From e6a260270f92eae3d6b6e59d06c86058c027aa7f Mon Sep 17 00:00:00 2001
From: Sebastian Mark <smark@posteo.net>
Date: Sat, 19 Oct 2024 00:39:29 +0200
Subject: [PATCH] Genesis

---
 GoTomato.go | 113 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 README.md   |  12 ++++++
 go.mod      |   5 +++
 go.sum      |   2 +
 index.html  |  27 +++++++++++++
 5 files changed, 159 insertions(+)
 create mode 100644 GoTomato.go
 create mode 100644 README.md
 create mode 100644 go.mod
 create mode 100644 go.sum
 create mode 100644 index.html

diff --git a/GoTomato.go b/GoTomato.go
new file mode 100644
index 0000000..374f5c9
--- /dev/null
+++ b/GoTomato.go
@@ -0,0 +1,113 @@
+package main
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/gorilla/websocket"
+)
+
+const (
+	workDuration       = 15 * 60
+	shortBreakDuration = 5 * 60
+	longBreakDuration  = 10 * 60
+	sessions           = 4
+)
+
+type BroadcastMessage struct {
+	Mode       string `json:"mode"`
+	Session    int    `json:"session"`
+	MaxSession int    `json:"max_session"`
+	TimeLeft   int    `json:"time_left"`
+}
+
+var clients = make(map[*websocket.Conn]bool)
+
+// broadcastMessage sends the remaining time to all connected clients.
+func broadcastMessage(message BroadcastMessage) {
+	jsonMessage, _ := json.Marshal(message)
+	for client := range clients {
+		err := client.WriteMessage(websocket.TextMessage, jsonMessage)
+		if err != nil {
+			log.Printf("Error broadcasting to client: %v", err)
+			client.Close()
+			delete(clients, client)
+		}
+	}
+}
+
+// start a countdown and broadcast ever second
+func startTimer(remaining_seconds int, mode string, session int) {
+	for remaining_seconds > 0 {
+		broadcastMessage(BroadcastMessage{
+			Mode:       mode,
+			Session:    session,
+			MaxSession: sessions,
+			TimeLeft:   remaining_seconds,
+		})
+		time.Sleep(time.Second)
+		remaining_seconds--
+	}
+	// send final 0 timer
+	broadcastMessage(BroadcastMessage{
+		Mode:       mode,
+		Session:    1,
+		MaxSession: 4,
+		TimeLeft:   0,
+	})
+}
+
+// iterate the Pomodoro work/break sessions
+func runPomodoroTimer() {
+	for session := 1; session <= sessions; session++ {
+		startTimer(workDuration, "Work", session)
+		if session == sessions {
+			startTimer(longBreakDuration, "LongBreak", session)
+		} else {
+			startTimer(shortBreakDuration, "ShortBreak", session)
+		}
+	}
+}
+
+// upgrade HTTP requests to WebSocket connections.
+var upgrader = websocket.Upgrader{
+	CheckOrigin: func(r *http.Request) bool { return true },
+}
+
+func handleConnections(w http.ResponseWriter, r *http.Request) {
+	// Upgrade initial GET request to a WebSocket
+	ws, err := upgrader.Upgrade(w, r, nil)
+	if err != nil {
+		log.Printf("WebSocket upgrade error: %v", err)
+		return
+	}
+	defer ws.Close()
+
+	// Register the new client
+	clients[ws] = true
+
+	// Clean up when the client disconnects
+	for {
+		_, _, err := ws.ReadMessage()
+		if err != nil {
+			log.Printf("Client disconnected: %v", err)
+			delete(clients, ws)
+			break
+		}
+	}
+}
+
+func main() {
+	http.HandleFunc("/ws", handleConnections)
+
+	// Start a goroutine that runs the Pomodoro timer and broadcasts updates.
+	go runPomodoroTimer()
+
+	log.Println("Pomodoro WebSocket server started on :8080")
+	err := http.ListenAndServe(":8080", nil)
+	if err != nil {
+		log.Fatalf("Error starting server: %v", err)
+	}
+}
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..bca3c1f
--- /dev/null
+++ b/README.md
@@ -0,0 +1,12 @@
+# GoTomato
+
+A pomodoro server written in Go
+
+## Testing
+
+```
+docker run --rm -d --name pomodoro-client -v $PWD:/usr/share/nginx/html/ -p 8081:80 nginx
+go run .
+```
+
+open http://localhost:8081
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..ca20fd0
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module GoTomato
+
+go 1.23.1
+
+require github.com/gorilla/websocket v1.5.3 // indirect
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..25a9fc4
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,2 @@
+github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
+github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
diff --git a/index.html b/index.html
new file mode 100644
index 0000000..a092d2f
--- /dev/null
+++ b/index.html
@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+	<meta charset="UTF-8">
+	<meta name="viewport" content="width=device-width, initial-scale=1.0">
+	<title>Pomodoro Timer</title>
+</head>
+
+<body>
+	<h1>Pomodoro Timer</h1>
+	<div id="timer">Connecting to server...</div>
+
+	<script>
+		var ws = new WebSocket("ws://localhost:8080/ws");
+
+		ws.onmessage = function (event) {
+			document.getElementById("timer").innerText = event.data;
+		};
+
+		ws.onclose = function () {
+			document.getElementById("timer").innerText = "Connection closed.";
+		};
+	</script>
+</body>
+
+</html>