From a6adf07fc704f3e17f756673b94ddae78bee1473 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Juhani=20Krekel=C3=A4?= <juhani@krekelä.fi>
Date: Fri, 25 Feb 2022 01:40:59 +0200
Subject: [PATCH] Add ultra hard mode

---
 README.md |  1 -
 dosdl.asm | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 60 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index bce613c..edf15ce 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,6 @@ Missing features
 ----------------
 
 - Ability to set the seed manually
-- Hard and extra hard modes
 
 Word lists
 ----------
diff --git a/dosdl.asm b/dosdl.asm
index 91bac69..f42dba8 100644
--- a/dosdl.asm
+++ b/dosdl.asm
@@ -306,6 +306,51 @@ check_ultra_hard_mode:
 	cmp byte [ultra_hard_mode], 1
 	jne .done
 
+	; See whether any ruled-out letters were used
+	xor bp, bp
+	mov cx, 5
+	.ruled_out:
+		xor bh, bh
+		mov bl, [guess + bp]
+		mov ax, bx
+		mov al, [alphabet + bx - 'a']
+		cmp al, ' '
+		jne .not_ruled_out
+
+		mov [ruled_out_error_str.letter], bl
+		mov ax, bp
+		add al, '1'
+		mov [ruled_out_error_str.position], al
+		mov si, ruled_out_error_str
+		jmp print_error
+
+		.not_ruled_out:
+		inc bp
+		loop .ruled_out
+
+	; See whether wrongly places letters were moved
+	xor bp, bp
+	mov cx, 5
+	.wrong_places:
+		mov al, [wrong_places + bp]
+		test al, al
+		jz .not_wrong_place
+
+		cmp al, [guess + bp]
+		jne .moved
+
+		mov [not_moved_error_str.letter], al
+		mov ax, bp
+		add ax, '1'
+		mov [not_moved_error_str.position], al
+		mov si, not_moved_error_str
+		jmp print_error
+
+		.moved:
+		.not_wrong_place:
+		inc bp
+		loop .wrong_places
+
 	.done:
 
 check_dictionary:
@@ -953,6 +998,7 @@ exact_hit_error_str:
 	db " must be '"
 	.letter db '#'
 	db "'$"
+
 wrong_place_error_str:
 	db " - letter '"
 	.letter db '#'
@@ -960,6 +1006,20 @@ wrong_place_error_str:
 	.position db '#'
 	db ' must be reused$'
 
+not_moved_error_str:
+	db " - letter '"
+	.letter db '#'
+	db "' in position "
+	.position db '#'
+	db ' must be moved$'
+
+ruled_out_error_str:
+	db " - letter '"
+	.letter db '#'
+	db "' in position "
+	.position db '#'
+	db ' has been ruled out$'
+
 section .rodata
 
 greeting_str db 'Welcome to hello DOSdl. Run `dosdl /?` for help.', 13, 10, '$'