feat(ai): AI助手聊天记录服务端持久化

- 图片缓存不再二次压缩，用户预览与AI收到的图片质量一致
- 新增 ai_assistant_sessions 表及 AiAssistantSession 模型
- 新增会话 API：session/list、session/save、session/delete
- 前端会话存储从 IndexedDB 切换为服务端 API，图片落盘到 uploads/assistant/{YYYYMM}/{user_id}/
- saveSessionStore 添加防抖，删除会话时同步清理内存缓存

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/Http/Controllers/Api/AssistantController.php

@@ -2,6 +2,7 @@
 
 namespace App\Http\Controllers\Api;
 
+use App\Models\AiAssistantSession;
 use App\Models\User;
 use App\Module\AI;
 use App\Module\Apps;
@@ -155,4 +156,152 @@ class AssistantController extends AbstractController
         }
         return $dotProduct / $denominator;
     }
+
+    /**
+     * 获取会话列表
+     */
+    public function session__list()
+    {
+        $user = User::auth();
+        $sessionKey = trim(Request::input('session_key', 'default'));
+
+        $sessions = AiAssistantSession::where('userid', $user->userid)
+            ->where('session_key', $sessionKey)
+            ->orderByDesc('updated_at')
+            ->get();
+
+        $list = [];
+        foreach ($sessions as $session) {
+            $data = Base::json2array($session->data);
+            $images = Base::json2array($session->images);
+            foreach ($images as $imageId => $path) {
+                $images[$imageId] = Base::fillUrl($path);
+            }
+            $list[] = [
+                'id' => $session->session_id,
+                'title' => $session->title,
+                'responses' => $data,
+                'images' => $images,
+                'sceneKey' => $session->scene_key,
+                'createdAt' => $session->created_at ? $session->created_at->getTimestampMs() : 0,
+                'updatedAt' => $session->updated_at ? $session->updated_at->getTimestampMs() : 0,
+            ];
+        }
+
+        return Base::retSuccess('success', $list);
+    }
+
+    /**
+     * 保存会话
+     */
+    public function session__save()
+    {
+        $user = User::auth();
+        $sessionKey = trim(Request::input('session_key', 'default'));
+        $sessionId = trim(Request::input('session_id', ''));
+        $sceneKey = trim(Request::input('scene_key', ''));
+        $title = trim(Request::input('title', ''));
+        $data = Request::input('data', []);
+        $newImages = Request::input('new_images', []);
+
+        if (empty($sessionId)) {
+            return Base::retError('session_id 不能为空');
+        }
+
+        $newImageUrls = [];
+        if (is_array($newImages)) {
+            $path = 'uploads/assistant/' . date('Ym') . '/' . $user->userid . '/';
+            foreach ($newImages as $img) {
+                $imageId = $img['imageId'] ?? '';
+                $dataUrl = $img['dataUrl'] ?? '';
+                if (empty($imageId) || empty($dataUrl)) {
+                    continue;
+                }
+                $result = Base::image64save([
+                    'image64' => $dataUrl,
+                    'path' => $path,
+                    'autoThumb' => false,
+                ]);
+                if (Base::isSuccess($result)) {
+                    $newImageUrls[$imageId] = $result['data']['path'];
+                }
+            }
+        }
+
+        $session = AiAssistantSession::where('userid', $user->userid)
+            ->where('session_key', $sessionKey)
+            ->where('session_id', $sessionId)
+            ->first();
+
+        $imageMap = $newImageUrls;
+        if ($session) {
+            $existingImages = Base::json2array($session->images);
+            $imageMap = array_merge($existingImages, $newImageUrls);
+        }
+
+        $session = AiAssistantSession::createInstance([
+            'userid' => $user->userid,
+            'session_key' => $sessionKey,
+            'session_id' => $sessionId,
+            'scene_key' => $sceneKey,
+            'title' => mb_substr($title, 0, 255),
+            'data' => Base::array2json(is_array($data) ? $data : []),
+            'images' => Base::array2json($imageMap),
+        ], $session?->id);
+        $session->save();
+
+        // 仅返回本次新增的图片URL
+        $urls = [];
+        foreach ($newImageUrls as $imageId => $path) {
+            $urls[$imageId] = Base::fillUrl($path);
+        }
+
+        return Base::retSuccess('success', [
+            'image_urls' => $urls,
+        ]);
+    }
+
+    /**
+     * 删除会话
+     */
+    public function session__delete()
+    {
+        $user = User::auth();
+        $sessionKey = trim(Request::input('session_key', 'default'));
+        $sessionId = trim(Request::input('session_id', ''));
+        $clearAll = Request::input('clear_all', false);
+
+        $query = AiAssistantSession::where('userid', $user->userid)
+            ->where('session_key', $sessionKey);
+
+        if ($clearAll) {
+            $sessions = $query->get();
+            foreach ($sessions as $session) {
+                $this->deleteSessionImages($session);
+            }
+            $query->delete();
+        } else {
+            if (empty($sessionId)) {
+                return Base::retError('session_id 不能为空');
+            }
+            $session = $query->where('session_id', $sessionId)->first();
+            if ($session) {
+                $this->deleteSessionImages($session);
+                $session->delete();
+            }
+        }
+
+        return Base::retSuccess('success');
+    }
+
+    private function deleteSessionImages(AiAssistantSession $session)
+    {
+        $images = Base::json2array($session->images);
+        foreach ($images as $path) {
+            $fullPath = public_path($path);
+            if (file_exists($fullPath)) {
+                @unlink($fullPath);
+            }
+        }
+    }
 }

app/Models/AiAssistantSession.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace App\Models;
+
+/**
+ * AI 助手会话
+ *
+ * @property int $id
+ * @property int $userid
+ * @property string $session_key
+ * @property string $session_id
+ * @property string $scene_key
+ * @property string $title
+ * @property string|null $data
+ * @property string|null $images
+ * @property \Carbon\Carbon $created_at
+ * @property \Carbon\Carbon $updated_at
+ */
+class AiAssistantSession extends AbstractModel
+{
+    protected $table = 'ai_assistant_sessions';
+}

database/migrations/2026_04_17_000001_create_ai_assistant_sessions_table.php

@@ -0,0 +1,33 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+class CreateAiAssistantSessionsTable extends Migration
+{
+    public function up()
+    {
+        if (Schema::hasTable('ai_assistant_sessions')) {
+            return;
+        }
+        Schema::create('ai_assistant_sessions', function (Blueprint $table) {
+            $table->bigIncrements('id');
+            $table->bigInteger('userid')->default(0)->comment('用户ID');
+            $table->string('session_key', 100)->default('')->comment('场景分类key');
+            $table->string('session_id', 100)->default('')->comment('前端生成的会话ID');
+            $table->string('scene_key', 200)->default('')->comment('具体场景标识');
+            $table->string('title', 255)->default('')->comment('会话标题');
+            $table->longText('data')->nullable()->comment('responses JSON');
+            $table->longText('images')->nullable()->comment('图片映射 {imageId: relativePath}');
+            $table->timestamps();
+            $table->index('userid', 'idx_userid');
+            $table->unique(['userid', 'session_key', 'session_id'], 'uk_user_session');
+        });
+    }
+
+    public function down()
+    {
+        Schema::dropIfExists('ai_assistant_sessions');
+    }
+}

resources/assets/js/components/AIAssistant/index.vue

@@ -322,6 +322,7 @@ export default {
             maxImages: 5,            // 最大图片数量
             imageCacheKeyPrefix: 'aiAssistant.images', // 图片缓存 key 前缀
             imageCache: {},          // 内存中的图片缓存 {imageId: dataUrl}
+            serverImageMap: {},      // 服务端返回的 {imageId: url} 映射
             isDragging: false,       // 是否正在拖放图片
             dragCounter: 0,          // 拖放计数器（处理嵌套元素）
 
@@ -335,6 +336,9 @@ export default {
         this.refreshWelcomePromptsDebounced = debounce(() => {
             this.displayWelcomePrompts = getWelcomePrompts(this.$store, this.$route?.params || {});
         }, 100);
+        this.saveSessionStoreDebounced = debounce(() => {
+            this.saveSessionStore();
+        }, 2000);
     },
     mounted() {
         emitter.on('openAIAssistant', this.onOpenAIAssistant);
@@ -1274,29 +1278,28 @@ export default {
 
         // ==================== 会话管理方法 ====================
 
-        /**
-         * 获取指定场景的缓存 key
-         */
-        getSessionCacheKey(sessionKey) {
-            return `${this.sessionCacheKeyPrefix}_${sessionKey || 'default'}`;
-        },
-
         /**
          * 加载指定场景的会话数据
          */
         async loadSessionStore(sessionKey) {
-            const cacheKey = this.getSessionCacheKey(sessionKey);
             try {
-                const stored = await $A.IDBString(cacheKey);
-                if (stored) {
-                    this.sessionStore = JSON.parse(stored);
-                    if (!Array.isArray(this.sessionStore)) {
-                        this.sessionStore = [];
-                    }
+                const {data} = await this.$store.dispatch("call", {
+                    url: 'assistant/session/list',
+                    data: {session_key: sessionKey},
+                });
+                if (Array.isArray(data)) {
+                    this.sessionStore = data;
+                    // 缓存服务端返回的图片URL映射
+                    data.forEach(session => {
+                        if (session.images) {
+                            Object.assign(this.serverImageMap, session.images);
+                        }
+                    });
                 } else {
                     this.sessionStore = [];
                 }
             } catch (e) {
+                console.warn('[AIAssistant] 加载会话失败:', e);
                 this.sessionStore = [];
             }
             this.sessionStoreLoaded = true;
@@ -1305,12 +1308,42 @@ export default {
         /**
          * 持久化当前场景的会话数据
          */
-        saveSessionStore() {
-            const cacheKey = this.getSessionCacheKey(this.currentSessionKey);
+        async saveSessionStore() {
+            if (!this.currentSessionId) return;
+            const session = this.sessionStore.find(s => s.id === this.currentSessionId);
+            if (!session) return;
+
+            // 收集本次需要上传的新图片（在 imageCache 中有 base64 但 serverImageMap 中没有的）
+            const newImages = [];
+            const imageIds = this.extractImageIdsFromSession(session);
+            for (const imageId of imageIds) {
+                if (!this.serverImageMap[imageId] && this.imageCache[imageId]) {
+                    newImages.push({
+                        imageId,
+                        dataUrl: this.imageCache[imageId],
+                    });
+                }
+            }
+
             try {
-                $A.IDBSave(cacheKey, JSON.stringify(this.sessionStore));
+                const {data} = await this.$store.dispatch("call", {
+                    url: 'assistant/session/save',
+                    method: 'post',
+                    data: {
+                        session_key: this.currentSessionKey,
+                        session_id: session.id,
+                        scene_key: session.sceneKey || '',
+                        title: session.title || '',
+                        data: session.responses || [],
+                        new_images: newImages,
+                    },
+                });
+                // 更新服务端图片映射
+                if (data?.image_urls) {
+                    Object.assign(this.serverImageMap, data.image_urls);
+                }
             } catch (e) {
-                console.warn('[AIAssistant] Failed to save session store:', e);
+                console.warn('[AIAssistant] 保存会话失败:', e);
             }
         },
 
@@ -1448,7 +1481,7 @@ export default {
                 this.sessionStore.splice(this.maxSessionsPerKey);
             }
 
-            this.saveSessionStore();
+            this.saveSessionStoreDebounced();
         },
 
         /**
@@ -1492,11 +1525,16 @@ export default {
             const index = this.sessionStore.findIndex(s => s.id === sessionId);
             if (index > -1) {
                 const session = this.sessionStore[index];
-                // 清理会话相关的图片缓存
                 this.clearSessionImageCache(session);
                 this.sessionStore.splice(index, 1);
-                this.saveSessionStore();
-                // 如果删除的是当前会话，创建新会话
+                this.$store.dispatch("call", {
+                    url: 'assistant/session/delete',
+                    method: 'post',
+                    data: {
+                        session_key: this.currentSessionKey,
+                        session_id: sessionId,
+                    },
+                }).catch(e => console.warn('[AIAssistant] 删除会话失败:', e));
                 if (this.currentSessionId === sessionId) {
                     this.createNewSession(false);
                 }
@@ -1510,13 +1548,18 @@ export default {
             $A.modalConfirm({
                 title: this.$L('清空历史会话'),
                 content: this.$L('确定要清空当前场景的所有历史会话吗？'),
-                onOk: async () => {
-                    // 清理所有会话的图片缓存
-                    for (const session of this.sessionStore) {
-                        await this.clearSessionImageCache(session);
-                    }
+                onOk: () => {
+                    this.serverImageMap = {};
+                    this.imageCache = {};
                     this.sessionStore = [];
-                    this.saveSessionStore();
+                    this.$store.dispatch("call", {
+                        url: 'assistant/session/delete',
+                        method: 'post',
+                        data: {
+                            session_key: this.currentSessionKey,
+                            clear_all: true,
+                        },
+                    }).catch(e => console.warn('[AIAssistant] 清空会话失败:', e));
                     this.createNewSession(false);
                 }
             });
@@ -1929,27 +1972,11 @@ export default {
             return `${timestamp}_${random}`;
         },
 
-        /**
-         * 获取图片缓存 key
-         */
-        getImageCacheKey(imageId) {
-            return `${this.imageCacheKeyPrefix}_${imageId}`;
-        },
-
         /**
          * 保存图片到独立缓存
          */
-        async saveImageToCache(imageId, dataUrl) {
-            const cacheKey = this.getImageCacheKey(imageId);
-            try {
-                // 压缩到 512px 再保存（历史图片不需要高清）
-                const compressedUrl = await this.resizeDataUrl(dataUrl, 512);
-                await $A.IDBSave(cacheKey, compressedUrl);
-                // 同时保存到内存缓存
-                this.imageCache[imageId] = compressedUrl;
-            } catch (e) {
-                console.warn('[AIAssistant] 图片缓存保存失败:', e);
-            }
+        saveImageToCache(imageId, dataUrl) {
+            this.imageCache[imageId] = dataUrl;
         },
 
         /**
@@ -2000,21 +2027,13 @@ export default {
          * 从缓存获取图片
          */
         async getImageFromCache(imageId) {
-            // 先检查内存缓存
+            // 1. 先检查内存缓存
             if (this.imageCache[imageId]) {
                 return this.imageCache[imageId];
             }
-            // 从 IndexedDB 获取
-            const cacheKey = this.getImageCacheKey(imageId);
-            try {
-                const dataUrl = await $A.IDBString(cacheKey);
-                if (dataUrl) {
-                    // 保存到内存缓存
-                    this.imageCache[imageId] = dataUrl;
-                    return dataUrl;
-                }
-            } catch (e) {
-                console.warn('[AIAssistant] 图片缓存读取失败:', e);
+            // 2. 检查服务端URL映射
+            if (this.serverImageMap[imageId]) {
+                return this.serverImageMap[imageId];
             }
             return null;
         },
@@ -2022,14 +2041,9 @@ export default {
         /**
          * 删除单个图片缓存
          */
-        async deleteImageCache(imageId) {
-            const cacheKey = this.getImageCacheKey(imageId);
-            try {
-                await $A.IDBDel(cacheKey);
-                delete this.imageCache[imageId];
-            } catch (e) {
-                console.warn('[AIAssistant] 图片缓存删除失败:', e);
-            }
+        deleteImageCache(imageId) {
+            delete this.imageCache[imageId];
+            delete this.serverImageMap[imageId];
         },
 
         /**
@@ -2052,10 +2066,10 @@ export default {
         /**
          * 清理会话相关的图片缓存
          */
-        async clearSessionImageCache(session) {
+        clearSessionImageCache(session) {
             const imageIds = this.extractImageIdsFromSession(session);
             for (const imageId of imageIds) {
-                await this.deleteImageCache(imageId);
+                this.deleteImageCache(imageId);
             }
         },