feat: Настройки › Автообновление - clients compare their version with the server's every N and update themselves; the server looks at GitLab every N and, when a newer release is out, offers it to an administrator at login (after the PIN) with «Обновить» and «Отказаться»; the words of a made picture's result are the model's only

internal/proto/version.go

@@ -0,0 +1,50 @@
+package proto
+
+import (
+	"strconv"
+	"strings"
+)
+
+// versionParts reads "0.2.5" (a leading v and a "-suffix" are allowed) as
+// numbers; ok is false for anything that is not a dotted number.
+func versionParts(v string) (parts []int, ok bool) {
+	v = strings.TrimPrefix(strings.TrimSpace(v), "v")
+	if i := strings.IndexAny(v, "-+"); i >= 0 {
+		v = v[:i]
+	}
+	if v == "" {
+		return nil, false
+	}
+	for _, p := range strings.Split(v, ".") {
+		n, err := strconv.Atoi(p)
+		if err != nil || n < 0 {
+			return nil, false
+		}
+		parts = append(parts, n)
+	}
+	return parts, true
+}
+
+// VersionNewer reports whether version a is higher than b. Anything that is
+// not a dotted number (a build named "dev", an empty string) is never newer
+// and never older - so a program is never "updated" down, or from a guess.
+func VersionNewer(a, b string) bool {
+	pa, okA := versionParts(a)
+	pb, okB := versionParts(b)
+	if !okA || !okB {
+		return false
+	}
+	for i := 0; i < len(pa) || i < len(pb); i++ {
+		var x, y int
+		if i < len(pa) {
+			x = pa[i]
+		}
+		if i < len(pb) {
+			y = pb[i]
+		}
+		if x != y {
+			return x > y
+		}
+	}
+	return false
+}