From ce9fc3516acb9fcc72dc63469c66d59da681b5bc Mon Sep 17 00:00:00 2001
From: Asara <amarpreet@minhas.io>
Date: Sun, 31 Dec 2023 20:08:48 -0500
Subject: [PATCH] feat: first pass at lnurlp

---
 lnurlp/lnurlp.go | 62 ++++++++++++++++++++++++++++++++++++++++++++++++
 main.go          | 14 +++++++++--
 redis/redis.go   | 10 ++++----
 3 files changed, 80 insertions(+), 6 deletions(-)
 create mode 100644 lnurlp/lnurlp.go

diff --git a/lnurlp/lnurlp.go b/lnurlp/lnurlp.go
new file mode 100644
index 0000000..b8abab6
--- /dev/null
+++ b/lnurlp/lnurlp.go
@@ -0,0 +1,62 @@
+package lnurlp
+
+import (
+	"context"
+	b64 "encoding/base64"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strings"
+
+	"git.minhas.io/asara/well-goknown/logger"
+	"git.minhas.io/asara/well-goknown/redis"
+)
+
+type ErrorMessage struct {
+	Error string `json:"error"`
+}
+
+type Response struct {
+	Payload string `json:"request_key"`
+}
+
+func GetLnurlpUser(w http.ResponseWriter, r *http.Request) {
+	ctx := context.TODO()
+	l := logger.Get()
+
+	// connect to redis
+	redisCli := redis.LnurlpRedisConn.Client
+
+	// search for user@domain
+	search := getRkey("lnurlp", "asara", r.Host)
+	addr, err := redisCli.Get(ctx, search).Result()
+	if err != nil {
+		l.Info().Msg(fmt.Sprintf("get %s: not found", search))
+		w.WriteHeader(http.StatusNotFound)
+		json.NewEncoder(w).Encode(&ErrorMessage{
+			Error: "username not registered",
+		})
+		return
+	}
+	dec, err := b64.StdEncoding.DecodeString(addr)
+	if err != nil {
+		l.Error().Msg(fmt.Sprintf("get %s: unable to decode key", search))
+		w.WriteHeader(http.StatusInternalServerError)
+		json.NewEncoder(w).Encode(&ErrorMessage{
+			Error: "internal server error",
+		})
+		return
+	}
+
+	l.Info().Msg(fmt.Sprintf("get %s: found and returned", search))
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	w.Write(dec)
+}
+
+func getRkey(prefix string, user string, hostname string) string {
+	if strings.Contains(hostname, ":") {
+		hostname = strings.Split(hostname, ":")[0]
+	}
+	return fmt.Sprintf("%s:%s@%s", prefix, user, hostname)
+}
diff --git a/main.go b/main.go
index 2c71dfa..ef256d3 100644
--- a/main.go
+++ b/main.go
@@ -4,6 +4,7 @@ import (
 	"net/http"
 
 	"git.minhas.io/asara/well-goknown/config"
+	"git.minhas.io/asara/well-goknown/lnurlp"
 	"git.minhas.io/asara/well-goknown/logger"
 	"git.minhas.io/asara/well-goknown/matrix"
 	"git.minhas.io/asara/well-goknown/nostr"
@@ -22,6 +23,10 @@ func main() {
 	if err != nil {
 		l.Fatal().Msg("unable to connect to redis")
 	}
+	redis.LnurlpRedisConn, err = redis.New("localhost:6379", "", redis.LnurlpKeyspace)
+	if err != nil {
+		l.Fatal().Msg("unable to connect to redis")
+	}
 
 	// matrix endpoints
 	l.Debug().Msg("enabling matrix server endpoint")
@@ -33,12 +38,17 @@ func main() {
 	l.Debug().Msg("enabling nostr user endpoint")
 	http.HandleFunc("/.well-known/nostr.json", nostr.GetNostrAddr)
 
-	addr := config.GetConfig().LndAddr
-	if addr != "" {
+	// enable requesting of nostr addresses
+	lndAddr := config.GetConfig().LndAddr
+	if lndAddr != "" {
 		l.Debug().Msg("enabling nostr request endpoint")
 		http.HandleFunc("/request/nostr", nostr.RequestNostrAddr)
 	}
 
+	//lnurlp endpoints
+	l.Debug().Msg("enabling lnurlp endpoint")
+	http.HandleFunc("/.well-known/lnurlp/", lnurlp.GetLnurlpUser)
+
 	// start server
 	port := config.GetConfig().ListenAddr
 	l.Info().Msgf("starting server on %s", port)
diff --git a/redis/redis.go b/redis/redis.go
index e892e60..ae474bf 100644
--- a/redis/redis.go
+++ b/redis/redis.go
@@ -7,8 +7,9 @@ import (
 )
 
 const (
-	NostrKeyspace = iota
-	LndKeyspace   = iota
+	NostrKeyspace  = iota
+	LndKeyspace    = iota
+	LnurlpKeyspace = iota
 )
 
 type Redis struct {
@@ -16,8 +17,9 @@ type Redis struct {
 }
 
 var (
-	NostrRedisConn *Redis
-	LndRedisConn   *Redis
+	NostrRedisConn  *Redis
+	LndRedisConn    *Redis
+	LnurlpRedisConn *Redis
 )
 
 func New(address string, password string, database int) (*Redis, error) {