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

public enum HandControlsPosition {
    Top,
    Bottom,
}

public class HandControls<BaseCardT> where BaseCardT : BaseCard
{
    public delegate void CardClickedAction(BaseCardT card);
    public event CardClickedAction OnCardClicked;

    private GameObject uiCanvas;
    private GameObject cardPrefab;
    private HandControlsPosition position;

    private List<BaseCardT> hand;
    private List<GameObject> cardsInHandUIs;
    private int insightLevel;

    public HandControls(GameObject uiCanvas, GameObject cardPrefab, HandControlsPosition position,
            int insightLevel) {
        this.uiCanvas = uiCanvas;
        this.cardPrefab = cardPrefab;
        this.position = position;
        this.insightLevel = insightLevel;
    }
    
    public void SetHand(List<BaseCardT> hand) {
        this.hand = hand;
        DrawHand();
    }
    
    private Vector3 CalculateHandCardPosition(int index, int count) {
        const int SPACING = 8;
        const int DELTA = BattleCardPrefabConstants.CARD_WIDTH + SPACING;
        
        float x = Screen.width * 0.5f - DELTA / 2 * (count - 1) + DELTA * index;
        float y = (this.position == HandControlsPosition.Bottom
            ? SPACING + BattleCardPrefabConstants.CARD_HEIGHT / 2
            : Screen.height - SPACING - BattleCardPrefabConstants.CARD_HEIGHT / 2);

        return new Vector3(x, y, 0);
    }

    public int InsightLevel {
        get => this.insightLevel;
        set {
            this.insightLevel = value;
            DrawHand();
        }
    }

    private void DrawHand() {
        if (this.hand == null) {
            return;
        }

        if (this.cardsInHandUIs != null) {
            foreach (GameObject cardInHandUI in this.cardsInHandUIs) {
                GameObject.Destroy(cardInHandUI);
            }
        }

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