model:  "unused",
+	})
+	if err == nil {
+		t.Fatal("expected unsupported provider error")
+	}
+	if !strings.Contains(err.Error(), "text provider \"openai\" is not implemented") {
+		t.Fatalf("error = %v, want unsupported provider error", err)
+	}
+}
+
+func TestRegistryUnknownProvider(t *testing.T) {
+	t.Parallel()
+
+	registry := DefaultRegistry()
+	_, err := registry.New("missing", fakeConfig{})
+	if err == nil {
+		t.Fatal("expected unknown provider error")
+	}
+	if !errors.Is(err, provider.ErrUnknownProvider) {
+		t.Fatalf("error = %v, want ErrUnknownProvider", err)
+	}
+}
+
+type fakeConfig struct {
+	name   string
+	apiKey string
+	model  string
+}
+
+func (f fakeConfig) TextProviderName() string { return f.name }
+func (f fakeConfig) GoogleAPIKey() string     { return f.apiKey }
+func (f fakeConfig) TextModel() string        { return f.model }