feast/src/game/entity.ts

import { DamageType, Damage, Stats, Vigor, VoreStats, VoreStat, Stat, Vigors, DamageInstance } from './combat'
import { Noun, Pronoun, TextLike, POV, PronounAsNoun, FirstPersonPronouns, SecondPersonPronouns } from './language'
import { LogEntry, LogLine } from './interface'
import { Place, Nowhere } from './world'

export abstract class Entity {
  get name (): Noun {
    if (this.perspective === POV.First) {
      return new PronounAsNoun(FirstPersonPronouns)
    } else if (this.perspective === POV.Second) {
      return new PronounAsNoun(SecondPersonPronouns)
    } else {
      return this.baseName
    }
  }

  get pronouns (): Pronoun {
    if (this.perspective === POV.First) {
      return FirstPersonPronouns
    } else if (this.perspective === POV.Second) {
      return SecondPersonPronouns
    } else {
      return this.basePronouns
    }
  }

  desc: TextLike = "It's a ting."
  perspective: POV = POV.Third
  title: TextLike = "Some thing."
  location: Place

  constructor (public baseName: Noun, public kind: Noun, public basePronouns: Pronoun) {
    this.location = Nowhere
  }
}

export type Resistances = {[key in DamageType]: number}

export abstract class Mortal extends Entity {
  baseResistances: Resistances

  stats: Stats;
  vigors: {[key in Vigor]: number} = {
    [Vigor.Health]: 100,
    [Vigor.Stamina]: 100,
    [Vigor.Resolve]: 100
  }

  constructor (name: Noun, kind: Noun, pronouns: Pronoun, public baseStats: Stats) {
    super(name, kind, pronouns)
    this.stats = Object.keys(Stat).reduce((base: any, key) => { base[key] = baseStats[key as Stat]; return base }, {})
    this.baseResistances = Object.keys(DamageType).reduce((resist: any, key) => { resist[key] = 1; return resist }, {})
    Object.entries(this.maxVigors).forEach(([key, val]) => {
      this.vigors[key as Vigor] = val
    })
  }

  resistanceTo (damageType: DamageType): number {
    return this.baseResistances[damageType]
  }

  get maxVigors (): Readonly<Vigors> {
    return {
      Health: this.stats.Toughness * 10 + this.stats.Power * 5,
      Resolve: this.stats.Willpower * 10 + this.stats.Charm * 5,
      Stamina: this.stats.Speed * 10 + this.stats.Power * 2.5 + this.stats.Charm * 2.5
    }
  }

  get disabled (): boolean {
    return Object.values(this.vigors).some(val => val <= 0)
  }

  effectiveDamage (damage: Damage): Damage {
    const newDamages: DamageInstance[] = []
    damage.damages.forEach(instance => {
      const factor = instance.type === DamageType.Heal ? -1 : 1
      const baseResistance: number = this.resistanceTo(instance.type)
      const resistance = baseResistance * factor
      newDamages.push({
        amount: instance.amount * resistance,
        target: instance.target,
        type: instance.type
      })
    })

    return new Damage(...newDamages)
  }

  takeDamage (damage: Damage): LogEntry {
    // first, we record health to decide if the entity just died
    const startHealth = this.vigors.Health

    damage = this.effectiveDamage(damage)

    damage.damages.forEach(instance => {
      if (instance.target in Vigor) {
        // just deal damage
        this.vigors[instance.target as Vigor] -= instance.amount
      } else if (instance.target in Stat) {
        // drain the stats, then deal damage to match
        const startVigors = this.maxVigors
        this.stats[instance.target as Stat] -= instance.amount
        const endVigors = this.maxVigors

        Object.keys(Vigor).map(vigor => {
          this.vigors[vigor as Vigor] -= startVigors[vigor as Vigor] - endVigors[vigor as Vigor]
        })
      }
    })

    if (this.vigors.Health <= 0 && startHealth > 0) {
      return this.destroy()
    } else {
      return new LogLine()
    }
  }

  toString (): string {
    return this.name.toString()
  }

  abstract destroy (): LogEntry;
}