"use strict";

const express = require("express"),
  crypto = require("crypto"),
  { readFile, writeFile } = require("fs").promises,
  fs = require("fs"),
  accessSync = fs.accessSync,
  randomWords = require("random-words");

let gameDB;

require("../db/games").then(function(db) {
  gameDB = db;
});

const router = express.Router();

function shuffle(array) {
  var currentIndex = array.length, temporaryValue, randomIndex;

  // While there remain elements to shuffle...
  while (0 !== currentIndex) {

    // Pick a remaining element...
    randomIndex = Math.floor(Math.random() * currentIndex);
    currentIndex -= 1;

    // And swap it with the current element.
    temporaryValue = array[currentIndex];
    array[currentIndex] = array[randomIndex];
    array[randomIndex] = temporaryValue;
  }

  return array;
}

const assetData = {
  tiles: [
    { type: "robber", card: 0 },
    { type: "wood", card: 0 },
    { type: "wood", card: 1 },
    { type: "wood", card: 2 },
    { type: "wood", card: 3 },
    { type: "wheat", card: 0 },
    { type: "wheat", card: 1 },
    { type: "wheat", card: 2 },
    { type: "wheat", card: 3 },
    { type: "stone", card: 0 },
    { type: "stone", card: 1 },
    { type: "stone", card: 2 },
    { type: "sheep", card: 0 },
    { type: "sheep", card: 1 },
    { type: "sheep", card: 2 },
    { type: "sheep", card: 3 },
    { type: "brick", card: 0 },
    { type: "brick", card: 1 },
    { type: "brick", card: 2 }
  ],
  pips: [
    { roll:  7, pips: 0 },
    { roll:  5, pips: 4 },
    { roll:  2, pips: 1 },
    { roll:  6, pips: 5 },
    { roll:  3, pips: 2 },
    { roll:  8, pips: 5 },
    { roll: 10, pips: 3 },
    { roll:  9, pips: 4 },
    { roll: 12, pips: 1 },
    { roll: 11, pips: 2 },
    { roll:  4, pips: 3 },
    { roll:  8, pips: 5 },
    { roll: 10, pips: 3 },
    { roll:  9, pips: 4 },
    { roll:  4, pips: 3 },
    { roll:  5, pips: 4 },
    { roll:  6, pips: 6 },
    { roll:  3, pips: 2 },
    { roll: 11, pips: 2 }
  ],
  borders: [
    { left: "sheep", right: "bank" },
    { center: "sheep" },
    { left: "wheat", right: "bank" },
    { center: "wood" },
    { left: "sheep", right: "bank" },
    { center: "bank" }
  ],
  developmentCards: []
};
for (let i = 0; i < 14; i++) {
  assetData.developmentCards.push("knight");
}
for (let i = 0; i < 6; i++) {
  assetData.developmentCards.push("progress");
}
for (let i = 0; i < 5; i++) {
  assetData.developmentCards.push("victoryPoint");
}

const games = {};

const processTies = (players) => {
  players.sort((A, B) => {
    if (A.order === B.order) {
      return B.orderRoll - A.orderRoll;
    }
    return A.order - B.order;
  });

  /* Sort the players into buckets based on their 
   * order, and their current roll. If a resulting
   * roll array has more than one element, then there
   * is a tie that must be resolved */

  let slots = [];
  players.forEach(player => {
    if (!slots[player.order]) {
      slots[player.order] = [];
    }
    if (!(player.orderRoll in slots[player.order])) {
      slots[player.order][player.orderRoll] = [];
    }
    slots[player.order][player.orderRoll].push(player);
  });

  let ties = false, order = 0;
  slots.forEach((slot) => {
    slot.forEach(pips => {
      if (pips.length !== 1) {
        ties = true;
        pips.forEach(player => {
          player.orderRoll = 0;
          player.order = order;
          player.orderStatus = `Tied for ${order+1}.`;
        });
      } else {
        pips[0].order = order;
        pips[0].orderStatus = `Placed in ${order+1}.`;
      }
      order += pips.length
    })
  });

  return !ties;
}


const getPlayerName = (game, player) => {
  for (let id in game.sessions) {
    if (game.sessions[id].player === player) {
      return game.sessions[id].name;
    }
  }
  return '';
};

const processGameOrder = (game, player, dice) => {
  let message;

  player.orderRoll = dice;

  let players = [];

  let doneRolling = true;

  for (let key in game.players) {
    const tmp = game.players[key];
    if (tmp.status === 'Not active') {
      continue;
    }
    if (!tmp.orderRoll) {
      doneRolling = false;
    }
    
    players.push(tmp);
  }

  /* If 'doneRolling' is TRUE then everyone has rolled */
  if (doneRolling) {
    if (processTies(players)) {
      message = `Player order set to ${players.map((player, index) => {
        return `${index+1}. ${getPlayerName(game, player)}`;
      }).join(', ')}.`;
      game.chat.push({ date: Date.now(), message: message });
      game.state = 'active'
      message = `Game has started!`;
    } else {
      message = `There are still ties for player order!`;
    }
  }

  if (message) {
    game.chat.push({ date: Date.now(), message: message });
  }
}

const roll = (game, session) => {
  let message, error;

  const player = session.player,
    name = session.name ? session.name : "Unnamed";

  switch (game.state) {
  case "lobby":
    error = `Rolling dice in the lobby is not allowed!`;

  case "game-order":
    if (!player) {
      error = `This player is not active!`;
      break;
    }
    
    if (player.order || player.orderRoll) {
      error = `Player ${name} has already rolled for player order.`;
      break;
    }

    game.dice = [ Math.ceil(Math.random() * 6) ];
    processGameOrder(game, player, game.dice[0]);
    break;

  case "active":
    game.dice = [ Math.ceil(Math.random() * 6), Math.ceil(Math.random() * 6) ];
    message = `${name} rolled ${game.dice[0] + game.dice[1]}.`;
    break;

  default:
    error = `Invalid game state (${game.state}) in roll.`;
    break;
  }

  if (!error && message) {
    game.chat.push({ from: session.color, date: Date.now(),  message: message });
  }
  return error;
};

const getPlayer = (game, color) => {
  if (!game) {
    return {
      roads: 15, 
      cities: 4, 
      settlements: 5, 
      points: 0, 
      status: "Not active", 
      lastActive: 0,
      order: 0
    };
  }

  return game.players[color];
};

const getSession = (game, session) => {
  if (!game.sessions) {
    game.sessions = {};
  }

  if (!session.player_id) {
    session.player_id = crypto.randomBytes(32).toString('hex');
  }

  const id = session.player_id;

  /* If this session is not yet in the game,
   * add it and set the player's name */
  if (!(id in game.sessions)) {
    game.sessions[id] = {
      name: undefined,
      color: undefined,
      player: undefined
    };
  }

  return game.sessions[id];
};

const loadGame = async (id) => {
  if (/^\.|\//.exec(id)) {
    return undefined;
  }

  if (id in games) {
    return games[id];
  }

  let game = await readFile(`games/${id}`)
  .catch(() => {
    return;
  });

  if (!game) {
    game = createGame(id);
  } else {
    try {
      game = JSON.parse(game);
    } catch (error) {
      console.error(error, game);
      return null;
    }
  }

  if (!game.pipOrder || !game.borderOrder || !game.tileOrder) {
    console.log("Shuffling old save file");
    shuffleBoard(game);
  }

  if (!game.pips || !game.borders || !game.tiles) {
    [ "pips", "borders", "tiles" ].forEach((field) => {
      game[field] = assetData[field]
    });
  }

  /* Reconnect session player colors to the player objects */
  for (let id in game.sessions) {
    const session = game.sessions[id];
    if (session.color && session.color in game.players) {
      session.player = game.players[session.color];
    } else {
      session.color = undefined;
      session.player = undefined;
    }
  }

  games[id] = game;
  return game;
};

const clearPlayer = (player) => {
  player.status = 'Not active';
  player.lastActive = 0;
  player.order = 0;
  delete player.orderRoll;
  delete player.orderStatus;
}

const adminActions = (game, action, value) => {
  let color, player;

  switch (action) {
  case "state":
    switch (value) {
    case 'game-order':
      for (let key in game.players) {
        game.players[key].order = 0;
        delete game.players[key].orderRoll;
        delete game.players[key].orderStatus;
      }
      game.state = 'game-order';
      break;
    }
    break;

  case "roll":
    let dice = value.replace(/.*-/, '');
    switch (value.replace(/-.*/, '')) {
    case 'orange': color = 'O'; break;
    case 'red': color = 'R'; break;
    case 'blue': color = 'B'; break;
    case 'white': color = 'W'; break;
    }
    if (!color) {
      return `Unable to find player ${value.replace(/-.*/, '')}`
    }
    
    player = game.players[color];
    processGameOrder(game, player, dice);
    
    break;

  case "kick":
    switch (value) {
    case 'orange': color = 'O'; break;
    case 'red': color = 'R'; break;
    case 'blue': color = 'B'; break;
    case 'white': color = 'W'; break;
    }
    if (!color) {
      return `Unable to find player ${value}`
    }
  
    player = game.players[color];
    for (let id in game.sessions) {
      const session = game.sessions[id];
      if (session.player !== player) {
        continue;
      }
      console.log(`Kicking ${value} from ${game.id}.`);
      const preamble = session.name ? `${session.name}, playing as ${color},` : color;
      game.chat.push({
        date: Date.now(),
        message: `${preamble} was kicked from game by the Admin.`
      });
      if (player) {
        session.player = undefined;
        clearPlayer(player);
      }
      session.color = undefined;
      return;
    }
    return `Unable to find active session for ${color} (${value})`;

  default:
    return `Invalid admin action ${action}.`;
  }
};

const setPlayerName = (game, session, name) => {
  if (session.color) {
    return `You cannot change your name while you are in game.`;
  }
  
  /* Check to ensure name is not already in use */
  if (game && name) for (let key in game.sessions) {
    const tmp = game.sessions[key];
    if (tmp.name && tmp.name.toLowerCase() === name.toLowerCase()) {
      return `${name} is already taken.`;
    }
  }
  
  const old = session.name;
  let message;

  session.name = name;
  
  if (name) {
    if (!old) {
      message = `A new player has entered the lobby as ${name}.`;
    } else {
      message = `${old} has changed their name to ${name}.`;
    }
  } else {
    return `You can not set your name to nothing!`;
  }
  
  game.chat.push({
    date: Date.now(),
    message: message
  });
}

const setPlayerColor = (game, session, color) => {
  if (!game) {
    return `No game found`;
  }
  
  const name = session.name, player = session.player;

  /* Selecting the same color is a NO-OP */
  if (session.color === color) {
    return;
  }

  const priorActive = getActiveCount(game);

  if (player) {
    /* Deselect currently active player for this session */
    clearPlayer(player);
    let message;
    if (game.state !== 'lobby') {
      message = `${name} has exited to the lobby and is no longer playing as ${session.color}.`
    } else {
      message = `${name} is no longer ${session.color}.`;
    }
    game.chat.push({
      date: Date.now(),
      message: message
    });
    session.player = undefined;
    session.color = undefined;
  }

  /* Verify the player has a name set */
  if (!name) {
    return `You may only select a player when you have set your name.`;
  }

  /* If the player is not selecting a color, then return */
  if (!color) {
    return;
  }

  /* Verify selection is valid */
  if (!(color in game.players)) {
    return `An invalid player selection was attempted.`;
  }

  /* Verify selection is not already taken */
  for (let key in game.sessions) {
    const tmp = game.sessions[key].player;
    if (tmp && tmp.color === color) {
      return `${game.sessions[key].name} already has ${color}`;
    }
  }

  /* All good -- set this player to requested selection */
  session.player = getPlayer(game, color);

  session.player.status = `Active`;
  session.player.lastActive = Date.now();
  session.color = color;
  game.chat.push({
    from: color,
    date: Date.now(),
    message: `${session.name} has chosen to play as ${color}.`
  });

  const afterActive = getActiveCount(game);
  if (afterActive !== priorActive) {
    if (priorActive < 2 && afterActive >= 2) {
      game.chat.push({
        date: Date.now(),
        message: `There are now enough players to start the game when you are ready.`
      });
    }
  }
};

router.put("/:id/:action/:value?", async (req, res) => {
  const { action, id } = req.params,
    value = req.params.value ? req.params.value : "";
  console.log(`PUT games/${id}/${action}/${value}`);

  const game = await loadGame(id);
  if (!game) {
    const error = `Game not found and cannot be created: ${id}`;
    return res.status(404).send(error);
  }

  let error;

  if ('private-token' in req.headers) {
    if (req.headers['private-token'] !== req.app.get('admin')) {
      error = `Invalid admin credentials.`;
    } else {
      error = adminActions(game, action, value);
    }
    return sendGame(req, res, game, error);
  }

  const session = getSession(game, req.session);
  
  switch (action) {
  case 'player-name':
    error = setPlayerName(game, session, value);
    return sendGame(req, res, game, error);
  case 'player-selected':
    error = setPlayerColor(game, session, value);
    return sendGame(req, res, game, error);
  }

  if (!session.player) {
    error = `Player must have an active color.`;
    return sendGame(req, res, game, error);
  }

  const name = session.name;
  let message;

  switch (action) {
  case "roll":
    error = roll(game, session);
    break;
  case "shuffle":
    if (game.state !== "lobby") {
      error = `Game no longer in lobby (${game.state}). Can not shuffle board.`;
    }
    if (!error && game.turns > 0) {
      error = `Game already in progress (${game.turns} so far!) and cannot be shuffled.`;
    }
    if (!error) {
      shuffleBoard(game);
      const message = `${name} requested a new board.`;
      game.chat.push({ date: Date.now(),  message: message });
      console.log(message);
    }
    break
  case "state":
    const state = value;
    if (!state) {
      error = `Invalid state.`;
      break;
    }

    if (state === game.state) {
      break;
    }

    switch (state) {
    case "game-order":
      if (game.state !== 'lobby') {
        error = `You cannot start a game from other than the lobby.`;
        break;
      }

      for (let key in game.players) {
        game.players[key].order = 0;
        delete game.players[key].orderRoll;
        delete game.players[key].orderStatus;
      }
    
      message = `${name} requested to start the game.`;
      game.chat.push({ date: Date.now(),  message: message });
      game.state = state;
      break;
    }
    break;
  }

  return sendGame(req, res, game, error);
})

router.get("/:id", async (req, res/*, next*/) => {
  const { id } = req.params;
//  console.log("GET games/" + id);

  let game = await loadGame(id);
  if (game) {
    return sendGame(req, res, game)
  }

  game = createGame(id);

  return sendGame(req, res, game);
});

router.put("/:id", (req, res/*, next*/) => {
  const { id } = req.params;

  console.log("PUT games/" + id);
  if (!(id in games)) {
    const error = `Game not found: ${req.params.id}`;
    return res.status(404).send(error);
  }

  const game = games[id],
    changes = req.body;

  for (let change in changes) {
    switch (change) {
    case "chat":
      console.log("Chat change.");
      game.chat.push({
        from: changes.chat.player,
        date: Date.now(),
        message: changes.chat.message
      });
/*
      if (game.chat.length > 10) {
        game.chat.splice(0, game.chat.length - 10);
      }
*/
      break;
    }
  }
  return sendGame(req, res, game);
});

const getActiveCount = (game) => {
  let active = 0;
  for (let color in game.players) {
    const player = game.players[color];
    active += ((player.status && player.status != 'Not active') ? 1 : 0);
  }
  return active;
}

const sendGame = async (req, res, game, error) => {
  const active = getActiveCount(game);

  /* Enforce game limit of >= 2 players */
  if (active < 2 && game.state != 'lobby' && game.state != 'invalid') {
    let message = "Insufficient players in game. Setting back to lobby."
    console.log(game);
    game.chat.push({ date: Date.now(),  message: message });
    console.log(message);
    game.state = 'lobby';
  }
  game.active = active;
  
  /* Update the session lastActive clock */
  let session;
  if (req.session) {
    session = getSession(game, req.session);
    session.lastActive = Date.now();
    if (session.player) {
      session.player.lastActive = session.lastActive;
    }
  } else {
    session = {
      name: "command line"
    };
  }
  
  /* Ensure chat messages have a unique date: stamp as it is used as the index key */
  let lastTime = 0;
  if (game.chat) game.chat.forEach((message) => {
    if (message.date <= lastTime) {
      message.date = lastTime + 1;
    }
    lastTime = message.date;
  });

  /* Shallow copy game, filling its sessions with a shallow copy of sessions so we can then
   * delete the player field from them */
  const reducedGame = Object.assign({}, game, { sessions: {} }),
    reducedSessions = [];
  
  for (let id in game.sessions) {
    const reduced = Object.assign({}, game.sessions[id]);
    if (reduced.player) {
      delete reduced.player;
    }
    reducedGame.sessions[id] = reduced;

    /* Do not send session-id as those are secrets */
    reducedSessions.push(reduced);
  }

  await writeFile(`games/${game.id}`, JSON.stringify(reducedGame, null, 2))
  .catch((error) => {
    console.error(`Unable to write to games/${game.id}`);
    console.error(error);
  });

  const playerGame = Object.assign({}, reducedGame, {
    timestamp: Date.now(),
    status: error ? error : "success",
    name: session.name,
    color: session.color,
    order: (session.color in game.players) ? game.players[session.color].order : 0,
    sessions: reducedSessions
  });

  return res.status(200).send(playerGame);
}

const createGame = (id) => {
  /* Look for a new game with random words that does not already exist */
  while (!id) {
    id = randomWords(4).join('_');
    console.log(`Looking for ${id}`);
    try {
      /* If file can be read, it already exists so look for a new name */
      accessSync(`games/${id}`, fs.F_OK);
      id = '';
    } catch (error) {
      console.log(error);
      break;
    }
  }

  const game = {
    startTime: Date.now(),
    turns: 0,
    state: "lobby", /* lobby, active, finished */
    tokens: [],
    players: {
      R: getPlayer(),
      O: getPlayer(),
      B: getPlayer(),
      W: getPlayer()
    },
    developmentCards: assetData.developmentCards.slice(),
    dice: [ 0, 0 ],
    sheep: 19,
    ore: 19,
    wool: 19,
    brick: 19,
    wheat: 19,
    longestRoad: null,
    largestArmy: null,
    chat: [ { date: Date.now(), message: `New game started for ${id}` } ],
    id: id
  };

  [ "pips", "borders", "tiles" ].forEach((field) => {
    game[field] = assetData[field]
  });

  games[game.id] = game;
  shuffleBoard(game);
  console.log(`New game created: ${game.id}`);
  return game;
};

router.post("/:id?", (req, res/*, next*/) => {
  console.log("POST games/");
  const { id } = req.params;
  if (id && id in games) {
    const error = `Can not create new game for ${id} -- it already exists.`
    console.error(error);
    return res.status(400).send(error);
  }

  const game = createGame(id);

  return sendGame(req, res, game);
});

const shuffleBoard = (game) => {
  const seq = [];
  for (let i = 0; i < 6; i++) {
    seq.push(i);
  }
  shuffle(seq);
  game.borderOrder = seq.slice();
  for (let i = 6; i < 19; i++) {
    seq.push(i);
  }
  shuffle(seq);
  game.tileOrder = seq.slice();

  /* Pip order is from one of the random corners, then rotate around
   * and skip over the desert (robber) */

  /* Board:
   *       0     1     2
   *    3      4     5     6
   *  7    8    9      10    11
   *    12   13    14     15 
   *       16   17     18    
   */
  const order = [
    [ 0, 1, 2, 6, 11, 15, 18, 17, 16, 12, 7, 3, 4, 5, 10, 14, 13, 8, 9 ],
    [ 2, 6, 11, 15, 18, 17, 16, 12, 7, 3, 0, 1, 5, 10, 14, 13, 8, 4, 9 ],
    [ 11, 15, 18, 17, 16, 12, 7, 3, 0, 1, 2, 6, 10, 14, 13, 8, 4, 5, 9 ],
    [ 18, 17, 16, 12, 7, 3, 0, 1, 2, 6, 11, 15, 14, 13, 8, 4, 5, 10, 9 ],
    [ 16, 12, 7, 3, 0, 1, 2, 6, 11, 15, 18, 17, 13, 8, 4, 5, 10, 14, 9 ],
    [ 7, 3, 0, 1, 2, 6, 11, 15, 18, 17, 16, 12, 8, 4, 5, 10, 14, 13, 9 ]
  ]
  const sequence = order[Math.floor(Math.random() * order.length)];
  game.pipOrder = [];
  for (let i = 0, p = 0; i < sequence.length; i++) {
    const target = sequence[i];
    /* If the target tile is the desert (18), then set the
     * pip value to the robber (18) otherwise set
     * the target pip value to the currently incremeneting
     * pip value. */ 
    if (game.tiles[game.tileOrder[target]].type === 'desert') {
      game.pipOrder[target] = 18;
    } else {
      game.pipOrder[target] = p++;
    }
  }

   shuffle(game.developmentCards)
}

/*
  return gameDB.sequelize.query("SELECT " +
    "photos.*,albums.path AS path,photohashes.hash,modified,(albums.path || photos.filename) AS filepath FROM photos " +
    "LEFT JOIN albums ON albums.id=photos.albumId " +
    "LEFT JOIN photohashes ON photohashes.photoId=photos.id " +
    "WHERE photos.id=:id", {
    replacements: {
      id: id
    }, type: gameDB.Sequelize.QueryTypes.SELECT,
    raw: true
  }).then(function(photos) {
    if (photos.length == 0) {
      return null;
    }
    */
if (0) {
router.get("/*", (req, res/*, next*/) => {
  return gameDB.sequelize.query(query, {
    replacements: replacements, type: gameDB.Sequelize.QueryTypes.SELECT
  }).then((photos) => {
  });
});
}

module.exports = router;