From dbe9068b0b9dd394d51451c13e130a3bf363f603 Mon Sep 17 00:00:00 2001
From: Andrew Beal <andrew.business@tuta.com>
Date: Sun, 28 Sep 2025 14:57:58 +0100
Subject: [PATCH] Add MessageService and AIThoughtMessage component

---
 Components/ChatArea.svelte        | 27 ++++++----------
 Components/ChatAreaThought.svelte | 53 +++++++++++++++++++++++++++++++
 Messages/AIThoughtMessage.ts      |  7 ++++
 Messages/IMessage.ts              |  3 ++
 Services/MessageService.ts        | 29 +++++++++++++++++
 Services/ServiceRegistration.ts   |  2 ++
 Services/Services.ts              |  1 +
 7 files changed, 104 insertions(+), 18 deletions(-)
 create mode 100644 Components/ChatAreaThought.svelte
 create mode 100644 Messages/AIThoughtMessage.ts
 create mode 100644 Messages/IMessage.ts
 create mode 100644 Services/MessageService.ts

diff --git a/Components/ChatArea.svelte b/Components/ChatArea.svelte
index 7286042..a04ae10 100644
--- a/Components/ChatArea.svelte
+++ b/Components/ChatArea.svelte
@@ -2,11 +2,13 @@
   import { Resolve } from "Services/DependencyService";
   import { Services } from "Services/Services";
   import type { StreamingMarkdownService } from "Services/StreamingMarkdownService";
+	import ChatAreaThought from "./ChatAreaThought.svelte";
 
   export let messages: Array<{id: string, content: string, isUser: boolean, isStreaming: boolean}> = [];
   
-  let chatContainer: HTMLDivElement;
   let streamingMarkdownService: StreamingMarkdownService = Resolve(Services.StreamingMarkdownService);
+
+  let chatContainer: HTMLDivElement;
   let messageElements = new Map<string, HTMLElement>();
   let lastProcessedContent = new Map<string, string>();
 
@@ -30,10 +32,8 @@
     if (!element) return;
 
     if (message.isStreaming) {
-      // Use streaming update
       streamingMarkdownService.streamChunk(message.id, message.content);
     } else {
-      // Finalize the message
       streamingMarkdownService.finalizeStream(message.id, message.content);
     }
   }
@@ -49,7 +49,6 @@
     
     return {
       destroy() {
-        // Cleanup when element is removed
         messageElements.delete(messageId);
       }
     };
@@ -74,12 +73,6 @@
     return ''; // Streaming messages will be handled by the streaming service
   }
 
-  // Clean up when component is destroyed
-  function cleanup() {
-    messageElements.clear();
-    lastProcessedContent.clear();
-  }
-
   // Make sure to clean up when messages are removed
   $: {
     const currentMessageIds = new Set(messages.map(m => m.id));
@@ -102,16 +95,14 @@
           <p>{message.content}</p>
         {:else}
           <div class="markdown-content" class:streaming={message.isStreaming}>
+            <!-- Streaming message: use action for initialization -->
             {#if message.isStreaming}
-              <!-- Streaming message: use action for initialization -->
-              <div 
-                use:streamingAction={message.id}
-                class="streaming-content"
-              ></div>
-              <span class="streaming-indicator">● ● ●</span>
+            <div use:streamingAction={message.id} class="streaming-content"></div>
+            <span class="streaming-indicator">● ● ●</span>
+            <ChatAreaThought/>
             {:else}
-              <!-- Static message: use traditional rendering -->
-              {@html getStaticHTML(message)}
+            <!-- Static message: use traditional rendering -->
+            {@html getStaticHTML(message)}
             {/if}
           </div>
         {/if}
diff --git a/Components/ChatAreaThought.svelte b/Components/ChatAreaThought.svelte
new file mode 100644
index 0000000..8a2d015
--- /dev/null
+++ b/Components/ChatAreaThought.svelte
@@ -0,0 +1,53 @@
+<script lang="ts">
+	import { AIThoughtMessage } from "Messages/AIThoughtMessage";
+    import { Resolve } from "Services/DependencyService";
+	import type { MessageService } from "Services/MessageService";
+    import { Services } from "Services/Services";
+    import { onDestroy } from "svelte";
+	import { fade } from "svelte/transition";
+  
+    let messageService: MessageService = Resolve(Services.MessageService);
+    let currentThought: string | null = null;
+    let isVisible: boolean = false;
+  
+    // Handler for AI thought messages
+    function handleAIThought(message: AIThoughtMessage): void {
+      currentThought = message.thought;
+      isVisible = currentThought !== null && currentThought.trim().length > 0;
+    }
+  
+    messageService.register(AIThoughtMessage, handleAIThought);
+  
+    onDestroy(() => {
+      messageService.unregister(AIThoughtMessage, handleAIThought);
+    });
+  </script>
+  
+  {#if isVisible && currentThought}
+    <div class="ai-thought-container" in:fade={{ duration: 200 }} out:fade={{ duration: 200 }}>
+      <div class="ai-thought-bubble">
+        <span>{currentThought}</span>
+      </div>
+    </div>
+  {/if}
+  
+  <style>
+    .ai-thought-container {
+      margin-top: var(--size-2-1);
+      margin-bottom: var(--size-2-1);
+    }
+  
+    .ai-thought-bubble {
+      display: inline-flex;
+      align-items: center;
+      background: var(--metadata-background);
+      border: var(--border-width) solid var(--metadata-border-color);
+      border-radius: var(--metadata-border-radius);
+      padding: var(--metadata-padding);
+      font-size: var(--metadata-label-font-size);
+      color: var(--text-muted);
+      font-style: italic;
+      max-width: 100%;
+      word-wrap: break-word;
+    }
+  </style>
\ No newline at end of file
diff --git a/Messages/AIThoughtMessage.ts b/Messages/AIThoughtMessage.ts
new file mode 100644
index 0000000..2ff42d8
--- /dev/null
+++ b/Messages/AIThoughtMessage.ts
@@ -0,0 +1,7 @@
+import type { IMessage } from "./IMessage";
+
+export class AIThoughtMessage implements IMessage {
+    constructor(public thought: string | null) {}
+    invoke(): void {
+    }
+}
\ No newline at end of file
diff --git a/Messages/IMessage.ts b/Messages/IMessage.ts
new file mode 100644
index 0000000..a90fe4f
--- /dev/null
+++ b/Messages/IMessage.ts
@@ -0,0 +1,3 @@
+export interface IMessage {
+    invoke(): void;
+  }
\ No newline at end of file
diff --git a/Services/MessageService.ts b/Services/MessageService.ts
new file mode 100644
index 0000000..3a3a510
--- /dev/null
+++ b/Services/MessageService.ts
@@ -0,0 +1,29 @@
+import type { IMessage } from "Messages/IMessage";
+
+type MessageConstructor<T extends IMessage> = new (...args: any[]) => T;
+
+export class MessageService {
+  private handlers = new Map<MessageConstructor<any>, Set<(message: any) => void>>();
+
+  register<T extends IMessage>(messageType: MessageConstructor<T>, handler: (message: T) => void): void {
+    if (!this.handlers.has(messageType)) {
+      this.handlers.set(messageType, new Set());
+    }
+    
+    let messageHandler: Set<(message: any) => void> | undefined = this.handlers.get(messageType);
+    
+    if (messageHandler != null) {
+        messageHandler.add(handler);
+    }
+  }
+
+  unregister<T extends IMessage>(messageType: MessageConstructor<T>, handler: (message: T) => void): void {
+    this.handlers.get(messageType)?.delete(handler);
+  }
+
+  send<T extends IMessage>(message: T): void {
+    const messageType = message.constructor as MessageConstructor<T>;
+    const handlers = this.handlers.get(messageType);
+    handlers?.forEach(handler => handler(message));
+  }
+}
\ No newline at end of file
diff --git a/Services/ServiceRegistration.ts b/Services/ServiceRegistration.ts
index b39be3e..733c5cc 100644
--- a/Services/ServiceRegistration.ts
+++ b/Services/ServiceRegistration.ts
@@ -12,8 +12,10 @@ import { GeminiActionDefinitions } from "Actioner/Gemini/GeminiActionDefinitions
 import type { IActionDefinitions } from "Actioner/IActionDefinitions";
 import { Gemini } from "AIClasses/Gemini/Gemini";
 import { StreamingMarkdownService } from "./StreamingMarkdownService";
+import { MessageService } from "./MessageService";
 
 export function RegisterDependencies(plugin: DmsAssistantPlugin) {
+    RegisterSingleton(Services.MessageService, new MessageService());
     RegisterSingleton(Services.DmsAssistantPlugin, plugin);
     RegisterSingleton(Services.OdbCache, new OdbCache());
     RegisterSingleton(Services.ModalService, new ModalService())
diff --git a/Services/Services.ts b/Services/Services.ts
index 6e6d052..dcfd690 100644
--- a/Services/Services.ts
+++ b/Services/Services.ts
@@ -1,4 +1,5 @@
 export class Services {
+    static MessageService = Symbol("MessageService");
     static DmsAssistantPlugin = Symbol("DmsAssistantPlugin");
     static OdbCache = Symbol("OdbCache");
     static ModalService = Symbol("ModalService");