using System.Linq;
using System;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using System.Collections.Generic;
using Solitaire.Graphics;

namespace Solitaire.Entities {
    public class Card: CardPosition {
        const int SelectedOffset = 3;
        public int DefaultX;

        public Sprite Sprite {get; private set;}
        public Sprite BackSprite {get; private set;}
        public Sprite FrontSprite {get; private set;}
        public int Value;
        public bool Hidden {get; private set;}
        private bool Selected;
        public CardPosition parent = null;

        private double lastClicked;

        public void setSprite() {
            if (Hidden) {
                Sprite = BackSprite;
            } else {
                Sprite = FrontSprite;
            }
        }

        public Card(int value, bool hidden, Vector2 position, Texture2D spriteSheet): base(position) {
            Offset = 13;
            Value = value;
            Hidden = hidden;
            if (Hidden) {
                Offset = 8;
            }

            Position = position;
            DefaultX = (int)position.X;

            Stationary = true;

            BackSprite = new Sprite(spriteSheet, 320, 192, 32, 48);
            FrontSprite = new Sprite(
                spriteSheet,
                (value % 11) * 32,
                (value / 11) * 48,
                32,
                48
            );

            setSprite();
        }

        public void NewPosition(Vector2 position) {
            Position = position;
            DefaultX = (int)position.X;
        }

        public void Hide() {
            Hidden = true;
            setSprite();
        }

        public void UnHide() {
            Hidden = false;
            setSprite();
        }

        public override void Draw(SpriteBatch spriteBatch, GameTime gameTime) {
            Sprite.Draw(spriteBatch, Position);
        }

        private bool inRectangle(Vector2 point, Rectangle rectangle) {
            return (
                point.X >= rectangle.Left &&
                point.X <= rectangle.Right &&
                point.Y > rectangle.Top &&
                point.Y < rectangle.Bottom
            );
        }

        public void SetSelected(Vector2 mPosition, bool mHolding) {
            int height = 40;
            if (child != null) {
                height = Offset;
            } else if (Selected) {
                height += SelectedOffset;
            }

            Rectangle spritePosition = new Rectangle(
                (int)Position.X, (int)Position.Y, 32, height
            );
            if ((!Hidden || child == null) && !mHolding && !Following && inRectangle(mPosition, spritePosition) && !Selected && (child == null || !((Card)child).Selected) && (Offset > 0 || child == null)) {
                Selected = true;
            } else if (!inRectangle(mPosition, spritePosition) && Selected) {
                Selected = false;
                if (child != null) {
                    ((Card)child).SetSelected(mPosition, mHolding);
                    if (((Card)child).Selected) {
                        ((Card)child).SetPosition(mPosition);
                    }
                }
                if (parent != null) {
                    if (parent is Card) {
                        ((Card)parent).SetSelected(mPosition, mHolding);
                        if (((Card)parent).Selected) {
                            ((Card)parent).SetPosition(mPosition);
                        }
                    }
                }
            }
        }

        public void SetPosition(Vector2 mPosition) {
            int X;
            int Y;

            if (Following) {
                X = (int)mPosition.X - 16;
                Y = (int)mPosition.Y - 16;
            } else {
                X = (int)parent.Position.X;
                Y = (int)parent.Position.Y + parent.Offset;
            }

            if (Selected && !Following) {
                Y -= SelectedOffset;
            }

            Position = new Vector2(X, Y);

        }

        public void SetStationary(bool stationary) {
            Stationary = stationary;
            if (child != null) {
                ((Card)child).SetStationary(stationary);
            }
        }

        private bool IsCloser(CardPosition other, CardPosition closest) {
            return (
                other.Stationary &&
                other.child == null &&
                (
                    closest == null ||
                    Vector2.Distance(closest.Position, Position) > Vector2.Distance(other.Position, Position)
                ) &&
                ValidPlacement(other)
            );
        }

        private bool ValidPlacement(CardPosition other) {
            return (
                other == parent ||
                (
                    !(other is Card) &&
                    (
                        (
                            !other.TopPile &&
                            (
                                (
                                    Deck && other.Deck
                                ) ||
                                (
                                    !other.Deck &&
                                    Value % 13 == 12
                                )
                            )
                        ) ||
                        (
                            other.TopPile &&
                            Value % 13 == 0
                        )
                    )
                ) ||
                (
                    other is Card &&
                    (
                        (
                            !other.Deck &&
                            (
                                (
                                    other.TopPile &&
                                    Value / 13 == ((Card)other).Value / 13 &&
                                    Value - 1 == ((Card)other).Value
                                ) ||
                                (
                                    (Value % 13 + 1 == ((Card)other).Value % 13) &&
                                    ((Value / 13) % 2 != (((Card)other).Value / 13) % 2)
                                )
                            )
                        ) ||
                        (
                            Deck && other.Deck && !((Card)other).Hidden
                        )
                    )
                )
            );
        }

        public override void Update(GameTime gameTime, Vector2 mPosition, bool mReleased, bool mHolding, List<IGameEntity> entities) {
            SetSelected(mPosition, mHolding);

            if (parent != null && !Following) {
                DrawOrder = parent.DrawOrder + 1;
            } else if (!Following) {
                DrawOrder = 1;
            }

            if (Selected && mReleased && !Following) {
                if (!Hidden) {
                    lastClicked = gameTime.TotalGameTime.TotalSeconds;
                    Following = true;
                    SetStationary(false);
                    Selected = false;
                    DrawOrder = 1000;
                } else {
                    UnHide();
                    if (Deck) {
                        parent.child = null;
                        Selected = false;
                        SolitaireGame.logic.DeckRevealed.Last().child = this;
                        parent = SolitaireGame.logic.DeckRevealed.Last();
                        SolitaireGame.logic.DeckRevealed.Add(this);
                        SolitaireGame.logic.DeckHidden.Remove(this);
                        parent.Offset = 0;
                    }
                }
            } else if (Following && mReleased) {
                CardPosition closest = null;
                CardPosition oldPosition = parent;

                parent.child = null;

                foreach (IGameEntity entity in entities) {
                    if (entity is CardPosition) {
                        if (IsCloser((CardPosition)entity, closest)) {
                            closest = (CardPosition)entity;
                        }
                    }
                }

                if (closest != null && Vector2.Distance(closest.Position, Position) < 50) {
                    if (ValidPlacement(closest)) {
                        Following = false;
                        SetStationary(true);
                        closest.child = this;
                        parent = closest;
                        if (parent is Card && !((Card)parent).Hidden){
                            parent.Offset = 13;
                        }
                        if (parent.TopPile) {
                            TopPile = true;
                            parent.Offset = 0;
                        } else {
                            TopPile = false;
                        }

                        if (Deck && !closest.Deck) {
                            Deck = false;
                            SolitaireGame.logic.DeckRevealed.Remove(this);
                        }

                        if (Deck) {
                            parent.Offset = 0;
                        }
                    }
                } else {
                    Following = false;
                    SetStationary(true);
                    oldPosition.child = this;
                    parent = oldPosition;
                }

                if (gameTime.TotalGameTime.TotalSeconds - lastClicked < 0.3 && parent == oldPosition) {
                    foreach (IGameEntity entity in SolitaireGame.entities) {
                        if (entity is CardPosition && ((CardPosition)entity).TopPile && ((CardPosition)entity).child == null) {
                            if (
                                (entity is Card && ((Card)entity).Value % 13 == Value % 13 - 1 && ((Card)entity).Value / 13 == Value / 13) ||
                                (!(entity is Card) && Value % 13 == 0)
                                ) {
                                parent.child = null;
                                ((CardPosition)entity).child = this;
                                parent = ((CardPosition)entity);
                                TopPile = true;
                                parent.Offset = 0;

                                if (Deck) {
                                    Deck = false;
                                    SolitaireGame.logic.DeckRevealed.Remove(this);
                                }
                                break;
                            }
                        }
                    }
                }
            } else if (Following && (mPosition.X < 0 || mPosition.X > SolitaireGame.gameWidth || mPosition.Y < 0 || mPosition.Y > SolitaireGame.gameHeight)) {
                Following = false;
                SetStationary(true);
            }

            SetPosition(mPosition);
        }
    }
}