using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.SceneManagement;

public class Character : MonoBehaviour
{
	public string nextScene;

    #region Inspector Fields

    [SerializeField]
    private Inventory startingInventory;

	[SerializeField]
	[Tooltip ("Will move to this block at start, else will try and find a block below")]
	private Block CurrentBlock;

	[SerializeField]
	[Tooltip ("Layers to ignore when checking for blocks")]
	private LayerMask Ignore;

    [Tooltip("Current Inventory of the player")]
    public Inventory Inventory;

	#endregion Inspector Fields

	#region Unity Functions

	private void Awake ()
	{
        Inventory.Clone(startingInventory);

		//If no starting block find one below it
		if (CurrentBlock == null)
			Block.isBlockAtPosition (transform.position + Vector3.down / 2, 1, ~Ignore, out CurrentBlock);

		//move to starting block
		transform.position = CurrentBlock.VisualPosition;
	}

	#endregion Unity Functions

	#region Class Implementation

	/// <summary>
	/// Moves one block in specefied direction, Can walk off obstacles
	/// </summary>
	/// <param name="direction">direction to walk</param>
	/// <remarks>Technically is same as JumpLong(1) but kept seperate to avoid confusion</remarks>
	public void Move (Direction direction)
	{
		//setting up variables
		Vector3 position = CurrentBlock.position + direction.ToVector (transform); // position wanted
		Block hit; //output of block detection
		Block moveTo = CurrentBlock; //block we'll actually move to

		//if move is obstucted no where to move
		if (Block.isBlockAtPosition (position + Vector3.up, 1, ~Ignore))
			return;


		//If block at Position is walkable set it to moveTo
		if (Block.isBlockAtPosition (position, 1, ~Ignore, out hit) && hit.isWalkable (~Ignore))
			moveTo = hit;
        //else if block down one is walkable
        else if (Block.isBlockAtPosition (position + Vector3.down, 1, ~Ignore, out hit) && hit.isWalkable (~Ignore))
			moveTo = hit;

		//set current block && move
		CurrentBlock = moveTo;
		transform.position = CurrentBlock.VisualPosition;
	}

	/// <summary>
	/// Upon collision with a floating block, collect its
	/// Upon collision with the end portal, end of level
	/// </summary>
	/// <param name="other">name of collided object</param>
	void OnTriggerEnter (Collider other)
	{
        Collectable collectable = other.GetComponentInChildren<Collectable>();

		if (other != null) {
            collectable.OnCollect(this);
		}
		if (other.gameObject.name == "End Portal") {
			other.GetComponent<Collider> ().enabled = false;
			Debug.Log ("You finished this level!");
			SceneManager.LoadScene (nextScene);
		}
        
	}

	/// <summary>
	/// Rotates to point in specific direction based on current direction
	/// </summary>
	/// <param name="direction">Local direction to point</param>
	public void Rotate (Direction direction)
	{
		transform.forward = direction.ToVector (transform);
	}

	/// <summary>
	/// Jumps in specefied direction, picks between Long Jump and Jumping up
	/// </summary>
	/// <param name="direction">Direction to Jump</param>
	public void Jump (Direction direction)
	{
		//if there is a block infront JumpUp else LongJump
		if (Block.isBlockAtPosition (CurrentBlock.position + direction.ToVector (transform) + Vector3.up, 1, ~Ignore))
			JumpUp (direction);
		else
			JumpLong (direction);
	}

	#endregion Class Implementation

	#region Private Functions

	/// <summary>
	/// Jumps up obstacle of specific height. Jumps as high as possible
	/// </summary>
	/// <param name="direction">Direction of obstacle</param>
	/// <param name="height">max height</param>
	private void JumpUp (Direction direction, int height = 1)
	{
		//setting up variables
		Vector3 position; // position wanted
		Block hit; //output of block detection
		Block moveTo = CurrentBlock; //block we'll actually move to

		//Check blocks in going up then move to the heighest walkable one
		for (int i = 0; i <= height; i++) {
			//next position up the tower
			position = CurrentBlock.position + direction.ToVector (transform) + (Vector3.up * i);

			//if block is walkable set it to last known position
			if (Block.isBlockAtPosition (position, 1, ~Ignore, out hit) && hit.isWalkable (~Ignore))
				moveTo = hit;
		}

		//set current block && move
		CurrentBlock = moveTo;
		transform.position = CurrentBlock.VisualPosition;
	}

	/// <summary>
	/// Long jumps forward a specified distance. Can Jump gaps. Stops at obstruction
	/// </summary>
	/// <param name="direction">Direction to Jump</param>
	/// <param name="Distance">Max distance</param>
	private void JumpLong (Direction direction, int Distance = 2)
	{
		//setting up variables
		Vector3 position; // position wanted
		Block hit; //output of block detection
		Block moveTo = CurrentBlock; //block we'll actually move to

		//Check blocks in front until we hit an obstruction or went the distance
		for (int i = 1; i <= Distance; i++) {
			//Next position to MoveTo
			position = CurrentBlock.position + (direction.ToVector (transform) * i);

			//if jump is obstructed, stop and go to last known block
			if (Block.isBlockAtPosition (position + Vector3.up, 1, ~Ignore))
				break;


			//If block at Position is walkable set it to last known position
			if (Block.isBlockAtPosition (position, 1, ~Ignore, out hit) && hit.isWalkable (~Ignore))
				moveTo = hit;
            //else if block down one is walkable
            else if (Block.isBlockAtPosition (position + Vector3.down, 1, ~Ignore, out hit) && hit.isWalkable (~Ignore))
				moveTo = hit;

		}//end for

		//Set Current Block and move
		CurrentBlock = moveTo;
		transform.position = CurrentBlock.VisualPosition;
	}

	#endregion Private Functions

}