from __future__ import annotations

from app.exercises.dead_bug.state_machine import DeadBugStateMachine
from app.exercises.dead_bug.types import DeadBugMetrics, DeadBugPhase

class TestDeadBugStateMachine:
    """死虫式状态机单元测试"""

    def _ready_metrics(self) -> DeadBugMetrics:
        """构建准备姿态的度量数据"""
        return DeadBugMetrics(
            left_arm_extended=False, right_arm_extended=False,
            left_leg_extended=False, right_leg_extended=False,
            left_elbow_angle=90, right_elbow_angle=90,
            left_knee_angle=100, right_knee_angle=100,
            feedback=[],
        )

    def _extended_left(self) -> DeadBugMetrics:
        """构建左臂+右腿对角伸展的度量数据"""
        return DeadBugMetrics(
            left_arm_extended=True, right_arm_extended=False,
            left_leg_extended=False, right_leg_extended=True,
            left_elbow_angle=160, right_elbow_angle=90,
            left_knee_angle=90, right_knee_angle=160,
            feedback=[],
        )

    def _both_legs_extended(self) -> DeadBugMetrics:
        """构建双腿同时伸展的非标准姿态"""
        return DeadBugMetrics(
            left_arm_extended=True, right_arm_extended=True,
            left_leg_extended=True, right_leg_extended=True,
            left_elbow_angle=160, right_elbow_angle=160,
            left_knee_angle=160, right_knee_angle=160,
            feedback=[],
        )

    def _arms_extended_ready_legs(self) -> DeadBugMetrics:
        """构建腿已收回但手臂未收回的姿态"""
        return DeadBugMetrics(
            left_arm_extended=True, right_arm_extended=True,
            left_leg_extended=False, right_leg_extended=False,
            left_elbow_angle=160, right_elbow_angle=160,
            left_knee_angle=100, right_knee_angle=100,
            feedback=[],
        )

    def _right_knee_angle(self, angle: float) -> DeadBugMetrics:
        """构建右膝角连续变化但伸展布尔值尚未稳定的姿态"""
        return DeadBugMetrics(
            left_arm_extended=True, right_arm_extended=True,
            left_leg_extended=False, right_leg_extended=False,
            left_elbow_angle=160, right_elbow_angle=160,
            left_knee_angle=90, right_knee_angle=angle,
            feedback=[],
        )

    def test_initial_state(self):
        """测试：状态机初始化后应为READY且计数为0"""
        sm = DeadBugStateMachine()
        assert sm.phase == DeadBugPhase.READY
        assert sm.rep_count == 0

    def test_no_transition_in_ready(self):
        """测试：准备姿态下不触发状态转换"""
        sm = DeadBugStateMachine()
        result = sm.update(self._ready_metrics())
        assert sm.phase == DeadBugPhase.READY
        assert result.rep_count == 0

    def test_confirm_extension(self):
        """测试：连续确认帧数后从READY转换到EXTENDING"""
        sm = DeadBugStateMachine(extension_confirm_frames=2, reset_confirm_frames=2)
        sm.update(self._extended_left())
        assert sm.phase == DeadBugPhase.READY
        sm.update(self._extended_left())
        assert sm.phase == DeadBugPhase.EXTENDING

    def test_confirm_extension_from_knee_angle_trend(self):
        """测试：膝角连续上升时，不依赖单帧伸展布尔值也能确认伸展"""
        sm = DeadBugStateMachine(extension_confirm_frames=2, reset_confirm_frames=2)

        sm.update(self._right_knee_angle(100))
        sm.update(self._right_knee_angle(130))
        assert sm.phase == DeadBugPhase.READY
        sm.update(self._right_knee_angle(145))
        sm.update(self._right_knee_angle(150))

        assert sm.phase == DeadBugPhase.EXTENDING

    def test_full_rep_counts_once_after_strict_reset(self):
        """测试：确认伸展后，只有严格回到准备姿态才计一次"""
        sm = DeadBugStateMachine(extension_confirm_frames=2, reset_confirm_frames=2)

        sm.update(self._extended_left())
        sm.update(self._extended_left())
        assert sm.phase == DeadBugPhase.EXTENDING

        sm.update(self._arms_extended_ready_legs())
        assert sm.rep_count == 0
        assert sm.phase == DeadBugPhase.NEED_RESET

        sm.update(self._ready_metrics())
        result = sm.update(self._ready_metrics())
        assert result.rep_count == 1
        assert sm.phase == DeadBugPhase.READY

        result = sm.update(self._ready_metrics())
        assert result.rep_count == 1

    def test_both_legs_do_not_start_rep(self):
        """测试：双腿同时伸展不进入计数流程"""
        sm = DeadBugStateMachine(extension_confirm_frames=2, reset_confirm_frames=2)
        sm.update(self._both_legs_extended())
        result = sm.update(self._both_legs_extended())

        assert result.rep_count == 0
        assert sm.phase == DeadBugPhase.READY

    def test_no_pose_preserves_confirmed_rep_until_reset(self):
        """测试：已确认伸展后短暂丢姿态，回到准备位仍能完成计数"""
        sm = DeadBugStateMachine(extension_confirm_frames=2, reset_confirm_frames=2)
        sm.update(self._extended_left())
        sm.update(self._extended_left())
        assert sm.phase == DeadBugPhase.EXTENDING

        sm.mark_no_pose()
        sm.update(self._ready_metrics())
        result = sm.update(self._ready_metrics())

        assert result.rep_count == 1
        assert sm.phase == DeadBugPhase.READY