using UnityEngine;
using System.Collections.Generic;

public class TerrainSpawner : MonoBehaviour
{
    public GameObject SOLID_BLOCK_PREFAB;
    public Vector2 roomSize;
    public Vector2 roomGenLocation;
    public int CHANCE_UP1, CHANCE_DOWN1;

    public int startGen_offset, end_offset;

    private enum PrevBlock
    {
        WENT_UP,
        WENT_DOWN,
        STAYED
    }

    //next is used to force blocks when they have reached a limit
    private enum NextBlock
    {
        GO_UP,
        GO_DOWN,
        STAY,
    }

    NextBlock next;
    PrevBlock prev;

    private bool BoundsCheck(Vector3 a, Vector3 b)
    {
        return (a.y < b.y - 1 && a.y > b.y - (roomSize.y / 2) + 1);
    }
    private bool BoundsCheck2(Vector3 a, Vector3 b)
    {
        return (a.y > b.y + 1 && a.y < b.y + (roomSize.y / 2) - 1);
    }

    void Start()
    {
        Random.seed = (int)System.DateTime.Now.Ticks;
        if (CHANCE_UP1 + CHANCE_DOWN1 != 100)
        {
            Debug.Log("Percentages must add up to 100%");
            return;
        }
        else if (startGen_offset >= roomSize.x)
        {
            Debug.Log("Your starting offset cannot be more than horizontal roomsize");
            return;
        }
        prev = PrevBlock.STAYED;
        next = NextBlock.STAY;
        GameObject upBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(roomGenLocation.x, roomGenLocation.y + roomSize.y / 2f), Quaternion.identity) as GameObject;
        upBlock.transform.localScale = new Vector3(roomSize.x - 1f, 1f, 1f);
        upBlock.gameObject.name = "UpBlock";
        GameObject downBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(roomGenLocation.x, roomGenLocation.y - roomSize.y / 2f), Quaternion.identity) as GameObject;
        downBlock.transform.localScale = new Vector3(roomSize.x - 1f, 1f, 1f);
        downBlock.gameObject.name = "DownBlock";
        GameObject rightBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(roomGenLocation.x + roomSize.x / 2f, roomGenLocation.y), Quaternion.identity) as GameObject;
        rightBlock.transform.localScale = new Vector3(1f, roomSize.y + 1f, 1f);
        rightBlock.gameObject.name = "RightBlock";
        GameObject leftBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(roomGenLocation.x - roomSize.x / 2f, roomGenLocation.y), Quaternion.identity) as GameObject;
        leftBlock.transform.localScale = new Vector3(1f, roomSize.y + 1f, 1f);
        leftBlock.gameObject.name = "LeftBlock";

        Vector3 prevPos = new Vector3(leftBlock.transform.position.x + startGen_offset, downBlock.transform.position.y + 1);
        prev = PrevBlock.STAYED;
        next = NextBlock.STAY;

        for (; prevPos.x < rightBlock.transform.position.x - end_offset; prevPos.x++)
        {
            for (float b = downBlock.transform.position.y + 1; b < (int)roomGenLocation.y + 1; b++)
            {
                if ((Random.Range(1, 101) < CHANCE_UP1 && BoundsCheck(prevPos, roomGenLocation) && (prev == PrevBlock.STAYED || prev == PrevBlock.WENT_UP))
                    || next == NextBlock.GO_UP)
                {// nextblock goes up by 1
                    GameObject tempBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(prevPos.x, prevPos.y + 1f), Quaternion.identity) as GameObject;
                    prevPos = tempBlock.transform.position;
                    tempBlock.gameObject.name = "wentUp";
                    prev = PrevBlock.WENT_UP;
                    next = NextBlock.STAY;
                    break;
                }
                else if ((Random.Range(1, 101) < CHANCE_DOWN1 && BoundsCheck(prevPos, roomGenLocation) && (prev == PrevBlock.STAYED || prev == PrevBlock.WENT_DOWN))
                    || next == NextBlock.GO_DOWN)
                { // nextblock goes down by 1
                    GameObject tempBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(prevPos.x, prevPos.y - 1f), Quaternion.identity) as GameObject;
                    prevPos = tempBlock.transform.position;
                    tempBlock.gameObject.name = "wentDown";
                    prev = PrevBlock.WENT_DOWN;
                    next = NextBlock.STAY;
                    break;
                }
                else
                {//height stays
                    if (prevPos.y >= roomGenLocation.y - 1) // IF I HIT A LIMIT
                    {
                        next = NextBlock.GO_DOWN;
                    }
                    else if (prevPos.y <= roomGenLocation.y - (roomSize.y / 2) + 1) // IF I HIT A LIMIT
                    {
                        next = NextBlock.GO_UP;
                    }
                    else
                    {
                        prev = PrevBlock.STAYED;
                    }
                    GameObject tempBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(prevPos.x, prevPos.y), Quaternion.identity) as GameObject;
                    tempBlock.gameObject.name = "stayed";
                    prevPos = tempBlock.transform.position;
                    break;
                }
            }
        }

        prevPos = new Vector3(leftBlock.transform.position.x + startGen_offset, upBlock.transform.position.y - 1);
        for (; prevPos.x < rightBlock.transform.position.x - end_offset; prevPos.x++)
        {
            for (float b = downBlock.transform.position.y + 1; b < (int)roomGenLocation.y + 1; b++)
            {
                if ((Random.Range(1, 101) < CHANCE_UP1 && BoundsCheck2(prevPos, roomGenLocation) && (prev == PrevBlock.STAYED || prev == PrevBlock.WENT_UP))
                    || next == NextBlock.GO_UP)
                {// nextblock goes up by 1
                    GameObject tempBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(prevPos.x, prevPos.y + 1f), Quaternion.identity) as GameObject;
                    prevPos = tempBlock.transform.position;
                    tempBlock.gameObject.name = "wentUp";
                    prev = PrevBlock.WENT_UP;
                    next = NextBlock.STAY;
                    break;
                }
                else if ((Random.Range(1, 101) < CHANCE_DOWN1 && BoundsCheck2(prevPos, roomGenLocation) && (prev == PrevBlock.STAYED || prev == PrevBlock.WENT_DOWN))
                    || next == NextBlock.GO_DOWN)
                { // nextblock goes down by 1
                    GameObject tempBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(prevPos.x, prevPos.y - 1f), Quaternion.identity) as GameObject;
                    prevPos = tempBlock.transform.position;
                    tempBlock.gameObject.name = "wentDown";
                    prev = PrevBlock.WENT_DOWN;
                    next = NextBlock.STAY;
                    break;
                }
                else
                {//height stays
                    if (prevPos.y >= upBlock.transform.position.y - 1) // IF I HIT A LIMIT
                    {
                        next = NextBlock.GO_DOWN;
                    }
                    else if (prevPos.y <= roomGenLocation.y + 1) // IF I HIT A LIMIT
                    {
                        next = NextBlock.GO_UP;
                    }
                    else
                    {
                        prev = PrevBlock.STAYED;
                    }
                    GameObject tempBlock = Instantiate(SOLID_BLOCK_PREFAB, new Vector3(prevPos.x, prevPos.y), Quaternion.identity) as GameObject;
                    tempBlock.gameObject.name = "stayed";
                    prevPos = tempBlock.transform.position;
                    break;
                }
            }
        }
    }
}