Cljs following of https://hexlet.org/open_lectures/clojure_rpg/ instructions

core.cljs

(ns rpg.core)

(enable-console-print!)

(def max-lvl 10)

;; lvl(integer) -> att(integer)
;; given lvl calculate attack by formula
;; att = lvl * 2
(defn calc-attack 
  [lvl]
  (* lvl 6))

;; lvl(integer) -> def(integer)
;; given lvl calculate defence by formula
;; def = lvl * 1.5
(defn calc-defense
  [lvl]
  (int (* lvl 1.5)))


;; lvl(integer) -> hp(integer)
;; hp = lvl * 20
(defn calc-hitpoints
  [lvl]
  (* lvl 20))


(defn calc-sides
  [lvl]
  (if (> lvl 5) 4 6))

(defn kill-negative
  [n]
  (if (neg? n) 0 n))

(defn calc-base-damage
  [att def]
  (kill-negative (- att def)))

;; given number of sides roll the dice
;; sides(int) -> roll dice(int)
(defn roll-dice
  [sides]
  (inc (rand-int sides)))

(defn create-character
  [name lvl]
  {:name name
   :lvl lvl
   :att (calc-attack lvl)
   :def (calc-defense lvl)
   :hp (calc-hitpoints lvl)})

(defn real-damage
  [base sides]
  (let [rd (roll-dice sides)
        s (/ sides 2)]
    (cond
      (<= rd s) (int (/ base 2))
      (= rd sides) (* base 2)
      (> rd s) base)))

;;from(character) + to(character)
;; [damage(integer), chracter]
(defn take-damage
  [from to]
  (let [bd (calc-base-damage (:att from) (:def to))
        s (calc-sides (:lvl from))
        rd (real-damage bd s)]
  [rd, (update-in to [:hp] #(- % rd))]))





(defn log-template [a b c]
  (str "Character " a " received " b " damage.
  His new life is " c "."))

(defn print-battle-log
  [damage character]
  (let [name (:name character)
        newhp (:hp character)
        ; no format in cljs, see http://dev.clojure.org/jira/browse/CLJS-324
        s (log-template name damage newhp)]
    (println s)))

(defn print-winner
  [p-hp e-hp]
  (if (<= p-hp 0)
    (println "Enemy won.")
    (println "Player won.")))

(defn game-logic
  [config]
  (loop [player (:player config)
         enemy (:enemy config)
         round 1]
    (if (or (<= (:hp player) 0)
            (<= (:hp enemy) 0))
      (print-winner (:hp player) (:hp enemy))
      (let [pl-en (take-damage player enemy)
            en-pl (take-damage enemy player)]
        (do
          (println (str "Round " round ":"))
          (print-battle-log (pl-en 0) (pl-en 1))
          (print-battle-log (en-pl 0) (en-pl 1))
          (recur (en-pl 1) (pl-en 1) (inc round)))))))


(def player (create-character "Robert" 6))
(def troll (create-character "Troll" 2))
(def big-troll (create-character "Troll" 2))

(def config
  {:player (create-character "John" 3)
   :enemy big-troll})

(game-logic config)