first implementation

frontend/src/stores/chatStore.ts

@@ -0,0 +1,122 @@
+import { defineStore } from 'pinia'
+import { ref } from 'vue'
+import { api } from '@/services/api'
+
+export interface ChatMessage {
+  id: string
+  role: 'USER' | 'ASSISTANT'
+  content: string
+  sources: Array<{ bookTitle: string; page: number | null }>
+  createdAt: string
+}
+
+export interface ChatSession {
+  sessionId: string
+  topicId: string | null
+  createdAt: string
+}
+
+export const useChatStore = defineStore('chat', () => {
+  const session = ref<ChatSession | null>(null)
+  const messages = ref<ChatMessage[]>([])
+  const loading = ref(false)
+  const sending = ref(false)
+  const error = ref<string | null>(null)
+
+  async function createSession(topicId?: string): Promise<boolean> {
+    loading.value = true
+    error.value = null
+    try {
+      const body = topicId ? { topicId } : {}
+      const response = await api.post<ChatSession>('/chat/sessions', body)
+      session.value = response.data
+      messages.value = []
+      return true
+    } catch (err: any) {
+      error.value = err.message
+      return false
+    } finally {
+      loading.value = false
+    }
+  }
+
+  async function loadMessages(): Promise<void> {
+    if (!session.value) return
+    loading.value = true
+    error.value = null
+    try {
+      const response = await api.get<ChatMessage[]>(
+        `/chat/sessions/${session.value.sessionId}/messages`
+      )
+      messages.value = response.data
+    } catch (err: any) {
+      error.value = err.message
+    } finally {
+      loading.value = false
+    }
+  }
+
+  async function sendMessage(content: string): Promise<boolean> {
+    if (!session.value) return false
+    sending.value = true
+    error.value = null
+
+    // Optimistically add user message
+    const tempUserMsg: ChatMessage = {
+      id: crypto.randomUUID(),
+      role: 'USER',
+      content,
+      sources: [],
+      createdAt: new Date().toISOString()
+    }
+    messages.value.push(tempUserMsg)
+
+    try {
+      const response = await api.post<ChatMessage>(
+        `/chat/sessions/${session.value.sessionId}/messages`,
+        { content }
+      )
+      // Replace temp message & add assistant response
+      messages.value = messages.value.filter((m) => m.id !== tempUserMsg.id)
+      // Reload full conversation to stay in sync
+      await loadMessages()
+      return true
+    } catch (err: any) {
+      // Remove optimistic message on failure
+      messages.value = messages.value.filter((m) => m.id !== tempUserMsg.id)
+      error.value = err.message
+      return false
+    } finally {
+      sending.value = false
+    }
+  }
+
+  async function deleteSession(): Promise<boolean> {
+    if (!session.value) return false
+    loading.value = true
+    error.value = null
+    try {
+      await api.delete(`/chat/sessions/${session.value.sessionId}`)
+      session.value = null
+      messages.value = []
+      return true
+    } catch (err: any) {
+      error.value = err.message
+      return false
+    } finally {
+      loading.value = false
+    }
+  }
+
+  return {
+    session,
+    messages,
+    loading,
+    sending,
+    error,
+    createSession,
+    loadMessages,
+    sendMessage,
+    deleteSession
+  }
+})