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

public class BattlePlayerControls : MonoBehaviour
{
    public BattleController battleController;
    public GameObject uiCanvas;
    public GameObject cardPrefab;

    public delegate void CardUsedAction(BaseCard card);
    public event CardUsedAction OnCardUsed;
    public delegate void TurnPassedAction();
    public event TurnPassedAction OnTurnPassed;

    private HeroDeck heroDeck;
    private List<GameObject> cardsInHandUIs;

    public void Init(HeroDeck heroDeck) {
        this.heroDeck = heroDeck;
    }

    // Start is called before the first frame update
    void Start()
    {
        
    }

    // Update is called once per frame
    void Update()
    {
        
    }

    private void SetHand(List<BaseCard> hand) {
        if (this.cardsInHandUIs != null) {
            foreach (GameObject cardInHandUI in this.cardsInHandUIs) {
                Destroy(cardInHandUI);
            }
        }

        this.cardsInHandUIs = new List<GameObject>();
        for (int i = 0; i < hand.Count; i++) {
            BaseCard card = hand[i];
            GameObject cardUI = Instantiate(this.cardPrefab, this.uiCanvas.transform);
            this.cardsInHandUIs.Add(cardUI);
            cardUI.transform.position = CalculateCardPosition(i, hand.Count);
            cardUI.GetComponent<CardUI>().Init(card);
            int cardIndex = i;
            cardUI.GetComponent<Button>().onClick.AddListener(delegate {OnCardClicked(card);});
        }
    }

    private Vector3 CalculateCardPosition(int index, int count) {
        const int CARD_SIZE = 120;
        const int SPACING = 8;
        const int DELTA = CARD_SIZE + SPACING;
        
        return new Vector3(Screen.width * 0.5f - DELTA / 2 * (count - 1) + DELTA * index, 160, 0);
    }

    private void OnCardClicked(BaseCard card) {
        if (!this.waitingForTarget) {
            if (this.battleController.CanUseCard(card)) {
                OnCardUsed(card);
            }
        }
    }

    private bool waitingForTarget = false;
    private BattleParticipant participantClicked = null;

    public IEnumerator ChooseTarget(System.Action<BattleParticipant> targetCallback) {
        this.waitingForTarget = true;
        while (this.participantClicked == null) {
            yield return null;
        }
        this.waitingForTarget = false;
        targetCallback(participantClicked);
        this.participantClicked = null;
        yield break;
    }

    public void OnParticipantSpriteClicked(BattleParticipant paticipant) {
        if (this.waitingForTarget) {
            this.participantClicked = paticipant;
        }
    }

    public void PassTurnButtonClicked() {
        if (!this.waitingForTarget) {
            OnTurnPassed();
        }
    }

    public bool IsTargeting() {
        return this.waitingForTarget;
    }

    public void NotifyHandPileChanged() {
        SetHand(this.heroDeck.GetHandPile());
    }
}