using System;
using System.Linq;
using AlicizaX.InputGlyph;
using UnityEngine;
using UnityEngine.InputSystem;

public static class GlyphService
{
    /// <summary>
    /// 可选的全局数据库引用。你可以通过场景内的启动组件在 Awake 时赋值，
    /// 或者在调用每个方法时传入 InputGlyphDatabase 参数（见方法签名）。
    /// </summary>
    public static InputGlyphDatabase Database { get; set; }

    public static string GetBindingDisplay(InputAction action, InputGlyphDatabase db = null)
    {
        if (action == null) return string.Empty;
        var control = GetBindingControl(action);
        return control != null ? control.displayName : string.Empty;
    }

    public static string GetBindingControlPath(InputAction action, InputDeviceWatcher.InputDeviceCategory? deviceOverride = null, InputGlyphDatabase db = null)
    {
        if (action == null) return string.Empty;
        var control = GetBindingControl(action, deviceOverride);
        return control != null ? $"{(control.device?.displayName ?? "Unknown")}/{control.displayName}" : string.Empty;
    }

    /// <summary>
    /// 根据当前设备类别（或传入的 deviceOverride）尝试在 action.controls 中找到匹配的 control。
    /// 匹配策略：检查 control.device.displayName 是否包含类别提示词（忽略大小写）。
    /// 如果没有匹配项则返回第一个 control（作为最后的退路），或 null。
    /// </summary>
    public static InputControl GetBindingControl(InputAction action, InputDeviceWatcher.InputDeviceCategory? deviceOverride = null)
    {
        if (action == null) return null;

        var curCategory = deviceOverride ?? InputDeviceWatcher.CurrentCategory;
        var hints = GetDeviceHintsForCategory(curCategory);

        // 首先找匹配 hints 的 control
        foreach (var control in action.controls)
        {
            var deviceName = control.device?.displayName ?? string.Empty;
            if (hints.Any(h => deviceName.IndexOf(h, StringComparison.OrdinalIgnoreCase) >= 0))
            {
                return control;
            }
        }

        // 如果没有匹配，尝试返回第一个 gamepad/keyboard 优先的 control（更健壮）
        if (action.controls.Count > 0)
        {
            // 优先返回 keyboard/mouse 类型（如果当前类别是 keyboard）
            if (curCategory == InputDeviceWatcher.InputDeviceCategory.Keyboard)
            {
                var k = action.controls.FirstOrDefault(c => (c.device?.displayName ?? "").IndexOf("Keyboard", StringComparison.OrdinalIgnoreCase) >= 0)
                        ?? action.controls.First();
                return k;
            }

            return action.controls.First();
        }

        return null;
    }

    static string[] GetDeviceHintsForCategory(InputDeviceWatcher.InputDeviceCategory cat)
    {
        switch (cat)
        {
            case InputDeviceWatcher.InputDeviceCategory.Keyboard:
                return new[] { "Keyboard", "Mouse" };
            case InputDeviceWatcher.InputDeviceCategory.Xbox:
                return new[] { "XInput", "Xbox", "Gamepad" };
            case InputDeviceWatcher.InputDeviceCategory.PlayStation:
                return new[] { "DualShock", "DualSense", "PlayStation", "Gamepad" };
            default:
                return new[] { "Gamepad", "Joystick", "Keyboard", "Mouse" };
        }
    }

    /// <summary>
    /// 尝试根据 controlPath 和设备获取 TMP sprite 标签；如果失败会返回 displayFallback（可直接显示的文字）。
    /// 逻辑：
    /// 1) 使用传入 db 或静态 Database；
    /// 2) 先在指定设备表中查找 entry，找不到则回退到 Keyboard 表；
    /// 3) 如果 table 或 tmpAsset 缺失 或 entry.Sprite 缺失，则用 displayFallback（从 controlPath 提取最后段或控制名）。
    /// </summary>
    public static bool TryGetTMPTagForActionPath(string controlPath, InputDeviceWatcher.InputDeviceCategory device, out string tag, out string displayFallback, InputGlyphDatabase db = null)
    {
        tag = null;
        displayFallback = null;
        db = db ?? Database;
        if (string.IsNullOrEmpty(controlPath) || db == null)
        {
            displayFallback = GetDisplayNameFromControlPath(controlPath);
            return false;
        }

        var entry = db.FindEntryByControlPath(controlPath, device);
        if (entry == null)
        {
            // 设备缺失或没有 entry -> 回退 keyboard
            entry = db.FindEntryByControlPath(controlPath, InputDeviceWatcher.InputDeviceCategory.Keyboard);
        }

        if (entry == null)
        {
            displayFallback = GetDisplayNameFromControlPath(controlPath);
            return false;
        }

        // 查找对应表（优先目标设备，再 keyboard）
        var table = db.GetTable(device) ?? db.GetTable(InputDeviceWatcher.InputDeviceCategory.Keyboard);
        if (table == null || table.tmpAsset == null)
        {
            displayFallback = GetDisplayNameFromControlPath(controlPath);
            return false;
        }

        var sprite = entry.Sprite;
        if (sprite == null)
        {
            displayFallback = GetDisplayNameFromControlPath(controlPath);
            return false;
        }

        var spriteName = sprite.name;
        tag = $"<sprite name=\"{spriteName}\">";
        return true;
    }

    public static bool TryGetUISpriteForActionPath(string controlPath, InputDeviceWatcher.InputDeviceCategory device, out Sprite sprite, InputGlyphDatabase db = null)
    {
        sprite = null;
        db = db ?? Database;
        if (string.IsNullOrEmpty(controlPath) || db == null) return false;

        var entry = db.FindEntryByControlPath(controlPath, device) ?? db.FindEntryByControlPath(controlPath, InputDeviceWatcher.InputDeviceCategory.Keyboard);
        if (entry == null) return false;
        if (entry.Sprite == null) return false;

        sprite = entry.Sprite;
        return true;
    }

    static string GetDisplayNameFromControlPath(string controlPath)
    {
        if (string.IsNullOrEmpty(controlPath)) return string.Empty;
        var parts = controlPath.Split('/');
        var last = parts[parts.Length - 1].Trim(new char[] { '{', '}', '<', '>', '\'', '"' });
        return last;
    }
}