// eqpalg/test/test_fb_state_machine.cc
#include <eqpalg/test/test_harness.h>
#include <eqpalg/utility/fb_state_machine.h>
#include <chrono>
#include <map>
#include <string>

using namespace std::chrono;

// 测试辅助：构建最小环境
struct FbTestEnv {
  std::map<std::string, double> vars;
  FbStateMachine fsm;
  TimePoint now;

  FbTestEnv(size_t tag_count = 2) {
    // 模拟已初始化的变量状态
    for (size_t i = 0; i < tag_count; i++) {
      std::string idx = std::to_string(i + 1);
      vars["tag" + idx] = 0.0;
      vars["p" + idx] = 0.0;
      vars["now"] = 0;
    }
    now = std::chrono::system_clock::now();
    vars["now"] = duration_cast<milliseconds>(now.time_since_epoch()).count();
  }

  void setTag(int n, double val) {
    std::string idx = std::to_string(n);
    vars["p" + idx] = vars["tag" + idx];  // p = old tag
    vars["tag" + idx] = val;
  }

  void advanceTime(int ms) {
    now += milliseconds(ms);
    vars["now"] = duration_cast<milliseconds>(now.time_since_epoch()).count();
  }

  FbUpdateResult step(bool trigger) {
    return fsm.update(trigger, now, vars, 2);
  }
};

// ==================== 初始状态 ====================

TEST(initial_state_is_idle) {
  FbTestEnv env;
  CHECK(env.fsm.currentState() == FbState::Idle);
  CHECK_EQ(env.fsm.isActive(), false);
}

// ==================== Idle → Started ====================

TEST(idle_to_started_when_triggered) {
  FbTestEnv env;
  auto result = env.step(true);
  CHECK(result.state == FbState::Started);
  CHECK_EQ(env.fsm.isActive(), true);
  CHECK_EQ(result.funVarsNeedReset, false);
}

TEST(idle_stays_idle_when_not_triggered) {
  FbTestEnv env;
  auto result = env.step(false);
  CHECK(result.state == FbState::Idle);
  CHECK_EQ(result.funVarsNeedReset, true);  // 空闲时重置 fun_vars
}

// ==================== Started → InProgress → Done ====================

TEST(started_proceeds_to_done_via_feedback) {
  FbTestEnv env;

  // 首次触发 → Started
  auto r1 = env.step(true);
  CHECK(r1.state == FbState::Started);

  // Started 自动推进到 InProgress（第二次 update）
  auto r2 = env.step(true);
  CHECK(r2.state == FbState::InProgress || r2.state == FbState::Started);
  // 如果第二次还在 Started，第三次一定到 InProgress
  if (r2.state == FbState::Started) {
    r2 = env.step(true);
  }
  CHECK(r2.state == FbState::InProgress);

  // 反馈条件满足 → Done
  bool done = env.fsm.checkFeedback(true, env.now, env.vars);
  CHECK_EQ(done, true);
  CHECK(env.fsm.currentState() == FbState::Idle);  // 自动回到 Idle
}

// ==================== NotHold ====================

TEST(keep_mode_not_hold_when_trigger_lost) {
  FbTestEnv env;
  env.fsm.configure(true, milliseconds(600000));  // keep_mode=true

  // 触发 → Started
  env.step(true);
  // → InProgress
  env.step(true);
  // 触发丢失 → NotHold
  auto r = env.step(false);
  CHECK(r.state == FbState::NotHold);
  CHECK_EQ(r.funVarsNeedReset, true);
}

// ==================== Timeout ====================

TEST(timeout_when_exceeds_limit) {
  FbTestEnv env;
  env.fsm.configure(false, milliseconds(100));  // 100ms timeout

  // 触发 → Started → InProgress
  env.step(true);
  env.step(true);

  // 超时
  env.advanceTime(200);
  auto r = env.step(true);
  CHECK(r.state == FbState::Timeout);
  CHECK_EQ(r.funVarsNeedReset, true);
}

// ==================== 变量快照 ====================

TEST(snapshot_on_action_start) {
  FbTestEnv env;
  env.setTag(1, 3.0);
  env.setTag(2, 7.0);

  env.step(true);  // → Started（快照发生）

  CHECK_FLOAT_EQ(env.vars["s1"], 3.0, 0.001);
  CHECK_FLOAT_EQ(env.vars["s2"], 7.0, 0.001);
  CHECK_FLOAT_EQ(env.vars["time"], 0.0, 0.001);
  CHECK_FLOAT_EQ(env.vars["mv2_tag1"], 0.0, 0.001);
  // stime 应该被设置
  CHECK(env.vars["stime"] > 0);
}

// ==================== 变量累积 ====================

TEST(action_vars_accumulate_in_progress) {
  FbTestEnv env;
  env.setTag(1, 1.0);  // tag1=1
  env.setTag(2, 0.0);

  env.step(true);   // Started
  env.step(true);   // InProgress (累积发生)

  CHECK_EQ(env.vars["mv2_tag1"] >= 1.0, true);   // tag1==1 被计数
  CHECK_FLOAT_EQ(env.vars["mx_tag1"], 1.0, 0.001);
  CHECK_FLOAT_EQ(env.vars["mi_tag2"], 0.0, 0.001);
}

// ==================== forceReset ====================

TEST(force_reset_returns_to_idle) {
  FbTestEnv env;
  env.step(true);  // Started
  CHECK_EQ(env.fsm.isActive(), true);

  env.fsm.forceReset();
  CHECK(env.fsm.currentState() == FbState::Idle);
  CHECK_EQ(env.fsm.isActive(), false);
}

// ==================== 非 keep 模式下触发丢失 ====================

TEST(no_keep_mode_trigger_loss_stays_in_progress) {
  FbTestEnv env;
  env.fsm.configure(false, milliseconds(600000));  // keep_mode=false

  env.step(true);   // Started
  env.step(true);   // InProgress
  auto r = env.step(false);  // 触发丢失但 keep_mode=false
  CHECK(r.state == FbState::InProgress);  // 不退出
}

// ==================== 终端状态自动回归 Idle ====================

TEST(terminal_state_returns_to_idle_next_cycle) {
  FbTestEnv env;
  env.fsm.configure(false, milliseconds(10));

  env.step(true);
  env.step(true);
  env.advanceTime(20);
  auto r = env.step(true);
  CHECK(r.state == FbState::Timeout);

  // 下一周期自动回到 Idle
  auto r2 = env.step(false);
  CHECK(r2.state == FbState::Idle);
}