Krakout: Quit-confirmation handler (per-frame)

8D9C: Quit-confirmation handler (per-frame)

Offers the ARE YOU SURE Y-N? prompt when Q is pressed, and abandons the game on Y. The prompt blocks the frame until the player answers.
Q held: blip to acknowledge, then draw the two-line prompt beside the bat. Its column comes from the bat side, so the text lands on the wall the bat occupies. Wait for Q to be released, then poll the Y and N keys until one answers. Y discards the call stack and jumps to the restart entry. N erases the prompt and returns. The prompt is two single-height font lines one character row apart. The N-key path erases both at once with a single double-height blank string.
handle_quit_confirm	8D9C	CALL poll_quit_key	Return unless the Q key is held this frame.
	8D9F	OR A
	8DA0	RET Z
	8DA1	CALL sfx_key_blip	Blip to acknowledge the Q press.
	8DA4	LD A,(bat_side)	Pick the prompt's line-1 cell so it sits on the bat's side: the bat on the left takes column 2.
	8DA7	OR A
	8DA8	JR Z,handle_quit_confirm_0
	8DAA	LD HL,SCREEN_BASE+$882
	8DAD	JR handle_quit_confirm_1
handle_quit_confirm_0	8DAF	LD HL,SCREEN_BASE+$894	A zero side takes column 20 instead.
handle_quit_confirm_1	8DB2	PUSH HL	Keep the line-1 cell for line 2 and the later erase.
	8DB3	LD DE,msg_are_you_sure	Print line 1 in bright white on black.
	8DB6	LD C,$47
	8DB8	CALL print_string
	8DBB	POP HL	Reload the line-1 cell and keep it saved.
	8DBC	PUSH HL	Reload the line-1 cell and keep it saved.
	8DBD	LD DE,$0020	Step down one character row (32 cells) to line 2.
	8DC0	ADD HL,DE	Step down one character row (32 cells) to line 2.
	8DC1	LD DE,msg_sure_yn	Print line 2.
	8DC4	LD C,$47
	8DC6	CALL print_string
wait_q_release	8DC9	CALL poll_quit_key	Wait for the Q key to be released before it reads the answer.
	8DCC	OR A
	8DCD	JR NZ,wait_q_release
poll_quit_answer	8DCF	LD BC,KBD_ROW_Y_P	Read the P-Y keyboard half-row and keep the 5 key bits.
	8DD2	IN A,(C)
	8DD4	AND $1F
	8DD6	BIT 4,A	Bit 4 is the Y key (0 when pressed).
	8DD8	JR NZ,poll_quit_no_key	Y up: go test the N key.
	8DDA	CALL sfx_key_blip	Y pressed: blip to confirm the quit.
	8DDD	POP HL	Discard the saved cell and the caller's return address – the call chain is abandoned.
	8DDE	POP HL
	8DDF	JP new_game	Restart a fresh game from the restart entry.
poll_quit_no_key	8DE2	LD B,$7F	Switch BC to the B-Space half-row and keep the 5 key bits.
	8DE4	IN A,(C)
	8DE6	AND $1F
	8DE8	BIT 3,A	Bit 3 is the N key (0 when pressed).
	8DEA	JR NZ,poll_quit_answer	Neither Y nor N pressed: poll again for an answer.
	8DEC	CALL sfx_key_blip	N pressed: blip and resume play.
	8DEF	POP HL	Recover the line-1 cell, then erase both lines with one double-height blank.
	8DF0	LD DE,msg_sure_pad
	8DF3	LD C,$47
	8DF5	CALL print_string_2x
	8DF8	RET

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