aaa/combat.fnl

(fn get+hit [e] ;TODO use equipment too
  (var n 0)
  (if (and e.weapon e.weapon.+hit) 
    (set n (+ n e.weapon.+hit))) n)

(fn get+dam [e] ;TODO use equipment too
  (var n (or e.+dam 0))
  (if (and e.weapon e.weapon.+dam) 
    (set n (+ n e.weapon.+dam))) n)

(fn get+ac [e]
  (var n 0)
  (set n (+ n (or e.ac 0)))
  (when e.equip
    (each [k v (pairs e.equip)]
      (if (and v v.ac) (set n (+ v.ac)))
      (if (and v v.+ac) (set n (+ v.+ac))))) n)

(fn get+dodge [e]
  (var n 0)
  (when e.equip
    (each [k v (pairs e.equip)]
      (if (and v v.+dodge) (set n (+ v.+dodge))))) n)

(fn calc-hit [e target]
  (let [lvlmod (math.min 48 
                (math.max -48
                  (* 3 (- e.level target.level))))] ;entity level affects hit chance up to a point
    (trace "calc-hit")
    (trace lvlmod)
    (trace (get+hit e))
    (if (chance (+ 50 lvlmod (* (get+hit e) 3))) 
      ;target can have up to 60% dodge chance if hit succeeded
      (if (chance (* (get+dodge target) 2)) false true) 
      false)))

(fn reduce-damage [dam ac]
  ;ac can range from 0 to 40
  (var n (math.floor (* dam (- 1 (/ ac 100)))))
  (if (= n 0) 1 n))

(fn calc-damage [e target]
  ;roll damage for an entities successful hit
  (var base (roll e.attack))
  (if e.weapon
    (set base (roll e.weapon.weapon)))
  (set base (+ base (get+dam e)))
  (set base (reduce-damage base (get+ac target))) base)

(fn evaluate-entity [e]
  (trace (tableprint e))
  ;gives a "score" which we can use for other things
  (var score (* e.maxhp 0.25))
  (trace score)
  ;mainly based on damage possibility
  (set score (+ score (* (. e.attack 1) (. e.attack 2))))
  (trace score)
  ;factor in ai
  (set score (* score (get {:wander 0.5 :confused 1 :hunt 1.5} e.ai 1)))
  (trace score)
  ;general bonus scalar from level
  (set score (* score (+ 1 (* e.level 0.3))))
  (trace score)
  score)

(fn exp-next [n] ;how much experience to get next level
  (or (. [12 32 70 120 300 1200 3200] n) (* n (* n 0.3) 1000)))

(fn exp-value [e]
  (evaluate-entity e))

(fn item-value [o] 
  (var score (* 6 o.level))

  (set score (* score (^ (inc (or o.+hit 0)) 1.7)))
  (set score (* score (^ (inc (or o.+dam 0)) 1.7)))
  (set score (* score (^ (inc (or o.+ac 0)) 1.7)))
  (set score (* score (^ (inc (or o.+dodge 0)) 1.6)))
  (set score (+ score (* o.level 4)))
  (set score (+ score (or o.jack 0)))
  score)


(fn item-print [o v]
  (when o 
  ;prints a colorized detailed item name
  (let [name (or o.name "???")]
    (print name v.x v.y (or o.color 14))
    (var w (# name))
    (if o.weapon
      (let [dice (.. " (" (. o.weapon 1) "d" (. o.weapon 2) ")")]
        (print dice (+ v.x (* w 6)) v.y)
        (set w (+ w (# dice)))))
    (if o.wear
      (let [ac (.. " " o.ac " ")]
        (print ac (+ v.x (* w 6)) v.y)
        (set w (+ w (# ac)))))
    (when o.+ac
      (print (.. " +" o.+ac) (+ v.x (* w 5)) v.y 8)
      (set w (+ w (# (.. " + " o.+ac)))))
    (when o.+dodge
      (print (.. " dg+" o.+dodge) (+ v.x (* w 5)) v.y 5)
      (set w (+ w (# (.. " dg+ " o.+dodge)))))
    (when o.+hit
      (print (.. " +" o.+hit) (+ v.x (* w 5)) v.y 13)
      (set w (+ w (# (.. " + " o.+hit)))))
    (when o.+dam
      (print (.. " +" o.+dam) (+ v.x (* w 5)) v.y 6)
      (set w (+ w (# (.. " + " o.+dam)))))
    )))