feat: Implement AI Chat Agent, Email Notifications, and UI enhancements

server/ai.ts

@@ -0,0 +1,147 @@
+import { IStorage } from "./storage";
+import { User } from "../shared/schema";
+
+interface ChatMessage {
+    role: "system" | "user" | "assistant";
+    content: string;
+}
+
+export class AiService {
+    constructor(private storage: IStorage) { }
+
+    async chat(messages: ChatMessage[], user: User, context: string): Promise<string> {
+        const provider = await this.storage.getSystemSettings("ai_provider") || "openai";
+        const apiKey = await this.storage.getSystemSettings("ai_api_key");
+        const model = await this.storage.getSystemSettings("ai_model") || "gpt-4o";
+        const baseUrl = await this.storage.getSystemSettings("ai_base_url");
+
+        if (!apiKey && provider !== "ollama") {
+            throw new Error("AI API Key not configured");
+        }
+
+        const systemPrompt = `You are TaskFlow AI, an intelligent assistant for the TaskFlow application.
+You have access to the user's current tasks and context.
+User Name: ${user.username}
+Current Context:
+${context}
+
+Answer the user's questions based on this context. Be concise, helpful, and friendly.
+If needed, suggest they create tasks or manage their schedule (you cannot perform actions yet, only advise).
+`;
+
+        const fullMessages = [
+            { role: "system", content: systemPrompt },
+            ...messages
+        ];
+
+        try {
+            if (provider === "openai" || provider === "ollama") {
+                return await this.chatOpenAI(provider, apiKey || "", model, baseUrl, fullMessages);
+            } else if (provider === "anthropic") {
+                return await this.chatAnthropic(apiKey || "", model, fullMessages);
+            } else if (provider === "google") {
+                return await this.chatGemini(apiKey || "", model, fullMessages);
+            } else {
+                throw new Error(`Unsupported AI provider: ${provider}`);
+            }
+        } catch (error: any) {
+            console.error("AI Chat Error:", error);
+            throw new Error(`AI Service Error: ${error.message}`);
+        }
+    }
+
+    private async chatOpenAI(provider: string, apiKey: string, model: string, baseUrl: string | undefined, messages: any[]): Promise<string> {
+        const url = baseUrl || (provider === "ollama" ? "http://localhost:11434/v1" : "https://api.openai.com/v1") + "/chat/completions";
+
+        // Clean URL
+        const cleanUrl = url.replace(/([^:]\/)\/+/g, "$1"); // remove double slashes
+
+        const response = await fetch(cleanUrl, {
+            method: "POST",
+            headers: {
+                "Content-Type": "application/json",
+                "Authorization": `Bearer ${apiKey}`,
+            },
+            body: JSON.stringify({
+                model: model,
+                messages: messages,
+                temperature: 0.7,
+            }),
+        });
+
+        if (!response.ok) {
+            const err = await response.text();
+            throw new Error(`OpenAI/Ollama API Error ${response.status}: ${err}`);
+        }
+
+        const data = await response.json();
+        return data.choices[0]?.message?.content || "No response generated.";
+    }
+
+    private async chatAnthropic(apiKey: string, model: string, messages: any[]): Promise<string> {
+        // Anthropic doesn't support "system" role in messages list in the same way, need to extract it
+        const systemMessage = messages.find(m => m.role === "system")?.content || "";
+        const userAssistantMessages = messages.filter(m => m.role !== "system");
+
+        const response = await fetch("https://api.anthropic.com/v1/messages", {
+            method: "POST",
+            headers: {
+                "Content-Type": "application/json",
+                "x-api-key": apiKey,
+                "anthropic-version": "2023-06-01",
+            },
+            body: JSON.stringify({
+                model: model,
+                system: systemMessage,
+                messages: userAssistantMessages,
+                max_tokens: 1024,
+            }),
+        });
+
+        if (!response.ok) {
+            const err = await response.text();
+            throw new Error(`Anthropic API Error ${response.status}: ${err}`);
+        }
+
+        const data = await response.json();
+        return data.content[0]?.text || "No response generated.";
+    }
+
+    private async chatGemini(apiKey: string, model: string, messages: any[]): Promise<string> {
+        // Google Generative AI (Gemini)
+        // POST https://generativelanguage.googleapis.com/v1beta/models/gemini-pro:generateContent?key=YOUR_API_KEY
+
+        // Mapping messages to Gemini format (contents: [{ role, parts: [{ text }] }])
+        // System instruction is supported in v1beta/models/...:generateContent? 
+        // Gemini 1.5 Pro supports systemInstructions.
+        // For simplicity, I'll prepend system prompt to first user message.
+
+        const systemMessage = messages.find(m => m.role === "system")?.content || "";
+        const contentMessages = messages.filter(m => m.role !== "system").map(m => ({
+            role: m.role === "user" ? "user" : "model",
+            parts: [{ text: m.content }]
+        }));
+
+        if (contentMessages.length > 0 && contentMessages[0].role === "user") {
+            contentMessages[0].parts[0].text = `[System Instruction: ${systemMessage}]\n\nWait for user input... User Input: ` + contentMessages[0].parts[0].text;
+        }
+
+        const url = `https://generativelanguage.googleapis.com/v1beta/models/${model}:generateContent?key=${apiKey}`;
+
+        const response = await fetch(url, {
+            method: "POST",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify({
+                contents: contentMessages
+            }),
+        });
+
+        if (!response.ok) {
+            const err = await response.text();
+            throw new Error(`Gemini API Error ${response.status}: ${err}`);
+        }
+
+        const data = await response.json();
+        return data.candidates?.[0]?.content?.parts?.[0]?.text || "No response generated.";
+    }
+}