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 BattleDeck<BaseCardT> deck;
    private GameObject uiCanvas;
    private GameObject cardPrefab;
    private HandControlsPosition position;

    private List<BaseCardT> hand;
    private List<GameObject> cardsInHandUIs;
    private TeamChoice team;
    private int insightLevel;
    private HandPlayability<BaseCardT> playability;
    private float scale;

    public HandControls(BattleDeck<BaseCardT> deck, GameObject uiCanvas, GameObject cardPrefab,
            HandControlsPosition position, TeamChoice team, int insightLevel,
            HandPlayability<BaseCardT> playability, float scale) {
        this.deck = deck;
        this.uiCanvas = uiCanvas;
        this.cardPrefab = cardPrefab;
        this.position = position;
        this.team = team;
        this.insightLevel = insightLevel;
        this.playability = playability;
        this.scale = scale;

        deck.OnHandPileChanged += this.UpdateState;

        if (playability != null) {
            playability.OnPlayabilityChanged += this.UpdateState;
        }
    }
    
    private Vector3 CalculateHandCardPosition(int index, int count) {
        float SPACING = 0 * this.scale;
        float DELTA = BattleCardPrefabConstants.CARD_WIDTH * this.scale + SPACING;
        
        float x = Screen.width * 0.5f - DELTA / 2 * (count - 1) + DELTA * index;
        float y = (this.position == HandControlsPosition.Bottom
            ? SPACING + BattleCardPrefabConstants.CARD_HEIGHT * this.scale / 2
            : Screen.height - SPACING - BattleCardPrefabConstants.CARD_HEIGHT * this.scale / 2);

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

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

    private void RenderHand() {
        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);});
        }
    }

    private void UpdateState() {
        this.hand = this.deck.GetHandPile().ToList();
        RenderHand();
        UpdateCardPlayability();
    }

    private void UpdateCardPlayability() {
        if (this.hand == null || this.playability == null) {
            return;
        }

        for (int i = 0; i < this.hand.Count; i++) {
            BaseCardT card = this.hand[i];
            CardUI cardUI = this.cardsInHandUIs[i].GetComponent<CardUI>();
            cardUI.Playable = this.playability.IsPlayable(card);
        }
    }
}