feat(modules): port packages module to Go

internal/modules/packages/packages.go

@@ -0,0 +1,74 @@
+// Package packages installs a declarative list of pacman packages.
+package packages
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/MDietermann/ArduinoArchSetup/internal/module"
+	"github.com/MDietermann/ArduinoArchSetup/internal/platform"
+)
+
+type Module struct {
+	pkgs []string
+	pm   platform.PackageManager
+}
+
+func New(pkgs []string, pm platform.PackageManager) Module {
+	return Module{pkgs: pkgs, pm: pm}
+}
+
+type state struct{ Missing []string }
+
+func (Module) Meta() module.Meta {
+	return module.Meta{ID: "packages", Name: "Base packages", Description: "Install base pacman package list."}
+}
+
+func (m Module) Detect(ctx context.Context) (module.State, error) {
+	var missing []string
+	for _, p := range m.pkgs {
+		ok, err := m.pm.IsInstalled(ctx, p)
+		if err != nil {
+			return nil, err
+		}
+		if !ok {
+			missing = append(missing, p)
+		}
+	}
+	return state{Missing: missing}, nil
+}
+
+func (m Module) Plan(ctx context.Context, cur module.State) (module.Plan, error) {
+	s, _ := cur.(state)
+	if len(s.Missing) == 0 {
+		return module.Plan{}, nil
+	}
+	missing := append([]string{}, s.Missing...)
+	return module.Plan{Actions: []module.Action{{
+		Description: "pacman install " + strings.Join(missing, ", "),
+		Kind:        module.ActionPackageInstall,
+		Exec:        func(ctx context.Context) error { return m.pm.Install(ctx, missing) },
+	}}}, nil
+}
+
+func (m Module) Apply(ctx context.Context, p module.Plan, r module.Reporter) error {
+	for i, a := range p.Actions {
+		r.Progress(m.Meta().ID, i+1, len(p.Actions), a.Description)
+		if err := a.Exec(ctx); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (m Module) Verify(ctx context.Context) error {
+	st, err := m.Detect(ctx)
+	if err != nil {
+		return err
+	}
+	if missing := st.(state).Missing; len(missing) > 0 {
+		return fmt.Errorf("packages not installed after apply: %v", missing)
+	}
+	return nil
+}