feat(sharing): add email and message sharing functionality

app/api/shared/[token]/messages/[messageId]/route.ts

@@ -0,0 +1,83 @@
+import { createDb } from "@/lib/db"
+import { emailShares, messages } from "@/lib/schema"
+import { eq, and } from "drizzle-orm"
+import { NextResponse } from "next/server"
+
+export const runtime = "edge"
+
+// 通过分享token获取消息详情
+export async function GET(
+  request: Request,
+  { params }: { params: Promise<{ token: string; messageId: string }> }
+) {
+  const { token, messageId } = await params
+  const db = createDb()
+
+  try {
+    // 验证分享token
+    const share = await db.query.emailShares.findFirst({
+      where: eq(emailShares.token, token),
+      with: {
+        email: true
+      }
+    })
+
+    if (!share) {
+      return NextResponse.json(
+        { error: "Share link not found or expired" },
+        { status: 404 }
+      )
+    }
+
+    // 检查分享是否过期
+    if (share.expiresAt && share.expiresAt < new Date()) {
+      return NextResponse.json(
+        { error: "Share link has expired" },
+        { status: 410 }
+      )
+    }
+
+    // 检查邮箱是否过期
+    if (share.email.expiresAt < new Date()) {
+      return NextResponse.json(
+        { error: "Email has expired" },
+        { status: 410 }
+      )
+    }
+
+    // 获取消息详情
+    const message = await db.query.messages.findFirst({
+      where: and(
+        eq(messages.id, messageId),
+        eq(messages.emailId, share.email.id)
+      )
+    })
+
+    if (!message) {
+      return NextResponse.json(
+        { error: "Message not found" },
+        { status: 404 }
+      )
+    }
+
+    return NextResponse.json({
+      message: {
+        id: message.id,
+        from_address: message.fromAddress,
+        to_address: message.toAddress,
+        subject: message.subject,
+        content: message.content,
+        html: message.html,
+        received_at: message.receivedAt,
+        sent_at: message.sentAt
+      }
+    })
+  } catch (error) {
+    console.error("Failed to fetch shared message:", error)
+    return NextResponse.json(
+      { error: "Failed to fetch message" },
+      { status: 500 }
+    )
+  }
+}
+