//////////////////////////////////// Game Class ////////////////////////////////

function Game() {
    this.receive_poll_interval = 1000; // ms
    this.opponent_poll_interval = 1000; // ms
}

Game.prototype.wait_for_opponent = function() {
    var opponent_waiting = retrieve('opponent_waiting','script');
    if (!opponent_waiting) {
        this.first = 1; // I was here first
        store_now(true,'opponent_waiting','script');
        this.game_id = 1*(new Date()); // 1* converts to number
        store_now(this.game_id,'game_id','script'); 
        while (true) {
            if(!retrieve('opponent_waiting','script')) {
                this.game_id = retrieve('game_id','script');
                break;
            } else {
                await(this.opponent_poll_interval);
            }
        }
    } else {
        this.game_id = retrieve('game_id','script');
        store_now(false,'opponent_waiting','script'); // Affirm by clearing
        this.first = false; // I was second; someone was already waiting
    }
}

// Sends content over (optional) named channel and waits until it has been received 
Game.prototype.send = function(content,channel) {
    content = {
        data: content
    }
    content = JSON.stringify(content); // Ensure correct JSON-ification on server
    channel = channel || "channel";
    var id = channel + '_' + this.game_id,
        signal;
    store_now(content,id,'script');
    while (true) {
        signal = retrieve(id,'script');
        if(signal) { // Wait until the signal has cleared, i.e., has been received
            await(this.receive_poll_interval);
        } else {
            break;
        }
    }
}

// Receive content over (optionally) named channel. Waits until reception.
Game.prototype.receive = function(channel) {
    channel = channel || "channel";
    var id = channel + '_' + this.game_id,
        signal;
    while (true) {
        signal = retrieve(id,'script');
        if(signal) {
            store_now(false,id,'script'); // clear channel; signals reception
            return signal.data;
        } else {
            await(this.receive_poll_interval); // wait and try again
        }
    }
}

////////////////////////////////// End Game Class ///////////////////////////////


text("Waiting for opponent");
var game = new Game();
game.wait_for_opponent();
clear();

/*
var first_turn = true;
while (true) { // Simple turn-taking chat
    if (game.first && first_turn) { // first_turn helps determine who sends first
        first_turn = false;
        input("Send message","message");
        game.send(response.message);
        text("Message received");
    } else {
        text("Waiting for message")
        var msg = game.receive();
        text(msg);
        await(5000);
        input("Send message","message");
        game.send(response.message);
        text("Message received");
    }
}
*/

var r, c, blocks = [], b, selected_block,
    header = addblock(21,1,60,16);

for (r = 0; r < 3; ++r) {
    for (c = 0; c < 3; ++c) {
        b = addblock(21+r*20,21+c*20,18,18,"lightgrey");
        b.on("click",onClick(b));
        b.index = r*3 + c;
        blocks.push(b);
    }
}

function onClick(block) {
    return function() {
        if (block.used || !your_turn) { // Cannot change X or O, if already one present
            return; // Also, you can only make a move if it is your turn
        }
        your_turn = false;
        var b = block, // This ties the block to this function
            event;
        b.style("background-color","yellow"); // Show as selected
        event = awaitkey("o,x"); // Wait for either the O or X key to be pressed
        b.text(event.key,200);   // Show the key's letter at size 200%
        b.style("background-color","lightgrey"); // Show as not selected
        b.used = true;  // This block (position) has been taken
        b.letter = event.key;
        game.send({index:b.index,letter:b.letter});
        header.text("Waiting for response");
        if (checkWinner()) {
            header.text("You won!");
        }
        // After having sent a letter, wait for the response
        var r = game.receive(); // Here comes the letter
        blocks[r.index].letter = r.letter;
        blocks[r.index].text(r.letter,200);
        if (checkWinner()) { // Did my opponent win?
            header.text("You lost!");
        } else {
            header.text("Your turn"); // If not, I can try and click again
            your_turn = true;
        }
    }
}

function checkWinner() {
    var b = blocks;
    
    function check(x,y,z) { 
        if ((b[x].letter === b[y].letter && b[y].letter === b[z].letter) 
                && b[x].letter) {  // Include last to check for empty string
            return [x,y,z];                
        }
    }
    
    var winner = check(0,1,2) || check(3,4,5) || check (6,7,8)
            || check(0,3,6) || check(1,4,7) || check(2,5,8)
            || check(0,4,8) || check(2,4,6);
    if (winner) {
        await(500);
        blocks[winner[0]].style("background-color","orange");
        blocks[winner[1]].style("background-color","orange");
        blocks[winner[2]].style("background-color","orange");
        return winner;
    }
}

var first_turn = true, 
    your_turn = false;
    
if (game.first && first_turn) { // first_turn helps determine who sends first
    first_turn = false;
    header.text("Your can start");
    your_turn = true;
} else {
    var r = game.receive(); // Here comes the letter
    blocks[r.index].letter = r.letter;
    blocks[r.index].text(r.letter,200);
    header.text("Your turn"); 
    your_turn = true;
}

awaitkey("ESCAPE"); // At any point, you can press Escape and quit
// Normally we would send a message to the opponent