const DB = {
  allMonsters: [],
  allAnimations: {},
  monsters: {},
  shapes: {},
  elements: {},
  techniques: {},
  statusEffects: {},
};

const ElementType = {
  aether: 'aether',
  wood: 'wood',
  fire: 'fire',
  earth: 'earth',
  metal: 'metal',
  water: 'water',

  /* lightning: 'lightning',
  frost: 'frost',
  venom: 'venom',
  //vermin: 'vermin',
  cosmic: 'cosmic',
  battle: 'battle',
  psionic: 'psionic',
  darkness: 'darkness',
  heaven: 'heaven',

  combineTypes(typeA, typeB) {
    if (typeA === ElementType.earth & typeB === ElementType.fire) {
      return ElementType.lightning;
    }
    if (typeA === ElementType.earth & typeB === ElementType.water) {
      return ElementType.frost;
    }
    if (typeA === ElementType.earth & typeB === ElementType.wood) {
      return ElementType.venom;
    }
    // if (typeA === ElementType.earth & typeB === ElementType.metal) {
    //   return ElementType.vermin;
    // }
    if (typeA === ElementType.fire && typeB === ElementType.water) {
      return ElementType.cosmic;
    }
  } */
};
const ElementTypeColor = {
  [ElementType.aether]: 'rgba(255, 255, 255, 1)',
  [ElementType.wood]: '#3ca6a6',
  [ElementType.fire]: '#ca3c3c',
  [ElementType.earth]: '#eac93c',
  [ElementType.metal]: '#e4e4e4',
  [ElementType.water]: '#3c3c3c',
};
const TasteWarm = {
  tasteless: 'tasteless',
  peppy: 'peppy',
  salty: 'salty',
  hearty: 'hearty',
  zesty: 'zesty',
  refined: 'refined',
};
const TasteCold = {
  tasteless: 'tasteless',
  mild: 'mild',
  sweet: 'sweet',
  soft: 'soft',
  flakey: 'flakey',
  dry: 'dry',
};
const TechniqueRange = {
  melee: 'melee',
  touch: 'touch',
  ranged: 'ranged',
  reach: 'reach',
  reliable: 'reliable',
};
const StatusType = {
  melee: 'melee',
  armour: 'armour',
  ranged: 'ranged',
  dodge: 'dodge',
  speed: 'speed',
};
const StatusEffectType = {
  blinded: 'blinded',
  burn: 'burn',
  chargedup: 'chargedup',
  charging: 'charging',
  confused: 'confused',
  diehard: 'diehard',
  dozing: 'dozing',
  elementalshield: 'elementalshield',
  eliminated: 'eliminated',
  enraged: 'enraged',
  exhausted: 'exhausted',
  faint: 'faint',
  feedback: 'feedback',
  festering: 'festering',
  flinching: 'flinching',
  focused: 'focused',
  grabbed: 'grabbed',
  hardshell: 'hardshell',
  harpooned: 'harpooned',
  lifeleech: 'lifeleech',
  lockdown: 'lockdown',
  noddingoff: 'noddingoff',
  poison: 'poison',
  prickly: 'prickly',
  recover: 'recover',
  slow: 'slow',
  sniping: 'sniping',
  softened: 'softened',
  stuck: 'stuck',
  tired: 'tired',
  wasting: 'wasting',
  wild: 'wild',
};

class State {
  money = 0;
  monsters = [];

  inventory = [];

  partyMonsters = [];

  activeMonster = null;
  activeTechnique = null;

  turn = 0;
  currentArea = null;

  enemy = {
    monster: null,
  };
};

class Monster {
  #level = 1;
  #hp = 0;

  exp = 1;

  tasteWarm = TasteWarm.tasteless;
  tasteCold = TasteCold.tasteless;

  gender = '';

  heldItem = null;
  statusEffect = '';

  statusModifier = {
    hp: 0,
    melee: 0,
    armour: 0,
    ranged: 0,
    dodge: 0,
    speed: 0,
  };

  experienceModifier = 1;
  moneyModifier = 1;

  constructor (slug) {
    this.slug = slug;

    const tasteWarm = Object.keys(TasteWarm).slice(1);
    this.tasteWarm = tasteWarm[Math.floor(Math.random() * tasteWarm.length)];
    const tasteCold = Object.keys(TasteCold).slice(1);
    this.tasteCold = tasteCold[Math.floor(Math.random() * tasteCold.length)];

    this.hp = this.status.hp;

    const possibleGenders = DB.monsters[this.slug].possible_genders;
    this.gender = possibleGenders[Math.floor(Math.random() * possibleGenders.length)]
  }

  get shape () {
    for (const shapeData of DB.shapes) {
      if (shapeData.slug === DB.monsters[this.slug].shape) {
        return shapeData;
      }
    }
  }

  get types () {
    return DB.monsters[this.slug].types;
  }

  get moveset () {
    return DB.monsters[this.slug].moveset;
  }

  get evolutions () {
    return DB.monsters[this.slug].evolutions;
  }

  get level () {
    return this.#level;
  }

  set level (level) {
    const statusPreLevelUp = this.status;
    const hpPreLevelUp = this.hp;

    this.#level = level;

    const statusPostLevelUp = this.status;

    this.hp = statusPostLevelUp.hp - (statusPreLevelUp.hp - hpPreLevelUp);

    if (this.exp < this.getExperienceRequired(-1)) {
      this.exp = this.getExperienceRequired(-1);
    }
  }

  get hp () {
    return this.#hp;
  }

  set hp (hp) {
    this.#hp = Math.max(0, Math.min(hp, this.status.hp));
  }

  get name () {
    return slugToName(this.slug);
  }

  canLevelUp () {
    return this.exp >= this.getExperienceRequired();
  }

  levelUp () {
    while (this.canLevelUp()) {
      this.level++;
    }
  }

  getExperienceRequired (levelOffset = 0) {
    return Math.max(
      Math.pow(this.level + levelOffset, 3),
      1
    );
  }

  getPossibleEvolutions () {
    // return this.evolutions.filter((evolution) => this.level >= evolution.at_level && (!evolution.item || this.heldItem === evolution.item));
    return this.evolutions.filter((evolution) => evolution.path === 'standard' && this.level >= evolution.at_level);
  }

  canEvolve () {
    return this.getPossibleEvolutions().length > 0;
  }

  evolve () {
    const evolution = this.getPossibleEvolutions()[0];

    const statusPreEvolve = this.status;
    const hpPreEvolve = this.hp;

    this.slug = evolution.monster_slug;

    const statusPostEvolve = this.status;

    this.hp = statusPostEvolve.hp - (statusPreEvolve.hp - hpPreEvolve);
  }

  getTasteStatusModifier (statusName, baseStatus) {
    let positive = 0;
    let negative = 0;

    let isPositive = false;
    let isNegative = false;
    if (statusName === 'melee') {
      isPositive = this.tasteWarm === TasteWarm.salty;
      isNegative = this.tasteCold === TasteCold.sweet;
    }
    else if (statusName === 'armour') {
      isPositive = this.tasteWarm === TasteWarm.hearty;
      isNegative = this.tasteCold === TasteCold.soft;
    }
    else if (statusName === 'ranged') {
      isPositive = this.tasteWarm === TasteWarm.zesty;
      isNegative = this.tasteCold === TasteCold.flakey;
    }
    else if (statusName === 'dodge') {
      isPositive = this.tasteWarm === TasteWarm.refined;
      isNegative = this.tasteCold === TasteCold.dry;
    }
    else if (statusName === 'speed') {
      isPositive = this.tasteWarm === TasteWarm.peppy;
      isNegative = this.tasteCold === TasteCold.mild;
    }

    if (isPositive) {
      positive = baseStatus * 10 / 100;
    }
    if (isNegative) {
      negative = baseStatus * 10 / 100;
    }

    return Math.floor(positive) - Math.floor(negative);
  }

  get status () {
    const multiplier = this.level + 7;
    let hp = (this.shape.hp * multiplier) + this.statusModifier.hp;
    let melee = (this.shape.melee * multiplier) + this.statusModifier.melee;
    let armour = (this.shape.armour * multiplier) + this.statusModifier.armour;
    let ranged = (this.shape.ranged * multiplier) + this.statusModifier.ranged;
    let dodge = (this.shape.dodge * multiplier) + this.statusModifier.dodge;
    let speed = (this.shape.speed * multiplier) + this.statusModifier.speed;

    // Tastes
    melee += this.getTasteStatusModifier('melee', melee);
    armour += this.getTasteStatusModifier('armour', melee);
    ranged += this.getTasteStatusModifier('ranged', melee);
    dodge += this.getTasteStatusModifier('dodge', melee);
    speed += this.getTasteStatusModifier('speed', melee);

    return {
      hp,
      melee,
      armour,
      ranged,
      dodge,
      speed,
    };
  }

  setStatusModifier (statusType, newAbsoluteValue) {
    this.statusModifier[statusType] = newAbsoluteValue - this.status[statusType];
  }
  resetStatusModifier () {
    for (const m in this.statusModifier) {
      this.statusModifier[m] = 0;
    }
  }
};

class Technique {
  #accuracy = 0;
  #potency = 0;
  #power = 0;

  combatEffects = [];

  constructor (slug) {
    this.slug = slug;

    this.resetToBase();
  }

  get types () {
    return DB.techniques[this.slug].types;
  }

  get range () {
    return DB.techniques[this.slug].range;
  }

  get animation () {
    return DB.techniques[this.slug].animation;
  }

  get sfx () {
    return DB.techniques[this.slug].sfx;
  }

  get effects () {
    return DB.techniques[this.slug].effects;
  }

  get accuracy () {
    return this.#accuracy;
  }
  set accuracy (accuracy) {
    this.#accuracy = accuracy;
  }

  get potency () {
    return this.#potency;
  }
  set potency (potency) {
    this.#potency = potency;
  }

  get power () {
    return this.#power;
  }
  set power (power) {
    this.#power = power;
  }

  get base () {
    const accuracy = DB.techniques[this.slug].accuracy;
    const potency = DB.techniques[this.slug].potency;
    const power = DB.techniques[this.slug].power;

    return {
      accuracy,
      potency,
      power,
    };
  }

  resetToBase () {
    this.accuracy = this.base.accuracy;
    this.potency = this.base.potency;
    this.power = this.base.power;
  }
}

class Item {}

class TechniqueEffect {
  constructor (str) {
    this.recipient = str.split(',')[1];
    this.application = str.split(' ')[0];
    this.type = str.split(',')[0].split(' ')[1].split('_')[0];
    this.effect = str.split(',')[0].split(' ')[1].split('_')[1];
  }
}

class StatusEffect {
  turnsLeft = 0;

  constructor (slug) {
    this.slug = slug;

    if (['recover', 'lifeleech'].includes(this.slug)) {
      this.turnsLeft = 1;
    }
    else if (['charging'].includes(this.slug)) {
      this.turnsLeft = 2;
    }
    else if (this.category === 'positive') {
      this.turnsLeft = Math.ceil(Math.random() * 6) + 4;
    }
    else if (this.category === 'negative') {
      this.turnsLeft = Math.ceil(Math.random() * 3) + 2;
    }
    else {
      this.turnsLeft = Math.ceil(Math.random() * 3) + 2;
    }
  }

  get effects () {
    return DB.statusEffects[this.slug].effects;
  }

  get category () {
    return DB.statusEffects[this.slug].category;
  }

  get name () {
    return slugToName(this.slug);
  }

  get status () {
    const status = {};

    const statusChangeKeys = Object.keys(DB.statusEffects[this.slug]).filter((key) => key.startsWith('stat'));
    for (const key of statusChangeKeys) {
      status[key.replace('stat', '')] = DB.statusEffects[this.slug][key];
    }

    return status;
  }
}

function simpleDamageMultiplier (techniqueTypes, targetTypes) {
  let multiplier = 1;

  for (const techniqueType of techniqueTypes) {
    if (techniqueType === ElementType.aether) {
      continue;
    }

    for (const targetType of targetTypes) {
      if (targetType === ElementType.aether) {
        continue;
      }

      multiplier *= DB.elements[techniqueType].types.find((type) => type.against === targetType).multiplier;
    }
  }

  return Math.max(0.25, Math.min(multiplier, 4));
}
function simpleDamageCalculation (technique, user, target) {
  if (technique.power === 0) {
    return 0;
  }

  let userBaseStrength = user.level + 7;
  let userStrength = 1;
  let targetResist = 1;

  if (technique.range === TechniqueRange.melee) {
    userStrength = userBaseStrength * user.status.melee;
    targetResist = target.status.armour;
  }
  else if (technique.range === TechniqueRange.touch) {
    userStrength = userBaseStrength * user.status.melee;
    targetResist = target.status.dodge;
  }
  else if (technique.range === TechniqueRange.ranged) {
    userStrength = userBaseStrength * user.status.ranged;
    targetResist = target.status.dodge;
  }
  else if (technique.range === TechniqueRange.reach) {
    userStrength = userBaseStrength * user.status.ranged;
    targetResist = target.status.armour;
  }
  else if (technique.range === TechniqueRange.reliable) {
    userStrength = userBaseStrength;
    targetResist = 1;
  }

  const multiplier = simpleDamageMultiplier(technique.types, target.types);
  const moveStrength = technique.power * multiplier;
  const damage = Math.floor((userStrength * moveStrength) / targetResist);

  return Math.max(damage, 1);
}

function calculateAwardedExperience (playerMonster, enemyMonster) {
  return Math.max(
    Math.floor(
      enemyMonster.getExperienceRequired(-1) / enemyMonster.level * enemyMonster.experienceModifier / playerMonster.level
    ),
    1
  );
}

async function fetchMonster (slug) {
  if (! DB.monsters[slug]) {
    DB.monsters[slug] = await fetch(`/modules/tuxemon/mods/tuxemon/db/monster/${slug}.json`).then((response) => response.json());
  }

  return new Monster(slug);
}
async function fetchTechnique (slug) {
  if (! DB.techniques[slug]) {
    DB.techniques[slug] = await fetch(`/modules/tuxemon/mods/tuxemon/db/technique/${slug}.json`).then((response) => response.json());
  }

  return new Technique(slug);
}
async function fetchStatusEffect (slug) {
  if (! DB.statusEffects[slug]) {
    DB.statusEffects[slug] = await fetch(`/modules/tuxemon/mods/tuxemon/db/technique/status_${slug}.json`).then((response) => response.json());
  }

  return new StatusEffect(slug);
}

function standardizeColor (color) {
  var ctx = document.createElement('canvas').getContext('2d');
  ctx.fillStyle = color;

  return ctx.fillStyle;
}
function mixColors(...colors) {
  let r = 0;
  let g = 0;
  let b = 0;

  for (const color of colors) {
    const [cr, cg, cb] = color.match(/\w\w/g).map((c) => parseInt(c, 16));

    r += cr;
    g += cg;
    b += cb;
  }

  r = r / colors.length;
  g = g / colors.length;
  b = b / colors.length;

  return `rgb(${r}, ${g}, ${b})`;
}

function slugToName (slug) {
  return slug.split('_').map((item) => item.charAt(0).toUpperCase() + item.slice(1)).join(' ');
}

(async function () {
  DB.allMonsters = await fetch('/db/all-monsters.json').then((response) => response.json());
  DB.allAnimations = await fetch('/db/animations.json').then((response) => response.json());
  DB.shapes = await fetch('/modules/tuxemon/mods/tuxemon/db/shape/shapes.json').then((response) => response.json());
  for (const element of Object.keys(ElementType)) {
    DB.elements[element] = await fetch(`/modules/tuxemon/mods/tuxemon/db/element/${element}.json`).then((response) => response.json());
  }

  const state = new State();
  state.enemy.monster = await fetchMonster('grintot');

  state.partyMonsters = [
    await fetchMonster('corvix'),
    await fetchMonster('lunight'),
    await fetchMonster('prophetoise'),
    await fetchMonster('drashimi'),
    await fetchMonster('glombroc'),
    await fetchMonster('uneye'),
    await fetchMonster('nostray'),
    await fetchMonster('dragarbor'),
  ];
  state.activeMonster = state.partyMonsters[0];
  state.activeTechnique = await fetchTechnique(state.activeMonster.moveset[0].technique);

  const templatePartyMonster = document.querySelector('#tpl___party__monster').innerHTML;
  const templateBattleMonster = document.querySelector('#tpl___battle__monster').innerHTML;
  const templatePopup = document.querySelector('#tpl___popup').innerHTML;
  const templateMovesetList = document.querySelector('#tpl___moveset__list').innerHTML;
  const templateMovesetItem = document.querySelector('#tpl___moveset__item').innerHTML;

  const party = document.querySelector('#party');
  const money = document.querySelector('#money');

  const battle = document.querySelector('#battle');
  const battleEnemy = document.querySelector('#battle__enemy');
  const battlePlayer = document.querySelector('#battle__player');

  const UI = {
    activeMonster: null,

    enemyImg: null,
    damageHighlightClickDuration: 0.1,
    damageHighlightClickTimeout: null,
    imgClickDuration: 0.1,
    damageClickTimeout: null,

    damageAnimationIsRunning: false,
    damageAnimationNumber: 0,

    getTemplate (template) {
      var tpl = document.createElement('div');
      tpl.innerHTML = template.trim();

      return tpl.firstChild;
    },

    setExp (monster, parentNode) {
      const expBar = parentNode.querySelector('.exp-bar');
      const expText = parentNode.querySelector('.exp-text');

      const expToNextLevel = monster.getExperienceRequired() - monster.getExperienceRequired(-1);
      const currentExp = monster.exp - monster.getExperienceRequired(-1);
      expBar.style.width = (currentExp / expToNextLevel) * 100 + '%';
      expText.textContent = monster.exp + ' / ' + monster.getExperienceRequired();
    },

    setHp (monster, parentNode) {
      const hpBar = parentNode.querySelector('.hp-bar');
      const hpText = parentNode.querySelector('.hp-text');

      const percentHp = (monster.hp / monster.status.hp) * 100;
      if (percentHp > 60) {
        hpBar.style.backgroundColor = 'green';
      } else if (percentHp > 15) {
        hpBar.style.backgroundColor = 'rgb(240, 240, 100)';
      } else {
        hpBar.style.backgroundColor = 'red';
      }

      hpBar.style.width = percentHp + '%';
      hpText.textContent = monster.hp + ' / ' + monster.status.hp;
    },

    async createDamage (event, damage) {
      const damageNode = document.createElement('div');
      damageNode.classList.add('damage');
      damageNode.textContent = damage;

      const damageMultiplier = simpleDamageMultiplier(state.activeTechnique.types, state.enemy.monster.types);
      damageNode.style.fontSize = damageMultiplier*2 + 'rem';

      damageNode.style.top = event.pageY - battleEnemy.offsetTop + (Math.random() * 40 - 20);
      damageNode.style.left = event.pageX - battleEnemy.offsetLeft + (Math.random() * 40 - 20);

      damageNode.style.color = mixColors(...state.activeTechnique.types.map((type) => standardizeColor(ElementTypeColor[type])));

      const damageNodeDuration = 2;
      damageNode.style.animationDuration = damageNodeDuration + 's';

      battleEnemy.appendChild(damageNode);
      setTimeout(() => damageNode.remove(), (damageNodeDuration * 1000) - 500);

      this.enemyImg.classList.add('damaged');
      clearTimeout(this.damageHighlightClickTimeout);
      this.damageHighlightClickTimeout = setTimeout(() => this.enemyImg.classList.remove('damaged'), this.damageHighlightClickDuration * 1000);

      var enemyAnimation = battleEnemy.querySelector('.battle__monster-sprite__animation');
      if (!this.damageAnimationIsRunning && state.activeTechnique.animation && DB.allAnimations[state.activeTechnique.animation]) {
        this.damageAnimationIsRunning = true;

        const damageAnimationLoop = () => {
          enemyAnimation.src = `/modules/tuxemon/mods/tuxemon/animations/technique/${state.activeTechnique.animation}_${("00" + this.damageAnimationNumber).slice(-2)}.png`;
          enemyAnimation.style.top = event.clientY - (enemyAnimation.clientHeight / 2);
          enemyAnimation.style.left = event.clientX - (enemyAnimation.clientWidth / 2);
          // console.log(enemyAnimation.src);

          this.damageAnimationNumber++;

          if (this.damageAnimationNumber >= DB.allAnimations[state.activeTechnique.animation].length) {
            this.damageAnimationIsRunning = false;
            this.damageAnimationNumber = 0;
            enemyAnimation.src = '';
            return;
          }

          setTimeout(() => requestAnimationFrame(damageAnimationLoop), 50);
        };

        requestAnimationFrame(damageAnimationLoop);

        // sfx
        /* let sfx = state.activeTechnique.sfx.substr(4);
        const audio = new Audio(`/modules/tuxemon/mods/tuxemon/sounds/technique/${sfx}.ogg`);
        audio.play(); */
      }
    },

    setBattleMonster (monster, where) {
      let battleMonster = document.createElement('div');
      battleMonster.innerHTML = templateBattleMonster.trim();
      battleMonster = battleMonster.firstChild;

      battleMonster.querySelector('.battle__monster-info__name').textContent = monster.name;
      battleMonster.querySelector('.battle__monster-info__gender').textContent = monster.gender === 'male' ? '♂' : monster.gender === 'female' ? '♀' : '⚲';
      battleMonster.querySelector('.battle__monster-info__level').textContent = monster.level;
      battleMonster.querySelector('.battle__monster-info__status').innerHTML = UI.createStatusEffectIcon(monster.statusEffect);
      battleMonster.querySelector('.battle__monster-img').src = `/modules/tuxemon/mods/tuxemon/gfx/sprites/battle/${monster.slug}-front.png`;

      UI.setHp(monster, battleMonster.querySelector('.hp'));

      if (where === 'player') {
        UI.setExp(monster, battleMonster.querySelector('.exp'));
        battleMonster.querySelector('.battle__monster-technique').addEventListener('click', UI.openMovesetSelection);

        battleMonster.classList.add('battle__monster--player');
        battlePlayer.querySelector('.battle__monster') && battlePlayer.removeChild(battlePlayer.querySelector('.battle__monster'));
        battlePlayer.appendChild(battleMonster);

        UI.setActiveTechnique();
      } else {
        battleMonster.classList.add('battle__monster--enemy');

        this.enemyImg = battleMonster.querySelector('.battle__monster-img');
        this.enemyImg.style.transitionDuration = this.damageHighlightClickDuration + 's';

        const previousBattleMonster = battleEnemy.querySelector('.battle__monster');
        if (previousBattleMonster) {
          this.enemyImg.classList = previousBattleMonster.querySelector('.battle__monster-img').classList;

          battleEnemy.removeChild(previousBattleMonster);
        }

        battleEnemy.appendChild(battleMonster);
      }
    },

    setEnemyMonster () {
      UI.setBattleMonster(state.enemy.monster, 'enemy');
    },

    setActiveMonster () {
      UI.setBattleMonster(state.activeMonster, 'player');
    },

    setActiveTechnique () {
      battlePlayer.querySelector('.battle__monster-technique').innerHTML =
        slugToName(state.activeTechnique.slug) + ' &nbsp; '
          + state.activeTechnique.types.map((type) => UI.createElementTypeIcon(type)).join('');
    },

    async chooseActiveTechnique () {
      let activeMoveIndex = 0;
      while ((await fetchTechnique(state.activeMonster.moveset[activeMoveIndex].technique)).power === 0) {
        activeMoveIndex++;
      }
      state.activeTechnique = await fetchTechnique(state.activeMonster.moveset[activeMoveIndex].technique);

      UI.setActiveTechnique();
    },

    async openMovesetSelection () {
      const popup = UI.createPopup();

      const movesetList = UI.getTemplate(templateMovesetList);
      for (const move of state.activeMonster.moveset) {
        const technique = await fetchTechnique(move.technique);
        const movesetItem = UI.getTemplate(templateMovesetItem);

        movesetItem.querySelector('.moveset__item__name').textContent = slugToName(technique.slug);
        movesetItem.querySelector('.moveset__item__type').innerHTML = technique.types.map((type) => UI.createElementTypeIcon(type)).join('');
        movesetItem.querySelector('.moveset__item__power').innerHTML = technique.power;
        movesetItem.querySelector('.moveset__item__level').innerHTML = move.level_learned;

        movesetItem.addEventListener('click', () => {
          if (movesetItem.getAttribute('disabled')) {
            return false;
          }

          state.activeTechnique = technique;
          UI.setActiveTechnique();

          popup.remove();
        });

        if (state.activeMonster.level < move.level_learned) {
          movesetItem.setAttribute('disabled', true);
        }

        movesetList.appendChild(movesetItem);
      }

      popup.querySelector('.popup').appendChild(movesetList);
      document.body.appendChild(popup);
    },

    async createNewEnemyMonster () {
      state.enemy.monster = await fetchMonster(DB.allMonsters[Math.floor(Math.random() * DB.allMonsters.length)]);
      state.enemy.monster.level = Math.ceil(Math.random() * state.activeMonster.level);
      // state.enemy.monster.experienceModifier = state.enemy.monster.level;
      state.enemy.monster.moneyModifier = state.enemy.monster.level;
      UI.setEnemyMonster();
    },

    createElementTypeIcon (type) {
      var img = document.createElement('img');
      img.src = `/modules/tuxemon/mods/tuxemon/gfx/ui/icons/element/${type}_type.png`;
      img.title = slugToName(type);

      return img.outerHTML;
    },

    createStatusEffectIcon (statusEffect) {
      if (!statusEffect) return '';

      var img = document.createElement('img');
      img.src = `/modules/tuxemon/mods/tuxemon/gfx/ui/icons/status/icon_${statusEffect.slug}.png`;
      img.title = statusEffect.name;

      return img.outerHTML;
    },

    createPopup () {
      const popup = UI.getTemplate(templatePopup);
      popup.addEventListener('click', ({ target }) => target === popup && popup.remove());

      return popup;
    },

    openPartyMenu () {
      const popup = UI.createPopup();

      const party = document.createElement('div');
      party.id = 'party';
      for (const monster of state.partyMonsters) {
        const partyMonster = UI.getTemplate(templatePartyMonster);

        partyMonster.dataset.slug = monster.slug;
        partyMonster.querySelector('img').src = `/modules/tuxemon/mods/tuxemon/gfx/sprites/battle/${monster.slug}-front.png`;

        partyMonster.addEventListener('click', async (event) => {
          let target = event.target;
          while (target.parentNode.id !== 'party') {
            target = target.parentNode;
          }

          state.activeMonster = state.partyMonsters[Array.prototype.indexOf.call(document.querySelector('#party').children, target)];
          await UI.chooseActiveTechnique();
          UI.setActiveMonster();

          popup.remove();
        });

        party.appendChild(partyMonster);
      }

      popup.querySelector('.popup').appendChild(party);
      document.body.appendChild(popup);
    },

    openInventoryMenu () {
      const popup = UI.createPopup();

      const inventory = document.createElement('div');
      inventory.id = 'inventory';
      for (const item of state.inventory) {
      }

      popup.querySelector('.popup').appendChild(inventory);
      document.body.appendChild(popup);
    },
  };

  const Game = {
    async useTechnique(technique, user, target) {
      let statusEffects = [];
      let combatEffects = [];

      for (const effect of technique.effects) {
        if (effect.includes('status_')) {
          statusEffects.push(new TechniqueEffect(effect));
        }
        else if (!['damage', 'splash', 'area'].includes(effect)) {
          combatEffects.push(effect);
        }
      }

      for (const effect of statusEffects) {
        let recipient;

        if (effect.recipient === 'user') {
          recipient = user;
        } else {
          recipient = target;
        }

        if (effect.type === 'status') {
          if (effect.application === 'give') {
            if (recipient.statusEffect) {
              continue;
            }

            const potency = Math.random();
            const success = technique.potency >= potency;
            if (success) {
              recipient.statusEffect = await fetchStatusEffect(effect.effect);
            }
          }
          else if (effect.application === 'remove') {
            if (recipient.statusEffect.slug === effect.effect) {
              recipient.statusEffect = '';
            }
          }
        }
      }

      technique.combatEffects = combatEffects;
    },

    async applyStatusEffect (affectedMonster, opposingMonster) {
      if (!affectedMonster.statusEffect) {
        return;
      }

      if (! (affectedMonster.statusEffect instanceof StatusEffect)) {
        return;
      }

      if (affectedMonster.statusEffect.slug === 'poison' || affectedMonster.statusEffect.slug === 'burn') {
        const statusEffectDamage = Math.floor(affectedMonster.status.hp / 8);
        affectedMonster.hp -= statusEffectDamage;

        UI.createDamage(clickEvent, statusEffectDamage);
      }

      else if (affectedMonster.statusEffect.slug === 'recover') {
        const statusEffectHeal = Math.floor(affectedMonster.status.hp / 16);
        affectedMonster.hp += statusEffectHeal;
      }

      else if (affectedMonster.statusEffect.slug === 'lifeleech') {
        const statusEffectLeech = Math.floor(affectedMonster.status.hp / 16);
        affectedMonster.hp -= statusEffectLeech;
        opposingMonster.hp += statusEffectLeech;

        UI.createDamage(clickEvent, statusEffectLeech);
      }

      else if (affectedMonster.statusEffect.slug === 'charging') {
        turnEndPhaseEvents.push(async () => {
          if (affectedMonster.statusEffect.turnsLeft === 0) {
            affectedMonster.statusEffect = await fetchStatusEffect('chargedup');
          }
        });
      }

      else if (affectedMonster.statusEffect.effects.includes('statchange')) {
        affectedMonster.resetStatusModifier();

        for (const statusType in affectedMonster.statusEffect.status) {
          const statusChange = affectedMonster.statusEffect.status[statusType];

          const modifiedValue = Math.floor(eval(`${affectedMonster.status[statusType]} ${statusChange.operation} ${statusChange.value}`));
          affectedMonster.setStatusModifier(statusType, modifiedValue);
        }
      }

      affectedMonster.statusEffect.turnsLeft--;
      turnEndPhaseEvents.push(() => {
        if (affectedMonster.statusEffect.turnsLeft === 0) {
          affectedMonster.statusEffect = null;
          affectedMonster.resetStatusModifier();
        }
      });
    },

    applyTechniqueEffect (technique, user, target) {
      for (const effect of technique.combatEffects) {
        if (effect === 'money') {
          state.money += Math.floor(Math.random() * target.level);
        }
      }

      // modify technique stats
      if (user.statusEffect) {
        if (user.statusEffect.slug === 'grabbed') {
          if ([TechniqueRange.ranged, TechniqueRange.reach].includes(technique.range)) {
            technique.potency = technique.base.potency * 0.5;
            technique.power = technique.base.power * 0.5;
          }
        }

        else if (user.statusEffect.slug === 'stuck') {
          if ([TechniqueRange.melee, TechniqueRange.touch].includes(technique.range)) {
            technique.potency = technique.base.potency * 0.5;
            technique.power = technique.base.power * 0.5;
          }
        }

        // remove effect
        if (user.statusEffect.turnsLeft === 0) {
          turnEndPhaseEvents.push(() => {
            technique.resetToBase();
          });
        }
      }
    },
  };

  UI.setActiveMonster();
  UI.setEnemyMonster();

  let clickEvent;
  let turnEndPhaseEvents = [];
  document.querySelector('#battle__enemy').addEventListener('click', async (event) => {
    clickEvent = event;

    const accuracy = Math.random();
    const hit = state.activeTechnique.accuracy >= accuracy;

    if (hit) {
      await Game.useTechnique(state.activeTechnique, state.activeMonster, state.enemy.monster);
    }

    await Game.applyStatusEffect(state.activeMonster, state.enemy.monster);
    await Game.applyStatusEffect(state.enemy.monster, state.activeMonster);

    if (hit) {
      Game.applyTechniqueEffect(state.activeTechnique, state.activeMonster, state.enemy.monster);

      const damage = simpleDamageCalculation(state.activeTechnique, state.activeMonster, state.enemy.monster);
      UI.createDamage(event, damage);

      state.enemy.monster.hp -= damage;
      if (state.enemy.monster.hp <= 0) {
        const faintedMonster = state.enemy.monster;

        await UI.createNewEnemyMonster();

        state.money += faintedMonster.level * faintedMonster.moneyModifier;

        state.activeMonster.exp += calculateAwardedExperience(state.activeMonster, faintedMonster);
        state.activeMonster.levelUp();
        if (state.activeMonster.canEvolve()) {
          await fetchMonster(state.activeMonster.evolutions[0].monster_slug);
          state.activeMonster.evolve();
        }
      }
    } else {
      UI.createDamage(event, 'MISS!');
    }

    UI.setActiveMonster();
    UI.setEnemyMonster();

    UI.setHp(state.enemy.monster, battleEnemy);

    money.textContent = state.money;

    for (const turnEndPhaseEvent of turnEndPhaseEvents) {
      const returnValue = turnEndPhaseEvent();
      if (returnValue instanceof Promise) {
        await returnValue;
      }
    }
    turnEndPhaseEvents = [];
  });

  document.querySelector('#menu__party').addEventListener('click', UI.openPartyMenu);

  document.querySelector('#menu__catch').addEventListener('click', async () => {
    const caughtMonster = new Monster(state.enemy.monster.slug);
    caughtMonster.level = state.enemy.monster.level;

    state.partyMonsters.push(caughtMonster);

    UI.createNewEnemyMonster();
  });

  document.querySelector('#menu__inventory').addEventListener('click', UI.openInventoryMenu);
})();