import React, { useEffect, useState } from 'react'
import PACK_OF_CARDS from '../utils/packOfCards'
import shuffleArray from '../utils/shuffleArray'
import io from 'socket.io-client'
import queryString from 'query-string'
import { Redirect } from 'react-router-dom'

//NUMBER CODES FOR ACTION CARDS
//SKIP - 404
//DRAW 2 - 252
//WILD - 300
//DRAW 4 WILD - 600

let socket
const ENDPOINT = 'http://localhost:5000'

const Game = (props) => {
    const data = queryString.parse(props.location.search)

    //initialize socket state
    const [room, setRoom] = useState(data.roomCode)
    const [roomFull, setRoomFull] = useState(false)
    const [users, setUsers] = useState([])
    const [currentUser, setCurrentUser] = useState('')

    useEffect(() => {
        const connectionOptions =  {
            "forceNew" : true,
            "reconnectionAttempts": "Infinity", 
            "timeout" : 10000,                  
            "transports" : ["websocket"]
        }
        socket = io.connect(ENDPOINT, connectionOptions)

        socket.emit('join', {room: room}, (error) => {
            if(error)
                setRoomFull(true)
        })

        //cleanup on component unmount
        return function cleanup() {
            socket.emit('disconnect')
            //shut down connnection instance
            socket.off()
        }
    }, [])

    //initialize game state
    const [gameOver, setGameOver] = useState(true)
    const [winner, setWinner] = useState('')
    const [turn, setTurn] = useState('')
    const [player1Deck, setPlayer1Deck] = useState([])
    const [player2Deck, setPlayer2Deck] = useState([])
    const [currentColor, setCurrentColor] = useState('')
    const [currentNumber, setCurrentNumber] = useState('')
    const [playedCardsPile, setPlayedCardsPile] = useState([])
    const [drawCardPile, setDrawCardPile] = useState([])

    //runs once on component mount
    useEffect(() => {
        //shuffle PACK_OF_CARDS array
        const shuffledCards = shuffleArray(PACK_OF_CARDS)

        //extract first 7 elements to player1Deck
        const player1Deck = shuffledCards.splice(0, 7)

        //extract first 7 elements to player2Deck
        const player2Deck = shuffledCards.splice(0, 7)

        //extract random card from shuffledCards and check if its not an action card
        let startingCardIndex
        while(true) {
            startingCardIndex = Math.floor(Math.random() * 94)
            if(shuffledCards[startingCardIndex]==='skipR' || shuffledCards[startingCardIndex]==='_R' || shuffledCards[startingCardIndex]==='D2R' ||
            shuffledCards[startingCardIndex]==='skipG' || shuffledCards[startingCardIndex]==='_G' || shuffledCards[startingCardIndex]==='D2G' ||
            shuffledCards[startingCardIndex]==='skipB' || shuffledCards[startingCardIndex]==='_B' || shuffledCards[startingCardIndex]==='D2B' ||
            shuffledCards[startingCardIndex]==='skipY' || shuffledCards[startingCardIndex]==='_Y' || shuffledCards[startingCardIndex]==='D2Y' ||
            shuffledCards[startingCardIndex]==='W' || shuffledCards[startingCardIndex]==='D4W') {
                continue;
            }
            else
                break;
        }

        //extract the card from that startingCardIndex into the playedCardsPile
        const playedCardsPile = shuffledCards.splice(startingCardIndex, 1)

        //store all remaining cards into drawCardPile
        const drawCardPile = shuffledCards

        //send initial state to server
        socket.emit('initGameState', {
            gameOver: false,
            turn: 'Player 1',
            player1Deck: [...player1Deck],
            player2Deck: [...player2Deck],
            currentColor: playedCardsPile[0].charAt(1),
            currentNumber: playedCardsPile[0].charAt(0),
            playedCardsPile: [...playedCardsPile],
            drawCardPile: [...drawCardPile]
        })
    }, [])

    useEffect(() => {
        socket.on('initGameState', ({ gameOver, turn, player1Deck, player2Deck, currentColor, currentNumber, playedCardsPile, drawCardPile }) => {
            setGameOver(gameOver)
            setTurn(turn)
            setPlayer1Deck(player1Deck)
            setPlayer2Deck(player2Deck)
            setCurrentColor(currentColor)
            setCurrentNumber(currentNumber)
            setPlayedCardsPile(playedCardsPile)
            setDrawCardPile(drawCardPile)
        })

        socket.on('updateGameState', ({ gameOver, winner, turn, player1Deck, player2Deck, currentColor, currentNumber, playedCardsPile, drawCardPile }) => {
            gameOver && setGameOver(gameOver)
            winner && setWinner(winner)
            turn && setTurn(turn)
            player1Deck && setPlayer1Deck(player1Deck)
            player2Deck && setPlayer2Deck(player2Deck)
            currentColor && setCurrentColor(currentColor)
            currentNumber && setCurrentNumber(currentNumber)
            playedCardsPile && setPlayedCardsPile(playedCardsPile)
            drawCardPile && setDrawCardPile(drawCardPile)
        })

        socket.on("roomData", ({ users }) => {
            setUsers(users)
        })

        socket.on('currentUserData', ({ name }) => {
            setCurrentUser(name)
        })
    }, [])

    //some util functions
    const checkGameOver = (arr) => {
        return arr.length === 1
    }
    
    const checkWinner = (arr, player) => {
        return arr.length === 1 ? player : ''
    }

    const changeBackgroundColor = (id) => {
        const backgroundColorIds = [0, 1, 2, 3, 4]
        const newBackgroundColorIds = backgroundColorIds.filter(item => item!=id)
        const gameDiv = document.querySelector('.Game')
        newBackgroundColorIds.forEach(item => {
            gameDiv.classList.remove(`backgroundColor${item}`)
        })
        gameDiv.classList.add(`backgroundColor${id}`)
    }

    //driver functions
    const onCardPlayedHandler = (played_card) => {
        //extract player who played the card
        const cardPlayedBy = turn
        switch(played_card) {
            //if card played was a number card
            case '0R': case '1R': case '2R': case '3R': case '4R': case '5R': case '6R': case '7R': case '8R': case '9R': case '_R': case '0G': case '1G': case '2G': case '3G': case '4G': case '5G': case '6G': case '7G': case '8G': case '9G': case '_G': case '0B': case '1B': case '2B': case '3B': case '4B': case '5B': case '6B': case '7B': case '8B': case '9B': case '_B': case '0Y': case '1Y': case '2Y': case '3Y': case '4Y': case '5Y': case '6Y': case '7Y': case '8Y': case '9Y': case '_Y': {
                //extract number and color of played card
                const numberOfPlayedCard = played_card.charAt(0)
                const colorOfPlayedCard = played_card.charAt(1)
                //check for color match
                if(currentColor === colorOfPlayedCard) {
                    console.log('colors matched!')
                    //check who played the card and return new state accordingly
                    if(cardPlayedBy === 'Player 1') {
                        //remove the played card from player1's deck and add it to playedCardsPile (immutably)
                        //then update turn, currentColor and currentNumber
                        const removeIndex = player1Deck.indexOf(played_card)
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player1Deck),
                            winner: checkWinner(player1Deck, 'Player 1'),
                            turn: 'Player 2',
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player1Deck: [...player1Deck.slice(0, removeIndex), ...player1Deck.slice(removeIndex + 1)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: numberOfPlayedCard
                        })
                    }
                    else {
                        //remove the played card from player2's deck and add it to playedCardsPile (immutably)
                        //then update turn, currentColor and currentNumber
                        const removeIndex = player2Deck.indexOf(played_card)
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player2Deck),
                            winner: checkWinner(player2Deck, 'Player 2'),
                            turn: 'Player 1',
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player2Deck: [...player2Deck.slice(0, removeIndex), ...player2Deck.slice(removeIndex + 1)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: numberOfPlayedCard
                        })
                    }
                }
                //check for number match
                else if(currentNumber === numberOfPlayedCard) {
                    console.log('numbers matched!')
                    //check who played the card and return new state accordingly
                    if(cardPlayedBy === 'Player 1') {
                        //remove the played card from player1's deck and add it to playedCardsPile (immutably)
                        //then update turn, currentColor and currentNumber
                        const removeIndex = player1Deck.indexOf(played_card)
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player1Deck),
                            winner: checkWinner(player1Deck, 'Player 1'),
                            turn: 'Player 2',
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player1Deck: [...player1Deck.slice(0, removeIndex), ...player1Deck.slice(removeIndex + 1)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: numberOfPlayedCard
                        })
                    }
                    else {
                        //remove the played card from player2's deck and add it to playedCardsPile (immutably)
                        //then update turn, currentColor and currentNumber
                        const removeIndex = player2Deck.indexOf(played_card)
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player2Deck),
                            winner: checkWinner(player2Deck, 'Player 2'),
                            turn: 'Player 1',
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player2Deck: [...player2Deck.slice(0, removeIndex), ...player2Deck.slice(removeIndex + 1)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: numberOfPlayedCard
                        })
                    }
                }
                //if no color or number match, invalid move - do not update state
                else {
                    alert('Invalid Move!')
                }
                break;
            }
            //if card played was a skip card
            case 'skipR': case 'skipG': case 'skipB': case 'skipY': {
                //extract color of played skip card
                const colorOfPlayedCard = played_card.charAt(4)
                //check for color match
                if(currentColor === colorOfPlayedCard) {
                    console.log('colors matched!')
                    //check who played the card and return new state accordingly
                    if(cardPlayedBy === 'Player 1') {
                        //remove the played card from player1's deck and add it to playedCardsPile (immutably)
                        //then update currentColor and currentNumber
                        const removeIndex = player1Deck.indexOf(played_card)
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player1Deck),
                            winner: checkWinner(player1Deck, 'Player 1'),
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player1Deck: [...player1Deck.slice(0, removeIndex), ...player1Deck.slice(removeIndex + 1)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: 404
                        })
                    }
                    else {
                        //remove the played card from player2's deck and add it to playedCardsPile (immutably)
                        //then update currentColor and currentNumber
                        const removeIndex = player2Deck.indexOf(played_card)
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player2Deck),
                            winner: checkWinner(player2Deck, 'Player 2'),
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player2Deck: [...player2Deck.slice(0, removeIndex), ...player2Deck.slice(removeIndex + 1)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: 404
                        })
                    }
                }
                //check for number match - if skip card played on skip card
                else if(currentNumber === 404) {
                    console.log('Numbers matched!')
                    //check who played the card and return new state accordingly
                    if(cardPlayedBy === 'Player 1') {
                        //remove the played card from player1's deck and add it to playedCardsPile (immutably)
                        //then update currentColor and currentNumber - turn will remain same
                        const removeIndex = player1Deck.indexOf(played_card)
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player1Deck),
                            winner: checkWinner(player1Deck, 'Player 1'),
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player1Deck: [...player1Deck.slice(0, removeIndex), ...player1Deck.slice(removeIndex + 1)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: 404
                        })
                    }
                    else {
                        //remove the played card from player2's deck and add it to playedCardsPile (immutably)
                        //then update currentColor and currentNumber - turn will remain same
                        const removeIndex = player2Deck.indexOf(played_card)
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player2Deck),
                            winner: checkWinner(player2Deck, 'Player 2'),
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player2Deck: [...player2Deck.slice(0, removeIndex), ...player2Deck.slice(removeIndex + 1)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: 404
                        })
                    }
                }
                //if no color or number match, invalid move - do not update state
                else {
                    alert('Invalid Move!')
                }
                break;
            }
            //if card played was a draw 2 card
            case 'D2R': case 'D2G': case 'D2B': case 'D2Y': {
                //extract color of played skip card
                const colorOfPlayedCard = played_card.charAt(2)
                //check for color match
                if(currentColor === colorOfPlayedCard) {
                    console.log('colors matched!')
                    //check who played the card and return new state accordingly
                    if(cardPlayedBy === 'Player 1') {
                        //remove the played card from player1's deck and add it to playedCardsPile (immutably)
                        //remove 2 new cards from drawCardPile and add them to player2's deck (immutably)
                        //then update currentColor and currentNumber - turn will remain same
                        const removeIndex = player1Deck.indexOf(played_card)
                        //make a copy of drawCardPile array
                        const copiedDrawCardPileArray = [...drawCardPile]
                        //pull out last two elements from it
                        const drawCard1 = copiedDrawCardPileArray.pop()
                        const drawCard2 = copiedDrawCardPileArray.pop()
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player1Deck),
                            winner: checkWinner(player1Deck, 'Player 1'),
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player1Deck: [...player1Deck.slice(0, removeIndex), ...player1Deck.slice(removeIndex + 1)],
                            player2Deck: [...player2Deck.slice(0, player2Deck.length), drawCard1, drawCard2, ...player2Deck.slice(player2Deck.length)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: 252,
                            drawCardPile: [...copiedDrawCardPileArray]
                        })
                    }
                    else {
                        //remove the played card from player2's deck and add it to playedCardsPile (immutably)
                        //remove 2 new cards from drawCardPile and add them to player1's deck (immutably)
                        //then update currentColor and currentNumber - turn will remain same
                        const removeIndex = player2Deck.indexOf(played_card)
                        //make a copy of drawCardPile array
                        const copiedDrawCardPileArray = [...drawCardPile]
                        //pull out last two elements from it
                        const drawCard1 = copiedDrawCardPileArray.pop()
                        const drawCard2 = copiedDrawCardPileArray.pop()
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player2Deck),
                            winner: checkWinner(player2Deck, 'Player 2'),
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player2Deck: [...player2Deck.slice(0, removeIndex), ...player2Deck.slice(removeIndex + 1)],
                            player1Deck: [...player1Deck.slice(0, player1Deck.length), drawCard1, drawCard2, ...player1Deck.slice(player1Deck.length)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: 252,
                            drawCardPile: [...copiedDrawCardPileArray]
                        })
                    }
                }
                //check for number match - if draw 2 card played on draw 2 card
                else if(currentNumber === 252) {                        
                    console.log('number matched!')
                    //check who played the card and return new state accordingly
                    if(cardPlayedBy === 'Player 1') {
                        //remove the played card from player1's deck and add it to playedCardsPile (immutably)
                        //remove 2 new cards from drawCardPile and add them to player2's deck (immutably)
                        //then update currentColor and currentNumber - turn will remain same
                        const removeIndex = player1Deck.indexOf(played_card)
                        //make a copy of drawCardPile array
                        const copiedDrawCardPileArray = [...drawCardPile]
                        //pull out last two elements from it
                        const drawCard1 = copiedDrawCardPileArray.pop()
                        const drawCard2 = copiedDrawCardPileArray.pop()
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player1Deck),
                            winner: checkWinner(player1Deck, 'Player 1'),
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player1Deck: [...player1Deck.slice(0, removeIndex), ...player1Deck.slice(removeIndex + 1)],
                            player2Deck: [...player2Deck.slice(0, player2Deck.length), drawCard1, drawCard2, ...player2Deck.slice(player2Deck.length)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: 252,
                            drawCardPile: [...copiedDrawCardPileArray]
                        })
                    }
                    else {
                        //remove the played card from player2's deck and add it to playedCardsPile (immutably)
                        //remove 2 new cards from drawCardPile and add them to player1's deck (immutably)
                        //then update currentColor and currentNumber - turn will remain same
                        const removeIndex = player2Deck.indexOf(played_card)
                        //make a copy of drawCardPile array
                        const copiedDrawCardPileArray = [...drawCardPile]
                        //pull out last two elements from it
                        const drawCard1 = copiedDrawCardPileArray.pop()
                        const drawCard2 = copiedDrawCardPileArray.pop()
                        //send new state to server
                        socket.emit('updateGameState', {
                            gameOver: checkGameOver(player2Deck),
                            winner: checkWinner(player2Deck, 'Player 2'),
                            playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                            player2Deck: [...player2Deck.slice(0, removeIndex), ...player2Deck.slice(removeIndex + 1)],
                            player1Deck: [...player1Deck.slice(0, player1Deck.length), drawCard1, drawCard2, ...player1Deck.slice(player1Deck.length)],
                            currentColor: colorOfPlayedCard,
                            currentNumber: 252,
                            drawCardPile: [...copiedDrawCardPileArray]
                        })
                    }
                }
                //if no color or number match, invalid move - do not update state
                else {
                    alert('Invalid Move!')
                }
                break;
            }
            //if card played was a wild card
            case 'W': {
                //check who played the card and return new state accordingly
                if(cardPlayedBy === 'Player 1') {
                    //ask for new color
                    const newColor = prompt('Enter first letter of new color in uppercase (R/G/B/Y)')
                    //remove the played card from player1's deck and add it to playedCardsPile (immutably)
                    const removeIndex = player1Deck.indexOf(played_card)
                    //then update turn, currentColor and currentNumber
                    //send new state to server
                    socket.emit('updateGameState', {
                        gameOver: checkGameOver(player1Deck),
                        winner: checkWinner(player1Deck, 'Player 1'),
                        turn: 'Player 2',
                        playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                        player1Deck: [...player1Deck.slice(0, removeIndex), ...player1Deck.slice(removeIndex + 1)],
                        currentColor: newColor,
                        currentNumber: 300
                    })
                }
                else {
                    //ask for new color
                    const newColor = prompt('Enter first letter of new color in uppercase (R/G/B/Y)')
                    //remove the played card from player2's deck and add it to playedCardsPile (immutably)
                    const removeIndex = player2Deck.indexOf(played_card)
                    //then update turn, currentColor and currentNumber
                    socket.emit('updateGameState', {
                        gameOver: checkGameOver(player2Deck),
                        winner: checkWinner(player2Deck, 'Player 2'),
                        turn: 'Player 2',
                        playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                        player2Deck: [...player2Deck.slice(0, removeIndex), ...player2Deck.slice(removeIndex + 1)],
                        currentColor: newColor,
                        currentNumber: 300
                    })
                }
                break;
            }
            //if card played was a draw four wild card
            case 'D4W': {
                //check who played the card and return new state accordingly
                if(cardPlayedBy === 'Player 1') {
                    //ask for new color
                    const newColor = prompt('Enter first letter of new color in uppercase (R/G/B/Y)')
                    //remove the played card from player1's deck and add it to playedCardsPile (immutably)
                    const removeIndex = player1Deck.indexOf(played_card)
                    //remove 2 new cards from drawCardPile and add them to player2's deck (immutably)
                    //make a copy of drawCardPile array
                    const copiedDrawCardPileArray = [...drawCardPile]
                    //pull out last four elements from it
                    const drawCard1 = copiedDrawCardPileArray.pop()
                    const drawCard2 = copiedDrawCardPileArray.pop()
                    const drawCard3 = copiedDrawCardPileArray.pop()
                    const drawCard4 = copiedDrawCardPileArray.pop()
                    //then update currentColor and currentNumber - turn will remain same
                    //send new state to server
                    socket.emit('updateGameState', {
                        gameOver: checkGameOver(player1Deck),
                        winner: checkWinner(player1Deck, 'Player 1'),
                        playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                        player1Deck: [...player1Deck.slice(0, removeIndex), ...player1Deck.slice(removeIndex + 1)],
                        player2Deck: [...player2Deck.slice(0, player2Deck.length), drawCard1, drawCard2, drawCard3, drawCard4, ...player2Deck.slice(player2Deck.length)],
                        currentColor: newColor,
                        currentNumber: 600,
                        drawCardPile: [...copiedDrawCardPileArray]
                    })
                }
                else {
                    //ask for new color
                    const newColor = prompt('Enter first letter of new color in uppercase (R/G/B/Y)')
                    //remove the played card from player2's deck and add it to playedCardsPile (immutably)
                    const removeIndex = player2Deck.indexOf(played_card)
                    //remove 2 new cards from drawCardPile and add them to player1's deck (immutably)
                    //make a copy of drawCardPile array
                    const copiedDrawCardPileArray = [...drawCardPile]
                    //pull out last four elements from it
                    const drawCard1 = copiedDrawCardPileArray.pop()
                    const drawCard2 = copiedDrawCardPileArray.pop()
                    const drawCard3 = copiedDrawCardPileArray.pop()
                    const drawCard4 = copiedDrawCardPileArray.pop()
                    //then update currentColor and currentNumber - turn will remain same
                    //send new state to server
                    socket.emit('updateGameState', {
                        gameOver: checkGameOver(player2Deck),
                        winner: checkWinner(player2Deck, 'Player 2'),
                        playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), played_card, ...playedCardsPile.slice(playedCardsPile.length)],
                        player2Deck: [...player2Deck.slice(0, removeIndex), ...player2Deck.slice(removeIndex + 1)],
                        player1Deck: [...player1Deck.slice(0, player1Deck.length), drawCard1, drawCard2, drawCard3, drawCard4, ...player1Deck.slice(player1Deck.length)],
                        currentColor: newColor,
                        currentNumber: 600,
                        drawCardPile: [...copiedDrawCardPileArray]
                    })
                }
            }
            break;
        }
    }
    
    const onCardDrawnHandler = () => {
        //extract player who drew the card
        const cardDrawnBy = turn
        //check who drew the card and return new state accordingly
        if(cardDrawnBy === 'Player 1') {
            //remove 1 new card from drawCardPile and add it to player1's deck (immutably)
            //make a copy of drawCardPile array
            const copiedDrawCardPileArray = [...drawCardPile]
            //pull out last element from it
            const drawCard = copiedDrawCardPileArray.pop()
            //extract number and color of drawn card
            const colorOfDrawnCard = drawCard.charAt(drawCard.length - 1)
            let numberOfDrawnCard = drawCard.charAt(0)
            if(colorOfDrawnCard === currentColor && (drawCard === 'skipR' || drawCard === 'skipG' || drawCard === 'skipB' || drawCard === 'skipY')) {
                alert(`You drew ${drawCard}. It was played for you.`)
                //send new state to server
                socket.emit('updateGameState', {
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    currentColor: colorOfDrawnCard,
                    currentNumber: 404,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            else if(colorOfDrawnCard === currentColor && (drawCard === 'D2R' || drawCard === 'D2G' || drawCard === 'D2B' || drawCard === 'D2Y')) {
                alert(`You drew ${drawCard}. It was played for you.`)
                //remove 2 new cards from drawCardPile and add them to player2's deck (immutably)
                //make a copy of drawCardPile array
                const copiedDrawCardPileArray = [...drawCardPile]
                //pull out last two elements from it
                const drawCard1 = copiedDrawCardPileArray.pop()
                const drawCard2 = copiedDrawCardPileArray.pop()
                //send new state to server
                socket.emit('updateGameState', {
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    player2Deck: [...player2Deck.slice(0, player2Deck.length), drawCard1, drawCard2, ...player2Deck.slice(player2Deck.length)],
                    currentColor: colorOfDrawnCard,
                    currentNumber: 252,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            else if(drawCard === 'W') {
                alert(`You drew ${drawCard}. It was played for you.`)
                //ask for new color
                const newColor = prompt('Enter first letter of new color in uppercase (R/G/B/Y)')
                //send new state to server
                socket.emit('updateGameState', {
                    turn: 'Player 2',
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    currentColor: newColor,
                    currentNumber: 300,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            else if(drawCard === 'D4W') {
                alert(`You drew ${drawCard}. It was played for you.`)
                //ask for new color
                const newColor = prompt('Enter first letter of new color in uppercase (R/G/B/Y)')
                //remove 2 new cards from drawCardPile and add them to player2's deck (immutably)
                //make a copy of drawCardPile array
                const copiedDrawCardPileArray = [...drawCardPile]
                //pull out last four elements from it
                const drawCard1 = copiedDrawCardPileArray.pop()
                const drawCard2 = copiedDrawCardPileArray.pop()
                const drawCard3 = copiedDrawCardPileArray.pop()
                const drawCard4 = copiedDrawCardPileArray.pop()
                //send new state to server
                socket.emit('updateGameState', {
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    player2Deck: [...player2Deck.slice(0, player2Deck.length), drawCard1, drawCard2, drawCard3, drawCard4, ...player2Deck.slice(player2Deck.length)],
                    currentColor: newColor,
                    currentNumber: 600,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            //if not action card - check if drawn card is playable
            else if(numberOfDrawnCard === currentNumber || colorOfDrawnCard === currentColor) {
                alert(`You drew ${drawCard}. It was played for you.`)
                //send new state to server
                socket.emit('updateGameState', {
                    turn: 'Player 2',
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    currentColor: colorOfDrawnCard,
                    currentNumber: numberOfDrawnCard,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            //else add the drawn card to player1's deck
            else {
                alert(`You drew ${drawCard}.`)
                //send new state to server
                socket.emit('updateGameState', {
                    turn: 'Player 2',
                    player1Deck: [...player1Deck.slice(0, player1Deck.length), drawCard, ...player1Deck.slice(player1Deck.length)],
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
        }
        else {
            //remove 1 new card from drawCardPile and add it to player2's deck (immutably)
            //make a copy of drawCardPile array
            const copiedDrawCardPileArray = [...drawCardPile]
            //pull out last element from it
            const drawCard = copiedDrawCardPileArray.pop()
            //extract number and color of drawn card
            const colorOfDrawnCard = drawCard.charAt(drawCard.length - 1)
            let numberOfDrawnCard = drawCard.charAt(0)
            if(colorOfDrawnCard === currentColor && (drawCard === 'skipR' || drawCard === 'skipG' || drawCard === 'skipB' || drawCard === 'skipY')) {
                alert(`You drew ${drawCard}. It was played for you.`)
                //send new state to server
                socket.emit('updateGameState', {
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    currentColor: colorOfDrawnCard,
                    currentNumber: 404,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            else if(colorOfDrawnCard === currentColor && (drawCard === 'D2R' || drawCard === 'D2G' || drawCard === 'D2B' || drawCard === 'D2Y')) {
                alert(`You drew ${drawCard}. It was played for you.`)
                //remove 2 new cards from drawCardPile and add them to player1's deck (immutably)
                //make a copy of drawCardPile array
                const copiedDrawCardPileArray = [...drawCardPile]
                //pull out last two elements from it
                const drawCard1 = copiedDrawCardPileArray.pop()
                const drawCard2 = copiedDrawCardPileArray.pop()
                //send new state to server
                socket.emit('updateGameState', {
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    player1Deck: [...player1Deck.slice(0, player1Deck.length), drawCard1, drawCard2, ...player1Deck.slice(player1Deck.length)],
                    currentColor: colorOfDrawnCard,
                    currentNumber: 252,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            else if(drawCard === 'W') {
                alert(`You drew ${drawCard}. It was played for you.`)
                //ask for new color
                const newColor = prompt('Enter first letter of new color in uppercase (R/G/B/Y)')
                //send new state to server
                socket.emit('updateGameState', {
                    turn: 'Player 1',
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    currentColor: newColor,
                    currentNumber: 300,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            else if(drawCard === 'D4W') {
                alert(`You drew ${drawCard}. It was played for you.`)
                //ask for new color
                const newColor = prompt('Enter first letter of new color in uppercase (R/G/B/Y)')
                //remove 2 new cards from drawCardPile and add them to player1's deck (immutably)
                //make a copy of drawCardPile array
                const copiedDrawCardPileArray = [...drawCardPile]
                //pull out last four elements from it
                const drawCard1 = copiedDrawCardPileArray.pop()
                const drawCard2 = copiedDrawCardPileArray.pop()
                const drawCard3 = copiedDrawCardPileArray.pop()
                const drawCard4 = copiedDrawCardPileArray.pop()
                //send new state to server
                socket.emit('updateGameState', {
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    player1Deck: [...player1Deck.slice(0, player1Deck.length), drawCard1, drawCard2, drawCard3, drawCard4, ...player1Deck.slice(player1Deck.length)],
                    currentColor: newColor,
                    currentNumber: 600,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            //if not action card - check if drawn card is playable
            else if(numberOfDrawnCard === currentNumber || colorOfDrawnCard === currentColor) {
                alert(`You drew ${drawCard}. It was played for you.`)
                //send new state to server
                socket.emit('updateGameState', {
                    turn: 'Player 1',
                    playedCardsPile: [...playedCardsPile.slice(0, playedCardsPile.length), drawCard, ...playedCardsPile.slice(playedCardsPile.length)],
                    currentColor: colorOfDrawnCard,
                    currentNumber: numberOfDrawnCard,
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
            //else add the drawn card to player2's deck
            else {
                alert(`You drew ${drawCard}.`)
                //send new state to server
                socket.emit('updateGameState', {
                    turn: 'Player 1',
                    player2Deck: [...player2Deck.slice(0, player2Deck.length), drawCard, ...player2Deck.slice(player2Deck.length)],
                    drawCardPile: [...copiedDrawCardPileArray]
                })
            }
        }
    }
    
    return (
        <div className='Game backgroundColor0'>
            {(!roomFull) ? <>

                <div className='topInfo'>
                    <h1>Logo here</h1>
                    <h1>Game Code: {room}</h1>
                    <div><div onClick={() => changeBackgroundColor(0)} className='square color0' /><div onClick={() => changeBackgroundColor(1)} className='square color1' /><div onClick={() => changeBackgroundColor(2)} className='square color2' /><div onClick={() => changeBackgroundColor(3)} className='square color3' /><div onClick={() => changeBackgroundColor(4)} className='square color4' /></div>
                </div>

                {users.length===1 && currentUser === 'Player 2' && <h1 className='topInfoText'>Player 1 has left the game.</h1> }

                {users.length===1 && currentUser === 'Player 1' && <h1 className='topInfoText'>Waiting for Player 2 to join the game.</h1> }

                {users.length===2 && <>

                    {gameOver ? <div>{winner !== '' && <><h1>GAME OVER</h1><h2>{winner} wins!</h2></>}</div> :
                    <div>
                        {currentUser === 'Player 1' && <>
                        <div className='waitingForPlayer'>
                            {turn==='Player 2' && <h1 className='topInfoText'>Waiting for Player 2 to play!</h1>}
                        </div>
                        <div className='player1Deck' style={turn === 'Player 1' ? null : {pointerEvents: 'none'}}>
                            {player1Deck.map((item, i) => (
                                <img
                                    key={i}
                                    className='Card'
                                    onClick={() => onCardPlayedHandler(item)}
                                    src={require(`../assets/cards-front/${item}.png`).default}
                                    />
                            ))}
                        </div>
                        <br />
                        <div>
                            {playedCardsPile && playedCardsPile.length>0 &&
                            <img
                                className='Card'
                                src={require(`../assets/cards-front/${playedCardsPile[playedCardsPile.length-1]}.png`).default}
                                /> }
                            <button disabled={turn !== 'Player 1'} onClick={onCardDrawnHandler}>DRAW CARD</button>
                        </div>
                        <br />
                        <div className='player2Deck' style={{pointerEvents: 'none'}}>
                            {player2Deck.map((item, i) => (
                                <img
                                    key={i}
                                    className='Card'
                                    onClick={() => onCardPlayedHandler(item)}
                                    src={require(`../assets/card-back.png`).default}
                                    />
                            ))}
                        </div> </> }

                        {currentUser === 'Player 2' && <>
                        {turn==='Player 1' && <h1>Waiting for Player 1 to play!</h1>}
                        <div className='player1Deck' style={{pointerEvents: 'none'}}>
                            {player1Deck.map((item, i) => (
                                <img
                                    key={i}
                                    className='Card'
                                    onClick={() => onCardPlayedHandler(item)}
                                    src={require(`../assets/card-back.png`).default}
                                    />
                            ))}
                        </div>
                        <br />
                        <div>
                            {playedCardsPile && playedCardsPile.length>0 &&
                            <img
                                className='Card'
                                src={require(`../assets/cards-front/${playedCardsPile[playedCardsPile.length-1]}.png`).default}
                                /> }
                            <button disabled={turn !== 'Player 2'} onClick={onCardDrawnHandler}>DRAW CARD</button>
                        </div>
                        <br />
                        <div className='player2Deck' style={turn === 'Player 1' ? {pointerEvents: 'none'} : null}>
                            {player2Deck.map((item, i) => (
                                <img
                                    key={i}
                                    className='Card'
                                    onClick={() => onCardPlayedHandler(item)}
                                    src={require(`../assets/cards-front/${item}.png`).default}
                                    />
                            ))}                            
                        </div> </> }
                    </div> }

                </> }

            </> : <h1 style={{margin: '0'}}>Room full</h1> }

            <br />
            <a href='/'>Forfeit Game</a>
        </div>
    )
}

export default Game