initial rebuild

internal/funcs/funcs.go

@@ -0,0 +1,209 @@
+package funcs
+
+import (
+	"bytes"
+	"fmt"
+	"html/template"
+	"math"
+	"net/url"
+	"strconv"
+	"strings"
+	"time"
+	"unicode"
+
+	"golang.org/x/text/language"
+	"golang.org/x/text/message"
+)
+
+var printer = message.NewPrinter(language.English)
+
+var TemplateFuncs = template.FuncMap{
+	// Time functions
+	"now":            time.Now,
+	"timeSince":      time.Since,
+	"timeUntil":      time.Until,
+	"formatTime":     formatTime,
+	"approxDuration": approxDuration,
+
+	// String functions
+	"uppercase": strings.ToUpper,
+	"lowercase": strings.ToLower,
+	"pluralize": pluralize,
+	"slugify":   slugify,
+	"safeHTML":  safeHTML,
+
+	// Slice functions
+	"join": strings.Join,
+
+	// Number functions
+	"incr":        incr,
+	"decr":        decr,
+	"formatInt":   formatInt,
+	"formatFloat": formatFloat,
+
+	// Boolean functions
+	"yesno": yesno,
+
+	// URL functions
+	"urlSetParam": urlSetParam,
+	"urlDelParam": urlDelParam,
+}
+
+func formatTime(format string, t time.Time) string {
+	return t.Format(format)
+}
+
+func approxDuration(d time.Duration) string {
+	const (
+		day  = 24 * time.Hour
+		year = 365 * day
+	)
+
+	formatUnit := func(count int, singular, plural string) string {
+		if count == 1 {
+			return fmt.Sprintf("1 %s", singular)
+		}
+		return fmt.Sprintf("%d %s", count, plural)
+	}
+
+	switch {
+	case d >= year:
+		return formatUnit(int(math.Round(float64(d)/float64(year))), "year", "years")
+	case d >= day:
+		return formatUnit(int(math.Round(float64(d)/float64(day))), "day", "days")
+	case d >= time.Hour:
+		return formatUnit(int(math.Round(d.Hours())), "hour", "hours")
+	case d >= time.Minute:
+		return formatUnit(int(math.Round(d.Minutes())), "minute", "minutes")
+	case d >= time.Second:
+		return formatUnit(int(math.Round(d.Seconds())), "second", "seconds")
+	default:
+		return "less than 1 second"
+	}
+}
+
+func pluralize(count any, singular string, plural string) (string, error) {
+	n, err := toInt64(count)
+	if err != nil {
+		return "", err
+	}
+
+	if n == 1 {
+		return singular, nil
+	}
+
+	return plural, nil
+}
+
+func slugify(s string) string {
+	var buf bytes.Buffer
+
+	for _, r := range s {
+		switch {
+		case r > unicode.MaxASCII:
+			continue
+		case unicode.IsLetter(r):
+			buf.WriteRune(unicode.ToLower(r))
+		case unicode.IsDigit(r), r == '_', r == '-':
+			buf.WriteRune(r)
+		case unicode.IsSpace(r):
+			buf.WriteRune('-')
+		}
+	}
+
+	return buf.String()
+}
+
+func safeHTML(s string) template.HTML {
+	return template.HTML(s)
+}
+
+func incr(i any) (int64, error) {
+	n, err := toInt64(i)
+	if err != nil {
+		return 0, err
+	}
+
+	n++
+	return n, nil
+}
+
+func decr(i any) (int64, error) {
+	n, err := toInt64(i)
+	if err != nil {
+		return 0, err
+	}
+
+	n--
+	return n, nil
+}
+
+func formatInt(i any) (string, error) {
+	n, err := toInt64(i)
+	if err != nil {
+		return "", err
+	}
+
+	return printer.Sprintf("%d", n), nil
+}
+
+func formatFloat(f float64, dp int) string {
+	format := "%." + strconv.Itoa(dp) + "f"
+	return printer.Sprintf(format, f)
+}
+
+func yesno(b bool) string {
+	if b {
+		return "Yes"
+	}
+
+	return "No"
+}
+
+func urlSetParam(u *url.URL, key string, value any) *url.URL {
+	nu := *u
+	values := nu.Query()
+
+	values.Set(key, fmt.Sprintf("%v", value))
+
+	nu.RawQuery = values.Encode()
+	return &nu
+}
+
+func urlDelParam(u *url.URL, key string) *url.URL {
+	nu := *u
+	values := nu.Query()
+
+	values.Del(key)
+
+	nu.RawQuery = values.Encode()
+	return &nu
+}
+
+func toInt64(i any) (int64, error) {
+	switch v := i.(type) {
+	case int:
+		return int64(v), nil
+	case int8:
+		return int64(v), nil
+	case int16:
+		return int64(v), nil
+	case int32:
+		return int64(v), nil
+	case int64:
+		return v, nil
+	case uint:
+		return int64(v), nil
+	case uint8:
+		return int64(v), nil
+	case uint16:
+		return int64(v), nil
+	case uint32:
+		return int64(v), nil
+	// Note: uint64 not supported due to risk of truncation.
+	case string:
+		return strconv.ParseInt(v, 10, 64)
+	}
+
+	return 0, fmt.Errorf("unable to convert type %T to int", i)
+}