using System.Collections;
using AibisDream.Framework;
using AibisDream.Kit;
using UnityEngine;

namespace AibisDream
{
    /// <summary>应用窗口模式并在实际分辨率稳定后发送显示变化通知。</summary>
    public sealed class DisplaySettingsController : Singleton<DisplaySettingsController>
    {
        private Coroutine _applyRoutine;

        public void ApplyWindowMode(string windowMode)
        {
            if (!TryResolveMode(windowMode, out var width, out var height, out var mode))
            {
                Debug.LogWarning($"[DisplaySettingsController] Unknown window mode: {windowMode}");
                return;
            }

            Screen.SetResolution(width, height, mode);

            if (_applyRoutine != null)
            {
                StopCoroutine(_applyRoutine);
            }

            _applyRoutine = StartCoroutine(WaitForResolution(width, height));
        }

        private IEnumerator WaitForResolution(int targetWidth, int targetHeight)
        {
            var deadline = Time.unscaledTime + 1f;
            while ((Screen.width != targetWidth || Screen.height != targetHeight)
                   && Time.unscaledTime < deadline)
            {
                yield return null;
            }

            _applyRoutine = null;
            EnumEventSystem.Global.Send(SettingChangeEvent.DisplayChanged);
        }

        private static bool TryResolveMode(
            string windowMode,
            out int width,
            out int height,
            out FullScreenMode mode)
        {
            switch (windowMode)
            {
                case "FullScreen":
                case "MaximizedWindow":
                    width = Screen.currentResolution.width;
                    height = Screen.currentResolution.height;
                    mode = FullScreenMode.FullScreenWindow;
                    return true;
                case "Windowed":
                    width = 1920;
                    height = 1080;
                    mode = FullScreenMode.Windowed;
                    return true;
                default:
                    width = 0;
                    height = 0;
                    mode = FullScreenMode.Windowed;
                    return false;
            }
        }
    }
}