Screen.Game = function(modules) {
  var deck = document.getElementById("deck");
  var rest = document.getElementById("rest");
  var status = {
    dom: document.getElementById("status"),
    game: null,
    playing: false,
    step: null,
    month: null
  };
  var sets = buildSets();
  var selected = null;
  var turnedCard = null;
	var queue = [];

  function buildSets() {
    var sets = {};
    ['river', 'you', 'them'].forEach(function(id) {
      var dom = document.getElementById(id);
      if(dom.tagName.toLowerCase() == 'ul') {
        sets[id] = {card: null, dom: dom};
      } else {
        sets[id] = {};
        for(var i = 0; i < dom.children.length; i++) {
          if(dom.children[i].tagName.toLowerCase() == 'ul') {
            sets[id][dom.children[i].className] = {card: {}, dom: dom.children[i]};
          }
        }
      }
    });
    return sets;
  }

	window.addEventListener('focus', runQueue);
  modules.messaging.addEventListener(["Game"], function(o) {
		queue.push(handleGameMessage(o));
		if(document.hasFocus() && queue.length == 1) {
			runQueue();
		} else {
			modules.statusHandler.set("♪");
		}
	});

	function runQueue() {
		if(queue.length > 0) {
			var length = queue.length;
			modules.async.run.apply(null, queue.concat(
				modules.async.apply(function() {
					queue = queue.slice(length);
					runQueue();
				})
			));
		}
	}

	function handleGameMessage(o) {
		if(o.state.public.turns == 0) {
			if(o.logs.length > 0) { // but still some logs, from the previous round
				return modules.async.sequence(applyDiff(o), setGame(o)); // so play the diff, then set the new round
			} else {
				return setGame(o); // directly set a whole new game
			}
		} else {
			return applyDiff(o);
		}
	}

	function setGame(o) {
		return function(f) {
			setStatus(o.state);
			setCaptures(o.state);
			[
				[sets.river, o.state.public.river, RiverCard],
				[sets.you.hand, o.state.playerHand, HandCard]
			].forEach(function(args) {setCardSet.apply(null, args)});
			setTheirCards(o.state);
			handleStep(o)(f);
		};
	}

	function handleStep(o) {
		return function(f) {
			handleTurnedCard(o, f);
			if(status.step == "Scored") {
				if(status.playing) {
					askKoikoi(o, f);
				} else {
					theyScored(o, f);
				}
			} else if (status.step == "Over") {
				gameEnd(o, f);
			} else {
				f();
			}
		};
	}

	function handleTurnedCard(o, f) {
		if(status.step == "Turned") {
			setTurned(o.state.public.step.contents);
		} else {
			if(status.step == "ToPlay" && o.state.public.playing == o.state.public.oyake) {
				rest.className = ["card", "turn" + o.state.public.turns].join(' ');
			}
			if(deck.lastChild.id != "rest") {
				deck.removeChild(deck.lastChild);
			}
		}
	}

	function askKoikoi(o, f) {
		modules.screen.dialog({
			text: modules.i18n.get('youScored'),
			answers: [
				{label: 'endRound', action: function() {play({koiKoi: false}); f();}},
				{label: 'koikoi', action: function() {play({koiKoi: true}); f();}}
			]
		});

	}

	function theyScored(o, f) {
		modules.screen.dialog({
			text: modules.i18n.get('theyScored')(modules.room.name(o.state.public.playing)),
			answers: [
				{label: 'ok', action: f}
			]
		});
	}

	function gameEnd(o, f) {
		var winner, maxScore;
		for(var key in o.state.public.scores) {
			if(maxScore == undefined || o.state.public.scores[key] > maxScore) {
				winner = key;
				maxScore = o.state.public.scores[key];
			}
		}
		modules.screen.dialog({
			text: modules.i18n.get(modules.session.is(winner) ? 'won' : 'lost'),
			answers: [{
				label: 'endGame',
				action: function() {
					modules.messaging.send({tag: "Quit"});
					modules.screen.select('reception');
					f();
				}
			}]
		});
	}

	function applyDiff(o) {
		return modules.async.sequence.apply(null,
			o.logs.map(animate).concat(
				modules.async.apply(setStatus, o.state),
				handleStep(o)
			)
		);
	}

  function animate(movement) {
		return modules.async.bind(
			modules.async.apply(function() {
				var card;
    		var movingCards = [];
    		var side = (status.playing) ? 'you' : 'them';
    		var dest = sets.river;
				if(movement.captures != undefined) {
					card = new Card(movement.played);
    		  dest = sets[side];
					movingCards.push([sets.river, dest, new Card(movement.captures)]);
				} else {
					card = new RiverCard(movement.played);
				}
				if(movement.source == 'Hand') {
					movingCards.push([sets[side].hand, dest, card]);
				} else {
					var cardSet = {};
					cardSet[card.name] = turnedCard || new TurnedCard(card.name);
					turnedCard = null;
					movingCards.push([{card: cardSet, dom: deck}, dest, card]);
				}
				return movingCards;
			}),
			function(movingCards) {
				return modules.async.parallel.apply(null,
					movingCards.map(function(args) { return moveCard.apply(null, args); })
				);
			}
		);
  }

  function moveCard(fromSet, toSet, card) {
    var from, originalCard;
    var slot = modules.dom.make('li', {class: ['card', 'slot']});
    if (fromSet.card[card.name] != undefined) {
			originalCard = fromSet.card[card.name].dom;
			delete fromSet.card[card.name];
		} else {
      var originalCard = fromSet.dom.children[fromSet.dom.children.length - 1];
    }
		from = originalCard.getBoundingClientRect();
		fromSet.dom.replaceChild(slot, originalCard);
    card.dom.style.visibility = 'hidden';
    insertCard(toSet, card);
    var to = card.dom.getBoundingClientRect();
    card.dom.style.left = (from.left - to.left) + 'px';
    card.dom.style.top = (from.top - to.top) + 'px';
    card.dom.classList.add('moving');
    card.dom.style.visibility = null;
		return modules.async.sequence(
			modules.async.wait(10),
			modules.async.apply(function() {
				card.dom.style.left = 0;
				card.dom.style.top = 0;
			}),
			modules.async.wait(1000),
			modules.async.apply(function() {
				fromSet.dom.removeChild(slot);
				card.dom.classList.remove('moving');
			})
		);
  }

  function insertCard(toSet, card) {
    if(toSet.dom != undefined) {
      toSet.card[card.name] = card;
      toSet.dom.appendChild(card.dom);
    } else {
      insertCard(toSet[card.value.family.class], card);
    }
  }

  function play(move) {
    modules.messaging.send({
      tag: "Play",
      move: move,
      onGame: status.game
    });
  }

  function matchingInRiver(card) {
    return modules.fun.mapFilter(
      modules.fun.of(sets.river.card),
      modules.fun.defined
    )(modules.hanafuda.sameMonth(card).map(modules.fun.proj('name')));
  }

  function setStatus(game) {
    modules.dom.clear(status.dom);
    status.game = game;
    status.step = game.public.step.tag;
    if(game.public.month != status.month) {
      status.month = game.public.month;
    }
    status.dom.appendChild(
      modules.dom.make('li', {textContent: modules.i18n.get('monthFlower')(modules.i18n.get(status.month))})
    );
    var turn = null;
    status.playing = modules.session.is(game.public.playing);
    if(status.playing) {
      sets.you.hand.dom.classList.toggle("yourTurn", status.step == "ToPlay");
      turn = modules.i18n.get("yourTurn");
    } else {
      sets.you.hand.dom.classList.remove("yourTurn");
      turn = modules.i18n.get('playing')(modules.room.name(game.public.playing));
    }
    status.dom.appendChild(modules.dom.make('li', {textContent: turn}));
  }

  function setCaptures(game) {
    for(var key in game.public.players) {
      var elem = document.getElementById(modules.session.is(key) ? "you" : "them");
      elem.getElementsByClassName('score')[0].textContent = game.public.scores[key] + " pts";
      var byClass = {}
      Object.values(modules.hanafuda.Family).forEach(function(family) {
        byClass[family.class] = elem.getElementsByClassName(family.class)[0];
        modules.dom.clear(byClass[family.class]);
      });
      game.public.players[key].meld.forEach(function(cardName) {
        var card = new Card(cardName);
        byClass[card.value.family.class].appendChild(card.dom);
      });
    }
  }

  function setCardSet(set, cardNames, constructor) {
    constructor = constructor || Card;
    set.card = {};
    modules.dom.clear(set.dom);
    cardNames.forEach(function(cardName) {
      var card = new constructor(cardName);
      set.card[cardName] = card;
      set.dom.appendChild(card.dom);
    });
  }

  function setTheirCards(game) {
    var turnsTheyPlayed = Math.floor(
      (game.public.turns + (modules.session.is(game.public.oyake) ? 0 : 1)) / 2
    );
    modules.dom.clear(sets.them.hand.dom);
    for(var i = 0; i < 8 - turnsTheyPlayed; i++) {
      sets.them.hand.dom.appendChild(modules.dom.make('li', {class: "card"}));
    }
  }

  function setTurned(cardName) {
		turnedCard = new TurnedCard(cardName);
    if(status.playing) {
      selected = turnedCard;
      showCandidates(modules.hanafuda.Card[cardName], true);
    }
  }

  function showCandidates(card, yes) {
    matchingInRiver(card).forEach(function(riverCard) {riverCard.setCandidate(yes);});
  }

  function setSelected(yes) {
    selected = yes ? this : null;
    this.dom.classList.toggle('selected', yes);
    showCandidates(this.value, yes);
  }

  function Card(name) {
    this.value = modules.hanafuda.Card[name];
    this.name = name;
    this.dom = modules.dom.make('li', {
      class: [
        "card",
        "value" + modules.hanafuda.getValue(this.value),
        "month" + this.value.flower
      ],
      onClick: this.onClick()
    });
  }

  Card.prototype.onClick = function() {return function() {};};

  function RiverCard() {
    Card.apply(this, arguments);
    this.candidate = false;
  }

  RiverCard.prototype.onClick = function() {
    var card = this;
    return function() {
      if(card.candidate) {
        var withCard = selected.name;
        selected.setSelected(false);
        play(
          status.step == 'ToPlay' ? {capture: [withCard, card.name]} : {choose: card.name}
        );
      }
    };
  };

  RiverCard.prototype.setCandidate = function(yes) {
    this.candidate = yes;
    this.dom.classList.toggle("candidate", yes);
  }

  function TurnedCard() {
    Card.apply(this, arguments);
    this.dom.id = "turned";
    deck.appendChild(this.dom);
  }

  TurnedCard.prototype.onClick = Card.prototype.onClick;
  TurnedCard.prototype.setSelected = setSelected;

  function HandCard() {
    Card.apply(this, arguments);
  }

  HandCard.prototype.onClick = function() {
    var card = this;
    return function() {
      if(status.playing && status.step == "ToPlay") {
        if(selected != undefined) {
          selected.setSelected(false);
        } else {
          card.play();
        }
      }
    };
  };

  HandCard.prototype.setSelected = setSelected;

  HandCard.prototype.play = function() {
    var matching = matchingInRiver(this.value);
    if(matching.length > 1) {
      this.setSelected(true);
    } else {
      play({play: this.name});
    }
  }
}