Merge remote-tracking branch 'Egg/decompile_mail_data'

22 files changed, 416 insertions, 799 deletions

diff --git a/asm/international_string_util.s b/asm/international_string_util.s
index 08e435249..469d88787 100755
--- a/asm/international_string_util.s
+++ b/asm/international_string_util.s
@@ -113,8 +113,8 @@ _081DB4D4:
 	bx r1
 	thumb_func_end sub_81DB494
 
-	thumb_func_start sub_81DB4DC
-sub_81DB4DC: @ 81DB4DC
+	thumb_func_start PadNameString
+PadNameString: @ 81DB4DC
 	push {r4,r5,lr}
 	adds r4, r0, 0
 	lsls r1, 24
@@ -156,7 +156,7 @@ _081DB51E:
 	pop {r4,r5}
 	pop {r0}
 	bx r0
-	thumb_func_end sub_81DB4DC
+	thumb_func_end PadNameString
 
 	thumb_func_start sub_81DB52C
 sub_81DB52C: @ 81DB52C
diff --git a/asm/item_menu.s b/asm/item_menu.s
index 9c9916e37..1be72593a 100755
--- a/asm/item_menu.s
+++ b/asm/item_menu.s
@@ -3360,7 +3360,7 @@ _081AC8D4:
 	bl memcpy
 	ldr r0, =gSpecialVar_ItemId
 	ldrh r0, [r0]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0x1
@@ -4664,7 +4664,7 @@ item_menu_type_b: @ 81AD4B4
 	lsrs r4, r0, 24
 	ldr r5, =gSpecialVar_ItemId
 	ldrh r0, [r5]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0x1
diff --git a/asm/item_use.s b/asm/item_use.s
index 172080b16..f732c34e9 100644
--- a/asm/item_use.s
+++ b/asm/item_use.s
@@ -266,7 +266,7 @@ sub_80FD254: @ 80FD254
 	ldr r1, =bag_menu_mail_related
 	mov r0, sp
 	movs r2, 0
-	bl sub_8121478
+	bl ReadMail
 	add sp, 0x24
 	pop {r0}
 	bx r0
diff --git a/asm/mail_data.s b/asm/mail_data.s
deleted file mode 100755
index 70fc856d1..000000000
--- a/asm/mail_data.s
+++ /dev/null
@@ -1,589 +0,0 @@
-	.include "asm/macros.inc"
-	.include "constants/constants.inc"
-
-	.syntax unified
-
-	.text
-
-	thumb_func_start ClearMailData
-ClearMailData: @ 80D436C
-	push {r4,r5,lr}
-	movs r4, 0
-	ldr r5, =gSaveBlock1Ptr
-_080D4372:
-	lsls r1, r4, 3
-	adds r1, r4
-	lsls r1, 2
-	ldr r0, =0x00002be0
-	adds r1, r0
-	ldr r0, [r5]
-	adds r0, r1
-	bl ClearMailStruct
-	adds r0, r4, 0x1
-	lsls r0, 24
-	lsrs r4, r0, 24
-	cmp r4, 0xF
-	bls _080D4372
-	pop {r4,r5}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end ClearMailData
-
-	thumb_func_start ClearMailStruct
-ClearMailStruct: @ 80D439C
-	push {r4-r6,lr}
-	adds r3, r0, 0
-	ldr r0, =0x0000ffff
-	adds r4, r0, 0
-	adds r1, r3, 0
-	movs r2, 0x8
-_080D43A8:
-	ldrh r0, [r1]
-	orrs r0, r4
-	strh r0, [r1]
-	adds r1, 0x2
-	subs r2, 0x1
-	cmp r2, 0
-	bge _080D43A8
-	movs r2, 0
-	adds r6, r3, 0
-	adds r6, 0x1A
-	adds r4, r3, 0
-	adds r4, 0x12
-	movs r5, 0xFF
-_080D43C2:
-	adds r1, r4, r2
-	ldrb r0, [r1]
-	orrs r0, r5
-	strb r0, [r1]
-	adds r2, 0x1
-	cmp r2, 0x7
-	ble _080D43C2
-	adds r1, r6, 0
-	movs r2, 0
-	adds r0, r1, 0x3
-_080D43D6:
-	strb r2, [r0]
-	subs r0, 0x1
-	cmp r0, r1
-	bge _080D43D6
-	movs r1, 0
-	movs r0, 0x1
-	strh r0, [r3, 0x1E]
-	strh r1, [r3, 0x20]
-	pop {r4-r6}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end ClearMailStruct
-
-	thumb_func_start MonHasMail
-MonHasMail: @ 80D43F0
-	push {r4,lr}
-	adds r4, r0, 0
-	movs r1, 0xC
-	bl GetMonData
-	lsls r0, 16
-	lsrs r0, 16
-	bl itemid_is_mail
-	lsls r0, 24
-	cmp r0, 0
-	beq _080D4418
-	adds r0, r4, 0
-	movs r1, 0x40
-	bl GetMonData
-	cmp r0, 0xFF
-	beq _080D4418
-	movs r0, 0x1
-	b _080D441A
-_080D4418:
-	movs r0, 0
-_080D441A:
-	pop {r4}
-	pop {r1}
-	bx r1
-	thumb_func_end MonHasMail
-
-	thumb_func_start sub_80D4420
-sub_80D4420: @ 80D4420
-	push {r4-r7,lr}
-	mov r7, r10
-	mov r6, r9
-	mov r5, r8
-	push {r5-r7}
-	sub sp, 0xC
-	mov r8, r0
-	lsls r1, 16
-	lsrs r0, r1, 16
-	str r0, [sp, 0x8]
-	mov r0, sp
-	movs r2, 0
-	ldrb r3, [r0, 0x8]
-	strb r3, [r0]
-	lsrs r1, 24
-	strb r1, [r0, 0x1]
-	add r3, sp, 0x4
-	strb r2, [r3]
-	ldr r4, =gSaveBlock1Ptr
-	mov r10, r4
-	mov r9, r3
-	adds r4, r3, 0
-_080D444C:
-	mov r1, r10
-	ldr r0, [r1]
-	ldrb r2, [r4]
-	lsls r1, r2, 3
-	adds r1, r2
-	lsls r1, 2
-	adds r0, r1
-	movs r1, 0xB0
-	lsls r1, 6
-	adds r0, r1
-	ldrh r0, [r0]
-	cmp r0, 0
-	beq _080D4468
-	b _080D45A8
-_080D4468:
-	movs r4, 0
-	ldr r2, =gSaveBlock2Ptr
-	mov r12, r2
-	ldr r7, =gSaveBlock1Ptr
-	add r5, sp, 0x4
-	ldr r3, =0x0000ffff
-	adds r6, r3, 0
-_080D4476:
-	ldr r2, [r7]
-	lsls r3, r4, 1
-	ldrb r1, [r5]
-	lsls r0, r1, 3
-	adds r0, r1
-	lsls r0, 2
-	adds r3, r0
-	ldr r0, =0x00002be0
-	adds r2, r0
-	adds r2, r3
-	ldrh r0, [r2]
-	orrs r0, r6
-	strh r0, [r2]
-	adds r0, r4, 0x1
-	lsls r0, 24
-	lsrs r4, r0, 24
-	cmp r4, 0x8
-	bls _080D4476
-	movs r4, 0
-	ldr r5, =gSaveBlock1Ptr
-	add r3, sp, 0x4
-_080D44A0:
-	ldr r2, [r5]
-	ldrb r1, [r3]
-	lsls r0, r1, 3
-	adds r0, r1
-	lsls r0, 2
-	adds r0, r4, r0
-	ldr r1, =0x00002bf2
-	adds r2, r1
-	adds r2, r0
-	mov r1, r12
-	ldr r0, [r1]
-	adds r0, r4
-	ldrb r0, [r0]
-	strb r0, [r2]
-	adds r0, r4, 0x1
-	lsls r0, 24
-	lsrs r4, r0, 24
-	cmp r4, 0x6
-	bls _080D44A0
-	mov r3, r10
-	ldr r2, [r3]
-	mov r0, r9
-	ldrb r1, [r0]
-	lsls r0, r1, 3
-	adds r0, r1
-	lsls r0, 2
-	adds r0, r4, r0
-	ldr r1, =0x00002bf2
-	adds r2, r1
-	adds r2, r0
-	movs r0, 0xFF
-	strb r0, [r2]
-	mov r2, r9
-	ldrb r1, [r2]
-	lsls r0, r1, 3
-	adds r0, r1
-	lsls r0, 2
-	ldr r1, [r3]
-	adds r0, r1
-	ldr r3, =0x00002bf2
-	adds r0, r3
-	movs r1, 0
-	bl sub_81DB4DC
-	movs r4, 0
-	ldr r6, =gSaveBlock1Ptr
-	add r3, sp, 0x4
-	ldr r5, =gSaveBlock2Ptr
-_080D4500:
-	ldr r2, [r6]
-	ldrb r1, [r3]
-	lsls r0, r1, 3
-	adds r0, r1
-	lsls r0, 2
-	adds r0, r4, r0
-	ldr r1, =0x00002bfa
-	adds r2, r1
-	adds r2, r0
-	ldr r0, [r5]
-	adds r0, 0xA
-	adds r0, r4
-	ldrb r0, [r0]
-	strb r0, [r2]
-	adds r0, r4, 0x1
-	lsls r0, 24
-	lsrs r4, r0, 24
-	cmp r4, 0x3
-	bls _080D4500
-	mov r0, r8
-	movs r1, 0xB
-	bl GetBoxMonData
-	adds r4, r0, 0
-	lsls r4, 16
-	lsrs r4, 16
-	mov r0, r8
-	movs r1, 0
-	bl GetBoxMonData
-	adds r1, r0, 0
-	adds r0, r4, 0
-	bl sub_80D45C8
-	mov r2, r10
-	ldr r3, [r2]
-	mov r4, r9
-	ldrb r2, [r4]
-	lsls r1, r2, 3
-	adds r1, r2
-	lsls r1, 2
-	adds r1, r3, r1
-	ldr r2, =0x00002bfe
-	adds r1, r2
-	strh r0, [r1]
-	ldrb r1, [r4]
-	lsls r0, r1, 3
-	adds r0, r1
-	lsls r0, 2
-	adds r3, r0
-	movs r4, 0xB0
-	lsls r4, 6
-	adds r3, r4
-	mov r0, sp
-	ldrh r0, [r0, 0x8]
-	strh r0, [r3]
-	mov r0, r8
-	movs r1, 0x40
-	mov r2, r9
-	bl SetMonData
-	mov r0, r8
-	movs r1, 0xC
-	mov r2, sp
-	bl SetMonData
-	mov r1, r9
-	ldrb r0, [r1]
-	b _080D45B6
-	.pool
-_080D45A8:
-	adds r0, r2, 0x1
-	strb r0, [r3]
-	ldrb r0, [r4]
-	cmp r0, 0x5
-	bhi _080D45B4
-	b _080D444C
-_080D45B4:
-	movs r0, 0xFF
-_080D45B6:
-	add sp, 0xC
-	pop {r3-r5}
-	mov r8, r3
-	mov r9, r4
-	mov r10, r5
-	pop {r4-r7}
-	pop {r1}
-	bx r1
-	thumb_func_end sub_80D4420
-
-	thumb_func_start sub_80D45C8
-sub_80D45C8: @ 80D45C8
-	push {lr}
-	lsls r0, 16
-	lsrs r0, 16
-	cmp r0, 0xC9
-	bne _080D45E0
-	adds r0, r1, 0
-	bl mon_icon_personality_to_unown_id
-	lsls r0, 16
-	ldr r1, =0x75300000
-	adds r0, r1
-	lsrs r0, 16
-_080D45E0:
-	pop {r1}
-	bx r1
-	.pool
-	thumb_func_end sub_80D45C8
-
-	thumb_func_start sub_80D45E8
-sub_80D45E8: @ 80D45E8
-	push {lr}
-	lsls r0, 16
-	lsrs r3, r0, 16
-	ldr r0, =0xffff8ad0
-	adds r2, r3, r0
-	lsls r0, r2, 16
-	lsrs r0, 16
-	cmp r0, 0x1B
-	bhi _080D4604
-	movs r0, 0xC9
-	strh r2, [r1]
-	b _080D4606
-	.pool
-_080D4604:
-	adds r0, r3, 0
-_080D4606:
-	pop {r1}
-	bx r1
-	thumb_func_end sub_80D45E8
-
-	thumb_func_start GiveMailToMon2
-GiveMailToMon2: @ 80D460C
-	push {r4-r7,lr}
-	sub sp, 0x8
-	adds r6, r0, 0
-	adds r7, r1, 0
-	ldrh r5, [r7, 0x20]
-	adds r1, r5, 0
-	bl sub_80D4420
-	add r4, sp, 0x4
-	strb r0, [r4]
-	ldrb r2, [r4]
-	cmp r2, 0xFF
-	beq _080D4670
-	ldr r0, =gSaveBlock1Ptr
-	ldr r1, [r0]
-	lsls r0, r2, 3
-	adds r0, r2
-	lsls r0, 2
-	adds r1, r0
-	ldr r0, =0x00002be0
-	adds r1, r0
-	adds r0, r7, 0
-	ldm r0!, {r2,r3,r7}
-	stm r1!, {r2,r3,r7}
-	ldm r0!, {r2,r3,r7}
-	stm r1!, {r2,r3,r7}
-	ldm r0!, {r2,r3,r7}
-	stm r1!, {r2,r3,r7}
-	adds r0, r6, 0
-	movs r1, 0x40
-	adds r2, r4, 0
-	bl SetMonData
-	mov r0, sp
-	strb r5, [r0]
-	mov r1, sp
-	lsrs r0, r5, 8
-	strb r0, [r1, 0x1]
-	adds r0, r6, 0
-	movs r1, 0xC
-	mov r2, sp
-	bl SetMonData
-	ldrb r0, [r4]
-	b _080D4672
-	.pool
-_080D4670:
-	movs r0, 0xFF
-_080D4672:
-	add sp, 0x8
-	pop {r4-r7}
-	pop {r1}
-	bx r1
-	thumb_func_end GiveMailToMon2
-
-	thumb_func_start sub_80D467C
-sub_80D467C: @ 80D467C
-	movs r0, 0
-	bx lr
-	thumb_func_end sub_80D467C
-
-	thumb_func_start TakeMailFromMon
-TakeMailFromMon: @ 80D4680
-	push {r4,lr}
-	sub sp, 0x8
-	adds r4, r0, 0
-	bl MonHasMail
-	lsls r0, 24
-	cmp r0, 0
-	beq _080D46D2
-	adds r0, r4, 0
-	movs r1, 0x40
-	bl GetMonData
-	add r2, sp, 0x4
-	strb r0, [r2]
-	ldr r0, =gSaveBlock1Ptr
-	ldr r3, [r0]
-	ldrb r1, [r2]
-	lsls r0, r1, 3
-	adds r0, r1
-	lsls r0, 2
-	adds r3, r0
-	movs r0, 0xB0
-	lsls r0, 6
-	adds r3, r0
-	movs r1, 0
-	movs r0, 0
-	strh r0, [r3]
-	movs r0, 0xFF
-	strb r0, [r2]
-	mov r0, sp
-	strb r1, [r0]
-	strb r1, [r0, 0x1]
-	adds r0, r4, 0
-	movs r1, 0x40
-	bl SetMonData
-	adds r0, r4, 0
-	movs r1, 0xC
-	mov r2, sp
-	bl SetMonData
-_080D46D2:
-	add sp, 0x8
-	pop {r4}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end TakeMailFromMon
-
-	thumb_func_start sub_80D46E0
-sub_80D46E0: @ 80D46E0
-	lsls r0, 24
-	lsrs r0, 24
-	ldr r1, =gSaveBlock1Ptr
-	ldr r2, [r1]
-	lsls r1, r0, 3
-	adds r1, r0
-	lsls r1, 2
-	adds r2, r1
-	movs r0, 0xB0
-	lsls r0, 6
-	adds r2, r0
-	movs r0, 0
-	strh r0, [r2]
-	bx lr
-	.pool
-	thumb_func_end sub_80D46E0
-
-	thumb_func_start sub_80D4700
-sub_80D4700: @ 80D4700
-	push {r4-r7,lr}
-	mov r7, r9
-	mov r6, r8
-	push {r6,r7}
-	sub sp, 0xC
-	adds r5, r0, 0
-	mov r0, sp
-	movs r1, 0
-	strb r1, [r0]
-	strb r1, [r0, 0x1]
-	add r1, sp, 0x4
-	movs r0, 0xFF
-	strb r0, [r1]
-	movs r7, 0x6
-	mov r9, r1
-	ldr r0, =gSaveBlock1Ptr
-	mov r8, r0
-	ldr r3, =0x00002be0
-_080D4724:
-	mov r1, r8
-	ldr r0, [r1]
-	lsls r1, r7, 3
-	adds r1, r7
-	lsls r1, 2
-	adds r4, r0, r1
-	movs r2, 0xB0
-	lsls r2, 6
-	adds r0, r4, r2
-	ldrh r6, [r0]
-	cmp r6, 0
-	bne _080D47A0
-	adds r4, r3
-	adds r0, r5, 0
-	movs r1, 0x40
-	str r3, [sp, 0x8]
-	bl GetMonData
-	mov r1, r8
-	ldr r2, [r1]
-	lsls r1, r0, 3
-	adds r1, r0
-	lsls r1, 2
-	adds r1, r2
-	ldr r3, [sp, 0x8]
-	adds r1, r3
-	ldm r1!, {r0,r2,r3}
-	stm r4!, {r0,r2,r3}
-	ldm r1!, {r0,r2,r3}
-	stm r4!, {r0,r2,r3}
-	ldm r1!, {r0,r2,r3}
-	stm r4!, {r0,r2,r3}
-	adds r0, r5, 0
-	movs r1, 0x40
-	bl GetMonData
-	mov r1, r8
-	ldr r2, [r1]
-	lsls r1, r0, 3
-	adds r1, r0
-	lsls r1, 2
-	adds r2, r1
-	movs r3, 0xB0
-	lsls r3, 6
-	adds r2, r3
-	strh r6, [r2]
-	adds r0, r5, 0
-	movs r1, 0x40
-	mov r2, r9
-	bl SetMonData
-	adds r0, r5, 0
-	movs r1, 0xC
-	mov r2, sp
-	bl SetMonData
-	adds r0, r7, 0
-	b _080D47AC
-	.pool
-_080D47A0:
-	adds r0, r7, 0x1
-	lsls r0, 24
-	lsrs r7, r0, 24
-	cmp r7, 0xF
-	bls _080D4724
-	movs r0, 0xFF
-_080D47AC:
-	add sp, 0xC
-	pop {r3,r4}
-	mov r8, r3
-	mov r9, r4
-	pop {r4-r7}
-	pop {r1}
-	bx r1
-	thumb_func_end sub_80D4700
-
-	thumb_func_start itemid_is_mail
-itemid_is_mail: @ 80D47BC
-	push {lr}
-	lsls r0, 16
-	lsrs r0, 16
-	cmp r0, 0x84
-	bgt _080D47CE
-	cmp r0, 0x79
-	blt _080D47CE
-	movs r0, 0x1
-	b _080D47D0
-_080D47CE:
-	movs r0, 0
-_080D47D0:
-	pop {r1}
-	bx r1
-	thumb_func_end itemid_is_mail
-
-	.align 2, 0 @ Don't pad with nop.
diff --git a/asm/menu_helpers.s b/asm/menu_helpers.s
index 444632dc5..7419bd56f 100644
--- a/asm/menu_helpers.s
+++ b/asm/menu_helpers.s
@@ -512,7 +512,7 @@ itemid_80BF6D8_mail_related: @ 812217C
 	bne _081221A4
 _08122192:
 	adds r0, r4, 0
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0x1
diff --git a/asm/mystery_event_script.s b/asm/mystery_event_script.s
index fbcc5f036..4580ecb87 100644
--- a/asm/mystery_event_script.s
+++ b/asm/mystery_event_script.s
@@ -721,7 +721,7 @@ _08153D86:
 	bl GetMonData
 	lsls r0, 16
 	lsrs r0, 16
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _08153DA4
diff --git a/asm/party_menu.s b/asm/party_menu.s
index 27ff4721c..0ee74ea95 100755
--- a/asm/party_menu.s
+++ b/asm/party_menu.s
@@ -3402,14 +3402,14 @@ sub_81B1DB8: @ 81B1DB8
 	lsrs r4, r5, 16
 	adds r7, r4, 0
 	adds r0, r4, 0
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0x1
 	bne _081B1DE2
 	adds r0, r6, 0
 	adds r1, r4, 0
-	bl sub_80D4420
+	bl GiveMailToMon
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0xFF
@@ -6216,7 +6216,7 @@ _081B34D2:
 	bl GetMonData
 	lsls r0, 16
 	lsrs r0, 16
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _081B3508
@@ -7791,7 +7791,7 @@ _081B425A:
 	.pool
 _081B4278:
 	ldrh r0, [r6]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _081B42A4
@@ -7999,7 +7999,7 @@ _081B4402:
 	.pool
 _081B4458:
 	ldrh r0, [r5]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _081B4498
@@ -8681,7 +8681,7 @@ sub_81B4A98: @ 81B4A98
 	adds r0, r1
 	ldr r1, =sub_81B4AE0
 	movs r2, 0x1
-	bl sub_8121478
+	bl ReadMail
 	pop {r0}
 	bx r0
 	.pool
@@ -8801,7 +8801,7 @@ _081B4BC6:
 	muls r0, r1
 	ldr r1, =gPlayerParty
 	adds r0, r1
-	bl sub_80D4700
+	bl TakeMailFromMon2
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0xFF
@@ -10735,7 +10735,7 @@ sub_81B5CB0: @ 81B5CB0
 	b _081B5D24
 	.pool
 _081B5CD8:
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _081B5CFC
@@ -10821,7 +10821,7 @@ _081B5D68:
 	adds r0, r7, r5
 	ldrb r4, [r0]
 	adds r0, r1, 0
-	bl itemid_is_mail
+	bl ItemIsMail
 	adds r1, r0, 0
 	lsls r1, 24
 	lsrs r1, 24
@@ -10853,7 +10853,7 @@ _081B5DAC:
 	adds r0, r5, r7
 	ldrb r4, [r0, 0x6]
 	adds r0, r1, 0
-	bl itemid_is_mail
+	bl ItemIsMail
 	adds r1, r0, 0
 	lsls r1, 24
 	lsrs r1, 24
@@ -14728,7 +14728,7 @@ sub_81B7FAC: @ 81B7FAC
 	.pool
 _081B7FF8:
 	ldrh r0, [r5]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _081B800C
@@ -14770,7 +14770,7 @@ sub_81B8044: @ 81B8044
 	lsrs r4, r0, 24
 	ldr r5, =gUnknown_0203CEC8
 	ldrh r0, [r5, 0xC]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _081B807C
@@ -15093,7 +15093,7 @@ _081B82FA:
 	.pool
 _081B8338:
 	adds r0, r4, 0
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _081B835C
diff --git a/asm/player_pc.s b/asm/player_pc.s
index c1bb4f632..47cea14f5 100644
--- a/asm/player_pc.s
+++ b/asm/player_pc.s
@@ -1263,7 +1263,7 @@ sub_816B8A4: @ 816B8A4
 	adds r0, r1
 	ldr r1, =sub_816B900
 	movs r2, 0x1
-	bl sub_8121478
+	bl ReadMail
 	adds r0, r4, 0
 	bl DestroyTask
 _0816B8E6:
diff --git a/asm/pokemon_icon.s b/asm/pokemon_icon.s
index 6009bd3f3..79838f6f9 100755
--- a/asm/pokemon_icon.s
+++ b/asm/pokemon_icon.s
@@ -156,7 +156,7 @@ mon_icon_convert_unown_species_id: @ 80D2E08
 	cmp r2, 0xC9
 	bne _080D2E32
 	adds r0, r1, 0
-	bl mon_icon_personality_to_unown_id
+	bl GetUnownLetterByPersonality
 	lsls r0, 16
 	lsrs r0, 16
 	cmp r0, 0
@@ -186,8 +186,8 @@ _080D2E40:
 	bx r1
 	thumb_func_end mon_icon_convert_unown_species_id
 
-	thumb_func_start mon_icon_personality_to_unown_id
-mon_icon_personality_to_unown_id: @ 80D2E48
+	thumb_func_start GetUnownLetterByPersonality
+GetUnownLetterByPersonality: @ 80D2E48
 	push {lr}
 	adds r2, r0, 0
 	cmp r2, 0
@@ -219,7 +219,7 @@ _080D2E7E:
 _080D2E80:
 	pop {r1}
 	bx r1
-	thumb_func_end mon_icon_personality_to_unown_id
+	thumb_func_end GetUnownLetterByPersonality
 
 	thumb_func_start sub_80D2E84
 sub_80D2E84: @ 80D2E84
@@ -229,7 +229,7 @@ sub_80D2E84: @ 80D2E84
 	lsrs r4, r0, 16
 	adds r0, r4, 0
 	mov r1, sp
-	bl sub_80D45E8
+	bl MailSpeciesToSpecies
 	lsls r0, 16
 	lsrs r0, 16
 	cmp r0, 0xC9
diff --git a/asm/pokemon_storage_system.s b/asm/pokemon_storage_system.s
index 2deae56ab..1b93496a7 100755
--- a/asm/pokemon_storage_system.s
+++ b/asm/pokemon_storage_system.s
@@ -2201,7 +2201,7 @@ _080C83CC:
 	ldr r1, =0x00000ce6
 	adds r0, r1
 	ldrh r0, [r0]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _080C83F4
@@ -2304,7 +2304,7 @@ _080C84C8:
 	ldr r1, =0x00000ce6
 	adds r0, r1
 	ldrh r0, [r0]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _080C84F8
@@ -2874,7 +2874,7 @@ _080C8A0C:
 	ldr r2, =0x00000ce6
 	adds r0, r2
 	ldrh r0, [r0]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	bne _080C8A8C
@@ -2913,7 +2913,7 @@ _080C8A7C:
 	ldr r2, =0x00000ce6
 	adds r0, r1, r2
 	ldrh r0, [r0]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _080C8A98
@@ -3661,7 +3661,7 @@ _080C914E:
 	ldr r1, =0x00000ce6
 	adds r0, r1
 	ldrh r0, [r0]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	bne _080C9168
@@ -3943,7 +3943,7 @@ _080C93E4:
 	ldr r1, =0x00000ce6
 	adds r0, r1
 	ldrh r0, [r0]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	bne _080C9404
@@ -16168,7 +16168,7 @@ sub_80CFB44: @ 80CFB44
 	.pool
 _080CFB8C:
 	ldrh r0, [r1]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	bne _080CFBA4
@@ -16197,7 +16197,7 @@ _080CFBAC:
 	.pool
 _080CFBCC:
 	ldrh r0, [r1]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0x1
diff --git a/asm/pokemon_summary_screen.s b/asm/pokemon_summary_screen.s
index f0628ebee..91fd35c1f 100755
--- a/asm/pokemon_summary_screen.s
+++ b/asm/pokemon_summary_screen.s
@@ -4207,7 +4207,7 @@ sub_81C61E0: @ 81C61E0
 	cmp r0, 0x3
 	beq _081C620C
 	ldrh r0, [r4]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0x1
@@ -4673,7 +4673,7 @@ sub_81C6648: @ 81C6648
 	bl sub_81C61A8
 	ldr r5, =gSpecialVar_ItemId
 	ldrh r0, [r5]
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	lsrs r0, 24
 	cmp r0, 0x1
diff --git a/asm/record_mixing.s b/asm/record_mixing.s
index e7d7c8a38..f4271556c 100644
--- a/asm/record_mixing.s
+++ b/asm/record_mixing.s
@@ -3650,7 +3650,7 @@ _080E8A78:
 	beq _080E8A90
 	mov r0, r8
 	movs r1, 0xFC
-	bl sub_81DB4DC
+	bl PadNameString
 _080E8A90:
 	ldrb r1, [r7]
 	lsrs r1, 4
diff --git a/asm/trade.s b/asm/trade.s
index 9f10faee2..10daff6b9 100644
--- a/asm/trade.s
+++ b/asm/trade.s
@@ -13369,7 +13369,7 @@ sub_807E7E8: @ 807E7E8
 	ldrh r0, [r5, 0x28]
 	cmp r0, 0
 	beq _0807E960
-	bl itemid_is_mail
+	bl ItemIsMail
 	lsls r0, 24
 	cmp r0, 0
 	beq _0807E954
@@ -13442,7 +13442,7 @@ _0807E98E:
 	bl StringCopy
 	adds r0, r4, 0
 	movs r1, 0
-	bl sub_81DB4DC
+	bl PadNameString
 	ldr r1, [r6, 0x18]
 	lsrs r0, r1, 24
 	strb r0, [r5, 0x1A]
diff --git a/include/global.h b/include/global.h
index 63bb55165..9fe0d975f 100644
--- a/include/global.h
+++ b/include/global.h
@@ -379,10 +379,12 @@ struct EasyChatPair
     u16 words[2];
 }; /*size = 0x8*/
 
+#define MAIL_WORDS_COUNT 9
+
 struct MailStruct
 {
-    /*0x00*/ u16 words[9];
-    /*0x12*/ u8 playerName[8];
+    /*0x00*/ u16 words[MAIL_WORDS_COUNT];
+    /*0x12*/ u8 playerName[PLAYER_NAME_LENGTH];
     /*0x1A*/ u8 trainerId[4];
     /*0x1E*/ u16 species;
     /*0x20*/ u16 itemId;
diff --git a/include/international_string_util.h b/include/international_string_util.h
index e7876162e..f4ba827e3 100644
--- a/include/international_string_util.h
+++ b/include/international_string_util.h
@@ -14,7 +14,7 @@ s32 sub_81DB3D8(const struct MenuAction *str, u8* arg1, s32 arg2);
 // sub_81DB41C
 // CopyMonCategoryText
 // sub_81DB494
-// sub_81DB4DC
+void PadNameString(u8 *dst, u8 padWith);
 // sub_81DB554
 // sub_81DB5AC
 u32 sub_81DB604(const u8 *);
diff --git a/include/mail.h b/include/mail.h
index 0a70237bf..042586653 100644
--- a/include/mail.h
+++ b/include/mail.h
@@ -14,10 +14,20 @@
                               || itemId == ITEM_FAB_MAIL            \
                               || itemId == ITEM_RETRO_MAIL))
 
+// mail.h
+void ReadMail(struct MailStruct *mail, void (*callback)(void), bool8 flag);
 
+// mail_data.h
+void ClearMailData(void);
+void ClearMailStruct(struct MailStruct *mail);
 bool8 MonHasMail(struct Pokemon *mon);
-void TakeMailFromMon(struct Pokemon *mon);
+u8 GiveMailToMon(struct Pokemon *mon, u16 itemId);
+u16 SpeciesToMailSpecies(u16 species, u32 personality);
+u16 MailSpeciesToSpecies(u16 mailSpecies, u16 *buffer);
 u8 GiveMailToMon2(struct Pokemon *mon, struct MailStruct *mail);
-void ClearMailStruct(struct MailStruct *mail);
+void TakeMailFromMon(struct Pokemon *mon);
+void ClearMailItemId(u8 mailId);
+u8 TakeMailFromMon2(struct Pokemon *mon);
+bool8 ItemIsMail(u16 itemId);
 
 #endif // GUARD_MAIL_H
diff --git a/include/mail_data.h b/include/mail_data.h
deleted file mode 100644
index bf6540bad..000000000
--- a/include/mail_data.h
+++ /dev/null
@@ -1,12 +0,0 @@
-#ifndef GUARD_MAIL_DATA_H
-#define GUARD_MAIL_DATA_H
-
-// Exported type declarations
-
-// Exported RAM declarations
-
-// Exported ROM declarations
-
-u16 sub_80D45E8(u16, u16 *);
-
-#endif //GUARD_MAIL_DATA_H
diff --git a/include/pokemon_icon.h b/include/pokemon_icon.h
index b6d21823e..e0a9aa0c5 100644
--- a/include/pokemon_icon.h
+++ b/include/pokemon_icon.h
@@ -3,6 +3,7 @@
 
 const u8 *GetMonIconPtr(u16 speciesId, u32 personality, u32 frameNo);
 const u16 *GetValidMonIconPalettePtr(u16 speciesId);
+u16 GetUnownLetterByPersonality(u32 personality);
 u16 sub_80D2E84(u16 speciesId);
 void sub_80D2F68(u16 iconId);
 u8 sub_80D2D78(u16 iconId, void callback(struct Sprite *), u16 x, u16 y, u16 a4, u8 a5);
diff --git a/ld_script.txt b/ld_script.txt
index f23954ac0..4015c51fa 100644
--- a/ld_script.txt
+++ b/ld_script.txt
@@ -134,7 +134,7 @@ SECTIONS {
         asm/pokemon_icon.o(.text);
         asm/script_movement.o(.text);
         asm/fldeff_cut.o(.text);
-        asm/mail_data.o(.text);
+        src/mail_data.o(.text);
         asm/map_name_popup.o(.text);
         asm/item_menu_icons.o(.text);
         asm/battle_anim_80D51AC.o(.text);
diff --git a/src/battle_2.c b/src/battle_2.c
index 80945ba8b..7bde3d174 100644
--- a/src/battle_2.c
+++ b/src/battle_2.c
@@ -185,7 +185,7 @@ extern void sub_80356D0(void);
 extern void GetFrontierTrainerName(u8* dst, u16 trainerId); // battle tower
 extern void sub_8166188(void); // battle tower, sets link battle mons level but why?
 extern void sub_8165B88(u8* dst, u16 trainerId); // battle tower, gets language
-extern void sub_81DB4DC(u8* dst, u8 arg2); //
+extern void PadNameString(u8* dst, u8 arg2); //
 extern void sub_81B9150(void);
 extern void sub_800AC34(void);
 extern void sub_80B3AF8(u8 taskId); // cable club
@@ -1140,7 +1140,7 @@ static void sub_80379F8(u8 arrayIdPlus)
         gUnknown_02022FF8[i].gender      = GetMonGender(&gPlayerParty[arrayIdPlus + i]);
         StripExtCtrlCodes(gUnknown_02022FF8[i].nickname);
         if (GetMonData(&gPlayerParty[arrayIdPlus + i], MON_DATA_LANGUAGE) != LANGUAGE_JAPANESE)
-            sub_81DB4DC(gUnknown_02022FF8[i].nickname, 0);
+            PadNameString(gUnknown_02022FF8[i].nickname, CHAR_SPACE);
     }
     memcpy(gUnknown_02023058, gUnknown_02022FF8, sizeof(gUnknown_02022FF8));
 }
diff --git a/src/mail.c b/src/mail.c
index 877035fb6..ec7ff2ce2 100644
--- a/src/mail.c
+++ b/src/mail.c
@@ -1,4 +1,5 @@
 #include "global.h"
+#include "mail.h"
 #include "constants/items.h"
 #include "main.h"
 #include "overworld.h"
@@ -18,8 +19,43 @@
 #include "constants/species.h"
 #include "malloc.h"
 #include "easy_chat.h"
-#include "mail_data.h"
-#include "mail.h"
+
+extern const u16 gUnknown_08DBE818[];
+extern const u16 gUnknown_08DBE838[];
+extern const u16 gUnknown_08DBE858[];
+extern const u16 gUnknown_08DBE878[];
+extern const u16 gUnknown_08DBE898[];
+extern const u16 gUnknown_08DBE8B8[];
+extern const u16 gUnknown_08DBE8D8[];
+extern const u16 gUnknown_08DBE8F8[];
+extern const u16 gUnknown_08DBE918[];
+extern const u16 gUnknown_08DBE938[];
+extern const u16 gUnknown_08DBE958[];
+extern const u16 gUnknown_08DBE978[];
+extern const u8 gUnknown_08DBE998[];
+extern const u8 gUnknown_08DBFBA4[];
+extern const u8 gUnknown_08DBEB38[];
+extern const u8 gUnknown_08DBFC7C[];
+extern const u8 gUnknown_08DBEC74[];
+extern const u8 gUnknown_08DBFD5C[];
+extern const u8 gUnknown_08DBEE84[];
+extern const u8 gUnknown_08DBFE68[];
+extern const u8 gUnknown_08DBEF5C[];
+extern const u8 gUnknown_08DBFF44[];
+extern const u8 gUnknown_08DBF154[];
+extern const u8 gUnknown_08DC0034[];
+extern const u8 gUnknown_08DBF2D4[];
+extern const u8 gUnknown_08DC0114[];
+extern const u8 gUnknown_08DBF37C[];
+extern const u8 gUnknown_08DC01F4[];
+extern const u8 gUnknown_08DBF50C[];
+extern const u8 gUnknown_08DC0300[];
+extern const u8 gUnknown_08DBF64C[];
+extern const u8 gUnknown_08DC03F0[];
+extern const u8 gUnknown_08DBF7B4[];
+extern const u8 gUnknown_08DC04E8[];
+extern const u8 gUnknown_08DBF904[];
+extern const u8 gUnknown_08DC0600[];
 
 // Static type declarations
 
@@ -51,9 +87,7 @@ struct MailGraphics
     u16 color12;
 };
 
-// Static RAM declarations
-
-static EWRAM_DATA struct
+struct MailRead
 {
     /*0x0000*/ u8 strbuf[8][64];
     /*0x0200*/ u8 playerName[12];
@@ -72,22 +106,26 @@ static EWRAM_DATA struct
     /*0x0228*/ const struct MailLayout *layout;
     /*0x022c*/ u8 bg1TilemapBuffer[0x1000];
     /*0x122c*/ u8 bg2TilemapBuffer[0x1000];
-} *gUnknown_0203A134 = NULL;
+};
+
+// Static RAM declarations
+
+static EWRAM_DATA struct MailRead *sMailRead = NULL;
 
 // Static ROM declarations
 
-void sub_81219F0(void);
-void sub_8121A1C(void);
-void sub_8121B1C(void);
-void sub_8121C50(void);
-void sub_8121C64(void);
-void sub_8121C98(void);
-void sub_8121CC0(void);
-void sub_8121D00(void);
+static void CB2_InitMailRead(void);
+static void sub_8121A1C(void);
+static void sub_8121B1C(void);
+static void VBlankCB_MailRead(void);
+static void CB2_MailRead(void);
+static void CB2_WaitForPaletteExitOnKeyPress(void);
+static void CB2_ExitOnKeyPress(void);
+static void CB2_ExitMailReadFreeVars(void);
 
 // .rodata
 
-const struct BgTemplate gUnknown_0859F290[] = {
+static const struct BgTemplate sUnknown_0859F290[] = {
     {
         .bg = 0,
         .charBaseIndex = 2,
@@ -106,7 +144,7 @@ const struct BgTemplate gUnknown_0859F290[] = {
     }
 };
 
-const struct WindowTemplate gUnknown_0859F29C[] = {
+static const struct WindowTemplate sUnknown_0859F29C[] = {
     {
         .priority = 0,
         .tilemapLeft = 2,
@@ -119,55 +157,18 @@ const struct WindowTemplate gUnknown_0859F29C[] = {
     DUMMY_WIN_TEMPLATE
 };
 
-const u8 gUnknown_0859F2AC[] = {
+static const u8 sUnknown_0859F2AC[] = {
      0,
     10,
     11
 };
 
-const u16 gUnknown_0859F2B0[][2] = {
+static const u16 sUnknown_0859F2B0[][2] = {
     { 0x6ACD, 0x51A5 },
     { 0x45FC, 0x38D4 }
 };
 
-extern const u16 gUnknown_08DBE818[];
-extern const u16 gUnknown_08DBE838[];
-extern const u16 gUnknown_08DBE858[];
-extern const u16 gUnknown_08DBE878[];
-extern const u16 gUnknown_08DBE898[];
-extern const u16 gUnknown_08DBE8B8[];
-extern const u16 gUnknown_08DBE8D8[];
-extern const u16 gUnknown_08DBE8F8[];
-extern const u16 gUnknown_08DBE918[];
-extern const u16 gUnknown_08DBE938[];
-extern const u16 gUnknown_08DBE958[];
-extern const u16 gUnknown_08DBE978[];
-extern const u8 gUnknown_08DBE998[];
-extern const u8 gUnknown_08DBFBA4[];
-extern const u8 gUnknown_08DBEB38[];
-extern const u8 gUnknown_08DBFC7C[];
-extern const u8 gUnknown_08DBEC74[];
-extern const u8 gUnknown_08DBFD5C[];
-extern const u8 gUnknown_08DBEE84[];
-extern const u8 gUnknown_08DBFE68[];
-extern const u8 gUnknown_08DBEF5C[];
-extern const u8 gUnknown_08DBFF44[];
-extern const u8 gUnknown_08DBF154[];
-extern const u8 gUnknown_08DC0034[];
-extern const u8 gUnknown_08DBF2D4[];
-extern const u8 gUnknown_08DC0114[];
-extern const u8 gUnknown_08DBF37C[];
-extern const u8 gUnknown_08DC01F4[];
-extern const u8 gUnknown_08DBF50C[];
-extern const u8 gUnknown_08DC0300[];
-extern const u8 gUnknown_08DBF64C[];
-extern const u8 gUnknown_08DC03F0[];
-extern const u8 gUnknown_08DBF7B4[];
-extern const u8 gUnknown_08DC04E8[];
-extern const u8 gUnknown_08DBF904[];
-extern const u8 gUnknown_08DC0600[];
-
-const struct MailGraphics gUnknown_0859F2B8[] = {
+static const struct MailGraphics sUnknown_0859F2B8[] = {
     {
         gUnknown_08DBE818, gUnknown_08DBE998, gUnknown_08DBFBA4, 0x02c0, 0x0000, 0x294a, 0x6739
     }, {
@@ -195,13 +196,13 @@ const struct MailGraphics gUnknown_0859F2B8[] = {
     }
 };
 
-const struct UnkMailStruct Unknown_0859F3A8[] = {
+static const struct UnkMailStruct Unknown_0859F3A8[] = {
     { .numEasyChatWords = 3, .lineHeight = 16 },
     { .numEasyChatWords = 3, .lineHeight = 16 },
     { .numEasyChatWords = 3, .lineHeight = 16 }
 };
 
-const struct MailLayout gUnknown_0859F3B4[] = {
+static const struct MailLayout sUnknown_0859F3B4[] = {
     { 0x03, 0x00, 0x00, 0x02, 0x04, Unknown_0859F3A8 },
     { 0x03, 0x00, 0x00, 0x02, 0x04, Unknown_0859F3A8 },
     { 0x03, 0x00, 0x00, 0x02, 0x04, Unknown_0859F3A8 },
@@ -216,7 +217,7 @@ const struct MailLayout gUnknown_0859F3B4[] = {
     { 0x03, 0x00, 0x00, 0x02, 0x00, Unknown_0859F3A8 }
 };
 
-const struct UnkMailStruct Unknown_0859F444[] = {
+static const struct UnkMailStruct Unknown_0859F444[] = {
     { .numEasyChatWords = 2, .lineHeight = 16 },
     { .numEasyChatWords = 2, .lineHeight = 16 },
     { .numEasyChatWords = 2, .lineHeight = 16 },
@@ -224,7 +225,7 @@ const struct UnkMailStruct Unknown_0859F444[] = {
     { .numEasyChatWords = 1, .lineHeight = 16 }
 };
 
-const struct MailLayout gUnknown_0859F458[] = {
+static const struct MailLayout sUnknown_0859F458[] = {
     { 0x05, 0x07, 0x58, 0x0b, 0x1e, Unknown_0859F444 },
     { 0x05, 0x0a, 0x60, 0x09, 0x1e, Unknown_0859F444 },
     { 0x05, 0x0c, 0x68, 0x05, 0x1e, Unknown_0859F444 },
@@ -241,23 +242,23 @@ const struct MailLayout gUnknown_0859F458[] = {
 
 // What the heck are these meant to be? Call them u16 for now.
 
-const u16 Unknown_0859F4E8[] = {
+static const u16 Unknown_0859F4E8[] = {
     0x00, 0x4000, 0x00, 0x00
 };
 
-const u16 Unknown_0859F4F0[] = {
+static const u16 Unknown_0859F4F0[] = {
     0x00, 0x00, -1, 0x00
 };
 
-const u16 Unknown_0859F4F8[] = {
+static const u16 Unknown_0859F4F8[] = {
     0x04, 0x00, -1, 0x00
 };
 
-const u16 Unknown_0859F500[] = {
+static const u16 Unknown_0859F500[] = {
     0x00, 0x40, -1, 0x00
 };
 
-const u16 *const gUnknown_0859F508[] = {
+static const u16 *const sUnknown_0859F508[] = {
     Unknown_0859F4F0,
     Unknown_0859F4F8,
     Unknown_0859F500
@@ -265,60 +266,62 @@ const u16 *const gUnknown_0859F508[] = {
 
 // .text
 
-void sub_8121478(struct MailStruct *mail, MainCallback callback, bool8 flag) {
+void ReadMail(struct MailStruct *mail, void (*callback)(void), bool8 flag)
+{
     u16 buffer[2];
     u16 species;
 
-    gUnknown_0203A134 = calloc(1, sizeof(*gUnknown_0203A134));
-    gUnknown_0203A134->language = LANGUAGE_ENGLISH;
-    gUnknown_0203A134->playerIsSender = TRUE;
-    gUnknown_0203A134->parserSingle = CopyEasyChatWord;
-    gUnknown_0203A134->parserMultiple = ConvertEasyChatWordsToString;
-    if (mail->itemId >= ITEM_ORANGE_MAIL && mail->itemId <= ITEM_RETRO_MAIL) {
-        gUnknown_0203A134->mailType = mail->itemId - ITEM_ORANGE_MAIL;
+    sMailRead = calloc(1, sizeof(*sMailRead));
+    sMailRead->language = LANGUAGE_ENGLISH;
+    sMailRead->playerIsSender = TRUE;
+    sMailRead->parserSingle = CopyEasyChatWord;
+    sMailRead->parserMultiple = ConvertEasyChatWordsToString;
+    if (IS_ITEM_MAIL(mail->itemId))
+    {
+        sMailRead->mailType = mail->itemId - ITEM_ORANGE_MAIL;
     }
     else
     {
-        gUnknown_0203A134->mailType = 0;
+        sMailRead->mailType = 0;
         flag = FALSE;
     }
-    switch (gUnknown_0203A134->playerIsSender)
+    switch (sMailRead->playerIsSender)
     {
         case FALSE:
         default:
-            gUnknown_0203A134->layout = &gUnknown_0859F3B4[gUnknown_0203A134->mailType];
+            sMailRead->layout = &sUnknown_0859F3B4[sMailRead->mailType];
             break;
         case TRUE:
-            gUnknown_0203A134->layout = &gUnknown_0859F458[gUnknown_0203A134->mailType];
+            sMailRead->layout = &sUnknown_0859F458[sMailRead->mailType];
             break;
     }
-    species = sub_80D45E8(mail->species, buffer);
+    species = MailSpeciesToSpecies(mail->species, buffer);
     if (species >= SPECIES_BULBASAUR && species < NUM_SPECIES)
     {
-        switch (gUnknown_0203A134->mailType)
+        switch (sMailRead->mailType)
         {
             default:
-                gUnknown_0203A134->animsActive = 0;
+                sMailRead->animsActive = 0;
                 break;
             case ITEM_BEAD_MAIL - ITEM_ORANGE_MAIL:
-                gUnknown_0203A134->animsActive = 1;
+                sMailRead->animsActive = 1;
                 break;
             case ITEM_DREAM_MAIL - ITEM_ORANGE_MAIL:
-                gUnknown_0203A134->animsActive = 2;
+                sMailRead->animsActive = 2;
                 break;
         }
     }
     else
     {
-        gUnknown_0203A134->animsActive = 0;
+        sMailRead->animsActive = 0;
     }
-    gUnknown_0203A134->mail = mail;
-    gUnknown_0203A134->callback = callback;
-    gUnknown_0203A134->flag = flag;
-    SetMainCallback2(sub_81219F0);
+    sMailRead->mail = mail;
+    sMailRead->callback = callback;
+    sMailRead->flag = flag;
+    SetMainCallback2(CB2_InitMailRead);
 }
 
-bool8 sub_81215EC(void)
+static bool8 MailReadBuildGraphics(void)
 {
     u16 icon;
 
@@ -352,21 +355,21 @@ bool8 sub_81215EC(void)
             SetGpuReg(REG_OFFSET_BG2HOFS, 0x0000);
             SetGpuReg(REG_OFFSET_BG3HOFS, 0x0000);
             SetGpuReg(REG_OFFSET_BG3VOFS, 0x0000);
-            SetGpuReg(REG_OFFSET_BLDCNT, 0x0000);
+            SetGpuReg(REG_OFFSET_BLDCNT,  0x0000);
             SetGpuReg(REG_OFFSET_BLDALPHA, 0x0000);
             break;
         case 6:
             ResetBgsAndClearDma3BusyFlags(0);
-            InitBgsFromTemplates(0, gUnknown_0859F290, 3);
-            SetBgTilemapBuffer(1, gUnknown_0203A134->bg1TilemapBuffer);
-            SetBgTilemapBuffer(2, gUnknown_0203A134->bg2TilemapBuffer);
+            InitBgsFromTemplates(0, sUnknown_0859F290, 3);
+            SetBgTilemapBuffer(1, sMailRead->bg1TilemapBuffer);
+            SetBgTilemapBuffer(2, sMailRead->bg2TilemapBuffer);
             break;
         case 7:
-            InitWindows(gUnknown_0859F29C);
+            InitWindows(sUnknown_0859F29C);
             DeactivateAllTextPrinters();
             break;
         case 8:
-            decompress_and_copy_tile_data_to_vram(1, gUnknown_0859F2B8[gUnknown_0203A134->mailType].tiles, 0, 0, 0);
+            decompress_and_copy_tile_data_to_vram(1, sUnknown_0859F2B8[sMailRead->mailType].tiles, 0, 0, 0);
             break;
         case 9:
             if (free_temp_tile_data_buffers_if_possible())
@@ -377,7 +380,7 @@ bool8 sub_81215EC(void)
         case 10:
             FillBgTilemapBufferRect_Palette0(0, 0, 0, 0, 30, 20);
             FillBgTilemapBufferRect_Palette0(2, 1, 0, 0, 30, 20);
-            CopyToBgTilemapBuffer(1, gUnknown_0859F2B8[gUnknown_0203A134->mailType].tileMap, 0, 0);
+            CopyToBgTilemapBuffer(1, sUnknown_0859F2B8[sMailRead->mailType].tileMap, 0, 0);
             break;
         case 11:
             CopyBgTilemapBufferToVram(0);
@@ -386,24 +389,24 @@ bool8 sub_81215EC(void)
             break;
         case 12:
             LoadPalette(GetOverworldTextboxPalettePtr(), 240, 32);
-            gPlttBufferUnfaded[250] = gUnknown_0859F2B8[gUnknown_0203A134->mailType].color10;
-            gPlttBufferFaded[250] = gUnknown_0859F2B8[gUnknown_0203A134->mailType].color10;
-            gPlttBufferUnfaded[251] = gUnknown_0859F2B8[gUnknown_0203A134->mailType].color12;
-            gPlttBufferFaded[251] = gUnknown_0859F2B8[gUnknown_0203A134->mailType].color12;
-            LoadPalette(gUnknown_0859F2B8[gUnknown_0203A134->mailType].palette, 0, 32);
-            gPlttBufferUnfaded[10] = gUnknown_0859F2B0[gSaveBlock2Ptr->playerGender][0];
-            gPlttBufferFaded[10] = gUnknown_0859F2B0[gSaveBlock2Ptr->playerGender][0];
-            gPlttBufferUnfaded[11] = gUnknown_0859F2B0[gSaveBlock2Ptr->playerGender][1];
-            gPlttBufferFaded[11] = gUnknown_0859F2B0[gSaveBlock2Ptr->playerGender][1];
+            gPlttBufferUnfaded[250] = sUnknown_0859F2B8[sMailRead->mailType].color10;
+            gPlttBufferFaded[250] = sUnknown_0859F2B8[sMailRead->mailType].color10;
+            gPlttBufferUnfaded[251] = sUnknown_0859F2B8[sMailRead->mailType].color12;
+            gPlttBufferFaded[251] = sUnknown_0859F2B8[sMailRead->mailType].color12;
+            LoadPalette(sUnknown_0859F2B8[sMailRead->mailType].palette, 0, 32);
+            gPlttBufferUnfaded[10] = sUnknown_0859F2B0[gSaveBlock2Ptr->playerGender][0];
+            gPlttBufferFaded[10] = sUnknown_0859F2B0[gSaveBlock2Ptr->playerGender][0];
+            gPlttBufferUnfaded[11] = sUnknown_0859F2B0[gSaveBlock2Ptr->playerGender][1];
+            gPlttBufferFaded[11] = sUnknown_0859F2B0[gSaveBlock2Ptr->playerGender][1];
             break;
         case 13:
-            if (gUnknown_0203A134->flag)
+            if (sMailRead->flag)
             {
                 sub_8121A1C();
             }
             break;
         case 14:
-            if (gUnknown_0203A134->flag)
+            if (sMailRead->flag)
             {
                 sub_8121B1C();
                 RunTextPrinters();
@@ -416,20 +419,20 @@ bool8 sub_81215EC(void)
             }
             break;
         case 16:
-            SetVBlankCallback(sub_8121C50);
+            SetVBlankCallback(VBlankCB_MailRead);
             gPaletteFade.bufferTransferDisabled = TRUE;
             break;
         case 17:
-            icon = sub_80D2E84(gUnknown_0203A134->mail->species);
-            switch (gUnknown_0203A134->animsActive)
+            icon = sub_80D2E84(sMailRead->mail->species);
+            switch (sMailRead->animsActive)
             {
                 case 1:
                     sub_80D2F68(icon);
-                    gUnknown_0203A134->monIconSprite = sub_80D2D78(icon, SpriteCallbackDummy, 0x60, 0x80, 0, 0);
+                    sMailRead->monIconSprite = sub_80D2D78(icon, SpriteCallbackDummy, 0x60, 0x80, 0, 0);
                     break;
                 case 2:
                     sub_80D2F68(icon);
-                    gUnknown_0203A134->monIconSprite = sub_80D2D78(icon, SpriteCallbackDummy, 0x28, 0x80, 0, 0);
+                    sMailRead->monIconSprite = sub_80D2D78(icon, SpriteCallbackDummy, 0x28, 0x80, 0, 0);
                     break;
             }
             break;
@@ -440,53 +443,53 @@ bool8 sub_81215EC(void)
             ShowBg(2);
             BeginNormalPaletteFade(-1, 0, 16, 0, 0);
             gPaletteFade.bufferTransferDisabled = FALSE;
-            gUnknown_0203A134->callback2 = sub_8121C98;
+            sMailRead->callback2 = CB2_WaitForPaletteExitOnKeyPress;
             return TRUE;
         default:
             return FALSE;
     }
-    gMain.state ++;
+    gMain.state++;
     return FALSE;
 }
 
-void sub_81219F0(void)
+static void CB2_InitMailRead(void)
 {
     do
     {
-        if (sub_81215EC() == TRUE)
+        if (MailReadBuildGraphics() == TRUE)
         {
-            SetMainCallback2(sub_8121C64);
+            SetMainCallback2(CB2_MailRead);
             break;
         }
     } while (sub_81221AC() != TRUE);
 }
 
-void sub_8121A1C(void)
+static void sub_8121A1C(void)
 {
     u16 i;
     u8 total;
     u8 *ptr;
 
     total = 0;
-    for (i = 0; i < gUnknown_0203A134->layout->numSubStructs; i ++)
+    for (i = 0; i < sMailRead->layout->numSubStructs; i ++)
     {
-        ConvertEasyChatWordsToString(gUnknown_0203A134->strbuf[i], &gUnknown_0203A134->mail->words[total], gUnknown_0203A134->layout->var8[i].numEasyChatWords, 1);
-        total += gUnknown_0203A134->layout->var8[i].numEasyChatWords;
+        ConvertEasyChatWordsToString(sMailRead->strbuf[i], &sMailRead->mail->words[total], sMailRead->layout->var8[i].numEasyChatWords, 1);
+        total += sMailRead->layout->var8[i].numEasyChatWords;
     }
-    ptr = StringCopy(gUnknown_0203A134->playerName, gUnknown_0203A134->mail->playerName);
-    if (!gUnknown_0203A134->playerIsSender)
+    ptr = StringCopy(sMailRead->playerName, sMailRead->mail->playerName);
+    if (!sMailRead->playerIsSender)
     {
         StringCopy(ptr, gText_FromSpace);
-        gUnknown_0203A134->signatureWidth = gUnknown_0203A134->layout->signatureWidth - (StringLength(gUnknown_0203A134->playerName) * 8 - 0x60);
+        sMailRead->signatureWidth = sMailRead->layout->signatureWidth - (StringLength(sMailRead->playerName) * 8 - 0x60);
     }
     else
     {
-        sub_81DB52C(gUnknown_0203A134->playerName);
-        gUnknown_0203A134->signatureWidth = gUnknown_0203A134->layout->signatureWidth;
+        sub_81DB52C(sMailRead->playerName);
+        sMailRead->signatureWidth = sMailRead->layout->signatureWidth;
     }
 }
 
-void sub_8121B1C(void)
+static void sub_8121B1C(void)
 {
     u16 i;
     u8 strbuf[0x20];
@@ -500,77 +503,76 @@ void sub_8121B1C(void)
     PutWindowTilemap(1);
     FillWindowPixelBuffer(0, 0);
     FillWindowPixelBuffer(1, 0);
-    for (i = 0; i < gUnknown_0203A134->layout->numSubStructs; i ++)
+    for (i = 0; i < sMailRead->layout->numSubStructs; i ++)
     {
-        if (gUnknown_0203A134->strbuf[i][0] == EOS || gUnknown_0203A134->strbuf[i][0] == CHAR_SPACE)
+        if (sMailRead->strbuf[i][0] == EOS || sMailRead->strbuf[i][0] == CHAR_SPACE)
         {
             continue;
         }
-        box_print(0, 1, gUnknown_0203A134->layout->var8[i].xOffset + gUnknown_0203A134->layout->wordsYPos, y + gUnknown_0203A134->layout->wordsXPos, gUnknown_0859F2AC, 0, gUnknown_0203A134->strbuf[i]);
-        y += gUnknown_0203A134->layout->var8[i].lineHeight;
+        box_print(0, 1, sMailRead->layout->var8[i].xOffset + sMailRead->layout->wordsYPos, y + sMailRead->layout->wordsXPos, sUnknown_0859F2AC, 0, sMailRead->strbuf[i]);
+        y += sMailRead->layout->var8[i].lineHeight;
     }
     bufptr = StringCopy(strbuf, gText_FromSpace);
-    StringCopy(bufptr, gUnknown_0203A134->playerName);
-    box_x = GetStringCenterAlignXOffset(1, strbuf, gUnknown_0203A134->signatureWidth) + 0x68;
-    box_y = gUnknown_0203A134->layout->signatureYPos + 0x58;
-    box_print(0, 1, box_x, box_y, gUnknown_0859F2AC, 0, strbuf);
+    StringCopy(bufptr, sMailRead->playerName);
+    box_x = GetStringCenterAlignXOffset(1, strbuf, sMailRead->signatureWidth) + 0x68;
+    box_y = sMailRead->layout->signatureYPos + 0x58;
+    box_print(0, 1, box_x, box_y, sUnknown_0859F2AC, 0, strbuf);
     CopyWindowToVram(0, 3);
     CopyWindowToVram(1, 3);
 }
 
-void sub_8121C50(void)
+static void VBlankCB_MailRead(void)
 {
     LoadOam();
     ProcessSpriteCopyRequests();
     TransferPlttBuffer();
 }
 
-void sub_8121C64(void)
+static void CB2_MailRead(void)
 {
-    if (gUnknown_0203A134->animsActive != 0)
+    if (sMailRead->animsActive != 0)
     {
         AnimateSprites();
         BuildOamBuffer();
     }
-    gUnknown_0203A134->callback2();
+    sMailRead->callback2();
 }
 
-void sub_8121C98(void)
+static void CB2_WaitForPaletteExitOnKeyPress(void)
 {
     if (!UpdatePaletteFade())
     {
-        gUnknown_0203A134->callback2 = sub_8121CC0;
+        sMailRead->callback2 = CB2_ExitOnKeyPress;
     }
 }
 
-void sub_8121CC0(void)
+static void CB2_ExitOnKeyPress(void)
 {
     if (gMain.newKeys & (A_BUTTON | B_BUTTON))
     {
         BeginNormalPaletteFade(-1, 0, 0, 16, 0);
-        gUnknown_0203A134->callback2 = sub_8121D00;
+        sMailRead->callback2 = CB2_ExitMailReadFreeVars;
     }
 }
 
-void sub_8121D00(void)
+static void CB2_ExitMailReadFreeVars(void)
 {
     if (!UpdatePaletteFade())
     {
-        SetMainCallback2(gUnknown_0203A134->callback);
-        switch (gUnknown_0203A134->animsActive)
+        SetMainCallback2(sMailRead->callback);
+        switch (sMailRead->animsActive)
         {
             case 1:
             case 2:
-                sub_80D2FF0(sub_80D2E84(gUnknown_0203A134->mail->species));
-                sub_80D2EF8(&gSprites[gUnknown_0203A134->monIconSprite]);
+                sub_80D2FF0(sub_80D2E84(sMailRead->mail->species));
+                sub_80D2EF8(&gSprites[sMailRead->monIconSprite]);
         }
-        memset(gUnknown_0203A134, 0, sizeof(*gUnknown_0203A134));
+        memset(sMailRead, 0, sizeof(*sMailRead));
         ResetPaletteFade();
         UnsetBgTilemapBuffer(0);
         UnsetBgTilemapBuffer(1);
         ResetBgsAndClearDma3BusyFlags(0);
         FreeAllWindowBuffers();
-        free(gUnknown_0203A134);
-        gUnknown_0203A134 = NULL;
+        FREE_AND_SET_NULL(sMailRead);
     }
 }
diff --git a/src/mail_data.c b/src/mail_data.c
new file mode 100644
index 000000000..ebb49febf
--- /dev/null
+++ b/src/mail_data.c
@@ -0,0 +1,203 @@
+#include "global.h"
+#include "mail.h"
+#include "constants/items.h"
+#include "pokemon.h"
+#include "pokemon_icon.h"
+#include "constants/species.h"
+#include "text.h"
+#include "international_string_util.h"
+
+void ClearMailData(void)
+{
+    u8 i;
+
+    for (i = 0; i < MAIL_COUNT; i++)
+        ClearMailStruct(&gSaveBlock1Ptr->mail[i]);
+}
+
+void ClearMailStruct(struct MailStruct *mail)
+{
+    s32 i;
+
+    for (i = 0; i < MAIL_WORDS_COUNT; i++)
+        mail->words[i] = 0xFFFF;
+
+    for (i = 0; i < PLAYER_NAME_LENGTH; i++)
+        mail->playerName[i] = EOS;
+
+    for (i = 0; i < 4; i++)
+        mail->trainerId[i] = 0;
+
+    mail->species = SPECIES_BULBASAUR;
+    mail->itemId = ITEM_NONE;
+}
+
+bool8 MonHasMail(struct Pokemon *mon)
+{
+    u16 heldItem = GetMonData(mon, MON_DATA_HELD_ITEM);
+    if (ItemIsMail(heldItem) && GetMonData(mon, MON_DATA_MAIL) != 0xFF)
+        return TRUE;
+    else
+        return FALSE;
+}
+
+u8 GiveMailToMon(struct Pokemon *mon, u16 itemId)
+{
+    u8 heldItem[2];
+    u8 id, i;
+    u16 species;
+    u32 personality;
+
+    heldItem[0] = itemId;
+    heldItem[1] = itemId >> 8;
+
+    for (id = 0; id < PARTY_SIZE; id++)
+    {
+        if (gSaveBlock1Ptr->mail[id].itemId == 0)
+        {
+            for (i = 0; i < MAIL_WORDS_COUNT; i++)
+                gSaveBlock1Ptr->mail[id].words[i] = 0xFFFF;
+
+            for (i = 0; i < PLAYER_NAME_LENGTH - 1; i++)
+                gSaveBlock1Ptr->mail[id].playerName[i] = gSaveBlock2Ptr->playerName[i];
+            gSaveBlock1Ptr->mail[id].playerName[i] = EOS;
+            PadNameString(gSaveBlock1Ptr->mail[id].playerName, CHAR_SPACE);
+
+            for (i = 0; i < 4; i++)
+                gSaveBlock1Ptr->mail[id].trainerId[i] = gSaveBlock2Ptr->playerTrainerId[i];
+
+            species = GetBoxMonData(&mon->box, MON_DATA_SPECIES);
+            personality = GetBoxMonData(&mon->box, MON_DATA_PERSONALITY);
+            gSaveBlock1Ptr->mail[id].species = SpeciesToMailSpecies(species, personality);
+            gSaveBlock1Ptr->mail[id].itemId = itemId;
+            SetMonData(mon, MON_DATA_MAIL, &id);
+            SetMonData(mon, MON_DATA_HELD_ITEM, heldItem);
+            return id;
+        }
+    }
+
+    return 0xFF;
+}
+
+u16 SpeciesToMailSpecies(u16 species, u32 personality)
+{
+    if (species == SPECIES_UNOWN)
+    {
+        u32 species = GetUnownLetterByPersonality(personality) + 30000;
+        return species;
+    }
+
+    return species;
+}
+
+u16 MailSpeciesToSpecies(u16 mailSpecies, u16 *buffer)
+{
+    u16 result;
+
+    if (mailSpecies >= 30000 && mailSpecies < (30000 + UNOWN_FORM_COUNT))
+    {
+        result = SPECIES_UNOWN;
+        *buffer = mailSpecies - 30000;
+    }
+    else
+    {
+        result = mailSpecies;
+    }
+
+    return result;
+}
+
+u8 GiveMailToMon2(struct Pokemon *mon, struct MailStruct *mail)
+{
+    u8 heldItem[2];
+    u16 itemId = mail->itemId;
+    u8 mailId = GiveMailToMon(mon, itemId);
+
+    if (mailId == 0xFF)
+        return 0xFF;
+
+    gSaveBlock1Ptr->mail[mailId] = *mail;
+
+    SetMonData(mon, MON_DATA_MAIL, &mailId);
+
+    heldItem[0] = itemId;
+    heldItem[1] = itemId >> 8;
+
+    SetMonData(mon, MON_DATA_HELD_ITEM, heldItem);
+
+    return mailId;
+}
+
+static bool32 DummyMailFunc(void)
+{
+    return FALSE;
+}
+
+void TakeMailFromMon(struct Pokemon *mon)
+{
+    u8 heldItem[2];
+    u8 mailId;
+
+    if (MonHasMail(mon))
+    {
+        mailId = GetMonData(mon, MON_DATA_MAIL);
+        gSaveBlock1Ptr->mail[mailId].itemId = ITEM_NONE;
+        mailId = 0xFF;
+        heldItem[0] = ITEM_NONE;
+        heldItem[1] = ITEM_NONE << 8;
+        SetMonData(mon, MON_DATA_MAIL, &mailId);
+        SetMonData(mon, MON_DATA_HELD_ITEM, heldItem);
+    }
+}
+
+void ClearMailItemId(u8 mailId)
+{
+    gSaveBlock1Ptr->mail[mailId].itemId = ITEM_NONE;
+}
+
+u8 TakeMailFromMon2(struct Pokemon *mon)
+{
+    u8 i;
+    u8 newHeldItem[2];
+    u8 newMailId;
+
+    newHeldItem[0] = ITEM_NONE;
+    newHeldItem[1] = ITEM_NONE << 8;
+    newMailId = 0xFF;
+
+    for (i = PARTY_SIZE; i < MAIL_COUNT; i++)
+    {
+        if (gSaveBlock1Ptr->mail[i].itemId == ITEM_NONE)
+        {
+            memcpy(&gSaveBlock1Ptr->mail[i], &gSaveBlock1Ptr->mail[GetMonData(mon, MON_DATA_MAIL)], sizeof(struct MailStruct));
+            gSaveBlock1Ptr->mail[GetMonData(mon, MON_DATA_MAIL)].itemId = ITEM_NONE;
+            SetMonData(mon, MON_DATA_MAIL, &newMailId);
+            SetMonData(mon, MON_DATA_HELD_ITEM, newHeldItem);
+            return i;
+        }
+    }
+
+    return 0xFF;
+}
+
+bool8 ItemIsMail(u16 itemId)
+{
+    switch (itemId)
+    {
+    case ITEM_ORANGE_MAIL:
+    case ITEM_HARBOR_MAIL:
+    case ITEM_GLITTER_MAIL:
+    case ITEM_MECH_MAIL:
+    case ITEM_WOOD_MAIL:
+    case ITEM_WAVE_MAIL:
+    case ITEM_BEAD_MAIL:
+    case ITEM_SHADOW_MAIL:
+    case ITEM_TROPIC_MAIL:
+    case ITEM_DREAM_MAIL:
+    case ITEM_FAB_MAIL:
+    case ITEM_RETRO_MAIL:
+        return TRUE;
+    default:
+        return FALSE;
+    }
+}