From 9c571f4c231a7edce2119ca7a89a5d550a297527 Mon Sep 17 00:00:00 2001
From: Mike Cheng <michael.cheng@kik.com>
Date: Sat, 2 May 2015 22:17:13 -0400
Subject: [PATCH] Initial work on daemon

---
 dyndns/daemon.go | 71 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 dyndns/daemon.go

diff --git a/dyndns/daemon.go b/dyndns/daemon.go
new file mode 100644
index 0000000..2c2111b
--- /dev/null
+++ b/dyndns/daemon.go
@@ -0,0 +1,71 @@
+package dyndns
+
+import (
+	"fmt"
+	"github.com/mfycheng/name-dyndns/api"
+	"sync"
+	"time"
+)
+
+var wg sync.WaitGroup
+
+func updateDomain(a api.API, currentIP, domain string) error {
+	records, err := api.GetRecords(domain)
+	if err != nil {
+		return err
+	}
+
+	if len(records) == 0 {
+		return nil
+	}
+
+	for _, record := range records {
+		if record.Content != currentIP {
+			// TODO: Update
+		}
+	}
+
+	return nil
+}
+
+func runConfig(c api.Config, daemon bool) {
+	defer wg.Done()
+
+	a := api.NewAPIFromConfig(c)
+	for {
+		ip, err := GetExternalIP()
+		if err != nil {
+			fmt.Print("Failed to retreive IP: ")
+			if daemon {
+				fmt.Println("Will retry...")
+				continue
+			} else {
+				fmt.Println("Giving up.")
+				break
+			}
+		}
+
+		for _, domain := range c.Domains {
+			updateDomain(a, ip, domain)
+		}
+
+		if !daemon {
+			return
+		}
+
+		time.Sleep(time.Duration(c.Interval) * time.Second)
+	}
+}
+
+// For each domain, check if the host record matches
+// the current external IP. If it does not, it updates.
+// If daemon is true, then Run will run forever, polling at
+// an interval specified in each config.
+func Run(configs []api.Config, daemon bool) {
+	for _, config := range configs {
+		wg.Add(1)
+		go runConfig(config, daemon)
+	}
+
+	wg.Wait()
+}