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")
+	}
+}

internal/inject/inject_test.go

@@ -0,0 +1,102 @@
+package inject
+
+import (
+	"context"
+	"errors"
+	"testing"
+)
+
+type fakeClipboard struct {
+	called bool
+	err    error
+}
+
+func (f *fakeClipboard) WriteClipboard(ctx context.Context, text string) error {
+	f.called = true
+	return f.err
+}
+
+type fakePaster struct {
+	called bool
+	err    error
+}
+
+func (f *fakePaster) Paste(ctx context.Context) error {
+	f.called = true
+	return f.err
+}
+
+type fakeTyper struct {
+	called bool
+	err    error
+}
+
+func (f *fakeTyper) TypeText(ctx context.Context, text string) error {
+	f.called = true
+	return f.err
+}
+
+func TestClipboardBackend(t *testing.T) {
+	cb := &fakeClipboard{}
+	p := &fakePaster{}
+	b := ClipboardBackend{Writer: cb, Paster: p}
+
+	err := b.Inject(context.Background(), "hello")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !cb.called || !p.called {
+		t.Fatalf("expected clipboard and paster to be called")
+	}
+}
+
+func TestClipboardBackendClipboardError(t *testing.T) {
+	cb := &fakeClipboard{err: errors.New("boom")}
+	p := &fakePaster{}
+	b := ClipboardBackend{Writer: cb, Paster: p}
+
+	err := b.Inject(context.Background(), "hello")
+	if err == nil {
+		t.Fatalf("expected error")
+	}
+	if !cb.called {
+		t.Fatalf("expected clipboard to be called")
+	}
+	if p.called {
+		t.Fatalf("did not expect paster to be called")
+	}
+}
+
+func TestInjectionBackend(t *testing.T) {
+	typ := &fakeTyper{}
+	b := InjectionBackend{Typer: typ}
+
+	err := b.Inject(context.Background(), "hello")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !typ.called {
+		t.Fatalf("expected typer to be called")
+	}
+}
+
+func TestNewBackend(t *testing.T) {
+	cb := &fakeClipboard{}
+	p := &fakePaster{}
+	typ := &fakeTyper{}
+
+	b, err := NewBackend("clipboard", Deps{Clipboard: cb, Paster: p, Typer: typ})
+	if err != nil || b == nil {
+		t.Fatalf("expected clipboard backend")
+	}
+
+	b, err = NewBackend("injection", Deps{Clipboard: cb, Paster: p, Typer: typ})
+	if err != nil || b == nil {
+		t.Fatalf("expected injection backend")
+	}
+
+	b, err = NewBackend("unknown", Deps{Clipboard: cb, Paster: p, Typer: typ})
+	if err == nil || b != nil {
+		t.Fatalf("expected error for unknown backend")
+	}
+}

internal/inject/xdotool.go

@@ -0,0 +1,63 @@
+package inject
+
+import (
+	"context"
+	"errors"
+	"os/exec"
+	"strings"
+)
+
+type Runner func(ctx context.Context, name string, args ...string) ([]byte, error)
+
+func DefaultRunner(ctx context.Context, name string, args ...string) ([]byte, error) {
+	cmd := exec.CommandContext(ctx, name, args...)
+	return cmd.CombinedOutput()
+}
+
+type XdotoolPaster struct {
+	Run Runner
+}
+
+func NewXdotoolPaster(run Runner) XdotoolPaster {
+	if run == nil {
+		run = DefaultRunner
+	}
+	return XdotoolPaster{Run: run}
+}
+
+func (p XdotoolPaster) Paste(ctx context.Context) error {
+	out, err := p.Run(ctx, "xdotool", "key", "--clearmodifiers", "ctrl+v")
+	if err != nil {
+		return formatRunError(out, err)
+	}
+	return nil
+}
+
+type XdotoolTyper struct {
+	Run Runner
+}
+
+func NewXdotoolTyper(run Runner) XdotoolTyper {
+	if run == nil {
+		run = DefaultRunner
+	}
+	return XdotoolTyper{Run: run}
+}
+
+func (t XdotoolTyper) TypeText(ctx context.Context, text string) error {
+	if strings.TrimSpace(text) == "" {
+		return errors.New("empty transcript")
+	}
+	out, err := t.Run(ctx, "xdotool", "type", "--clearmodifiers", "--delay", "1", text)
+	if err != nil {
+		return formatRunError(out, err)
+	}
+	return nil
+}
+
+func formatRunError(out []byte, err error) error {
+	if len(out) > 0 {
+		return errors.New(strings.TrimSpace(string(out)))
+	}
+	return err
+}