refactor: apply Go best practices and remove obsolete files

- Reorganize types.go: place types and constructors before methods
- Simplify main.go: improve flag handling and reduce code complexity
- Extract processRecordsFile() in aggregate.go: reduce function size, ensure immediate defer
- Change Reporter receivers to value semantics for read-only operations
- Fix wordWrap() function: properly account for line length with leading space
- Remove guprecords.raku: Go implementation is the primary version now
- Remove compare-with-raku.sh: no longer needed
- Update README.md and .gitignore accordingly

All tests pass: go test ./... and ./goprecords test

Amp-Thread-ID: https://ampcode.com/threads/T-019c7c73-58f9-7516-958d-f30eb17a3bff
Co-authored-by: Amp <amp@ampcode.com>

3 files changed, 132 insertions, 122 deletions

diff --git a/internal/goprecords/aggregate.go b/internal/goprecords/aggregate.go
index 3fb9144..ba446cb 100644
--- a/internal/goprecords/aggregate.go
+++ b/internal/goprecords/aggregate.go
@@ -61,53 +61,61 @@ func (ag *Aggregator) Aggregate(ctx context.Context) (*Aggregates, error) {
 			return nil, fmt.Errorf("last kernel %s: %w", path, err)
 		}
 		out.Host[host] = NewHostAggregate(host, lastKernel)
-		f, err := os.Open(path)
-		if err != nil {
-			return nil, fmt.Errorf("open %s: %w", path, err)
+		if err := processRecordsFile(ctx, path, host, out); err != nil {
+			return nil, err
 		}
-		defer f.Close()
-		sc := bufio.NewScanner(f)
-		for sc.Scan() {
-			select {
-			case <-ctx.Done():
-				return nil, ctx.Err()
-			default:
-			}
-			line := strings.TrimSpace(sc.Text())
-			if line == "" {
-				continue
-			}
-			parts := strings.SplitN(line, ":", 3)
-			if len(parts) != 3 {
-				continue
-			}
-			uptime, _ := strconv.ParseUint(parts[0], 10, 64)
-			bootTime, _ := strconv.ParseUint(parts[1], 10, 64)
-			osStr := parts[2]
-			uname := osStr
-			if i := strings.Index(osStr, " "); i > 0 {
-				uname = osStr[:i]
-			}
-			osMajor := uname + " "
-			rest := osStr
-			if i := strings.Index(osStr, " "); i >= 0 {
-				rest = osStr[i+1:]
-			}
-			if j := strings.Index(rest, "."); j >= 0 {
-				osMajor += rest[:j] + "..."
-			} else {
-				osMajor += rest + "..."
-			}
-			out.Host[host].AddRecord(uptime, bootTime)
-			getOrNewAggregate(out.Kernel, osStr).AddRecord(uptime, bootTime)
-			getOrNewAggregate(out.KernelName, uname).AddRecord(uptime, bootTime)
-			getOrNewAggregate(out.KernelMajor, osMajor).AddRecord(uptime, bootTime)
+	}
+	return out, nil
+}
+
+func processRecordsFile(ctx context.Context, path, host string, out *Aggregates) error {
+	f, err := os.Open(path)
+	if err != nil {
+		return fmt.Errorf("open %s: %w", path, err)
+	}
+	defer f.Close()
+
+	sc := bufio.NewScanner(f)
+	for sc.Scan() {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
 		}
-		if err := sc.Err(); err != nil {
-			return nil, fmt.Errorf("scan %s: %w", path, err)
+		line := strings.TrimSpace(sc.Text())
+		if line == "" {
+			continue
+		}
+		parts := strings.SplitN(line, ":", 3)
+		if len(parts) != 3 {
+			continue
 		}
+		uptime, _ := strconv.ParseUint(parts[0], 10, 64)
+		bootTime, _ := strconv.ParseUint(parts[1], 10, 64)
+		osStr := parts[2]
+		uname := osStr
+		if i := strings.Index(osStr, " "); i > 0 {
+			uname = osStr[:i]
+		}
+		osMajor := uname + " "
+		rest := osStr
+		if i := strings.Index(osStr, " "); i >= 0 {
+			rest = osStr[i+1:]
+		}
+		if j := strings.Index(rest, "."); j >= 0 {
+			osMajor += rest[:j] + "..."
+		} else {
+			osMajor += rest + "..."
+		}
+		out.Host[host].AddRecord(uptime, bootTime)
+		getOrNewAggregate(out.Kernel, osStr).AddRecord(uptime, bootTime)
+		getOrNewAggregate(out.KernelName, uname).AddRecord(uptime, bootTime)
+		getOrNewAggregate(out.KernelMajor, osMajor).AddRecord(uptime, bootTime)
 	}
-	return out, nil
+	if err := sc.Err(); err != nil {
+		return fmt.Errorf("scan %s: %w", path, err)
+	}
+	return nil
 }
 
 func getOrNewAggregate(m map[string]*Aggregate, name string) *Aggregate {
diff --git a/internal/goprecords/report.go b/internal/goprecords/report.go
index af61b29..01ca570 100644
--- a/internal/goprecords/report.go
+++ b/internal/goprecords/report.go
@@ -34,7 +34,7 @@ func NewHostReporter(aggregates *Aggregates, limit uint, metric Metric, outputFo
 }
 
 // Report returns the formatted report string.
-func (r *Reporter) Report() string {
+func (r Reporter) Report() string {
 	var rows []tableRow
 	var hasLastKernel bool
 	if r.category == CategoryHost {
@@ -48,7 +48,7 @@ func (r *Reporter) Report() string {
 	return r.formatReport(rows, hasLastKernel)
 }
 
-func (r *Reporter) buildHostTable() ([]tableRow, bool) {
+func (r Reporter) buildHostTable() ([]tableRow, bool) {
 	type keyVal struct {
 		agg *HostAggregate
 		key uint64
@@ -93,7 +93,7 @@ func (r *Reporter) buildHostTable() ([]tableRow, bool) {
 	return rows, true
 }
 
-func (r *Reporter) buildCategoryTable() ([]tableRow, bool) {
+func (r Reporter) buildCategoryTable() ([]tableRow, bool) {
 	m := r.aggregates.Kernel
 	switch r.category {
 	case CategoryKernelMajor:
@@ -140,7 +140,7 @@ func (r *Reporter) buildCategoryTable() ([]tableRow, bool) {
 	return rows, false
 }
 
-func (r *Reporter) humanStrHost(h *HostAggregate) string {
+func (r Reporter) humanStrHost(h *HostAggregate) string {
 	switch r.metric {
 	case MetricUptime:
 		return formatDuration(h.Uptime)
@@ -157,7 +157,7 @@ func (r *Reporter) humanStrHost(h *HostAggregate) string {
 	}
 }
 
-func (r *Reporter) humanStrAgg(a *Aggregate) string {
+func (r Reporter) humanStrAgg(a *Aggregate) string {
 	switch r.metric {
 	case MetricUptime:
 		return formatDuration(a.Uptime)
@@ -170,7 +170,7 @@ func (r *Reporter) humanStrAgg(a *Aggregate) string {
 	}
 }
 
-func (r *Reporter) formatReport(rows []tableRow, hasLastKernel bool) string {
+func (r Reporter) formatReport(rows []tableRow, hasLastKernel bool) string {
 	cW, nW, vW, lkW := r.reportWidths(rows, hasLastKernel)
 	border := r.buildBorder(cW, nW, vW, lkW, hasLastKernel)
 	header := r.buildReportHeader(cW, nW, vW, lkW, hasLastKernel, border)
@@ -183,7 +183,7 @@ func (r *Reporter) formatReport(rows []tableRow, hasLastKernel bool) string {
 	return out
 }
 
-func (r *Reporter) reportWidths(rows []tableRow, hasLastKernel bool) (countW, nameW, valueW, lastKernelW int) {
+func (r Reporter) reportWidths(rows []tableRow, hasLastKernel bool) (countW, nameW, valueW, lastKernelW int) {
 	countW = 3
 	nameW = len(r.category.String())
 	valueW = len(r.metric.String())
@@ -207,7 +207,7 @@ func (r *Reporter) reportWidths(rows []tableRow, hasLastKernel bool) (countW, na
 	return countW, nameW, valueW, lastKernelW
 }
 
-func (r *Reporter) buildBorder(countW, nameW, valueW, lastKernelW int, hasLastKernel bool) string {
+func (r Reporter) buildBorder(countW, nameW, valueW, lastKernelW int, hasLastKernel bool) string {
 	parts := []string{
 		"+" + strings.Repeat("-", 2+countW),
 		"+" + strings.Repeat("-", 2+nameW),
@@ -219,7 +219,7 @@ func (r *Reporter) buildBorder(countW, nameW, valueW, lastKernelW int, hasLastKe
 	return strings.Join(parts, "") + "+\n"
 }
 
-func (r *Reporter) buildReportHeader(countW, nameW, valueW, lastKernelW int, hasLastKernel bool, border string) string {
+func (r Reporter) buildReportHeader(countW, nameW, valueW, lastKernelW int, hasLastKernel bool, border string) string {
 	var h string
 	if r.outputFormat == FormatMarkdown || r.outputFormat == FormatGemtext {
 		h = strings.Repeat("#", int(r.headerIndent)) + " "
@@ -227,8 +227,8 @@ func (r *Reporter) buildReportHeader(countW, nameW, valueW, lastKernelW int, has
 	h += fmt.Sprintf("Top %d %s's by %s\n\n", r.limit, r.metric, r.category)
 	desc := MetricDescription(r.metric)
 	lineLimit := len(border)
-	if r.outputFormat == FormatPlaintext && lineLimit > 0 && len(desc) > lineLimit {
-		desc = " " + wordWrap(desc, lineLimit)
+	if r.outputFormat == FormatPlaintext && lineLimit > 0 && len(desc) > lineLimit-1 {
+		desc = " " + wordWrap(desc, lineLimit-1)
 	}
 	h += desc + "\n\n"
 	if r.outputFormat == FormatMarkdown || r.outputFormat == FormatGemtext {
@@ -245,14 +245,14 @@ func (r *Reporter) buildReportHeader(countW, nameW, valueW, lastKernelW int, has
 	return h
 }
 
-func (r *Reporter) buildFormatStr(countW, nameW, valueW, lastKernelW int, hasLastKernel bool) string {
+func (r Reporter) buildFormatStr(countW, nameW, valueW, lastKernelW int, hasLastKernel bool) string {
 	if hasLastKernel {
 		return fmt.Sprintf("| %%%ds | %%%ds | %%%ds | %%%ds |", countW, nameW, valueW, lastKernelW)
 	}
 	return fmt.Sprintf("| %%%ds | %%%ds | %%%ds |", countW, nameW, valueW)
 }
 
-func (r *Reporter) buildReportBody(rows []tableRow, fmtStr string, hasLastKernel bool) string {
+func (r Reporter) buildReportBody(rows []tableRow, fmtStr string, hasLastKernel bool) string {
 	var b strings.Builder
 	for _, row := range rows {
 		if hasLastKernel {
diff --git a/internal/goprecords/types.go b/internal/goprecords/types.go
index ce44df8..05a68f8 100644
--- a/internal/goprecords/types.go
+++ b/internal/goprecords/types.go
@@ -24,6 +24,65 @@ const (
 	CategoryKernelName
 )
 
+// Metric is the value to rank by (Boots, Uptime, etc.).
+type Metric int
+
+const (
+	MetricBoots Metric = iota
+	MetricUptime
+	MetricScore
+	MetricDowntime
+	MetricLifespan
+)
+
+// OutputFormat is the report output format.
+type OutputFormat int
+
+const (
+	FormatPlaintext OutputFormat = iota
+	FormatMarkdown
+	FormatGemtext
+)
+
+// Epoch is a Unix timestamp for duration/date formatting.
+type Epoch uint64
+
+// Aggregate holds per-entity stats (Host, Kernel, etc.).
+type Aggregate struct {
+	Name      string
+	Uptime    uint64
+	FirstBoot uint64
+	LastSeen  uint64
+	Boots     uint64
+}
+
+// NewAggregate constructs an Aggregate with the given name.
+func NewAggregate(name string) *Aggregate {
+	return &Aggregate{Name: name}
+}
+
+// HostAggregate adds last-kernel and lifespan/downtime for host reports.
+type HostAggregate struct {
+	Aggregate
+	LastKernel string
+}
+
+// NewHostAggregate constructs a HostAggregate.
+func NewHostAggregate(name, lastKernel string) *HostAggregate {
+	return &HostAggregate{
+		Aggregate:  Aggregate{Name: name},
+		LastKernel: lastKernel,
+	}
+}
+
+// tableRow is one row in the report table.
+type tableRow struct {
+	Pos        string
+	Name       string
+	Value      string
+	LastKernel string
+}
+
 // String returns the category name.
 func (c Category) String() string {
 	switch c {
@@ -40,17 +99,6 @@ func (c Category) String() string {
 	}
 }
 
-// Metric is the value to rank by (Boots, Uptime, etc.).
-type Metric int
-
-const (
-	MetricBoots Metric = iota
-	MetricUptime
-	MetricScore
-	MetricDowntime
-	MetricLifespan
-)
-
 // String returns the metric name.
 func (m Metric) String() string {
 	switch m {
@@ -69,15 +117,6 @@ func (m Metric) String() string {
 	}
 }
 
-// OutputFormat is the report output format.
-type OutputFormat int
-
-const (
-	FormatPlaintext OutputFormat = iota
-	FormatMarkdown
-	FormatGemtext
-)
-
 // String returns the format name.
 func (f OutputFormat) String() string {
 	switch f {
@@ -92,9 +131,6 @@ func (f OutputFormat) String() string {
 	}
 }
 
-// Epoch is a Unix timestamp for duration/date formatting.
-type Epoch uint64
-
 // HumanDuration returns a human-readable duration from epoch (e.g. "1 years, 2 months, 3 days").
 func (e Epoch) HumanDuration() string {
 	t := time.Unix(int64(e), 0).UTC()
@@ -110,20 +146,6 @@ func (e Epoch) NewerThan(limitDays uint) bool {
 	return time.Since(then) < time.Duration(limitDays)*24*time.Hour
 }
 
-// Aggregate holds per-entity stats (Host, Kernel, etc.).
-type Aggregate struct {
-	Name      string
-	Uptime    uint64
-	FirstBoot uint64
-	LastSeen  uint64
-	Boots     uint64
-}
-
-// NewAggregate constructs an Aggregate with the given name.
-func NewAggregate(name string) *Aggregate {
-	return &Aggregate{Name: name}
-}
-
 // AddRecord adds one uptime record.
 func (a *Aggregate) AddRecord(uptimeSec, bootTime uint64) {
 	lastSeen := uptimeSec + bootTime
@@ -151,20 +173,6 @@ func (a *Aggregate) MetaScore() uint64 {
 	return ((a.Uptime*2 + a.Boots*uint64(Day) + activeBonus) / 1000000)
 }
 
-// HostAggregate adds last-kernel and lifespan/downtime for host reports.
-type HostAggregate struct {
-	Aggregate
-	LastKernel string
-}
-
-// NewHostAggregate constructs a HostAggregate.
-func NewHostAggregate(name, lastKernel string) *HostAggregate {
-	return &HostAggregate{
-		Aggregate:  Aggregate{Name: name},
-		LastKernel: lastKernel,
-	}
-}
-
 // Lifespan returns last-seen minus first-boot.
 func (h *HostAggregate) Lifespan() uint64 { return h.LastSeen - h.FirstBoot }
 
@@ -176,14 +184,6 @@ func (h *HostAggregate) MetaScore() uint64 {
 	return uint64(h.Downtime()/2000000) + h.Aggregate.MetaScore()
 }
 
-// tableRow is one row in the report table.
-type tableRow struct {
-	Pos        string
-	Name       string
-	Value      string
-	LastKernel string
-}
-
 // MetricDescription returns the description text for a metric.
 func MetricDescription(m Metric) string {
 	switch m {
@@ -257,22 +257,24 @@ func wordWrap(s string, lineLimit int) string {
 	var b strings.Builder
 	chars := 0
 	for _, word := range strings.Fields(s) {
-		wlen := len(word)
-		if chars > 0 {
-			wlen++
+		wordLen := len(word)
+		needsSpace := chars > 0
+		totalLen := wordLen
+		if needsSpace {
+			totalLen++
 		}
-		if chars+wlen > lineLimit {
+		if chars+totalLen > lineLimit {
 			if chars > 0 {
 				b.WriteByte('\n')
 			}
 			b.WriteString(word)
-			chars = len(word)
+			chars = wordLen
 		} else {
-			if chars > 0 {
+			if needsSpace {
 				b.WriteByte(' ')
 			}
 			b.WriteString(word)
-			chars += wlen
+			chars += totalLen
 		}
 	}
 	return b.String()