From 28e93b1fa370091099fb9b654ef1c5c87534dfc6 Mon Sep 17 00:00:00 2001
From: Paul Brinkmeier <hallo@pbrinkmeier.de>
Date: Sun, 15 Jan 2023 16:09:50 +0100
Subject: [PATCH] Set up simple chat server

---
 glebby-client/src/App.vue                   |  38 ++++++-
 glebby-client/src/components/Game.vue       | 102 +++++++++++++++++
 glebby-client/src/components/HelloWorld.vue |  15 ---
 glebby-server/glebby.py                     | 119 +++++++++++++++++++-
 4 files changed, 250 insertions(+), 24 deletions(-)
 create mode 100644 glebby-client/src/components/Game.vue
 delete mode 100644 glebby-client/src/components/HelloWorld.vue

diff --git a/glebby-client/src/App.vue b/glebby-client/src/App.vue
index f5b68e7..d751ca4 100644
--- a/glebby-client/src/App.vue
+++ b/glebby-client/src/App.vue
@@ -1,7 +1,39 @@
-<script setup lang="ts">
-import HelloWorld from './components/HelloWorld.vue'
+<script lang="ts">
+import Game from './components/Game.vue'
+
+/*
+Basically just opens the websocket connection to the server,
+waits for the 'init' message and passes the initial state to the Game
+component. Once the initial state has been received, no more event are processed.
+*/
+export default {
+  components: {
+    Game
+  },
+  data() {
+    return {
+      ws: new WebSocket('ws://localhost:5000/glebby'),
+      model: null
+    }
+  },
+  created() {
+    const messageListener = (ev: MessageEvent) => {
+      const message = JSON.parse(ev.data)
+      const payload = message.payload
+
+      if (payload.type === 'init') {
+        console.log('Received initial game state:')
+        console.log(payload.state)
+        this.model = payload.state
+        this.ws.removeEventListener('message', messageListener)
+      }
+    }
+
+    this.ws.addEventListener('message', messageListener)
+  }
+}
 </script>
 
 <template>
-  <HelloWorld msg="Vite + Vue" />
+  <Game v-if="model" :ws="ws" :model="model" />
 </template>
diff --git a/glebby-client/src/components/Game.vue b/glebby-client/src/components/Game.vue
new file mode 100644
index 0000000..4c783e0
--- /dev/null
+++ b/glebby-client/src/components/Game.vue
@@ -0,0 +1,102 @@
+<script lang="ts">
+import { defineComponent, PropType } from 'vue';
+
+interface Player {
+  id: number,
+  name: string
+}
+
+interface Model {
+  yourId: number,
+  players: Player[]
+}
+
+function getPlayer(model: Model, id: number): Player | undefined {
+  return model.players.find(player => player.id === id)
+}
+
+/*
+Handles all game business. Sends (local) player input to the server for distribution.
+Receives player input from the server and manages state accordingly.
+*/
+export default defineComponent({
+  props: {
+    ws: { type: WebSocket, required: true },
+    model: { type: Object as PropType<Model>, required: true }
+  },
+  data() {
+    return {
+      chatMessages: [] as string[],
+
+      playerName: '',
+      chatMessage: ''
+    }
+  },
+  created() {
+    this.ws.addEventListener('message', (ev) => {
+      const message = JSON.parse(ev.data)
+      const payload = message.payload
+      console.log(`Message from player ${message.from}:`)
+      console.log(payload)
+
+      switch (payload.type) {
+        case 'join':
+          this.model.players.push({
+            id: message.from,
+            name: ''
+          })
+          break
+        case 'leave':
+          this.model.players = this.model.players.filter(player => player.id !== message.from)
+          break
+        case 'chat':
+          this.chatMessages.push(payload.message)
+          break
+        case 'set-name':
+          getPlayer(this.model, message.from)!.name = payload.name
+          break
+      }
+    })
+  },
+  methods: {
+    setName() {
+      this.ws.send(JSON.stringify({
+        type: 'set-name',
+        name: this.playerName
+      }))
+    },
+    sendChat() {
+      if (this.chatMessage === '') {
+        return
+      }
+
+      this.ws.send(JSON.stringify({
+        type: 'chat',
+        message: this.chatMessage
+      }))
+      this.chatMessage = ''
+    }
+  }
+})
+</script>
+
+<template>
+  <pre>{{ JSON.stringify(model, null, 2) }}</pre>
+  <h1>I am #{{ model.yourId }}</h1>
+  <form @submit.prevent="setName">
+    <input v-model="playerName" placeholder="enter your name...">
+    <button >set name</button>
+  </form>
+  <form @submit.prevent="sendChat">
+    <input v-model="chatMessage">
+    <button>Post</button>
+  </form>
+  <h2>players</h2>
+  <ul v-if="model">
+    <li v-for="player in model.players" :key="player.id">{{ player.name }}#{{ player.id }}</li>
+  </ul>
+  <h2>chat</h2>
+  <ul v-if="model">
+    <li v-for="message in chatMessages">{{ message }}</li>
+  </ul>
+</template>
diff --git a/glebby-client/src/components/HelloWorld.vue b/glebby-client/src/components/HelloWorld.vue
deleted file mode 100644
index 6ca4084..0000000
--- a/glebby-client/src/components/HelloWorld.vue
+++ /dev/null
@@ -1,15 +0,0 @@
-<script setup lang="ts">
-import { ref } from 'vue'
-
-defineProps<{ msg: string }>()
-
-const count = ref(0)
-</script>
-
-<template>
-  <h1>{{ msg }}</h1>
-
-  <div class="card">
-    <button type="button" @click="count++">count is {{ count }}</button>
-  </div>
-</template>
diff --git a/glebby-server/glebby.py b/glebby-server/glebby.py
index 2e7dd04..d124b00 100644
--- a/glebby-server/glebby.py
+++ b/glebby-server/glebby.py
@@ -1,16 +1,123 @@
-from flask import Flask, render_template
-from flask_sock import Sock
+import json
 import simple_websocket
 
+from flask import Flask
+from flask_sock import Sock
+from queue import Queue
+from threading import Thread, Lock
+
+class Client:
+    def __init__(self, sock, client_id):
+        self.sock = sock
+        self.data = { 'id': client_id, 'name': '' }
+
+class GlebbyState:
+    def __init__(self):
+        self.clients_lock = Lock()
+        self.clients = dict()
+
+        self.next_client_id_lock = Lock()
+        self.next_client_id = 0
+
+        self.incoming_messages = Queue()
+    
+    # domain stuff
+
+    def handle_message_from(self, client_id, payload):
+        print(f"{client_id}: {payload}")
+
+        if payload['type'] == 'set-name':
+            self.clients[client_id].data['name'] = payload['name']
+            self.broadcast(client_id, {
+                'type': 'set-name',
+                'name': payload['name']
+            })
+        elif payload['type'] == 'chat':
+            self.broadcast(client_id, {
+                'type': 'chat',
+                'message': payload['message']
+            })
+        else:
+            print("Unhandled!")
+    
+    def get_state_dto(self, client_id):
+        return {
+            'yourId': client_id,
+            'players': [
+                self.clients[other_client_id].data
+                for other_client_id in self.clients
+            ]
+        }
+    
+    # message receiving and sending
+
+    def put_incoming_message(self, client_id, payload):
+        self.incoming_messages.put({
+            'from': client_id,
+            'payload': json.loads(payload)
+        })
+    
+    def send_to(self, client_id_from, client_id_to, payload):
+        self.clients[client_id_to].sock.send(json.dumps({
+            'from': client_id_from,
+            'payload': payload
+        }))
+
+    def broadcast(self, client_id_from, payload):
+        with self.clients_lock:
+            for client_id_to in self.clients:
+                self.send_to(client_id_from, client_id_to, payload)
+    
+    # client management
+
+    def _get_next_client_id(self):
+        with self.next_client_id_lock:
+            client_id = self.next_client_id
+            self.next_client_id += 1
+            return client_id
+
+    def add_client(self, sock):
+        client_id = self._get_next_client_id()
+        self.broadcast(client_id, {'type': 'join'})
+        with self.clients_lock:
+            self.clients[client_id] = Client(sock, client_id)
+        self.send_to(None, client_id, {
+            'type': 'init',
+            'state': self.get_state_dto(client_id)
+        })
+        return client_id
+    
+    def remove_client(self, client_id):
+        with self.clients_lock:
+            del self.clients[client_id]
+        self.broadcast(client_id, {'type': 'leave'})
+    
+    # event thread stuff
+
+    def start_event_thread(self):
+        event_thread = Thread(target=lambda: self._event_thread())
+        event_thread.daemon = True
+        event_thread.start()
+    
+    def _event_thread(self):
+        while True:
+            msg = self.incoming_messages.get()
+            self.handle_message_from(msg['from'], msg['payload'])
+
+# Initialization
+
+state = GlebbyState()
+state.start_event_thread()
+
 app = Flask(__name__)
 sock = Sock(app)
 
-@sock.route('/echo')
+@sock.route('/glebby')
 def echo(sock):
-    print('New echo client')
+    client_id = state.add_client(sock)
     try:
         while True:
             data = sock.receive()
-            sock.send(data)
+            state.put_incoming_message(client_id, data)
     except simple_websocket.ConnectionClosed:
-        print("Client closed the connection")
+        state.remove_client(client_id)