using UnityEngine;
using UnityEngine.InputSystem;

namespace HeneGames.Airplane
{
    /// <summary>
    /// Reads flight controls via the Input System (works when the project uses the new Input System).
    /// Falls back to legacy Input when the old backend is enabled.
    /// </summary>
    internal static class SimpleAirplaneInput
    {
        public static float Horizontal => ReadAxis("Horizontal", ReadHorizontalKeyboard);

        public static float Vertical => ReadAxis("Vertical", ReadVerticalKeyboard);

        public static bool YawLeft => IsPressed(Key.Q, KeyCode.Q);

        public static bool YawRight => IsPressed(Key.E, KeyCode.E);

        public static bool Turbo => IsPressed(Key.LeftShift, KeyCode.LeftShift);

        public static bool GetKeyDown(KeyCode keyCode)
        {
            var keyboard = Keyboard.current;
            if (keyboard != null && TryMapKey(keyCode, out Key key))
                return keyboard[key].wasPressedThisFrame;

#if ENABLE_LEGACY_INPUT_MANAGER
            return Input.GetKeyDown(keyCode);
#else
            return false;
#endif
        }

        public static bool GetKey(KeyCode keyCode)
        {
            var keyboard = Keyboard.current;
            if (keyboard != null && TryMapKey(keyCode, out Key key))
                return keyboard[key].isPressed;

#if ENABLE_LEGACY_INPUT_MANAGER
            return Input.GetKey(keyCode);
#else
            return false;
#endif
        }

        private static float ReadAxis(string axisName, System.Func<float> readKeyboard)
        {
            var keyboard = Keyboard.current;
            if (keyboard != null)
            {
                float value = readKeyboard();
                if (value != 0f)
                    return value;
            }

#if ENABLE_LEGACY_INPUT_MANAGER
            return Input.GetAxisRaw(axisName);
#else
            return 0f;
#endif
        }

        private static float ReadHorizontalKeyboard()
        {
            var keyboard = Keyboard.current;
            float value = 0f;
            if (keyboard.aKey.isPressed || keyboard.leftArrowKey.isPressed)
                value -= 1f;
            if (keyboard.dKey.isPressed || keyboard.rightArrowKey.isPressed)
                value += 1f;
            return value;
        }

        private static float ReadVerticalKeyboard()
        {
            var keyboard = Keyboard.current;
            float value = 0f;
            if (keyboard.sKey.isPressed || keyboard.downArrowKey.isPressed)
                value -= 1f;
            if (keyboard.wKey.isPressed || keyboard.upArrowKey.isPressed)
                value += 1f;
            return value;
        }

        private static bool IsPressed(Key inputSystemKey, KeyCode legacyKey)
        {
            var keyboard = Keyboard.current;
            if (keyboard != null && keyboard[inputSystemKey].isPressed)
                return true;

#if ENABLE_LEGACY_INPUT_MANAGER
            return Input.GetKey(legacyKey);
#else
            return false;
#endif
        }

        private static bool TryMapKey(KeyCode keyCode, out Key key)
        {
            switch (keyCode)
            {
                case KeyCode.Space: key = Key.Space; return true;
                case KeyCode.LeftShift: key = Key.LeftShift; return true;
                case KeyCode.RightShift: key = Key.RightShift; return true;
                case KeyCode.Q: key = Key.Q; return true;
                case KeyCode.E: key = Key.E; return true;
                case KeyCode.W: key = Key.W; return true;
                case KeyCode.A: key = Key.A; return true;
                case KeyCode.S: key = Key.S; return true;
                case KeyCode.D: key = Key.D; return true;
                case KeyCode.UpArrow: key = Key.UpArrow; return true;
                case KeyCode.DownArrow: key = Key.DownArrow; return true;
                case KeyCode.LeftArrow: key = Key.LeftArrow; return true;
                case KeyCode.RightArrow: key = Key.RightArrow; return true;
                default:
                    key = Key.None;
                    return false;
            }
        }
    }
}