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

public class RunningTrack : MonoBehaviour {

	public static RunningTrack Instance;

	public float spawnY, spawnZ;
	public Transform wallContainer;
	public Wall prefab;

	[Header("At start")]
	public float wallSpeed;
	public float wallSpawnDistance;
	public float maxWallWidth;

	[Header("With time")]
	public float maxWallSpeed;
	public float minWallSpawnDistance;
	public float maxMaxWallWidth;

	
	public bool wallSpeedGrowing, wallSpawnDistanceShrinking, maxWallWidthGrowing;

	public float wallSpeedGrowingSpeed, wallSpawnDistanceShrinkingSpeed, maxWallWidthGrowingSpeed;

	[SerializeField]
	private float currentWallSpeed, currentWallSpawnDistance, currentMaxWallWidth;

	private float spawnTime;

	public float WallSpeed {
		get => currentWallSpeed;
	}
	public float WallSpawnDistance {
		get => currentWallSpawnDistance;
	}
	public float MaxWallWidth {
		get => currentMaxWallWidth;
	}

	private void Awake() {
		Instance = this;
	}

	void Start() {
		ResetTrack();
	}

	
	void Update() {
		spawnTime += Time.deltaTime;
		if (spawnTime > currentWallSpawnDistance / currentWallSpeed) {
			spawnTime = 0;
			Vector3 scale = new Vector3(Random.Range(1f, currentMaxWallWidth), 1, 1);
			float trackW = transform.localScale.x;
			float spawnX = Random.Range((-trackW + scale.x) / 2, (trackW - scale.x) / 2);
			Wall newWall = Instantiate(prefab, new Vector3(spawnX, spawnY, spawnZ), Quaternion.identity, wallContainer);
			newWall.transform.localScale = scale;
			newWall.moveSpeed = currentWallSpeed;
		}

		UpdateStats();
	}

	private void UpdateStats() {
		if (wallSpeedGrowing) {
			currentWallSpeed += wallSpeedGrowingSpeed * Time.deltaTime;
			if (currentWallSpeed > maxWallSpeed) {
				currentWallSpeed = maxWallSpeed;
				wallSpeedGrowing = false;
				wallSpawnDistanceShrinking = true;
				UIControl.Instance.NewMessage("Wall gap size is shrinking...");
			}
		}
		if (wallSpawnDistanceShrinking) {
			currentWallSpawnDistance -= wallSpawnDistanceShrinkingSpeed * Time.deltaTime;
			if (currentWallSpawnDistance < minWallSpawnDistance) {
				currentWallSpawnDistance = minWallSpawnDistance;
				wallSpawnDistanceShrinking = false;
				maxWallWidthGrowing = true;
				UIControl.Instance.NewMessage("Walls are getting wider...");
			}
		}
		if (maxWallWidthGrowing) {
			currentMaxWallWidth += maxWallWidthGrowingSpeed * Time.deltaTime;
			if (currentMaxWallWidth > maxMaxWallWidth) {
				currentMaxWallWidth = maxMaxWallWidth;
				maxWallWidthGrowing = false;
				UIControl.Instance.NewMessage("Max difficulty reached!");
			}
		}
	}

	public void ResetTrack() {
		currentWallSpeed = wallSpeed;
		currentWallSpawnDistance = wallSpawnDistance;
		currentMaxWallWidth = maxWallWidth;

		wallSpeedGrowing = true;
		wallSpawnDistanceShrinking = false;
		maxWallWidthGrowing = false;

		foreach (Wall wall in new ArrayList(wallContainer.GetComponentsInChildren<Wall>())) {
			Destroy(wall.gameObject);
		}

		UIControl.Instance.NewMessage("You are gaining speed...");
	}
}