init commit

core/ping.go

@@ -0,0 +1,78 @@
+package core
+
+import (
+	"net"
+	"sync"
+	"time"
+)
+
+// PingResult contains the result of a ping to a server.
+type PingResult struct {
+	Ms    int64 // round-trip time in ms, -1 if failed
+	Color string
+}
+
+// PingAddress pings a single address using TCP connect (ICMP requires elevated privileges).
+// Returns round-trip time in ms or -1 on failure.
+func PingAddress(address string, timeout time.Duration) int64 {
+	if timeout == 0 {
+		timeout = 3 * time.Second
+	}
+
+	start := time.Now()
+	conn, err := net.DialTimeout("tcp", address+":443", timeout)
+	if err != nil {
+		return -1
+	}
+	conn.Close()
+	return time.Since(start).Milliseconds()
+}
+
+// PingConfig pings a VPN config and returns the result.
+func PingConfig(config *VpnConfig) PingResult {
+	link := TryParseLink(config.Link)
+	if link == nil {
+		return PingResult{Ms: -1, Color: "#666"}
+	}
+
+	ms := PingAddress(link.Address, 3*time.Second)
+	if ms < 0 {
+		return PingResult{Ms: -1, Color: "#666"}
+	}
+	return PingResult{Ms: ms, Color: GetPingColor(ms)}
+}
+
+// PingAllConfigs pings all configs concurrently.
+func PingAllConfigs(configs []VpnConfig) []PingResult {
+	results := make([]PingResult, len(configs))
+	var wg sync.WaitGroup
+
+	for i := range configs {
+		wg.Add(1)
+		go func(idx int) {
+			defer wg.Done()
+			results[idx] = PingConfig(&configs[idx])
+		}(i)
+	}
+
+	wg.Wait()
+	return results
+}
+
+// GetPingColor returns a color hex code based on ping latency.
+func GetPingColor(ms int64) string {
+	switch {
+	case ms < 50:
+		return "#4CAF50" // green
+	case ms < 100:
+		return "#8BC34A" // light green
+	case ms < 150:
+		return "#CDDC39" // lime
+	case ms < 200:
+		return "#FFC107" // amber
+	case ms < 300:
+		return "#FF9800" // orange
+	default:
+		return "#E53935" // red
+	}
+}