Initialize_Entities:
	LD A, $mem_bunny_mana
	LD C, A
	LD A, $mem_bunny_health
	LD B, A
	LD HL, $mem_entities_list
	Clear_Entities.loop:
		XOR A
		LD (HL+), A
		CP L
		JR NZ, =Clear_Entities.loop

	LD A, B
	LD $mem_bunny_health, A

	LD A, C
	LD $mem_bunny_mana, A

	LD HL, $mem_entities_list
	LD A, $01
	LD (HL+), A

	LD A, $mem_number_of_rooms
	CALL =RNG_Bound
	SLA A
	SLA A
	ADD low($mem_room_list)
	LD C, A

	LD B, high($mem_room_list)

	LD A, (BC)
	LD D, A
	INC BC
	LD A, (BC)
	INC A
	CALL =RNG_Bound
	ADD D

	LD (HL+), A

	INC BC

	LD A, (BC)
	LD D, A
	INC BC
	LD A, (BC)
	INC A
	CALL =RNG_Bound
	ADD D

	LD (HL), A

	PUSH BC
	LD C, (HL)
	DEC HL
	LD B, (HL)
	INC HL

	CALL =Carve_Entity_Collision_Map

	POP BC

	INC HL

	LD A, $enum_direction_down
	LD (HL+), A

	; Turn
	LD A, $01
	LD (HL+), A

	; Action
	LD A, $00
	LD (HL+), A

	INC HL ; skip health

	LD A, $00

	; Flags
	LD (HL+), A

	; Status
	LD (HL+), A

	LD A, L
	AND $f0
	ADD $10
	LD L, A

	LD A, $00
	LD $mem_enemies_alive_count, A

	LD A, $ff
	LD $mem_bunny_current_room_idx, A

	LD A, $00
	LD $tmp_var_3, A
	CALL =Initialize_Enemy
	CALL =Initialize_Enemy
	CALL =Initialize_Enemy
	CALL =Initialize_Enemy
	CALL =Initialize_Enemy
	CALL =Reset_Entities_Collision_Map

Fix_Bunny_screen:
	LD A, $mem_bunny_x
	SUB $05
	LD $mem_viewport_x, A

	LD A, $mem_bunny_y
	SUB $04
	LD $mem_viewport_y, A

	LD A, $mem_viewport_x
	SWAP A
	AND $f0
	OR $08
	LD $mem_prepared_viewport_x, A

	LD A, $mem_viewport_y
	SWAP A
	AND $f0
	OR $08
	LD $mem_prepared_viewport_y, A

	RET

Initialize_Enemy: ; HL => pointer to entity struct
	CALL =Enemy_idx_to_spawn
	CP $ff
	RET Z
	ADD $03

Initialize_Entity: ; HL => pointer to entity struct, A => entity loaded index, 1 in $tmp_var_3 if should retry if collsion (could potentially fail multiple time/infinite loop)
	LD E, A
	SLA A
	SLA A
	LD B, A
	SLA A
	ADD B
	INC A
	LD (HL+), A

	LD A, $mem_bunny_current_room_idx
	LD $tmp_var_6, A
	CP $FF
	JR Z, =Initialize_Enemy.All_rooms_allowed
	LD B, A
	Initialize_Enemy.Skip_bunny_room:
		LD A, $mem_number_of_rooms
		CP $01
		JR Z, =Initialize_Enemy.All_rooms_allowed

		DEC A
		CALL =RNG_Bound
		LD $tmp_var_5, A
		INC A
		LD C, A
		LD A, B
		CP C
		LD A, C
		JR C, =Initialize_Enemy.Room_restriction.end
		DEC A

		JR =Initialize_Enemy.Room_restriction.end

	Initialize_Enemy.All_rooms_allowed:
		LD A, $mem_number_of_rooms
		CALL =RNG_Bound
	Initialize_Enemy.Room_restriction.end:
	LD $tmp_var_4, A
	SLA A
	SLA A
	ADD low($mem_room_list)
	LD C, A

	LD B, high($mem_room_list)

	; X
	LD A, (BC)
	LD D, A
	INC BC
	LD A, (BC)
	INC A
	CALL =RNG_Bound
	ADD D

	LD (HL+), A

	INC BC

	; Y
	LD A, (BC)
	LD D, A
	INC BC
	LD A, (BC)
	INC A
	CALL =RNG_Bound
	ADD D
	LD (HL), A

	; Check if spawning on collisionable tile
	PUSH BC
	LD C, (HL)
	DEC HL
	LD B, (HL)
	INC HL

	CALL =Is_Collisionable
	CP $00
	JR Z, =.no_collision

	XOR A
	LD (HL-), A
	LD (HL-), A
	LD (HL), A

	POP BC

	LD A, $tmp_var_3
	CP $01

	RET NZ

	LD A, E
	JP =Initialize_Entity

	.no_collision:
	CALL =Carve_Entity_Collision_Map

	POP BC

	INC HL

	; Direction
	LD A, $03
	LD (HL+), A

	LD A, E
	CALL =Entity_idx_to_entity_list_ptr
	INC BC
	INC BC

	; Turn
	LD A, (BC)
	LD (HL+), A

	INC BC

	; Action
	LD A, (BC)
	LD (HL+), A

	INC BC

	; Health
	LD A, (BC)
	LD (HL+), A

	INC BC

	XOR A
	; flags & status
	LD (HL+), A

	LD A, (BC)
	LD (HL+), A

	INC BC

	; Mana
	LD A, (BC)
	LD (HL+), A

	LD A, L
	ADD $06
	LD L, A

	LD A, E
	CP $03
	RET C

	CP $07
	RET NC

	LD A, $mem_enemies_alive_count
	INC A
	LD $mem_enemies_alive_count, A
	RET

FindFreeEntity:
	LD HL, $mem_entities_list
	FindFreeEntity.loop:
		; This loop supposes that there is indeed enough space for a new entity
		; to be spawn (thus the previous mem_enemies_alive_count).
		; If entities are changed at some point to contain things that are not
		; counted in mem_enemies_alive_count, this could result in an infinite loop.
		; (Technically the quest goals can spawn other entities. We assume that the enemies alive count and the quest goal entities spawned will never exceed 15 together)
		LD A, L
		AND $f0
		ADD $10
		LD L, A

		LD A, $00
		CP (HL)
		JR NZ, =FindFreeEntity.loop
	RET

Respawn_Entities:
	LD A, $mem_moving_animation_step
	CP $04
	RET NZ

	LD A, $mem_enemies_alive_count
	CP $05
	RET NC

	LD A, $00
	LD $tmp_var_3, A

	CALL =RNG_Step
	AND $07
	CP $00
	RET NZ

	CALL =FindFreeEntity

	CALL =Initialize_Enemy
	RET

Enemy_spawn_pattern_to_probability: ; (1/(x + 1))
	.DB 0b11111111
	.DB 0b00000111
	.DB 0b00000001
	.DB 0b00000000

Enemy_idx_to_spawn: ; Return in A, ff if no entity to be spawned
	PUSH BC

	LD A, $mem_entity_spawning_pattern
	LD B, A

	CALL =RNG_Step
	AND $03
	LD C, A
	SLA A
	CALL =RRx
	LD A, B
	AND $03

	PUSH DE
	LD DE, =Enemy_spawn_pattern_to_probability
	ADD E
	LD E, A
	LD A, D
	ADC $00
	LD D, A
	LD A, (DE)
	POP DE

	LD B, A
	CALL =RNG_Step
	AND B
	CP $00
	LD A, $ff
	JR NZ, =.skip_set_enemy_idx

	LD A, C

	.skip_set_enemy_idx:

	POP BC
	RET

.MACRODEF GET_ENTITY_IDX_SPAWN_RATE idx ; breaks BC & A
	LD A, low($idx)
	CALL =Entity_idx_to_entity_list_ptr
	LD A, C
	ADD $07
	LD C, A
	LD A, B
	ADC $00
	LD B, A
	LD A, (BC)
	AND $03
.END