diff --git a/tests/test_app.cpp b/tests/test_app.cpp
new file mode 100644
index 0000000..8d7d4fd
--- /dev/null
+++ b/tests/test_app.cpp
@@ -0,0 +1,120 @@
+#include <gtest/gtest.h>
+#include "app.hpp"
+#include <chrono>
+#include <sstream>
+#include <iomanip>
+
+using namespace fzkj;
+
+// ============================================================
+// Task::ToString 测试
+// ============================================================
+
+TEST(TaskToStringTest, testTaskToStringNormalInput) {
+    Task task;
+    task.task_id = 123;
+    task.source_event_id = 456;
+    task.description = "Test task description";
+    task.priority = "高";
+    task.criticality = "关键";
+    // 设置已知时间点 (UTC 2023-10-01 12:30:00)
+    std::tm tm = {};
+    tm.tm_year = 2023 - 1900;
+    tm.tm_mon = 10 - 1;
+    tm.tm_mday = 1;
+    tm.tm_hour = 12;
+    tm.tm_min = 30;
+    tm.tm_sec = 0;
+    tm.tm_isdst = 0;
+    std::time_t t = std::mktime(&tm);
+    // mktime 将本地时间转为 time_t，gmtime 再转回 tm，为了确保一致性，我们直接用 time_t 构造
+    // 注意：由于时区差异，这里使用系统时钟的 to_time_t 进行模拟
+    task.created_at = std::chrono::system_clock::from_time_t(t);
+
+    std::string result = task.ToString();
+    EXPECT_NE(result.find("Task{id=123"), std::string::npos);
+    EXPECT_NE(result.find("source_event=456"), std::string::npos);
+    EXPECT_NE(result.find("desc=\"Test task description\""), std::string::npos);
+    EXPECT_NE(result.find("priority=高"), std::string::npos);
+    EXPECT_NE(result.find("criticality=关键"), std::string::npos);
+    EXPECT_NE(result.find("created="), std::string::npos);
+}
+
+TEST(TaskToStringTest, testTaskToStringBoundaryValues) {
+    Task task;
+    task.task_id = 0; // 最小 ID
+    task.source_event_id = 0;
+    task.description = ""; // 空字符串
+    task.priority = "";
+    task.criticality = "";
+    task.created_at = std::chrono::system_clock::from_time_t(0); // Epoch 时间
+
+    std::string result = task.ToString();
+    EXPECT_NE(result.find("Task{id=0"), std::string::npos);
+    EXPECT_NE(result.find("source_event=0"), std::string::npos);
+    EXPECT_NE(result.find("desc=\"\""), std::string::npos);
+    EXPECT_NE(result.find("priority="), std::string::npos);
+    EXPECT_NE(result.find("criticality="), std::string::npos);
+    // Epoch 时间在 UTC 下应为 1970-01-01 00:00:00
+    EXPECT_NE(result.find("1970-01-01 00:00:00"), std::string::npos);
+}
+
+TEST(TaskToStringTest, testTaskToStringSpecialCharacters) {
+    Task task;
+    task.task_id = 999;
+    task.source_event_id = 888;
+    task.description = "Contains \"quotes\" and, commas"; // 包含引号和逗号
+    task.priority = "中";
+    task.criticality = "一般";
+    task.created_at = std::chrono::system_clock::now();
+
+    std::string result = task.ToString();
+    // 验证特殊字符被原样输出，未做转义
+    EXPECT_NE(result.find("desc=\"Contains \"quotes\" and, commas\""), std::string::npos);
+}
+
+// ============================================================
+// BattleSolution::ToString 测试
+// ============================================================
+
+TEST(BattleSolutionToStringTest, testBattleSolutionToStringNormalInput) {
+    BattleSolution sol;
+    sol.solution_id = 100;
+    sol.task_id = 10;
+    sol.name = "Solution Alpha";
+    sol.score = 95.5;
+    sol.is_distributed = true;
+
+    std::string result = sol.ToString();
+    std::ostringstream expected_ss;
+    expected_ss << "BattleSolution{id=100, task_id=10, name=\"Solution Alpha\", score=95.5, distributed=是}";
+    EXPECT_EQ(result, expected_ss.str());
+}
+
+TEST(BattleSolutionToStringTest, testBattleSolutionToStringBoundaryValues) {
+    BattleSolution sol;
+    sol.solution_id = 0; // 最小 ID
+    sol.task_id = 0;
+    sol.name = ""; // 空字符串
+    sol.score = 0.0; // 零分数
+    sol.is_distributed = false; // 未分发
+
+    std::string result = sol.ToString();
+    std::ostringstream expected_ss;
+    expected_ss << "BattleSolution{id=0, task_id=0, name=\"\", score=0, distributed=否}";
+    EXPECT_EQ(result, expected_ss.str());
+}
+
+TEST(BattleSolutionToStringTest, testBattleSolutionToStringSpecialScenario) {
+    BattleSolution sol;
+    sol.solution_id = 2;
+    sol.task_id = 1;
+    sol.name = "Bad Solution";
+    sol.score = -10.5; // 负数分数
+    sol.is_distributed = false;
+
+    std::string result = sol.ToString();
+    std::ostringstream expected_ss;
+    expected_ss << "BattleSolution{id=2, task_id=1, name=\"Bad Solution\", score=-10.5, distributed=否}";
+    EXPECT_EQ(result, expected_ss.str());
+}
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