Document day_care.inc and related

2 files changed, 146 insertions, 153 deletions

diff --git a/src/daycare.c b/src/daycare.c
index dc44b4887..bd705e73f 100644
--- a/src/daycare.c
+++ b/src/daycare.c
@@ -3,14 +3,11 @@
 #include "battle.h"
 #include "daycare.h"
 #include "string_util.h"
-#include "constants/species.h"
-#include "constants/items.h"
 #include "mail.h"
 #include "pokemon_storage_system.h"
 #include "event_data.h"
 #include "random.h"
 #include "main.h"
-#include "constants/moves.h"
 #include "egg_hatch.h"
 #include "text.h"
 #include "menu.h"
@@ -22,9 +19,10 @@
 #include "party_menu.h"
 #include "list_menu.h"
 #include "overworld.h"
-
-#define EGG_MOVES_ARRAY_COUNT           10
-#define EGG_LVL_UP_MOVES_ARRAY_COUNT    50
+#include "constants/items.h"
+#include "constants/moves.h"
+#include "constants/region_map_sections.h"
+#include "constants/species.h"
 
 // this file's functions
 static void ClearDaycareMonMail(struct DayCareMail *mail);
@@ -52,11 +50,13 @@ static const struct WindowTemplate sDaycareLevelMenuWindowTemplate =
     .baseBlock = 8
 };
 
+// Indices here are assigned by Task_HandleDaycareLevelMenuInput to VAR_RESULT,
+// which is copied to VAR_0x8004 and used as an index for GetDaycareCost
 static const struct ListMenuItem sLevelMenuItems[] =
 {
-    {gExpandedPlaceholder_Empty, 0},
-    {gExpandedPlaceholder_Empty, 1},
-    {gText_Exit, 5}
+    {gExpandedPlaceholder_Empty, EGG_MOTHER},
+    {gExpandedPlaceholder_Empty, EGG_FATHER},
+    {gText_Exit, DAYCARE_LEVEL_MENU_EXIT}
 };
 
 static const struct ListMenuTemplate sDaycareListMenuLevelTemplate =
@@ -202,16 +202,16 @@ void StoreSelectedPokemonInDaycare(void)
 static void ShiftDaycareSlots(struct DayCare *daycare)
 {
     // This condition is only satisfied when the player takes out the first pokemon from the daycare.
-    if (GetBoxMonData(&daycare->mons[1].mon, MON_DATA_SPECIES) != 0
-        && GetBoxMonData(&daycare->mons[0].mon, MON_DATA_SPECIES) == 0)
+    if (GetBoxMonData(&daycare->mons[EGG_FATHER].mon, MON_DATA_SPECIES) != SPECIES_NONE
+        && GetBoxMonData(&daycare->mons[EGG_MOTHER].mon, MON_DATA_SPECIES) == SPECIES_NONE)
     {
-        daycare->mons[0].mon = daycare->mons[1].mon;
-        ZeroBoxMonData(&daycare->mons[1].mon);
+        daycare->mons[EGG_MOTHER].mon = daycare->mons[EGG_FATHER].mon;
+        ZeroBoxMonData(&daycare->mons[EGG_FATHER].mon);
 
-        daycare->mons[0].mail = daycare->mons[1].mail;
-        daycare->mons[0].steps = daycare->mons[1].steps;
-        daycare->mons[1].steps = 0;
-        ClearDaycareMonMail(&daycare->mons[1].mail);
+        daycare->mons[EGG_MOTHER].mail = daycare->mons[EGG_FATHER].mail;
+        daycare->mons[EGG_MOTHER].steps = daycare->mons[EGG_FATHER].steps;
+        daycare->mons[EGG_FATHER].steps = 0;
+        ClearDaycareMonMail(&daycare->mons[EGG_FATHER].mail);
     }
 }
 
@@ -341,8 +341,8 @@ void GetDaycareCost(void)
 
 static void Debug_AddDaycareSteps(u16 numSteps)
 {
-    gSaveBlock1Ptr->daycare.mons[0].steps += numSteps;
-    gSaveBlock1Ptr->daycare.mons[1].steps += numSteps;
+    gSaveBlock1Ptr->daycare.mons[EGG_MOTHER].steps += numSteps;
+    gSaveBlock1Ptr->daycare.mons[EGG_FATHER].steps += numSteps;
 }
 
 u8 GetNumLevelsGainedFromDaycare(void)
@@ -419,18 +419,18 @@ static u16 GetEggSpecies(u16 species)
     return species;
 }
 
-static s32 GetSlotToInheritNature(struct DayCare *daycare)
+static s32 GetParentToInheritNature(struct DayCare *daycare)
 {
     u32 species[DAYCARE_MON_COUNT];
     s32 i;
     s32 dittoCount;
-    s32 slot = -1;
+    s32 parent = NEITHER_PARENT;
 
     // search for female gender
     for (i = 0; i < DAYCARE_MON_COUNT; i++)
     {
         if (GetBoxMonGender(&daycare->mons[i].mon) == MON_FEMALE)
-            slot = i;
+            parent = i;
     }
 
     // search for ditto
@@ -438,50 +438,52 @@ static s32 GetSlotToInheritNature(struct DayCare *daycare)
     {
         species[i] = GetBoxMonData(&daycare->mons[i].mon, MON_DATA_SPECIES);
         if (species[i] == SPECIES_DITTO)
-            dittoCount++, slot = i;
+            dittoCount++, parent = i;
     }
 
     // coin flip on ...two Dittos
-    if (dittoCount == 2)
+    if (dittoCount == DAYCARE_MON_COUNT)
     {
         if (Random() >= USHRT_MAX / 2)
-            slot = 0;
+            parent = EGG_MOTHER;
         else
-            slot = 1;
+            parent = EGG_FATHER;
     }
 
-    // nature inheritance only if holds everstone
-    if (GetBoxMonData(&daycare->mons[slot].mon, MON_DATA_HELD_ITEM) != ITEM_EVERSTONE
+    // Don't inherit nature if not holding Everstone
+    if (GetBoxMonData(&daycare->mons[parent].mon, MON_DATA_HELD_ITEM) != ITEM_EVERSTONE
         || Random() >= USHRT_MAX / 2)
     {
-        return -1;
+        return NEITHER_PARENT;
     }
 
-    return slot;
+    return parent;
 }
 
 static void _TriggerPendingDaycareEgg(struct DayCare *daycare)
 {
-    s32 natureSlot;
+    s32 parent;
     s32 natureTries = 0;
 
     SeedRng2(gMain.vblankCounter2);
-    natureSlot = GetSlotToInheritNature(daycare);
+    parent = GetParentToInheritNature(daycare);
 
-    if (natureSlot < 0)
+    // don't inherit nature
+    if (parent < 0)
     {
-        daycare->offspringPersonality = (Random2() << 0x10) | ((Random() % 0xfffe) + 1);
+        daycare->offspringPersonality = (Random2() << 16) | ((Random() % 0xfffe) + 1);
     }
+    // inherit nature
     else
     {
-        u8 wantedNature = GetNatureFromPersonality(GetBoxMonData(&daycare->mons[natureSlot].mon, MON_DATA_PERSONALITY, NULL));
+        u8 wantedNature = GetNatureFromPersonality(GetBoxMonData(&daycare->mons[parent].mon, MON_DATA_PERSONALITY, NULL));
         u32 personality;
 
         do
         {
-            personality = (Random2() << 0x10) | (Random());
+            personality = (Random2() << 16) | (Random());
             if (wantedNature == GetNatureFromPersonality(personality) && personality != 0)
-                break; // we found a personality with the same nature
+                break; // found a personality with the same nature
 
             natureTries++;
         } while (natureTries <= 2400);
@@ -492,9 +494,10 @@ static void _TriggerPendingDaycareEgg(struct DayCare *daycare)
     FlagSet(FLAG_PENDING_DAYCARE_EGG);
 }
 
+// Functionally unused
 static void _TriggerPendingDaycareMaleEgg(struct DayCare *daycare)
 {
-    daycare->offspringPersonality = (Random()) | (0x8000);
+    daycare->offspringPersonality = (Random()) | (EGG_GENDER_MALE);
     FlagSet(FLAG_PENDING_DAYCARE_EGG);
 }
 
@@ -503,6 +506,7 @@ void TriggerPendingDaycareEgg(void)
     _TriggerPendingDaycareEgg(&gSaveBlock1Ptr->daycare);
 }
 
+// Unused
 static void TriggerPendingDaycareMaleEgg(void)
 {
     _TriggerPendingDaycareMaleEgg(&gSaveBlock1Ptr->daycare);
@@ -532,9 +536,9 @@ static void RemoveIVIndexFromList(u8 *ivs, u8 selectedIv)
 static void InheritIVs(struct Pokemon *egg, struct DayCare *daycare)
 {
     u8 i;
-    u8 selectedIvs[3];
+    u8 selectedIvs[INHERITED_IV_COUNT];
     u8 availableIVs[NUM_STATS];
-    u8 whichParent[ARRAY_COUNT(selectedIvs)];
+    u8 whichParent[INHERITED_IV_COUNT];
     u8 iv;
 
     // Initialize a list of IV indices.
@@ -544,23 +548,21 @@ static void InheritIVs(struct Pokemon *egg, struct DayCare *daycare)
     }
 
     // Select the 3 IVs that will be inherited.
-    for (i = 0; i < ARRAY_COUNT(selectedIvs); i++)
+    for (i = 0; i < INHERITED_IV_COUNT; i++)
     {
-        // Randomly pick an IV from the available list.
+        // Randomly pick an IV from the available list and stop from being chosen again.
         selectedIvs[i] = availableIVs[Random() % (NUM_STATS - i)];
-
-        // Remove the selected IV index from the available IV indices.
         RemoveIVIndexFromList(availableIVs, i);
     }
 
     // Determine which parent each of the selected IVs should inherit from.
-    for (i = 0; i < ARRAY_COUNT(selectedIvs); i++)
+    for (i = 0; i < INHERITED_IV_COUNT; i++)
     {
-        whichParent[i] = Random() % 2;
+        whichParent[i] = Random() % DAYCARE_MON_COUNT;
     }
 
     // Set each of inherited IVs on the egg mon.
-    for (i = 0; i < ARRAY_COUNT(selectedIvs); i++)
+    for (i = 0; i < INHERITED_IV_COUNT; i++)
     {
         switch (selectedIvs[i])
         {
@@ -638,14 +640,14 @@ static void BuildEggMoveset(struct Pokemon *egg, struct BoxPokemon *father, stru
     numSharedParentMoves = 0;
     for (i = 0; i < MAX_MON_MOVES; i++)
     {
-        sHatchedEggMotherMoves[i] = 0;
-        sHatchedEggFatherMoves[i] = 0;
-        sHatchedEggFinalMoves[i] = 0;
+        sHatchedEggMotherMoves[i] = MOVE_NONE;
+        sHatchedEggFatherMoves[i] = MOVE_NONE;
+        sHatchedEggFinalMoves[i] = MOVE_NONE;
     }
     for (i = 0; i < EGG_MOVES_ARRAY_COUNT; i++)
-        sHatchedEggEggMoves[i] = 0;
+        sHatchedEggEggMoves[i] = MOVE_NONE;
     for (i = 0; i < EGG_LVL_UP_MOVES_ARRAY_COUNT; i++)
-        sHatchedEggLevelUpMoves[i] = 0;
+        sHatchedEggLevelUpMoves[i] = MOVE_NONE;
 
     numLevelUpMoves = GetLevelUpMovesBySpecies(GetMonData(egg, MON_DATA_SPECIES), sHatchedEggLevelUpMoves);
     for (i = 0; i < MAX_MON_MOVES; i++)
@@ -732,8 +734,8 @@ static void AlterEggSpeciesWithIncenseItem(u16 *species, struct DayCare *daycare
     u16 motherItem, fatherItem;
     if (*species == SPECIES_WYNAUT || *species == SPECIES_AZURILL)
     {
-        motherItem = GetBoxMonData(&daycare->mons[0].mon, MON_DATA_HELD_ITEM);
-        fatherItem = GetBoxMonData(&daycare->mons[1].mon, MON_DATA_HELD_ITEM);
+        motherItem = GetBoxMonData(&daycare->mons[EGG_MOTHER].mon, MON_DATA_HELD_ITEM);
+        fatherItem = GetBoxMonData(&daycare->mons[EGG_FATHER].mon, MON_DATA_HELD_ITEM);
         if (*species == SPECIES_WYNAUT && motherItem != ITEM_LAX_INCENSE && fatherItem != ITEM_LAX_INCENSE)
         {
             *species = SPECIES_WOBBUFFET;
@@ -748,8 +750,8 @@ static void AlterEggSpeciesWithIncenseItem(u16 *species, struct DayCare *daycare
 
 static void GiveVoltTackleIfLightBall(struct Pokemon *mon, struct DayCare *daycare)
 {
-    u32 motherItem = GetBoxMonData(&daycare->mons[0].mon, MON_DATA_HELD_ITEM);
-    u32 fatherItem = GetBoxMonData(&daycare->mons[1].mon, MON_DATA_HELD_ITEM);
+    u32 motherItem = GetBoxMonData(&daycare->mons[EGG_MOTHER].mon, MON_DATA_HELD_ITEM);
+    u32 fatherItem = GetBoxMonData(&daycare->mons[EGG_FATHER].mon, MON_DATA_HELD_ITEM);
 
     if (motherItem == ITEM_LIGHT_BALL || fatherItem == ITEM_LIGHT_BALL)
     {
@@ -761,60 +763,57 @@ static void GiveVoltTackleIfLightBall(struct Pokemon *mon, struct DayCare *dayca
 static u16 DetermineEggSpeciesAndParentSlots(struct DayCare *daycare, u8 *parentSlots)
 {
     u16 i;
-    u16 species[2];
+    u16 species[DAYCARE_MON_COUNT];
     u16 eggSpecies;
 
-    // Determine which of the daycare mons is the mother and father of the egg.
-    // The 0th index of the parentSlots array is considered the mother slot, and the
-    // 1st index is the father slot.
-    for (i = 0; i < 2; i++)
+    for (i = 0; i < DAYCARE_MON_COUNT; i++)
     {
         species[i] = GetBoxMonData(&daycare->mons[i].mon, MON_DATA_SPECIES);
         if (species[i] == SPECIES_DITTO)
         {
-            parentSlots[0] = i ^ 1;
-            parentSlots[1] = i;
+            parentSlots[EGG_MOTHER] = i ^ 1;
+            parentSlots[EGG_FATHER] = i;
         }
         else if (GetBoxMonGender(&daycare->mons[i].mon) == MON_FEMALE)
         {
-            parentSlots[0] = i;
-            parentSlots[1] = i ^ 1;
+            parentSlots[EGG_MOTHER] = i;
+            parentSlots[EGG_FATHER] = i ^ 1;
         }
     }
 
-    eggSpecies = GetEggSpecies(species[parentSlots[0]]);
-    if (eggSpecies == SPECIES_NIDORAN_F && daycare->offspringPersonality & 0x8000)
+    eggSpecies = GetEggSpecies(species[parentSlots[EGG_MOTHER]]);
+    if (eggSpecies == SPECIES_NIDORAN_F && daycare->offspringPersonality & EGG_GENDER_MALE)
     {
         eggSpecies = SPECIES_NIDORAN_M;
     }
-    if (eggSpecies == SPECIES_ILLUMISE && daycare->offspringPersonality & 0x8000)
+    if (eggSpecies == SPECIES_ILLUMISE && daycare->offspringPersonality & EGG_GENDER_MALE)
     {
         eggSpecies = SPECIES_VOLBEAT;
     }
 
     // Make Ditto the "mother" slot if the other daycare mon is male.
-    if (species[parentSlots[1]] == SPECIES_DITTO && GetBoxMonGender(&daycare->mons[parentSlots[0]].mon) != MON_FEMALE)
+    if (species[parentSlots[EGG_FATHER]] == SPECIES_DITTO && GetBoxMonGender(&daycare->mons[parentSlots[EGG_MOTHER]].mon) != MON_FEMALE)
     {
-        u8 temp = parentSlots[1];
-        parentSlots[1] = parentSlots[0];
-        parentSlots[0] = temp;
+        u8 ditto = parentSlots[EGG_FATHER];
+        parentSlots[EGG_FATHER] = parentSlots[EGG_MOTHER];
+        parentSlots[EGG_MOTHER] = ditto;
     }
 
     return eggSpecies;
 }
 
-static void _GiveEggFromDaycare(struct DayCare *daycare) // give_egg
+static void _GiveEggFromDaycare(struct DayCare *daycare)
 {
     struct Pokemon egg;
     u16 species;
-    u8 parentSlots[2]; // 0th index is "mother" daycare slot, 1st is "father"
+    u8 parentSlots[DAYCARE_MON_COUNT];
     bool8 isEgg;
 
     species = DetermineEggSpeciesAndParentSlots(daycare, parentSlots);
     AlterEggSpeciesWithIncenseItem(&species, daycare);
     SetInitialEggData(&egg, species, daycare);
     InheritIVs(&egg, daycare);
-    BuildEggMoveset(&egg, &daycare->mons[parentSlots[1]].mon, &daycare->mons[parentSlots[0]].mon);
+    BuildEggMoveset(&egg, &daycare->mons[parentSlots[EGG_FATHER]].mon, &daycare->mons[parentSlots[EGG_MOTHER]].mon);
 
     if (species == SPECIES_PICHU)
         GiveVoltTackleIfLightBall(&egg, daycare);
@@ -835,7 +834,7 @@ void CreateEgg(struct Pokemon *mon, u16 species, bool8 setHotSpringsLocation)
     u8 metLocation;
     u8 isEgg;
 
-    CreateMon(mon, species, EGG_HATCH_LEVEL, 0x20, FALSE, 0, OT_ID_PLAYER_ID, 0);
+    CreateMon(mon, species, EGG_HATCH_LEVEL, 32, FALSE, 0, OT_ID_PLAYER_ID, 0);
     metLevel = 0;
     ball = ITEM_POKE_BALL;
     language = LANGUAGE_JAPANESE;
@@ -846,7 +845,7 @@ void CreateEgg(struct Pokemon *mon, u16 species, bool8 setHotSpringsLocation)
     SetMonData(mon, MON_DATA_LANGUAGE, &language);
     if (setHotSpringsLocation)
     {
-        metLocation = 253; // hot springs; see PokemonSummaryScreen_PrintEggTrainerMemo
+        metLocation = METLOC_SPECIAL_EGG;
         SetMonData(mon, MON_DATA_MET_LOCATION, &metLocation);
     }
 
@@ -862,7 +861,7 @@ static void SetInitialEggData(struct Pokemon *mon, u16 species, struct DayCare *
     u8 language;
 
     personality = daycare->offspringPersonality;
-    CreateMon(mon, species, EGG_HATCH_LEVEL, 0x20, TRUE, personality, OT_ID_PLAYER_ID, 0);
+    CreateMon(mon, species, EGG_HATCH_LEVEL, 32, TRUE, personality, OT_ID_PLAYER_ID, 0);
     metLevel = 0;
     ball = ITEM_POKE_BALL;
     language = LANGUAGE_JAPANESE;
@@ -889,7 +888,7 @@ static bool8 _DoEggActions_CheckHatch(struct DayCare *daycare)
     }
 
     // try to trigger poke sex
-    if (daycare->offspringPersonality == 0 && validEggs == 2 && (daycare->mons[1].steps & 0xFF) == 0xFF)
+    if (daycare->offspringPersonality == 0 && validEggs == DAYCARE_MON_COUNT && (daycare->mons[EGG_FATHER].steps & 0xFF) == 0xFF)
     {
         u8 loveScore = GetDaycareCompatibilityScore(daycare);
         if (loveScore > (Random() * 100u) / USHRT_MAX)
@@ -945,16 +944,16 @@ static bool8 IsEggPending(struct DayCare *daycare)
 static void _GetDaycareMonNicknames(struct DayCare *daycare)
 {
     u8 text[12];
-    if (GetBoxMonData(&daycare->mons[0].mon, MON_DATA_SPECIES) != 0)
+    if (GetBoxMonData(&daycare->mons[EGG_MOTHER].mon, MON_DATA_SPECIES) != 0)
     {
-        GetBoxMonNick(&daycare->mons[0].mon, gStringVar1);
-        GetBoxMonData(&daycare->mons[0].mon, MON_DATA_OT_NAME, text);
+        GetBoxMonNick(&daycare->mons[EGG_MOTHER].mon, gStringVar1);
+        GetBoxMonData(&daycare->mons[EGG_MOTHER].mon, MON_DATA_OT_NAME, text);
         StringCopy(gStringVar3, text);
     }
 
-    if (GetBoxMonData(&daycare->mons[1].mon, MON_DATA_SPECIES) != 0)
+    if (GetBoxMonData(&daycare->mons[EGG_FATHER].mon, MON_DATA_SPECIES) != 0)
     {
-        GetBoxMonNick(&daycare->mons[1].mon, gStringVar2);
+        GetBoxMonNick(&daycare->mons[EGG_FATHER].mon, gStringVar2);
     }
 }
 
@@ -971,26 +970,19 @@ void GetDaycareMonNicknames(void)
 
 u8 GetDaycareState(void)
 {
-    // The daycare can be in 4 possible states:
-    //   0: default state--no deposited mons, no egg
-    //   1: there is an egg waiting for the player to pick it up
-    //   2: there is a single pokemon in the daycare
-    //   3: there are two pokemon in the daycare, no egg
-
     u8 numMons;
     if (IsEggPending(&gSaveBlock1Ptr->daycare))
     {
-        // There is an Egg waiting for the player.
-        return 1;
+        return DAYCARE_EGG_WAITING;
     }
 
     numMons = CountPokemonInDaycare(&gSaveBlock1Ptr->daycare);
     if (numMons != 0)
     {
-        return numMons + 1;
+        return numMons + 1; // DAYCARE_ONE_MON or DAYCARE_TWO_MONS
     }
 
-    return 0;
+    return DAYCARE_NO_MONS;
 }
 
 static u8 GetDaycarePokemonCount(void)
@@ -1002,15 +994,15 @@ static u8 GetDaycarePokemonCount(void)
     return 0;
 }
 
+// Determine if the two given egg group lists contain any of the
+// same egg groups.
 static bool8 EggGroupsOverlap(u16 *eggGroups1, u16 *eggGroups2)
 {
-    // Determine if the two given egg group lists contain any of the
-    // same egg groups.
     s32 i, j;
 
-    for (i = 0; i < 2; i++)
+    for (i = 0; i < EGG_GROUPS_PER_MON; i++)
     {
-        for (j = 0; j < 2; j++)
+        for (j = 0; j < EGG_GROUPS_PER_MON; j++)
         {
             if (eggGroups1[i] == eggGroups2[j])
                 return TRUE;
@@ -1023,12 +1015,12 @@ static bool8 EggGroupsOverlap(u16 *eggGroups1, u16 *eggGroups2)
 static u8 GetDaycareCompatibilityScore(struct DayCare *daycare)
 {
     u32 i;
-    u16 eggGroups[2][2];
-    u16 species[2];
-    u32 trainerIds[2];
-    u32 genders[2];
+    u16 eggGroups[DAYCARE_MON_COUNT][EGG_GROUPS_PER_MON];
+    u16 species[DAYCARE_MON_COUNT];
+    u32 trainerIds[DAYCARE_MON_COUNT];
+    u32 genders[DAYCARE_MON_COUNT];
 
-    for (i = 0; i < 2; i++)
+    for (i = 0; i < DAYCARE_MON_COUNT; i++)
     {
         u32 personality;
 
@@ -1041,42 +1033,43 @@ static u8 GetDaycareCompatibilityScore(struct DayCare *daycare)
     }
 
     // check unbreedable egg group
-    if (eggGroups[0][0] == EGG_GROUP_UNDISCOVERED || eggGroups[1][0] == EGG_GROUP_UNDISCOVERED)
-        return 0;
+    if (eggGroups[EGG_MOTHER][0] == EGG_GROUP_UNDISCOVERED || eggGroups[EGG_FATHER][0] == EGG_GROUP_UNDISCOVERED)
+        return PARENTS_INCOMPATIBLE;
     // two Ditto can't breed
-    if (eggGroups[0][0] == EGG_GROUP_DITTO && eggGroups[1][0] == EGG_GROUP_DITTO)
-        return 0;
+    if (eggGroups[EGG_MOTHER][0] == EGG_GROUP_DITTO && eggGroups[EGG_FATHER][0] == EGG_GROUP_DITTO)
+        return PARENTS_INCOMPATIBLE;
 
-    // now that we checked, one ditto can breed with any other mon
-    if (eggGroups[0][0] == EGG_GROUP_DITTO || eggGroups[1][0] == EGG_GROUP_DITTO)
+    // one parent is Ditto
+    if (eggGroups[EGG_MOTHER][0] == EGG_GROUP_DITTO || eggGroups[EGG_FATHER][0] == EGG_GROUP_DITTO)
     {
-        if (trainerIds[0] == trainerIds[1]) // same trainer
-            return 20;
+        if (trainerIds[EGG_MOTHER] == trainerIds[EGG_FATHER])
+            return PARENTS_LOW_COMPATIBILITY;
 
-        return 50; // different trainers, more chance of poke sex
+        return PARENTS_MED_COMPATABILITY;
     }
+    // neither parent is Ditto
     else
     {
-        if (genders[0] == genders[1]) // no homo
-            return 0;
-        if (genders[0] == MON_GENDERLESS || genders[1] == MON_GENDERLESS)
-            return 0;
-        if (!EggGroupsOverlap(eggGroups[0], eggGroups[1])) // not compatible with each other
-            return 0;
-
-        if (species[0] == species[1]) // same species
+        if (genders[EGG_MOTHER] == genders[EGG_FATHER])
+            return PARENTS_INCOMPATIBLE;
+        if (genders[EGG_MOTHER] == MON_GENDERLESS || genders[EGG_FATHER] == MON_GENDERLESS)
+            return PARENTS_INCOMPATIBLE;
+        if (!EggGroupsOverlap(eggGroups[EGG_MOTHER], eggGroups[EGG_FATHER]))
+            return PARENTS_INCOMPATIBLE;
+
+        if (species[EGG_MOTHER] == species[EGG_FATHER])
         {
-            if (trainerIds[0] == trainerIds[1]) // same species and trainer
-                return 50;
+            if (trainerIds[EGG_MOTHER] == trainerIds[EGG_FATHER])
+                return PARENTS_MED_COMPATABILITY; // same species, same trainer
 
-            return 70; // different trainers, same species
+            return PARENTS_MAX_COMPATABILITY; // same species, different trainers
         }
         else
         {
-            if (trainerIds[0] != trainerIds[1]) // different trainers, different species
-                return 50;
+            if (trainerIds[EGG_MOTHER] != trainerIds[EGG_FATHER])
+                return PARENTS_MED_COMPATABILITY; // different species, different trainers
 
-            return 20; // different species, same trainer
+            return PARENTS_LOW_COMPATIBILITY; // different species, same trainer
         }
     }
 }
@@ -1093,13 +1086,13 @@ void SetDaycareCompatibilityString(void)
 
     relationshipScore = GetDaycareCompatibilityScoreFromSave();
     whichString = 0;
-    if (relationshipScore == 0)
+    if (relationshipScore == PARENTS_INCOMPATIBLE)
         whichString = 3;
-    if (relationshipScore == 20)
+    if (relationshipScore == PARENTS_LOW_COMPATIBILITY)
         whichString = 2;
-    if (relationshipScore == 50)
+    if (relationshipScore == PARENTS_MED_COMPATABILITY)
         whichString = 1;
-    if (relationshipScore == 70)
+    if (relationshipScore == PARENTS_MAX_COMPATABILITY)
         whichString = 0;
 
     StringCopy(gStringVar4, sCompatibilityMessages[whichString]);
@@ -1108,20 +1101,20 @@ void SetDaycareCompatibilityString(void)
 bool8 NameHasGenderSymbol(const u8 *name, u8 genderRatio)
 {
     u8 i;
-    u8 symbolsCount[2]; // male, female
-    symbolsCount[0] = symbolsCount[1] = 0;
+    u8 symbolsCount[GENDER_COUNT];
+    symbolsCount[MALE] = symbolsCount[FEMALE] = 0;
 
     for (i = 0; name[i] != EOS; i++)
     {
         if (name[i] == CHAR_MALE)
-            symbolsCount[0]++;
+            symbolsCount[MALE]++;
         if (name[i] == CHAR_FEMALE)
-            symbolsCount[1]++;
+            symbolsCount[FEMALE]++;
     }
 
-    if (genderRatio == MON_MALE   && symbolsCount[0] != 0 && symbolsCount[1] == 0)
+    if (genderRatio == MON_MALE   && symbolsCount[MALE] != 0 && symbolsCount[FEMALE] == 0)
         return TRUE;
-    if (genderRatio == MON_FEMALE && symbolsCount[1] != 0 && symbolsCount[0] == 0)
+    if (genderRatio == MON_FEMALE && symbolsCount[FEMALE] != 0 && symbolsCount[MALE] == 0)
         return TRUE;
 
     return FALSE;
@@ -1150,19 +1143,19 @@ static u8 *AppendMonGenderSymbol(u8 *name, struct BoxPokemon *boxMon)
 
 static void GetDaycareLevelMenuText(struct DayCare *daycare, u8 *dest)
 {
-    u8 monNames[2][20];
+    u8 monNames[DAYCARE_MON_COUNT][20];
     u8 i;
 
     *dest = EOS;
-    for (i = 0; i < 2; i++)
+    for (i = 0; i < DAYCARE_MON_COUNT; i++)
     {
         GetBoxMonNick(&daycare->mons[i].mon, monNames[i]);
         AppendMonGenderSymbol(monNames[i], &daycare->mons[i].mon);
     }
 
-    StringCopy(dest, monNames[0]);
+    StringCopy(dest, monNames[EGG_MOTHER]);
     StringAppend(dest, gText_NewLine2);
-    StringAppend(dest, monNames[1]);
+    StringAppend(dest, monNames[EGG_FATHER]);
     StringAppend(dest, gText_NewLine2);
     StringAppend(dest, gText_Exit4);
 }
@@ -1174,7 +1167,7 @@ static void GetDaycareLevelMenuLevelText(struct DayCare *daycare, u8 *dest)
     u8 text[20];
 
     *dest = EOS;
-    for (i = 0; i < 2; i++)
+    for (i = 0; i < DAYCARE_MON_COUNT; i++)
     {
         StringAppend(dest, gText_Lv);
         level = GetLevelAfterDaycareSteps(&daycare->mons[i].mon, daycare->mons[i].steps);
@@ -1250,12 +1243,12 @@ static void Task_HandleDaycareLevelMenuInput(u8 taskId)
     {
         switch (input)
         {
-        case 0:
-        case 1:
+        case EGG_MOTHER:
+        case EGG_FATHER:
             gSpecialVar_Result = input;
             break;
-        case 5:
-            gSpecialVar_Result = 2;
+        case DAYCARE_LEVEL_MENU_EXIT:
+            gSpecialVar_Result = DAYCARE_EXITED_LEVEL_MENU;
             break;
         }
         DestroyListMenuTask(gTasks[taskId].tMenuListTaskId, NULL, NULL);
@@ -1266,7 +1259,7 @@ static void Task_HandleDaycareLevelMenuInput(u8 taskId)
     }
     else if (gMain.newKeys & B_BUTTON)
     {
-        gSpecialVar_Result = 2;
+        gSpecialVar_Result = DAYCARE_EXITED_LEVEL_MENU;
         DestroyListMenuTask(gTasks[taskId].tMenuListTaskId, NULL, NULL);
         ClearStdWindowAndFrame(gTasks[taskId].tWindowId, TRUE);
         RemoveWindow(gTasks[taskId].tWindowId);
diff --git a/src/egg_hatch.c b/src/egg_hatch.c
index 4fba8578c..5262c4af4 100644
--- a/src/egg_hatch.c
+++ b/src/egg_hatch.c
@@ -388,13 +388,13 @@ void ScriptHatchMon(void)
     AddHatchedMonToParty(gSpecialVar_0x8004);
 }
 
-static bool8 sub_807158C(struct DayCare *daycare, u8 daycareId)
+static bool8 _CheckDaycareMonReceivedMail(struct DayCare *daycare, u8 daycareId)
 {
-    u8 nick[0x20];
+    u8 nick[32];
     struct DaycareMon *daycareMon = &daycare->mons[daycareId];
 
     GetBoxMonNick(&daycareMon->mon, nick);
-    if (daycareMon->mail.message.itemId != 0
+    if (daycareMon->mail.message.itemId != ITEM_NONE
         && (StringCompareWithoutExtCtrlCodes(nick, daycareMon->mail.monName) != 0
             || StringCompareWithoutExtCtrlCodes(gSaveBlock2Ptr->playerName, daycareMon->mail.OT_name) != 0))
     {
@@ -406,9 +406,9 @@ static bool8 sub_807158C(struct DayCare *daycare, u8 daycareId)
     return FALSE;
 }
 
-bool8 sub_8071614(void)
+bool8 CheckDaycareMonReceivedMail(void)
 {
-    return sub_807158C(&gSaveBlock1Ptr->daycare, gSpecialVar_0x8004);
+    return _CheckDaycareMonReceivedMail(&gSaveBlock1Ptr->daycare, gSpecialVar_0x8004);
 }
 
 static u8 EggHatchCreateMonSprite(u8 a0, u8 switchID, u8 pokeID, u16* speciesLoc)
@@ -880,9 +880,9 @@ u8 GetEggStepsToSubtract(void)
     return 1;
 }
 
-u16 sub_80722E0(void)
+u16 CountPartyAliveNonEggMons(void)
 {
     u16 aliveNonEggMonsCount = CountStorageNonEggMons();
-    aliveNonEggMonsCount += CountPartyAliveNonEggMonsExcept(6);
+    aliveNonEggMonsCount += CountPartyAliveNonEggMonsExcept(PARTY_SIZE);
     return aliveNonEggMonsCount;
 }