using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using TMPro;

/// <summary>
/// Provides access to changing the resolution of the game window
/// </summary>
public class ResolutionControl : MonoBehaviour
{
    [SerializeField] private TMP_Dropdown resolutionDropdown;       // Reference to the drop down setting window

    private Resolution[] resolutions;                               // Resolutions that were gathered from the user's system
    private List<Resolution> filteredResolutions;                   // Resolutions that are filtered base on the refresh rate

    private double currentRefreshRate;                              // The current refresh rate value
    private int currentResolutionIndex = 0;                         // The index in the filtered resolutions list that is active

    // Constant player prefs marker for the value within
    private const string Resolution = "Resolution";

    private void Start()
    {
        // Reset options box and gather data
        resolutions             = Screen.resolutions;
        filteredResolutions     = new List<Resolution>();
        resolutionDropdown.ClearOptions();
        currentRefreshRate      = Screen.currentResolution.refreshRateRatio.value;

        // If the value of the refresh rate of the system matches a gathered resolution's refresh rate,
        // it is added to the filtered list
        for (int i = 0; i < resolutions.Length; i++)
        {
            if (resolutions[i].refreshRateRatio.value == currentRefreshRate)
                filteredResolutions.Add(resolutions[i]);
        }

        // Lists all of the options for resolutions for the user's system
        List<string> options = new List<string>();
        for (int i = 0; i < filteredResolutions.Count; i++)
        {
            string resolutionOption = $"{filteredResolutions[i].width}x{filteredResolutions[i].height} {filteredResolutions[i].refreshRateRatio.value}hz";
            options.Add(resolutionOption);

            if (filteredResolutions[i].width == Screen.width && filteredResolutions[i].height == Screen.height)
                currentResolutionIndex = i;
        }

        // Finally gather the player prefs to set the current resolution index value,
        // otherwise a default resolution index is set while initializing the player Resolution
        try
        {
            currentResolutionIndex = int.Parse(PlayerPrefs.GetString(Resolution));
            resolutionDropdown.AddOptions(options);
            resolutionDropdown.value = currentResolutionIndex;
            resolutionDropdown.RefreshShownValue();
        }
        catch
        {
            PlayerPrefs.SetString(Resolution, currentResolutionIndex.ToString());
            resolutionDropdown.AddOptions(options);
            resolutionDropdown.value = currentResolutionIndex;
            resolutionDropdown.RefreshShownValue();
        }
        finally
        {
            PlayerPrefs.Save();
        }
    }
    /// <summary>
    /// Sets the new resolution index value base on the field chosen in the drop down
    /// </summary>
    /// <param name="resolutionIndex">Dynamic Value: The value of the field in the drop down menu</param>
    public void SetResolution(int resolutionIndex)
    {
        // GUI function to indicate the resolution index that should be used now
        Resolution resolution           = filteredResolutions[resolutionIndex];
        Screen.SetResolution(resolution.width, resolution.height, true);
        currentResolutionIndex          = resolutionIndex;

        PlayerPrefs.SetString(Resolution, currentResolutionIndex.ToString());
        PlayerPrefs.Save();
    }
}