using System.Collections;
using System.Collections.Generic;
using System.Runtime.Serialization.Formatters;
using System;
using UnityEngine;

public class CameraHolder : MonoBehaviour
{
    //camera holder
    public Transform Holder;
    public float currDistance = 5.0f;
    public float xRotate = 250.0f;
    public float yRotate = 120.0f;
    public float yMinLimit = -20f;
    public float yMaxLimit = 80f;
    public float prevDistance;
    private float x = 0.0f;
    private float y = 0.0f;

    [Header("GUI")]
    private float windowDpi;
    public GameObject[] Prefabs;
    private int Prefab;
    private GameObject Instance;
    private float StartColor;
    private float HueColor;
    public Texture HueTexture;

    void Start()
    {
        if (Screen.dpi < 1) windowDpi = 1;
        if (Screen.dpi < 200) windowDpi = 1;
        else windowDpi = Screen.dpi / 200f;
        var angles = transform.eulerAngles;
        x = angles.y;
        y = angles.x;
        Counter(0);
    }

    private void OnGUI()
    {
        if (GUI.Button(new Rect(5 * windowDpi, 5 * windowDpi, 110 * windowDpi, 35 * windowDpi), "Previous effect"))
        {
            Counter(-1);
        }
        if (GUI.Button(new Rect(120 * windowDpi, 5 * windowDpi, 110 * windowDpi, 35 * windowDpi), "Play again"))
        {
            Counter(0);
        }
        if (GUI.Button(new Rect(235 * windowDpi, 5 * windowDpi, 110 * windowDpi, 35 * windowDpi), "Next effect"))
        {
            Counter(+1);
        }

        StartColor = HueColor;
        HueColor = GUI.HorizontalSlider(new Rect(5 * windowDpi, 45 * windowDpi, 340 * windowDpi, 35 * windowDpi), HueColor, 0, 1);
        GUI.DrawTexture(new Rect(5 * windowDpi, 65 * windowDpi, 340 * windowDpi, 15 * windowDpi), HueTexture, ScaleMode.StretchToFill, false, 0);
        if (HueColor != StartColor)
        {
            int i = 0;
            foreach (var ps in particleSystems)
            {
                var main = ps.main;
                Color colorHSV = Color.HSVToRGB(HueColor + H * 0, svList[i].S, svList[i].V);
                main.startColor = new Color(colorHSV.r, colorHSV.g, colorHSV.b, svList[i].A);
                i++;
            }
        }
    }

    private ParticleSystem[] particleSystems = new ParticleSystem[0];
    private List<SVA> svList = new List<SVA>();
    private float H;

    public struct SVA
    {
        public float S;
        public float V;
        public float A;
    }

    void Counter(int count)
    {
        Prefab += count;
        if (Prefab > Prefabs.Length - 1)
        {
            Prefab = 0;
        }
        else if (Prefab < 0)
        {
            Prefab = Prefabs.Length - 1;
        }
        if (Instance != null)
        {
            Destroy(Instance);
        }
        Instance = Instantiate(Prefabs[Prefab]);
        particleSystems = Instance.GetComponentsInChildren<ParticleSystem>(); //Get color from current instance 
        svList.Clear();
        foreach (var ps in particleSystems)
        {
            Color baseColor = ps.main.startColor.color;
            SVA baseSVA = new SVA();
            Color.RGBToHSV(baseColor, out H, out baseSVA.S, out baseSVA.V);
            baseSVA.A = baseColor.a;
            svList.Add(baseSVA);
        }
    }

    void LateUpdate()
    {
        if (currDistance < 2)
        {
            currDistance = 2;
        }
        currDistance -= Input.GetAxis("Mouse ScrollWheel") * 2;
        if (Holder && (Input.GetMouseButton(0) || Input.GetMouseButton(1)))
        {
            var pos = Input.mousePosition;
            float dpiScale = 1;
            if (Screen.dpi < 1) dpiScale = 1;
            if (Screen.dpi < 200) dpiScale = 1;
            else dpiScale = Screen.dpi / 200f;
            if (pos.x < 380 * dpiScale && Screen.height - pos.y < 250 * dpiScale) return;
            Cursor.visible = false;
            Cursor.lockState = CursorLockMode.Locked;
            x += (float)(Input.GetAxis("Mouse X") * xRotate * 0.02);
            y -= (float)(Input.GetAxis("Mouse Y") * yRotate * 0.02);
            y = ClampAngle(y, yMinLimit, yMaxLimit);
            var rotation = Quaternion.Euler(y, x, 0);
            var position = rotation * new Vector3(0, 0, -currDistance) + Holder.position;
            transform.rotation = rotation;
            transform.position = position;
        }
        else
        {
            Cursor.visible = true;
            Cursor.lockState = CursorLockMode.None;
        }

        if (prevDistance != currDistance)
        {
            prevDistance = currDistance;
            var rot = Quaternion.Euler(y, x, 0);
            var po = rot * new Vector3(0, 0, -currDistance) + Holder.position;
            transform.rotation = rot;
            transform.position = po;
        }
    }

    static float ClampAngle(float angle, float min, float max)
    {
        if (angle < -360)
        {
            angle += 360;
        }
        if (angle > 360)
        {
            angle -= 360;
        }
        return Mathf.Clamp(angle, min, max);
    }
}