2018 day 24 More work

2018/day24/army.go

@@ -1,19 +1,33 @@
 package main
 
+import (
+	"fmt"
+	"strings"
+)
+
+const (
+	ArmyTypeImmune = 1 << iota
+	ArmyTypeInfection
+)
+
 type Army struct {
-	tp         int
-	units      int
-	hp         int
-	immunities []string
-	weaknesses []string
-	damageType string
-	strength   int
-	init       int
+	id          int
+	tp          int
+	units       int
+	hp          int
+	immunities  []string
+	weaknesses  []string
+	damageType  string
+	strength    int
+	init        int
+	target      *Army
+	targettedBy *Army
 }
 
-func NewArmy(inp string, tp int) *Army {
+func NewArmy(inp string, tp, id int) *Army {
 	a := new(Army)
 	a.tp = tp
+	a.id = id
 
 	// Pull the parenthetical out, if one is there
 	var prnth, other string
@@ -43,38 +57,154 @@ func NewArmy(inp string, tp int) *Army {
 	if err != nil {
 		panic(err)
 	}
-  // Now parse out immunities and weaknesses
-  if len(prnth) > 3 {
-    prnth = prnth[1:len(prnth)-1]
-    var inImmune bool 
-    for _, v := range strings.Fields(prnth) {
-      if v == "immune" {
-        inImmune = true
-      } else if v == "weak" {
-        inImmune = false
-      }
-      if v == "to" {
-        continue
-      }
-      if v[len(v)-1] == ';' || v[len(v)-1] == ',' {
-        v = v[:len(v)-1]
-      }
-      if inImmune {
-        a.immunities = append(a.immunities, v)
-      } else {
-        a.weaknesses = append(a.weaknesses, v)
-      }
-    }
-  }
+	// Now parse out immunities and weaknesses
+	if len(prnth) > 3 {
+		prnth = prnth[1 : len(prnth)-1]
+		var inImmune bool
+		for _, v := range strings.Fields(prnth) {
+			if v == "immune" {
+				inImmune = true
+				continue
+			} else if v == "weak" {
+				inImmune = false
+				continue
+			}
+			if v == "to" {
+				continue
+			}
+			if v[len(v)-1] == ';' || v[len(v)-1] == ',' {
+				v = v[:len(v)-1]
+			}
+			if inImmune {
+				a.immunities = append(a.immunities, v)
+			} else {
+				a.weaknesses = append(a.weaknesses, v)
+			}
+		}
+	}
 	return a
 }
 
+func (a *Army) IsImmuneTo(val string) bool {
+	for _, v := range a.immunities {
+		if v == val {
+			return true
+		}
+	}
+	return false
+}
+
+func (a *Army) IsWeakTo(val string) bool {
+	for _, v := range a.weaknesses {
+		if v == val {
+			return true
+		}
+	}
+	return false
+}
+
 func (a *Army) Power() int {
 	return a.units * a.strength
 }
 
+func (a *Army) FindTarget(group []*Army) {
+	var tgt *Army
+	var tgtDmg int
+	for _, v := range group {
+		if v.targettedBy != nil {
+			continue
+		}
+		wrkDmg := a.CalculateDamage(v)
+		if tgt == nil || wrkDmg > tgtDmg {
+			tgt = v
+			tgtDmg = wrkDmg
+		} else if wrkDmg == tgtDmg {
+			if v.Power() > tgt.Power() {
+				tgt = v
+				tgtDmg = wrkDmg
+			} else if v.Power() == tgt.Power() {
+				if v.init > tgt.init {
+					tgt = v
+					tgtDmg = wrkDmg
+				}
+			}
+		}
+		if Debug {
+			var tpTxt string
+			if a.tp == ArmyTypeImmune {
+				tpTxt = "Immune System"
+			} else {
+				tpTxt = "Infection"
+			}
+			fmt.Printf("%s group %d would deal defending group %d %d damage\n", tpTxt, a.id, tgt.id, tgtDmg)
+		}
+	}
+	if tgt != nil {
+		a.target = tgt
+		tgt.targettedBy = a
+	}
+}
+
+func (a *Army) CalculateDamage(b *Army) int {
+	if b.IsWeakTo(a.damageType) {
+		return a.Power() * 2
+	} else if b.IsImmuneTo(a.damageType) {
+		return 0
+	}
+	return a.Power()
+}
+
+func (a *Army) Damage(b *Army) int {
+	var unitsDefeated int
+	dmg := a.CalculateDamage(b)
+	for dmg > 0 {
+		dmg -= b.hp
+		if dmg > 0 && b.units > 0 {
+			b.units--
+			unitsDefeated++
+		}
+	}
+	b.targettedBy = nil
+	return unitsDefeated
+}
+
+func (a *Army) Fight() {
+	if a.target != nil {
+		var tpTxt string
+		if a.tp == ArmyTypeImmune {
+			tpTxt = "Immune System"
+		} else if a.tp == ArmyTypeInfection {
+			tpTxt = "Infection"
+		}
+		dmg := a.Damage(a.target)
+		if Debug {
+			fmt.Printf("%s group %d attacks defending group %d, killing %d units\n", tpTxt, a.id, a.target.id, dmg)
+		}
+	}
+}
+
+func (a Army) String() string {
+	ret := fmt.Sprintf("%d units each with %d hit points ", a.units, a.hp)
+	if len(a.weaknesses) > 0 {
+		ret = ret + fmt.Sprintf("(weaknesses: %s) ", a.weaknesses)
+	}
+	if len(a.immunities) > 0 {
+		ret = ret + fmt.Sprintf("(immunities: %s) ", a.immunities)
+	}
+	ret = ret + fmt.Sprintf("with an attack that does %d %s damage at initiative %d\n",
+		a.strength, a.damageType, a.init,
+	)
+	return ret
+}
+
 // Army Sorting
-type ByPower []Army
-func (b ByPower) Len() int { return len(b) }
+type ByPower []*Army
+
+func (b ByPower) Len() int      { return len(b) }
 func (b ByPower) Swap(i, j int) { b[i], b[j] = b[j], b[i] }
-func (b ByPower) Less(i, j int) { b[i].Power() < b[j].Power() }
+func (b ByPower) Less(i, j int) bool {
+	if b[i].Power() == b[j].Power() {
+		return b[i].init < b[j].init
+	}
+	return b[i].Power() < b[j].Power()
+}