Add injection backends

internal/inject/inject.go

@@ -0,0 +1,72 @@
+package inject
+
+import (
+	"context"
+	"errors"
+	"strings"
+)
+
+type Backend interface {
+	Inject(ctx context.Context, text string) error
+}
+
+type ClipboardWriter interface {
+	WriteClipboard(ctx context.Context, text string) error
+}
+
+type ClipboardWriterFunc func(ctx context.Context, text string) error
+
+func (f ClipboardWriterFunc) WriteClipboard(ctx context.Context, text string) error {
+	return f(ctx, text)
+}
+
+type Paster interface {
+	Paste(ctx context.Context) error
+}
+
+type Typer interface {
+	TypeText(ctx context.Context, text string) error
+}
+
+type Deps struct {
+	Clipboard ClipboardWriter
+	Paster    Paster
+	Typer     Typer
+}
+
+type ClipboardBackend struct {
+	Writer ClipboardWriter
+	Paster Paster
+}
+
+func (b ClipboardBackend) Inject(ctx context.Context, text string) error {
+	if b.Writer == nil || b.Paster == nil {
+		return errors.New("clipboard backend missing dependencies")
+	}
+	if err := b.Writer.WriteClipboard(ctx, text); err != nil {
+		return err
+	}
+	return b.Paster.Paste(ctx)
+}
+
+type InjectionBackend struct {
+	Typer Typer
+}
+
+func (b InjectionBackend) Inject(ctx context.Context, text string) error {
+	if b.Typer == nil {
+		return errors.New("injection backend missing dependencies")
+	}
+	return b.Typer.TypeText(ctx, text)
+}
+
+func NewBackend(name string, deps Deps) (Backend, error) {
+	switch strings.ToLower(strings.TrimSpace(name)) {
+	case "", "clipboard":
+		return ClipboardBackend{Writer: deps.Clipboard, Paster: deps.Paster}, nil
+	case "injection":
+		return InjectionBackend{Typer: deps.Typer}, nil
+	default:
+		return nil, errors.New("unknown injection backend")
+	}
+}