feat: 添加 utils 包及相关功能，包括 UA 解析和 IP 信息获取

pkg/utils/ua.go

@@ -0,0 +1,61 @@
+package utils
+
+import "regexp"
+
+type Result struct {
+  OS         string
+  OSVersion  string
+  Browser    string
+  BrowserVer string
+}
+
+// ParseUA 解析 UA，返回结构化信息
+func ParseUA(ua string) Result {
+  r := Result{}
+
+  // 1. 操作系统 + 版本
+  osRe := []*regexp.Regexp{
+    regexp.MustCompile(`\(Macintosh;.*Mac OS X ([0-9_]+)\)`),
+    regexp.MustCompile(`\(Windows NT ([0-9.]+)\)`),
+    regexp.MustCompile(`\(iPhone;.*OS ([0-9_]+)`),
+    regexp.MustCompile(`\(Android ([0-9.]+)`),
+    regexp.MustCompile(`\(X11;.*Linux `),
+  }
+  for _, re := range osRe {
+    if m := re.FindStringSubmatch(ua); len(m) > 1 {
+      switch {
+      case strings.Contains(m[0], "Macintosh"):
+        r.OS, r.OSVersion = "macOS", strings.Replace(m[1], "_", ".", -1)
+      case strings.Contains(m[0], "Windows NT"):
+        r.OS, r.OSVersion = "Windows", m[1]
+      case strings.Contains(m[0], "iPhone"):
+        r.OS, r.OSVersion = "iOS", strings.Replace(m[1], "_", ".", -1)
+      case strings.Contains(m[0], "Android"):
+        r.OS, r.OSVersion = "Android", m[1]
+      case strings.Contains(m[0], "Linux"):
+        r.OS = "Linux"
+      }
+      break
+    }
+  }
+
+  // 2. 浏览器 + 版本（按优先级匹配）
+  browserRe := []struct {
+    re   *regexp.Regexp
+    name string
+  }{
+    {regexp.MustCompile(`Edg/([\d.]+)`), "Edge"},
+    {regexp.MustCompile(`Chrome/([\d.]+)`), "Chrome"},
+    {regexp.MustCompile(`Firefox/([\d.]+)`), "Firefox"},
+    {regexp.MustCompile(`Version/([\d.]+).*Safari`), "Safari"},
+    {regexp.MustCompile(`OPR/([\d.]+)`), "Opera"},
+  }
+  for _, b := range browserRe {
+    if m := b.re.FindStringSubmatch(ua); len(m) > 1 {
+      r.Browser, r.BrowserVer = b.name, m[1]
+      break
+    }
+  }
+
+  return r
+}