battle-text.js

var pokeapi = require('./poke-api.js'),
    stateMachine = require('./state-machine.js'),
    moves = require('./move-types.js'),
    Q = require('q');

//+ Jonas Raoni Soares Silva
//@ http://jsfromhell.com/array/shuffle [v1.0]
function shuffle(o){ //v1.0
    for(var j, x, i = o.length; i; j = Math.floor(Math.random() * i), x = o[--i], o[i] = o[j], o[j] = x);
    return o;
};

module.exports = {}

/*
* Return a text string when the command doesn't match defined commands.
*/
module.exports.unrecognizedCommand = function(commandsArray) {
  var textString = "I don't recognize the command _{cmd}_ .";
  //get rid of the 'pkmn'
  commandsArray.shift();
  textString = textString.replace("{cmd}", commandsArray.join(" "));
  return Q.fcall(function(){ return textString; });
}

/*
* Return a text string when the user chooses a Pokemon.
* Fetch the pokemon from the API, choose 4 random moves, write them to REDIS,
* and then return a message stating the pokemon, its HP, and its moves.
*/
module.exports.userChoosePokemon = function(commandsArray) {
  var commandString = commandsArray.join(" "),
      pokemonName = commandsArray[3],
      textString = "You chose {pkmnn}. It has {hp} HP, and knows ",
      moves = [],
      movePromises = [];
  //validate that the command was "pkmn i choose {pokemon}"
  if(!commandString.match(/i choose/i)) {
    return module.exports.unrecognizedCommand(commandsArray);
  }
  return pokeapi.getPokemon(pokemonName).then(function(pkmndata){
    moves = shuffle(pkmndata.moves);
    for(var i = 0; i < 4; i++) {
      movePromises.push(
        pokeapi.getMove("http://pokeapi.co"+moves[i].resource_uri)
        .then(stateMachine.addMove)
      )
      //format: "vine whip, leer, solar beam, and tackle."
      if(i < 3) {
        textString += moves[i].name;
        textString += ", ";
      } else {
        textString += "and ";
        textString += moves[i].name;
        textString += ".";
      }
    }
    return Q.allSettled(movePromises)
    .then(function(){
      return stateMachine.setUserHP(pkmndata.hp);
    })
    .then(function(){
      return stateMachine.setUserPkmnTypes(pkmndata.types.map(function(val){
        return val.name;
      }));
    })
    .then(function(){
      textString = textString.replace("{pkmnn}", pkmndata.name);
      textString = textString.replace("{hp}", pkmndata.hp);
      var stringy = "" + pkmndata.pkdx_id;
        if (stringy.length == 1) {
          stringy = "00" + stringy;
        } else if (stringy.length == 2) {
          stringy = "0" + stringy;
        }
      return {
        text: textString,
        spriteUrl: "http://sprites.pokecheck.org/i/"+stringy+".gif"
      }
    });    
  });

}

/*
* Return a text string when the NPC chooses a Pokemon.
* Fetch the pokemon from the API, choose 4 random moves, write them to REDIS,
* and then return a message stating the pokemon.
*/
module.exports.npcChoosePokemon = function(dex_no) {
  var textString = "I Choose {pkmnn}!",
      moves = [],
      movePromises = [];
  return pokeapi.getPokemon(dex_no).then(function(pkmnData){
    moves = shuffle(pkmnData.moves);
    for(var i = 0; i < 4; i++) {
      movePromises.push(
        pokeapi.getMove("http://pokeapi.co"+moves[i].resource_uri)
        .then(stateMachine.addMoveNPC)
      )
    }
    return Q.allSettled(movePromises)
    .then(function(){
      return stateMachine.setNpcHP(pkmnData.hp);
    })
    .then(function(){
      return stateMachine.setNpcPkmnTypes(pkmnData.types.map(function(val){
        return val.name;
      }));
    })
    .then(function(){
        textString = textString.replace("{pkmnn}", pkmnData.name);
        var stringy = "" + pkmnData.pkdx_id;
        if (stringy.length == 1) {
          stringy = "00" + stringy;
        } else if (stringy.length == 2) {
          stringy = "0" + stringy;
        }
        return {
          text: textString,
          spriteUrl: "http://sprites.pokecheck.org/i/"+stringy+".gif"
        }
    });    
  });
}

/*
* Return a text string when the battle starts.
* Stores the player's Slack username and what channel the battle is in,
* and chooses a Pokemon for the NPC from the original 151.
*/
module.exports.startBattle = function(slackData) {
  var textString = "OK {name}, I'll battle you! ".replace("{name}", slackData.user_name),
      dex_no = Math.ceil(Math.random() * 151);
  return stateMachine.newBattle(slackData.user_name, slackData.channel_name)
  .then(function() {
    return module.exports.npcChoosePokemon(dex_no); 
  })
  .then(function(pkmnChoice){
    return {
      text: textString + '\n' + pkmnChoice.text,
      spriteUrl: pkmnChoice.spriteUrl
    }
  })
}

module.exports.endBattle = function() {
  return stateMachine.endBattle();
}

var effectivenessMessage = function(mult) {
  switch(mult) {
    case 0:
      return "It doesn't have an effect. ";
      break;
    case 0.5:
    case 0.25:
      return "It's not very effective... ";
      break;
    case 1:
      return " ";
      break;
    case 2:
    case 4:
      return "It's super effective! ";
      break;
    default:
      return " ";
      break;
  }
}

/*
* Helper function for using one of the user's pokemon's move.
* First check to see if the move is among the allowed moves,
* calculate the type effectiveness, calculate the damage,
* and then return a message.
*/
var useMoveUser = function(moveName) {
  var textString = "You used {mvname}! {effctv}",
      textStringDmg = "It did {dmg} damage, leaving me with {hp}HP!";
  return stateMachine.getUserAllowedMoves()
  .then(function(moves){
    if(moves.indexOf(moveName) !== -1) {
      return stateMachine.getSingleMove(moveName);
    } else {
      throw new Error("Your pokemon doesn't know that move.");
    }
  })
  .then(function(moveData){
    textString = textString.replace("{mvname}", moveName);
    return stateMachine.getNpcPkmnTypes()
    .then(function(types){
      return pokeapi.getAttackMultiplier(moveData.type, types[0], types[1])
      .then(function(multiplier){
        //do damage
        var totalDamage = Math.ceil( (moveData.power / 5) * multiplier )
        return stateMachine.doDamageToNpc(totalDamage)
        .then(function(hpRemaining){
          if(parseInt(hpRemaining, 10) <= 0) {
            return stateMachine.endBattle()
            .then(function(){
              return "You Beat Me!";
            })
          }
          textString = textString.replace("{effctv}", effectivenessMessage(multiplier));
          textStringDmg = textStringDmg.replace("{dmg}", totalDamage);
          textStringDmg = textStringDmg.replace("{hp}", hpRemaining);
          if(multiplier == 0)
            return textString;
          return textString + textStringDmg; 
        })
      });
    })
  })
}

/*
* Helper function for using one of the NPC's pokemon's move.
* First check to see if the move is among the allowed moves,
* calculate the type effectiveness, calculate the damage,
* and then return a message.
*/
var useMoveNpc = function() {
  var textString = "I used {mvname}! {effctv}",
      textStringDmg = "It did {dmg} damage, leaving you with {hp}HP!",
      randMove = Math.floor(Math.random() * 4);
  return stateMachine.getNpcAllowedMoves()
  .then(function(moves){
    textString = textString.replace("{mvname}", moves[randMove]);
    return stateMachine.getSingleMove(moves[randMove]);
  })
  .then(function(moveData){
    return stateMachine.getUserPkmnTypes()
    .then(function(types){
      return pokeapi.getAttackMultiplier(moveData.type, types[0], types[1])
      .then(function(multiplier){
        //do damage
        var totalDamage = Math.ceil( (moveData.power / 5) * multiplier )
        return stateMachine.doDamageToUser(totalDamage)
        .then(function(hpRemaining){
          if(parseInt(hpRemaining, 10) <= 0) {
            return stateMachine.endBattle()
            .then(function(){
              return "You Lost!";
            })
          }
          textString = textString.replace("{effctv}", effectivenessMessage(multiplier));
          textStringDmg = textStringDmg.replace("{dmg}", totalDamage);
          textStringDmg = textStringDmg.replace("{hp}", hpRemaining);
          if(multiplier == 0)
            return textString;
          return textString + textStringDmg; 
        })
      });
    })
  })
}

/*
* When the user uses a move, calculate the results of the user's turn,
* then the NPC's turn. If either one of them ends the battle, don't show
* the other result.
*/
module.exports.useMove = function(moveName) {
  return Q.all([useMoveNpc(), useMoveUser(moveName)])
  .then(function(results){
    if(results[1] === "You Beat Me!") {
      return results[1];
    } else if (results[0] === "You Lost!") {
      return results[0];
    } else {
      return results[1] + "\n" + results[0];
    }
  })
}