feat(modules): port themes module to Go

internal/modules/themes/themes.go

@@ -0,0 +1,115 @@
+// Package themes installs archduino theme files into ~/.config/archduino/themes.
+package themes
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io/fs"
+	"os"
+	"path/filepath"
+
+	"github.com/MDietermann/ArduinoArchSetup/internal/config"
+	"github.com/MDietermann/ArduinoArchSetup/internal/module"
+)
+
+type Module struct{ cfg config.ThemesConfig }
+
+func New(cfg config.ThemesConfig) Module { return Module{cfg: cfg} }
+
+type filePair struct{ src, dst string }
+type state struct{ Missing []filePair }
+
+func (Module) Meta() module.Meta {
+	return module.Meta{ID: "themes", Name: "Colorscheme themes", Description: "Install archduino themes."}
+}
+
+func destRoot() (string, error) {
+	h, err := os.UserHomeDir()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(h, ".config", "archduino", "themes"), nil
+}
+
+func (m Module) Detect(ctx context.Context) (module.State, error) {
+	dst, err := destRoot()
+	if err != nil {
+		return nil, err
+	}
+	var missing []filePair
+	err = filepath.WalkDir(m.cfg.Source, func(p string, d fs.DirEntry, werr error) error {
+		if werr != nil {
+			return werr
+		}
+		if d.IsDir() {
+			return nil
+		}
+		rel, _ := filepath.Rel(m.cfg.Source, p)
+		target := filepath.Join(dst, rel)
+		a, errA := os.ReadFile(p)
+		if errA != nil {
+			return errA
+		}
+		b, errB := os.ReadFile(target)
+		if errB != nil || !bytes.Equal(a, b) {
+			missing = append(missing, filePair{src: p, dst: target})
+		}
+		return nil
+	})
+	if err != nil {
+		if os.IsNotExist(err) {
+			return state{}, nil
+		}
+		return nil, err
+	}
+	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
+	}
+	pairs := append([]filePair{}, s.Missing...)
+	return module.Plan{Actions: []module.Action{{
+		Description: fmt.Sprintf("copy %d theme files", len(pairs)),
+		Kind:        module.ActionFileWrite,
+		Exec: func(ctx context.Context) error {
+			for _, fp := range pairs {
+				if err := os.MkdirAll(filepath.Dir(fp.dst), 0o755); err != nil {
+					return err
+				}
+				data, err := os.ReadFile(fp.src)
+				if err != nil {
+					return err
+				}
+				if err := os.WriteFile(fp.dst, data, 0o644); err != nil {
+					return err
+				}
+			}
+			return nil
+		},
+	}}}, 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 miss := st.(state).Missing; len(miss) > 0 {
+		return fmt.Errorf("themes still missing: %d files", len(miss))
+	}
+	return nil
+}