Added old AI references/rewrite attempt as references

AI references/Old AI rewrite attempt/003_AI_Switch.rb

@@ -0,0 +1,178 @@
+class PokeBattle_AI
+  #=============================================================================
+  # Decide whether the opponent should switch Pokémon
+  #=============================================================================
+  def pbEnemyShouldWithdraw?
+    return pbEnemyShouldWithdrawEx?(false)
+  end
+
+  def pbEnemyShouldWithdrawEx?(forceSwitch)
+    return false if @wildBattler
+    shouldSwitch = forceSwitch
+    batonPass = -1
+    moveType = nil
+    # If Pokémon is within 6 levels of the foe, and foe's last move was
+    # super-effective and powerful
+    if !shouldSwitch && @user.turnCount > 0 && skill_check(AILevel.high)
+      target = @user.pbDirectOpposing(true)
+      if !target.fainted? && target.lastMoveUsed &&
+         (target.level - @user.level).abs <= 6
+        moveData = GameData::Move.get(target.lastMoveUsed)
+        moveType = moveData.type
+        typeMod = pbCalcTypeMod(moveType, target, @user)
+        if PBTypeEffectiveness.superEffective?(typeMod) && moveData.base_damage > 50
+          switchChance = (moveData.base_damage > 70) ? 30 : 20
+          shouldSwitch = (pbAIRandom(100) < switchChance)
+        end
+      end
+    end
+    # Pokémon can't do anything (must have been in battle for at least 5 rounds)
+    if !@battle.pbCanChooseAnyMove?(@user.index) &&
+       @user.turnCount && @user.turnCount>=5
+      shouldSwitch = true
+    end
+    # Pokémon is Perish Songed and has Baton Pass
+    if skill_check(AILevel.high) && @user.effects[PBEffects::PerishSong]==1
+      @user.eachMoveWithIndex do |m,i|
+        next if m.function!="0ED"   # Baton Pass
+        next if !@battle.pbCanChooseMove?(@user.index,i,false)
+        batonPass = i
+        break
+      end
+    end
+    # Pokémon will faint because of bad poisoning at the end of this round, but
+    # would survive at least one more round if it were regular poisoning instead
+    if @user.status==PBStatuses::POISON && @user.statusCount>0 &&
+       skill_check(AILevel.high)
+      toxicHP = @user.totalhp/16
+      nextToxicHP = toxicHP*(@user.effects[PBEffects::Toxic]+1)
+      if @user.hp<=nextToxicHP && @user.hp>toxicHP*2
+        shouldSwitch = true if pbAIRandom(100)<80
+      end
+    end
+    # Pokémon is Encored into an unfavourable move
+    if @user.effects[PBEffects::Encore]>0 && skill_check(AILevel.medium)
+      idxEncoredMove = @user.pbEncoredMoveIndex
+      if idxEncoredMove>=0
+        scoreSum   = 0
+        scoreCount = 0
+        @user.eachOpposing do |b|
+          scoreSum += pbGetMoveScore(@user.moves[idxEncoredMove],b)
+          scoreCount += 1
+        end
+        if scoreCount>0 && scoreSum/scoreCount<=20
+          shouldSwitch = true if pbAIRandom(100)<80
+        end
+      end
+    end
+    # If there is a single foe and it is resting after Hyper Beam or is
+    # Truanting (i.e. free turn)
+    if @battle.pbSideSize(@user.index+1)==1 &&
+       !@user.pbDirectOpposing.fainted? && skill_check(AILevel.high)
+      opp = @user.pbDirectOpposing
+      if opp.effects[PBEffects::HyperBeam]>0 ||
+         (opp.hasActiveAbility?(:TRUANT) && opp.effects[PBEffects::Truant])
+        shouldSwitch = false if pbAIRandom(100)<80
+      end
+    end
+    # Sudden Death rule - I'm not sure what this means
+    if @battle.rules["suddendeath"] && @user.turnCount>0
+      if @user.hp<=@user.totalhp/4 && pbAIRandom(100)<30
+        shouldSwitch = true
+      elsif @user.hp<=@user.totalhp/2 && pbAIRandom(100)<80
+        shouldSwitch = true
+      end
+    end
+    # Pokémon is about to faint because of Perish Song
+    if @user.effects[PBEffects::PerishSong]==1
+      shouldSwitch = true
+    end
+    if shouldSwitch
+      list = []
+      @battle.pbParty(@user.index).each_with_index do |pkmn,i|
+        next if !@battle.pbCanSwitch?(@user.index,i)
+        # If perish count is 1, it may be worth it to switch
+        # even with Spikes, since Perish Song's effect will end
+        if @user.effects[PBEffects::PerishSong]!=1
+          # Will contain effects that recommend against switching
+          spikes = @user.pbOwnSide.effects[PBEffects::Spikes]
+          # Don't switch to this if too little HP
+          if spikes>0
+            spikesDmg = [8,6,4][spikes-1]
+            if pkmn.hp<=pkmn.totalhp/spikesDmg
+              next if !pkmn.hasType?(:FLYING) && !pkmn.hasActiveAbility?(:LEVITATE)
+            end
+          end
+        end
+        # moveType is the type of the target's last used move
+        if moveType && PBTypeEffectiveness.ineffective?(pbCalcTypeMod(moveType,@user,@user))
+          weight = 65
+          typeMod = pbCalcTypeModPokemon(pkmn,@user.pbDirectOpposing(true))
+          if PBTypeEffectiveness.superEffective?(typeMod)
+            # Greater weight if new Pokemon's type is effective against target
+            weight = 85
+          end
+          list.unshift(i) if pbAIRandom(100)<weight   # Put this Pokemon first
+        elsif moveType && PBTypeEffectiveness.resistant?(pbCalcTypeMod(moveType,@user,@user))
+          weight = 40
+          typeMod = pbCalcTypeModPokemon(pkmn,@user.pbDirectOpposing(true))
+          if PBTypeEffectiveness.superEffective?(typeMod)
+            # Greater weight if new Pokemon's type is effective against target
+            weight = 60
+          end
+          list.unshift(i) if pbAIRandom(100)<weight   # Put this Pokemon first
+        else
+          list.push(i)   # put this Pokemon last
+        end
+      end
+      if list.length>0
+        if batonPass>=0 && @battle.pbRegisterMove(@user.index,batonPass,false)
+          PBDebug.log("[AI] #{@user.pbThis} (#{@user.index}) will use Baton Pass to avoid Perish Song")
+          return true
+        end
+        if @battle.pbRegisterSwitch(@user.index,list[0])
+          PBDebug.log("[AI] #{@user.pbThis} (#{@user.index}) will switch with " +
+                      "#{@battle.pbParty(@user.index)[list[0]].name}")
+          return
+        end
+      end
+    end
+    return false
+  end
+
+  #=============================================================================
+  # Choose a replacement Pokémon (called directly from @battle, not part of
+  # action choosing)
+  #=============================================================================
+  def pbDefaultChooseNewEnemy(idxBattler,party)
+    set_up(idxBattler)
+    enemies = []
+    party.each_with_index do |_p,i|
+      enemies.push(i) if @battle.pbCanSwitchLax?(idxBattler,i)
+    end
+    return -1 if enemies.length==0
+    return pbChooseBestNewEnemy(idxBattler,party,enemies)
+  end
+
+  def pbChooseBestNewEnemy(idxBattler,party,enemies)
+    return -1 if !enemies || enemies.length==0
+    best    = -1
+    bestSum = 0
+    enemies.each do |i|
+      pkmn = party[i]
+      sum  = 0
+      pkmn.moves.each do |m|
+        next if m.base_damage == 0
+        @battle.battlers[idxBattler].eachOpposing do |b|
+          bTypes = b.pbTypes(true)
+          sum += PBTypes.getCombinedEffectiveness(m.type, bTypes[0], bTypes[1], bTypes[2])
+        end
+      end
+      if best==-1 || sum>bestSum
+        best = i
+        bestSum = sum
+      end
+    end
+    return best
+  end
+end