fix: add User-Agent/Referer headers, GET index first for session cookie, handle non-JSON login response

shared/src/commonMain/kotlin/com/bricks/mp/sage/SageClient.kt

@@ -16,9 +16,10 @@ import kotlinx.serialization.json.*
  * Sage 客户端 - 处理登录、Session 管理和 UI 加载
  * 
  * Sage 使用 Cookie Session 认证：
- * 1. POST /rbac/user/userpassword_login.dspy 登录获取 session cookie
+ * 1. GET 首页获取初始 session cookie
- * 2. 后续请求自动携带 cookie
+ * 2. POST /rbac/user/userpassword_login.dspy 登录
- * 3. GET /xxx.ui 获取 JSON 格式的 UI 描述
+ * 3. 后续请求自动携带 cookie
+ * 4. GET /xxx.ui 获取 JSON 格式的 UI 描述
  */
 class SageClient {
 
@@ -54,45 +55,55 @@ class SageClient {
     suspend fun login(username: String, password: String): Boolean = mutex.withLock {
         _loginError.value = null
         try {
+            // Step 1: GET the index page to obtain initial session cookies
+            // Sage requires a valid session cookie before accepting login POST
+            val indexResponse = client.get("$baseUrl/")
+            println("[Sage] GET / status: ${indexResponse.status}")
+
+            // Step 2: POST login
             val url = "$baseUrl/rbac/user/userpassword_login.dspy"
             val encodedUser = java.net.URLEncoder.encode(username, "UTF-8")
             val encodedPass = java.net.URLEncoder.encode(password, "UTF-8")
             val formBody = "username=$encodedUser&passwd=$encodedPass"
 
             val response = client.post(url) {
+                header(HttpHeaders.UserAgent, "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36")
+                header(HttpHeaders.Referrer, "$baseUrl/")
                 contentType(ContentType.Application.FormUrlEncoded)
                 setBody(formBody)
             }
 
             val body = response.bodyAsText()
             println("[Sage] Login response status: ${response.status}")
-            println("[Sage] Login response body: ${body.take(200)}")
+            println("[Sage] Login response body: ${body.take(300)}")
+
+            // Check if response is JSON
+            if (!body.trimStart().startsWith("{")) {
+                // Non-JSON response - likely an error page or auth failure
+                if (response.status.value == 401 || response.status.value == 403) {
+                    _loginError.value = "登录失败: 服务器拒绝请求 (${response.status.value})"
+                } else {
+                    _loginError.value = "登录失败: 服务器返回非JSON响应 (${response.status.value})"
+                }
+                println("[Sage] Non-JSON login response: ${body.take(200)}")
+                return@withLock false
+            }
 
             // Sage 返回 UiMessage 格式: {"widgettype": "Message", "options": {...}}
-            // 或者返回错误: {"widgettype": "Error", "options": {...}}
             val json = try {
                 Json.parseToJsonElement(body).jsonObject
             } catch (e: Exception) {
-                _loginError.value = "登录响应格式错误: ${e.message}"
+                _loginError.value = "登录响应解析错误: ${e.message}"
                 return@withLock false
             }
 
             val widgetType = json["widgettype"]?.jsonPrimitive?.content
 
             if (widgetType == "Message" || widgetType == "UiMessage") {
-                // 检查是否有 session cookie
                 val cookies = cookieStorage.get(URLBuilder(baseUrl).build())
-                if (cookies.isNotEmpty()) {
+                println("[Sage] Login successful, cookies: ${cookies.size}")
-                    println("[Sage] Login successful, got ${cookies.size} cookies")
+                _isLoggedIn.value = true
-                    _isLoggedIn.value = true
+                true
-                    true
-                } else {
-                    // 即使没有 cookie，如果服务器返回成功也算登录成功
-                    // 有些部署可能使用 token 而非 cookie
-                    println("[Sage] Login successful (no cookies)")
-                    _isLoggedIn.value = true
-                    true
-                }
             } else {
                 // 错误消息
                 val options = json["options"]?.jsonObject ?: JsonObject(emptyMap())
@@ -118,7 +129,9 @@ class SageClient {
             val url = if (path.startsWith("http")) path else "$baseUrl/${path.trimStart('/')}"
             println("[Sage] Fetching UI: $url")
 
-            val response = client.get(url)
+            val response = client.get(url) {
+                header(HttpHeaders.UserAgent, "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36")
+            }
             val body = response.bodyAsText()
 
             if (!response.status.isSuccess()) {
@@ -151,6 +164,7 @@ class SageClient {
                     url {
                         params.forEach { (k, v) -> parameters.append(k, v) }
                     }
+                    header(HttpHeaders.UserAgent, "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36")
                     when {
                         jsonBody != null -> {
                             contentType(ContentType.Application.Json)
@@ -169,6 +183,7 @@ class SageClient {
                     url {
                         params.forEach { (k, v) -> parameters.append(k, v) }
                     }
+                    header(HttpHeaders.UserAgent, "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36")
                 }
             }