From b987605cfbbb5ca7b3b4bda0b5a5fdb34c53c8dd Mon Sep 17 00:00:00 2001
From: Kyren223 <ulmliad223@gmail.com>
Date: Sat, 5 Oct 2024 15:27:40 +0300
Subject: [PATCH] feat: basic server connection handling

---
 cmd/server/server.go         |  6 +--
 internal/server/handler.go   | 32 +++++++++++++++
 internal/server/server.go    | 79 ++++++++++++++++++++++++++++++++++++
 internal/utils/log/log.go    |  8 ++--
 internal/utils/log/logger.go | 12 +++---
 5 files changed, 123 insertions(+), 14 deletions(-)
 create mode 100644 internal/server/handler.go
 create mode 100644 internal/server/server.go

diff --git a/cmd/server/server.go b/cmd/server/server.go
index a1dee90..78e38f3 100644
--- a/cmd/server/server.go
+++ b/cmd/server/server.go
@@ -3,13 +3,11 @@ package main
 import (
 	"os"
 
+	"github.com/kyren223/eko/internal/server"
 	"github.com/kyren223/eko/internal/utils/log"
 )
 
 func main() {
 	log.SetDefault(log.NewLogger("Server", os.Stdout, true))
-	log.Debug("Eko 'Hello, World!'")
-	log.Info("Eko 'Hello, World!'")
-	log.Warn("Eko 'Hello, World!'")
-	log.Error("Eko 'Hello, World!'")
+	server.Start()
 }
diff --git a/internal/server/handler.go b/internal/server/handler.go
new file mode 100644
index 0000000..68a7cd2
--- /dev/null
+++ b/internal/server/handler.go
@@ -0,0 +1,32 @@
+package server
+
+import (
+	"net"
+	"sync"
+
+	"github.com/kyren223/eko/internal/utils/log"
+)
+
+func handleClient(conn net.Conn, wg *sync.WaitGroup) {
+	log.Info("Handling client... %v", conn.RemoteAddr().String())
+	defer log.Info("Disconnecting client: %v", conn.RemoteAddr().String())
+	defer conn.Close()
+	defer wg.Done()
+
+	var request []byte
+	n, err := conn.Read(request)
+	if err != nil {
+		log.Error("Failed reading: %v", err)
+		return
+	}
+	log.Info("Read %v bytes: %v", n, string(request))
+
+	response := []byte("Server response")
+	n, err = conn.Write(response)
+	if err != nil {
+		log.Error("Failed writing response: %v", err)
+		return
+	}
+	log.Info("Responded successfully")
+}
+
diff --git a/internal/server/server.go b/internal/server/server.go
new file mode 100644
index 0000000..c49df15
--- /dev/null
+++ b/internal/server/server.go
@@ -0,0 +1,79 @@
+package server
+
+import (
+	"net"
+	"os"
+	"os/signal"
+	"strconv"
+	"sync"
+	"syscall"
+
+	"github.com/kyren223/eko/internal/utils/log"
+)
+
+const PORT int = 7223
+
+func Start() {
+	server, err := NewServer(6969)
+	if err != nil {
+		log.Error("Unable to start server: %v", err)
+		return
+	}
+
+	var wg sync.WaitGroup
+	stopChan := make(chan os.Signal, 1)
+	signal.Notify(stopChan, syscall.SIGINT, syscall.SIGTERM)
+	wg.Add(1)
+	go handleInterrupt(server, stopChan, &wg)
+
+	server.Listen()
+	wg.Wait()
+}
+
+func handleInterrupt(server *Server, stopChan <-chan os.Signal, wg *sync.WaitGroup) {
+	defer wg.Done()
+	<-stopChan
+	log.Info("Interrupt Occurred")
+	log.Info("Shutting down server...")
+	server.Close()
+	log.Info("Waiting for all connections to close")
+	server.Wait()
+	log.Info("Server has been shutdown")
+}
+
+type Server struct {
+	listener net.Listener
+	wg       sync.WaitGroup
+}
+
+func NewServer(port int) (*Server, error) {
+	listener, err := net.Listen("tcp", ":"+strconv.Itoa(port))
+	if err != nil {
+		return nil, err
+	}
+
+	log.Info("Created server on port %v", port)
+	return &Server{listener, sync.WaitGroup{}}, nil
+}
+
+func (s *Server) Listen() {
+	log.Info("Server started listening... %v", s.listener.Addr().String())
+	for {
+		conn, err := s.listener.Accept()
+		if err != nil {
+			break
+		}
+		s.wg.Add(1)
+		go handleClient(conn, &s.wg)
+	}
+}
+
+// Stop stops the server. The blocked Listen call will be unlocked
+func (s *Server) Close() {
+	s.listener.Close()
+}
+
+// Wait blocks until all active connections to the server are done
+func (s *Server) Wait() {
+	s.wg.Wait()
+}
diff --git a/internal/utils/log/log.go b/internal/utils/log/log.go
index 724b074..366c54d 100644
--- a/internal/utils/log/log.go
+++ b/internal/utils/log/log.go
@@ -10,17 +10,17 @@ func SetDefault(l *Logger) {
 }
 
 func Debug(message string, a ...any) error {
-	return logger.Log(LevelDebug, message, a)
+	return logger.Debug(message, a...)
 }
 
 func Info(message string, a ...any) error {
-	return logger.Log(LevelInfo, message, a)
+	return logger.Info(message, a...)
 }
 
 func Warn(message string, a ...any) error {
-	return logger.Log(LevelWarn, message, a)
+	return logger.Warn(message, a...)
 }
 
 func Error(message string, a ...any) error {
-	return logger.Log(LevelError, message, a)
+	return logger.Error(message, a...)
 }
diff --git a/internal/utils/log/logger.go b/internal/utils/log/logger.go
index 735cb9e..891cb086 100644
--- a/internal/utils/log/logger.go
+++ b/internal/utils/log/logger.go
@@ -2,7 +2,6 @@ package log
 
 import (
 	"fmt"
-	"go/format"
 	"io"
 	"os"
 	"sync"
@@ -29,27 +28,28 @@ func (l *Logger) Log(level Level, message string, a ...any) error {
 
 	timestamp := time.Now().Format(time.TimeOnly)
 	severity := level.String()
+	formattedMessage := fmt.Sprintf(message, a...)
 
 	// TODO: add support for ANSI coloring
 	l.mu.Lock()
-	_, err := fmt.Fprintf(l.writer, "[%s] [%s/%s]: %s\n", timestamp, l.name, severity, message, a)
+	_, err := fmt.Fprintf(l.writer, "[%s] [%s/%s]: %s\n", timestamp, l.name, severity, formattedMessage)
 	l.mu.Unlock()
 	return err
 }
 
 func (l *Logger) Debug(message string, a ...any) error {
-	return l.Log(LevelDebug, message, a)
+	return l.Log(LevelDebug, message, a...)
 }
 
 func (l *Logger) Info(message string, a ...any) error {
-	return l.Log(LevelInfo, message, a)
+	return l.Log(LevelInfo, message, a...)
 }
 
 func (l *Logger) Warn(message string, a ...any) error {
-	return l.Log(LevelWarn, message, a)
+	return l.Log(LevelWarn, message, a...)
 }
 
 func (l *Logger) Error(message string, a ...any) error {
-	return l.Log(LevelError, message, a)
+	return l.Log(LevelError, message, a...)
 }