feat(API): 添加对话分享 API 路由

- 新增 /api/conversations/[id]/share 路由
  - POST: 创建分享链接
  - GET: 获取分享信息
  - DELETE: 删除分享
- 新增 /api/share/[code] 路由获取分享内容
- 支持选择性消息分享和内容控制

src/app/api/conversations/[id]/share/route.ts

@@ -0,0 +1,203 @@
+/**
+ * 对话分享 API
+ * POST /api/conversations/[id]/share - 创建分享
+ * GET /api/conversations/[id]/share - 获取对话的分享列表
+ */
+
+import { NextRequest, NextResponse } from 'next/server';
+import { db } from '@/drizzle/db';
+import { conversations, sharedConversations } from '@/drizzle/schema';
+import { eq, and } from 'drizzle-orm';
+import { getCurrentUser } from '@/lib/auth';
+import { nanoid } from 'nanoid';
+
+/**
+ * 生成短链接码（8位字母数字）
+ */
+function generateShareCode(): string {
+  return nanoid(8);
+}
+
+/**
+ * 创建分享
+ */
+export async function POST(
+  request: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  try {
+    // 验证用户身份
+    const user = await getCurrentUser();
+    if (!user) {
+      return NextResponse.json({ error: '未登录' }, { status: 401 });
+    }
+
+    const { id: conversationId } = await params;
+
+    // 获取请求体
+    const body = await request.json();
+    const {
+      title,
+      description,
+      includeThinking = true,
+      includeToolCalls = false,
+      includeImages = true,
+      selectedMessageIds = null, // 新增：选择的消息ID，null 表示全部
+    } = body;
+
+    // 验证对话存在且属于当前用户
+    const conversation = await db.query.conversations.findFirst({
+      where: eq(conversations.conversationId, conversationId),
+    });
+
+    if (!conversation) {
+      return NextResponse.json({ error: '对话不存在' }, { status: 404 });
+    }
+
+    if (conversation.userId !== user.userId) {
+      return NextResponse.json({ error: '无权分享此对话' }, { status: 403 });
+    }
+
+    // 生成分享信息
+    const shareId = nanoid();
+    const shareCode = generateShareCode();
+
+    // 创建分享记录
+    await db.insert(sharedConversations).values({
+      shareId,
+      conversationId,
+      userId: user.userId,
+      shareCode,
+      title: title || conversation.title,
+      description,
+      includeThinking,
+      includeToolCalls,
+      includeImages,
+      snapshotAt: new Date(), // 记录快照时间点
+      selectedMessageIds, // 新增：存储选择的消息ID
+    });
+
+    // 构建分享 URL
+    const baseUrl = process.env.NEXT_PUBLIC_APP_URL || 'http://localhost:3000';
+    const shareUrl = `${baseUrl}/share/${shareCode}`;
+
+    return NextResponse.json({
+      shareId,
+      shareCode,
+      shareUrl,
+      title: title || conversation.title,
+    });
+  } catch (error) {
+    console.error('Create share error:', error);
+    return NextResponse.json({ error: '创建分享失败' }, { status: 500 });
+  }
+}
+
+/**
+ * 获取对话的分享列表
+ */
+export async function GET(
+  request: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  try {
+    // 验证用户身份
+    const user = await getCurrentUser();
+    if (!user) {
+      return NextResponse.json({ error: '未登录' }, { status: 401 });
+    }
+
+    const { id: conversationId } = await params;
+
+    // 验证对话存在且属于当前用户
+    const conversation = await db.query.conversations.findFirst({
+      where: eq(conversations.conversationId, conversationId),
+    });
+
+    if (!conversation) {
+      return NextResponse.json({ error: '对话不存在' }, { status: 404 });
+    }
+
+    if (conversation.userId !== user.userId) {
+      return NextResponse.json({ error: '无权访问' }, { status: 403 });
+    }
+
+    // 获取分享列表
+    const shares = await db.query.sharedConversations.findMany({
+      where: and(
+        eq(sharedConversations.conversationId, conversationId),
+        eq(sharedConversations.isActive, true)
+      ),
+      orderBy: (shares, { desc }) => [desc(shares.createdAt)],
+    });
+
+    // 构建分享 URL
+    const baseUrl = process.env.NEXT_PUBLIC_APP_URL || 'http://localhost:3000';
+
+    return NextResponse.json({
+      shares: shares.map((share) => ({
+        shareId: share.shareId,
+        shareCode: share.shareCode,
+        shareUrl: `${baseUrl}/share/${share.shareCode}`,
+        title: share.title,
+        description: share.description,
+        viewCount: share.viewCount,
+        includeThinking: share.includeThinking,
+        includeToolCalls: share.includeToolCalls,
+        includeImages: share.includeImages,
+        createdAt: share.createdAt,
+      })),
+    });
+  } catch (error) {
+    console.error('Get shares error:', error);
+    return NextResponse.json({ error: '获取分享列表失败' }, { status: 500 });
+  }
+}
+
+/**
+ * 删除分享
+ */
+export async function DELETE(
+  request: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  try {
+    // 验证用户身份
+    const user = await getCurrentUser();
+    if (!user) {
+      return NextResponse.json({ error: '未登录' }, { status: 401 });
+    }
+
+    // 从查询参数获取 shareId
+    const searchParams = request.nextUrl.searchParams;
+    const shareId = searchParams.get('shareId');
+
+    if (!shareId) {
+      return NextResponse.json({ error: '缺少 shareId 参数' }, { status: 400 });
+    }
+
+    // 验证分享存在且属于当前用户
+    const share = await db.query.sharedConversations.findFirst({
+      where: eq(sharedConversations.shareId, shareId),
+    });
+
+    if (!share) {
+      return NextResponse.json({ error: '分享不存在' }, { status: 404 });
+    }
+
+    if (share.userId !== user.userId) {
+      return NextResponse.json({ error: '无权删除此分享' }, { status: 403 });
+    }
+
+    // 软删除（设置 isActive 为 false）
+    await db
+      .update(sharedConversations)
+      .set({ isActive: false, updatedAt: new Date() })
+      .where(eq(sharedConversations.shareId, shareId));
+
+    return NextResponse.json({ success: true });
+  } catch (error) {
+    console.error('Delete share error:', error);
+    return NextResponse.json({ error: '删除分享失败' }, { status: 500 });
+  }
+}

src/app/api/share/[code]/route.ts

@@ -0,0 +1,130 @@
+/**
+ * 公开分享内容 API
+ * GET /api/share/[code] - 获取分享的对话内容（无需登录）
+ */
+
+import { NextRequest, NextResponse } from 'next/server';
+import { db } from '@/drizzle/db';
+import { sharedConversations, conversations, messages } from '@/drizzle/schema';
+import { eq, asc, and, lte, inArray } from 'drizzle-orm';
+
+/**
+ * 获取分享的对话内容
+ */
+export async function GET(
+  request: NextRequest,
+  { params }: { params: Promise<{ code: string }> }
+) {
+  try {
+    const { code: shareCode } = await params;
+
+    // 查找分享记录
+    const share = await db.query.sharedConversations.findFirst({
+      where: eq(sharedConversations.shareCode, shareCode),
+    });
+
+    if (!share) {
+      return NextResponse.json({ error: '分享不存在' }, { status: 404 });
+    }
+
+    // 检查分享是否激活
+    if (!share.isActive) {
+      return NextResponse.json({ error: '分享已失效' }, { status: 410 });
+    }
+
+    // 获取对话信息
+    const conversation = await db.query.conversations.findFirst({
+      where: eq(conversations.conversationId, share.conversationId),
+    });
+
+    if (!conversation) {
+      return NextResponse.json({ error: '对话不存在' }, { status: 404 });
+    }
+
+    // 获取消息列表
+    // 优先级：selectedMessageIds > snapshotAt > 全部
+    let messageList;
+
+    if (share.selectedMessageIds && share.selectedMessageIds.length > 0) {
+      // 如果指定了消息ID，按消息ID过滤
+      messageList = await db.query.messages.findMany({
+        where: and(
+          eq(messages.conversationId, share.conversationId),
+          inArray(messages.messageId, share.selectedMessageIds)
+        ),
+        orderBy: [asc(messages.createdAt)],
+      });
+    } else if (share.snapshotAt) {
+      // 否则按快照时间过滤
+      messageList = await db.query.messages.findMany({
+        where: and(
+          eq(messages.conversationId, share.conversationId),
+          lte(messages.createdAt, share.snapshotAt)
+        ),
+        orderBy: [asc(messages.createdAt)],
+      });
+    } else {
+      // 获取全部消息
+      messageList = await db.query.messages.findMany({
+        where: eq(messages.conversationId, share.conversationId),
+        orderBy: [asc(messages.createdAt)],
+      });
+    }
+
+    // 根据分享设置过滤消息内容
+    const filteredMessages = messageList.map((msg) => ({
+      id: msg.messageId,
+      role: msg.role,
+      content: msg.content,
+      // 根据设置决定是否包含思考内容
+      thinkingContent: share.includeThinking ? msg.thinkingContent : null,
+      // 根据设置决定是否包含工具调用
+      toolCalls: share.includeToolCalls ? msg.toolCalls : null,
+      // 根据设置决定是否包含图片
+      images: share.includeImages ? msg.images : null,
+      searchImages: share.includeImages ? msg.searchImages : null,
+      uploadedImages: share.includeImages ? msg.uploadedImages : null,
+      // 使用的工具（简化显示）
+      usedTools: msg.usedTools,
+      // Token 统计
+      inputTokens: msg.inputTokens,
+      outputTokens: msg.outputTokens,
+      // 时间
+      createdAt: msg.createdAt,
+    }));
+
+    // 更新查看次数（异步，不阻塞响应）
+    db.update(sharedConversations)
+      .set({
+        viewCount: (share.viewCount || 0) + 1,
+        updatedAt: new Date(),
+      })
+      .where(eq(sharedConversations.shareId, share.shareId))
+      .then(() => {})
+      .catch((err) => console.error('Update view count error:', err));
+
+    return NextResponse.json({
+      // 分享信息
+      share: {
+        title: share.title,
+        description: share.description,
+        viewCount: (share.viewCount || 0) + 1,
+        createdAt: share.createdAt,
+      },
+      // 对话信息
+      conversation: {
+        id: conversation.conversationId,
+        title: conversation.title,
+        model: conversation.model,
+        messageCount: filteredMessages.length, // 使用快照中的实际消息数量
+        totalTokens: conversation.totalTokens,
+        createdAt: conversation.createdAt,
+      },
+      // 消息列表
+      messages: filteredMessages,
+    });
+  } catch (error) {
+    console.error('Get shared content error:', error);
+    return NextResponse.json({ error: '获取分享内容失败' }, { status: 500 });
+  }
+}