using UnityEngine;
using System.Collections;

public class CloudCrafter : MonoBehaviour
{
    [Header("Set in Inspector")]
    public int numClouds = 40; // The # of clouds to make
    public GameObject cloudPrefab ; // The prefab for the clouds
    public Vector3 cloudPosMin = new Vector3(-50,-5,10);
    public Vector3 cloudPosMax = new Vector3(150,100,10);
    public float cloudScaleMin = 1; // Max scale of each cloud
    public float cloudScaleMax = 3; // Max scale of each cloud
    public float cloudSpeedMult = 0.5f;
    private GameObject[] cloudInstances;
    void Awake() {
        // Make an array large enough to hold all the Cloud instances
        cloudInstances = new GameObject[numClouds];
        // Find the CloudAnchor parent GameObject
        GameObject anchor = GameObject.Find("CloudAnchor");
        // Iterate through and make Clouds
        GameObject cloud;
        for (int i = 0; i < numClouds; i++) {
            // Make an instance of cloudPrefab
            cloud = Instantiate<GameObject>(cloudPrefab);
            // Position cloud
            Vector3 cPos = Vector3.zero;
            cPos.x = Random.Range(cloudPosMin.x, cloudPosMax.x);
            cPos.y = Random.Range(cloudPosMin.y, cloudPosMax.y);
            // Scale cloud
            float scaleU = Random.value;
            float scaleVal = Mathf.Lerp(cloudScaleMin, cloudScaleMax, scaleU);
            // Smaller clouds (with smaller scaleU) should be nearer the ground 
            cPos.y = Mathf.Lerp(cloudPosMin.y, cPos.y, scaleU);
            // Smaller cloud should be further away
            cPos.z = 100 - 90 * scaleU;
            // Apply these transforms to the cloud
            cloud.transform.position = cPos;
            cloud.transform.localScale = Vector3.one * scaleVal;
            // Make cloud a child of the anchor
            cloud.transform.SetParent(anchor.transform);
            // Add the cloud to cloudInstances
            cloudInstances[i] = cloud;
        }
    }

    // Update is called once per frame
    void Update()
    {
        // Iterate over each cloud that was create
        foreach (GameObject cloud in cloudInstances) {
            // Get the cloud scale and position
            float scaleVal = cloud.transform.localScale.x;
            Vector3 cPos = cloud.transform.position;
            // Move larger clouds faster
            cPos.x -= scaleVal * Time.deltaTime * cloudSpeedMult;
            // If a cloud has moved too far to the left...
            if (cPos.x <= cloudPosMin.x) {
                // Move it to the far right
                cPos.x = cloudPosMax.x;
            }
            // Apply the new position to cloud
            cloud.transform.position = cPos;
        }
    }
}