From 980a8bf16f8936f4ad6238b1e29e590d0513f76c Mon Sep 17 00:00:00 2001
From: Robert Gerus <arachnist@i.am-a.cat>
Date: Mon, 13 Jun 2016 19:22:21 +0200
Subject: [PATCH] Store tips fetched from api and only fetch a new batch when
 we've ran out of tips.

---
 bot/frog.go | 56 ++++++++++++++++++++++++++++++++++++-----------------
 1 file changed, 38 insertions(+), 18 deletions(-)

diff --git a/bot/frog.go b/bot/frog.go
index ea5afbd..a43cec1 100644
--- a/bot/frog.go
+++ b/bot/frog.go
@@ -7,8 +7,8 @@ package bot
 import (
 	"encoding/json"
 	"fmt"
-	"math/rand"
 	"strings"
+	"sync"
 
 	"github.com/arachnist/gorepost/irc"
 )
@@ -20,30 +20,50 @@ type tip struct {
 
 type tips struct {
 	Tips []tip `json:"tips"`
+	lock sync.RWMutex
 }
 
-func frog(output func(irc.Message), msg irc.Message) {
-	var values tips
+func (tips *tips) fetchTips() error {
+	tips.lock.Lock()
+	defer tips.lock.Unlock()
 
+	data, err := httpGet("http://frog.tips/api/1/tips/")
+	if err != nil {
+		return err
+	}
+
+	err = json.Unmarshal(data, tips)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (tips *tips) popTip() string {
+	if len(tips.Tips) == 0 {
+		if err := tips.fetchTips(); err != nil {
+			return fmt.Sprint(err)
+		}
+	}
+
+	tips.lock.RLock()
+	defer tips.lock.RUnlock()
+
+	rmsg := tips.Tips[len(tips.Tips)-1].Tip
+	tips.Tips = tips.Tips[:len(tips.Tips)-1]
+
+	return rmsg
+}
+
+var t tips
+
+func frog(output func(irc.Message), msg irc.Message) {
 	if strings.Split(msg.Trailing, " ")[0] != ":frog" {
 		return
 	}
 
-	data, err := httpGet("http://frog.tips/api/1/tips/")
-	if err != nil {
-		output(reply(msg, fmt.Sprint("error:", err)))
-		return
-	}
-
-	err = json.Unmarshal(data, &values)
-	if err != nil {
-		output(reply(msg, fmt.Sprint("error:", err)))
-		return
-	}
-
-	tip := values.Tips[rand.Intn(len(values.Tips))]
-
-	output(reply(msg, fmt.Sprintf("frog tip #%d: %s", tip.Number, tip.Tip)))
+	output(reply(msg, t.popTip()))
 }
 
 func init() {