初始版本 - Metona Ollama Client v1.1.0

chat-db.js

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+/**
+ * ChatDB - IndexedDB 封装层
+ *
+ * 用于持久化聊天历史记录和设置
+ * 使用 IndexedDB 而非 localStorage，原因：
+ * 1. 支持存储更大的数据（如 base64 图片）
+ * 2. 异步操作不阻塞主线程
+ * 3. 支持事务和索引查询
+ */
+
+export class ChatDB {
+    constructor(dbName = 'metona-ollama', version = 1) {
+        this.dbName = dbName;
+        this.version = version;
+        this.db = null;
+    }
+
+    /**
+     * 初始化数据库
+     * 创建 object stores 和索引
+     */
+    async init() {
+        return new Promise((resolve, reject) => {
+            const request = indexedDB.open(this.dbName, this.version);
+
+            request.onerror = () => {
+                console.error('[ChatDB] 数据库打开失败:', request.error);
+                reject(request.error);
+            };
+
+            request.onsuccess = () => {
+                this.db = request.result;
+                console.log('[ChatDB] 数据库已连接');
+                resolve();
+            };
+
+            // 数据库升级/创建回调
+            request.onupgradeneeded = (event) => {
+                const db = event.target.result;
+
+                // 会话存储
+                if (!db.objectStoreNames.contains('sessions')) {
+                    const sessionStore = db.createObjectStore('sessions', { keyPath: 'id' });
+                    sessionStore.createIndex('updatedAt', 'updatedAt', { unique: false });
+                    sessionStore.createIndex('model', 'model', { unique: false });
+                    console.log('[ChatDB] 创建 sessions 存储');
+                }
+
+                // 设置存储
+                if (!db.objectStoreNames.contains('settings')) {
+                    db.createObjectStore('settings', { keyPath: 'key' });
+                    console.log('[ChatDB] 创建 settings 存储');
+                }
+            };
+        });
+    }
+
+    /**
+     * 确保数据库已连接
+     */
+    _ensureDB() {
+        if (!this.db) throw new Error('数据库未初始化，请先调用 init()');
+    }
+
+    /**
+     * 获取事务
+     */
+    _tx(storeName, mode = 'readonly') {
+        this._ensureDB();
+        const tx = this.db.transaction(storeName, mode);
+        return tx.objectStore(storeName);
+    }
+
+    // ═══════════════════════════════════════════════════════════════
+    // 会话 CRUD
+    // ═══════════════════════════════════════════════════════════════
+
+    /** 保存/更新会话 */
+    async saveSession(session) {
+        return new Promise((resolve, reject) => {
+            const store = this._tx('sessions', 'readwrite');
+            const request = store.put(session);
+            request.onsuccess = () => resolve(session.id);
+            request.onerror = () => reject(request.error);
+        });
+    }
+
+    /** 获取单个会话 */
+    async getSession(id) {
+        return new Promise((resolve, reject) => {
+            const store = this._tx('sessions');
+            const request = store.get(id);
+            request.onsuccess = () => resolve(request.result || null);
+            request.onerror = () => reject(request.error);
+        });
+    }
+
+    /** 获取所有会话 */
+    async getAllSessions() {
+        return new Promise((resolve, reject) => {
+            const store = this._tx('sessions');
+            const request = store.getAll();
+            request.onsuccess = () => resolve(request.result || []);
+            request.onerror = () => reject(request.error);
+        });
+    }
+
+    /** 删除会话 */
+    async deleteSession(id) {
+        return new Promise((resolve, reject) => {
+            const store = this._tx('sessions', 'readwrite');
+            const request = store.delete(id);
+            request.onsuccess = () => resolve();
+            request.onerror = () => reject(request.error);
+        });
+    }
+
+    /** 清空所有会话 */
+    async clearAll() {
+        return new Promise((resolve, reject) => {
+            const store = this._tx('sessions', 'readwrite');
+            const request = store.clear();
+            request.onsuccess = () => resolve();
+            request.onerror = () => reject(request.error);
+        });
+    }
+
+    /** 批量保存会话（单事务，原子性） */
+    async importSessions(sessions) {
+        return new Promise((resolve, reject) => {
+            const tx = this.db.transaction('sessions', 'readwrite');
+            const store = tx.objectStore('sessions');
+            let imported = 0;
+            let skipped = 0;
+
+            tx.oncomplete = () => resolve({ imported, skipped });
+            tx.onerror = () => reject(tx.error);
+
+            // 先检查每个 ID 是否已存在，再 put
+            for (const session of sessions) {
+                if (!session.id || !Array.isArray(session.messages)) {
+                    skipped++;
+                    continue;
+                }
+                const getRequest = store.get(session.id);
+                getRequest.onsuccess = () => {
+                    if (getRequest.result) {
+                        skipped++;
+                    } else {
+                        store.put(session);
+                        imported++;
+                    }
+                };
+            }
+        });
+    }
+
+    /** 按时间范围查询会话 */
+    async getSessionsByTimeRange(startTime, endTime) {
+        return new Promise((resolve, reject) => {
+            const store = this._tx('sessions');
+            const index = store.index('updatedAt');
+            const range = IDBKeyRange.bound(startTime, endTime);
+            const request = index.getAll(range);
+            request.onsuccess = () => resolve(request.result || []);
+            request.onerror = () => reject(request.error);
+        });
+    }
+
+    // ═══════════════════════════════════════════════════════════════
+    // 设置 CRUD
+    // ═══════════════════════════════════════════════════════════════
+
+    /** 保存设置 */
+    async saveSetting(key, value) {
+        return new Promise((resolve, reject) => {
+            const store = this._tx('settings', 'readwrite');
+            const request = store.put({ key, value });
+            request.onsuccess = () => resolve();
+            request.onerror = () => reject(request.error);
+        });
+    }
+
+    /** 获取设置 */
+    async getSetting(key, defaultValue = null) {
+        return new Promise((resolve, reject) => {
+            const store = this._tx('settings');
+            const request = store.get(key);
+            request.onsuccess = () => resolve(request.result ? request.result.value : defaultValue);
+            request.onerror = () => reject(request.error);
+        });
+    }
+}