From 94c1f231a2ecb6dd147d3bbf6735e0d13be309fb Mon Sep 17 00:00:00 2001
From: lawlielt <lawlielt.liu@gmail.com>
Date: Tue, 7 May 2024 11:21:52 +0000
Subject: [PATCH] feat: add GetNationalPrefix method

---
 phonenumbers.go      |  9 +++++++++
 phonenumbers_test.go | 21 +++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/phonenumbers.go b/phonenumbers.go
index fb5ea06..f3b23b4 100644
--- a/phonenumbers.go
+++ b/phonenumbers.go
@@ -3486,3 +3486,12 @@ func GetGeocodingForNumber(number *PhoneNumber, lang string) (string, error) {
 	}
 	return display.Regions(langT).Name(reg), nil
 }
+
+// GetNationalPrefix return the region national prefix of the number
+func GetNationalPrefix(number *PhoneNumber) string {
+	metadata := getMetadataForRegion(GetRegionCodeForNumber(number))
+	if metadata == nil {
+		return ""
+	}
+	return metadata.GetNationalPrefix()
+}
diff --git a/phonenumbers_test.go b/phonenumbers_test.go
index 9cce22b..8df3315 100644
--- a/phonenumbers_test.go
+++ b/phonenumbers_test.go
@@ -1679,6 +1679,27 @@ func TestGetSafeCarrierDisplayNameForNumber(t *testing.T) {
 	}
 }
 
+func TestGetNationalPrefix(t *testing.T) {
+	tests := []struct {
+		num      string
+		expected string
+	}{
+		{num: "+1213-290-1064", expected: "1"},
+		{num: "+8601087777777", expected: "0"},
+		{num: "+442079460958", expected: "0"},
+	}
+	for _, test := range tests {
+		number, err := Parse(test.num, "CN")
+		if err != nil {
+			t.Errorf("Failed to parse number %s: %s", test.num, err)
+		}
+		nationalPrefix := GetNationalPrefix(number)
+		if test.expected != nationalPrefix {
+			t.Errorf("Expected '%s', got '%s' for '%s'", test.expected, nationalPrefix, test.num)
+		}
+	}
+}
+
 func s(str string) *string {
 	return &str
 }