using System;
using System.Collections.Generic;
using UnityEngine.InputSystem;

namespace SepCore.InputModule.Runtime
{
    public sealed class InputModuleDefaultPromptMap : IInputPromptMap
    {
        private readonly InputActionAsset _asset;
        private readonly Dictionary<(InputActionId, InputDeviceKind), InputPrompt> _entries;

        public InputModuleDefaultPromptMap(InputActionAsset asset = null)
        {
            _asset = asset;
            _entries = new Dictionary<(InputActionId, InputDeviceKind), InputPrompt>();
            PopulateKeyboardMouse();
            PopulateGamepad();
            PopulateTouch();
        }

        public bool TryGetPrompt(InputActionId actionId, InputDeviceKind deviceKind, out InputPrompt prompt)
        {
            if (_asset != null && TryDeriveFromOverride(actionId, deviceKind, out prompt))
            {
                return true;
            }

            return _entries.TryGetValue((actionId, deviceKind), out prompt);
        }

        private bool TryDeriveFromOverride(InputActionId actionId, InputDeviceKind deviceKind, out InputPrompt prompt)
        {
            prompt = InputPrompt.None;

            InputAction action = _asset.FindAction(actionId.ToString());
            if (action == null)
            {
                return false;
            }

            string devicePrefix = GetDevicePrefix(deviceKind);
            if (devicePrefix == null)
            {
                return false;
            }

            for (int i = 0; i < action.bindings.Count; i++)
            {
                InputBinding binding = action.bindings[i];

                if (binding.isComposite || binding.isPartOfComposite)
                {
                    continue;
                }

                if (binding.overridePath == null)
                {
                    continue;
                }

                string effectivePath = binding.effectivePath;
                if (effectivePath != null && effectivePath.StartsWith(devicePrefix, StringComparison.OrdinalIgnoreCase))
                {
                    string label = InputControlPath.ToHumanReadableString(effectivePath);
                    prompt = new InputPrompt(label);
                    return true;
                }
            }

            return false;
        }

        private static string GetDevicePrefix(InputDeviceKind deviceKind)
        {
            switch (deviceKind)
            {
                case InputDeviceKind.KeyboardMouse: return "<Keyboard>";
                case InputDeviceKind.Gamepad: return "<Gamepad>";
                case InputDeviceKind.Touch: return "<Touchscreen>";
                default: return null;
            }
        }

        private void PopulateKeyboardMouse()
        {
            Add(InputActionId.Pause, InputDeviceKind.KeyboardMouse, "Esc", "keyboard_esc");
            Add(InputActionId.Navigate, InputDeviceKind.KeyboardMouse, "WASD");
            Add(InputActionId.Confirm, InputDeviceKind.KeyboardMouse, "Enter", "keyboard_enter");
            Add(InputActionId.Cancel, InputDeviceKind.KeyboardMouse, "Esc", "keyboard_esc");
            Add(InputActionId.Move, InputDeviceKind.KeyboardMouse, "移动", "keyboard_w|keyboard_a|keyboard_s|keyboard_d");
            Add(InputActionId.Sprint, InputDeviceKind.KeyboardMouse, "L Shift", "keyboard_shift");
            Add(InputActionId.Interact, InputDeviceKind.KeyboardMouse, "E", "keyboard_e");
        }

        private void PopulateGamepad()
        {
            Add(InputActionId.Pause, InputDeviceKind.Gamepad, "Menu", "gamepad_menu");
            Add(InputActionId.Navigate, InputDeviceKind.Gamepad, "L Stick", "gamepad_ls");
            Add(InputActionId.Confirm, InputDeviceKind.Gamepad, "A", "gamepad_a");
            Add(InputActionId.Cancel, InputDeviceKind.Gamepad, "B", "gamepad_b");
            Add(InputActionId.Move, InputDeviceKind.Gamepad, "移动", "gamepad_ls");
            Add(InputActionId.Sprint, InputDeviceKind.Gamepad, "L3", "gamepad_press_ls");
            Add(InputActionId.Interact, InputDeviceKind.Gamepad, "A", "gamepad_a");
        }

        private void PopulateTouch()
        {
            Add(InputActionId.Pause, InputDeviceKind.Touch, "Pause");
            Add(InputActionId.Navigate, InputDeviceKind.Touch, "Swipe");
            Add(InputActionId.Confirm, InputDeviceKind.Touch, "Tap");
            Add(InputActionId.Cancel, InputDeviceKind.Touch, "Back");
            Add(InputActionId.Move, InputDeviceKind.Touch, "Joystick");
            Add(InputActionId.Interact, InputDeviceKind.Touch, "Tap");
        }

        private void Add(InputActionId actionId, InputDeviceKind deviceKind, string textLabel, string spriteName = null)
        {
            _entries[(actionId, deviceKind)] = new InputPrompt(textLabel, spriteName);
        }
    }
}