fix(core): Enhanced chat streaming and error handling across providers

ts/provider.ollama.ts

@@ -1,3 +1,170 @@
 import * as plugins from './plugins.js';
+import * as paths from './paths.js';
+import { MultiModalModel } from './abstract.classes.multimodal.js';
+import type { ChatOptions, ChatResponse, ChatMessage } from './abstract.classes.multimodal.js';
 
-export class OllamaProvider {}
+export interface IOllamaProviderOptions {
+  baseUrl?: string;
+  model?: string;
+}
+
+export class OllamaProvider extends MultiModalModel {
+  private options: IOllamaProviderOptions;
+  private baseUrl: string;
+  private model: string;
+
+  constructor(optionsArg: IOllamaProviderOptions = {}) {
+    super();
+    this.options = optionsArg;
+    this.baseUrl = optionsArg.baseUrl || 'http://localhost:11434';
+    this.model = optionsArg.model || 'llama2';
+  }
+
+  async start() {
+    // Verify Ollama is running
+    try {
+      const response = await fetch(`${this.baseUrl}/api/tags`);
+      if (!response.ok) {
+        throw new Error('Failed to connect to Ollama server');
+      }
+    } catch (error) {
+      throw new Error(`Failed to connect to Ollama server at ${this.baseUrl}: ${error.message}`);
+    }
+  }
+
+  async stop() {}
+
+  public async chatStream(input: ReadableStream<Uint8Array>): Promise<ReadableStream<string>> {
+    // Create a TextDecoder to handle incoming chunks
+    const decoder = new TextDecoder();
+    let buffer = '';
+    let currentMessage: { role: string; content: string; } | null = null;
+
+    // Create a TransformStream to process the input
+    const transform = new TransformStream<Uint8Array, string>({
+      async transform(chunk, controller) {
+        buffer += decoder.decode(chunk, { stream: true });
+
+        // Try to parse complete JSON messages from the buffer
+        while (true) {
+          const newlineIndex = buffer.indexOf('\n');
+          if (newlineIndex === -1) break;
+
+          const line = buffer.slice(0, newlineIndex);
+          buffer = buffer.slice(newlineIndex + 1);
+
+          if (line.trim()) {
+            try {
+              const message = JSON.parse(line);
+              currentMessage = {
+                role: message.role || 'user',
+                content: message.content || '',
+              };
+            } catch (e) {
+              console.error('Failed to parse message:', e);
+            }
+          }
+        }
+
+        // If we have a complete message, send it to Ollama
+        if (currentMessage) {
+          const response = await fetch(`${this.baseUrl}/api/chat`, {
+            method: 'POST',
+            headers: {
+              'Content-Type': 'application/json',
+            },
+            body: JSON.stringify({
+              model: this.model,
+              messages: [{ role: currentMessage.role, content: currentMessage.content }],
+              stream: true,
+            }),
+          });
+
+          // Process each chunk from Ollama
+          const reader = response.body?.getReader();
+          if (reader) {
+            try {
+              while (true) {
+                const { done, value } = await reader.read();
+                if (done) break;
+
+                const chunk = new TextDecoder().decode(value);
+                const lines = chunk.split('\n');
+
+                for (const line of lines) {
+                  if (line.trim()) {
+                    try {
+                      const parsed = JSON.parse(line);
+                      const content = parsed.message?.content;
+                      if (content) {
+                        controller.enqueue(content);
+                      }
+                    } catch (e) {
+                      console.error('Failed to parse Ollama response:', e);
+                    }
+                  }
+                }
+              }
+            } finally {
+              reader.releaseLock();
+            }
+          }
+
+          currentMessage = null;
+        }
+      },
+
+      flush(controller) {
+        if (buffer) {
+          try {
+            const message = JSON.parse(buffer);
+            controller.enqueue(message.content || '');
+          } catch (e) {
+            console.error('Failed to parse remaining buffer:', e);
+          }
+        }
+      }
+    });
+
+    // Connect the input to our transform stream
+    return input.pipeThrough(transform);
+  }
+
+  // Implementing the synchronous chat interaction
+  public async chat(optionsArg: ChatOptions): Promise<ChatResponse> {
+    // Format messages for Ollama
+    const messages = [
+      { role: 'system', content: optionsArg.systemMessage },
+      ...optionsArg.messageHistory,
+      { role: 'user', content: optionsArg.userMessage }
+    ];
+
+    // Make API call to Ollama
+    const response = await fetch(`${this.baseUrl}/api/chat`, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify({
+        model: this.model,
+        messages: messages,
+        stream: false
+      }),
+    });
+
+    if (!response.ok) {
+      throw new Error(`Ollama API error: ${response.statusText}`);
+    }
+
+    const result = await response.json();
+    
+    return {
+      role: 'assistant' as const,
+      message: result.message.content,
+    };
+  }
+
+  public async audio(optionsArg: { message: string }): Promise<NodeJS.ReadableStream> {
+    throw new Error('Audio generation is not supported by Ollama.');
+  }
+}