From 0d10729b37bb3b23a2a566d0ebac71f0cbc70bfa Mon Sep 17 00:00:00 2001
From: "David Vereb (Home)" <dvereb@dvereb.com>
Date: Wed, 3 Apr 2019 08:36:08 -0500
Subject: [PATCH] Allow user to change input style or clear input.

---
 Problem.cpp | 10 ++++++++--
 Problem.h   |  3 ++-
 main.cpp    | 15 +++++++++------
 3 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/Problem.cpp b/Problem.cpp
index cdb5428..f37ba51 100644
--- a/Problem.cpp
+++ b/Problem.cpp
@@ -33,7 +33,7 @@ Problem::~Problem()
 		delwin(win);
 }
 
-void Problem::Draw(bool selected)
+void Problem::Draw(bool selected, const INPUT_STYLE &input_style)
 {
 	if(!win)
 		return;
@@ -59,7 +59,13 @@ void Problem::Draw(bool selected)
 	};
 	mvwprintw(win, 4, 2, "========");
 	mvwprintw(win, 5, 4, "%'6d", Input());
-	mvwprintw(win, 5, 9, "");
+
+	// Place the cursor in the correct position!
+	int length = input.length() + ((input.length() - 1) / 3); // add commas, too!
+	if(input_style == INPUT_STYLE::INPUT_PREPEND)
+		mvwprintw(win, 5, 9 - length, "");
+	else
+		mvwprintw(win, 5, 10, "");
 	wrefresh(win);
 }
 
diff --git a/Problem.h b/Problem.h
index a458710..ff2e567 100644
--- a/Problem.h
+++ b/Problem.h
@@ -29,8 +29,9 @@ public:
 	Problem(PROBLEM_TYPE type, unsigned short max_digits, unsigned win_x, unsigned win_y);
 	~Problem();
 
-	void Draw(bool selected);
+	void Draw(bool selected, const INPUT_STYLE &input_style);
 	void Input(const INPUT_STYLE input_style, char character);
+	void ClearInput() { input = ""; }
 	bool Correct() const;
 
 private:
diff --git a/main.cpp b/main.cpp
index bf9f468..18393db 100644
--- a/main.cpp
+++ b/main.cpp
@@ -47,25 +47,28 @@ int main(int argc, char *argv[])
 		std::vector<Problem*> problems = GenerateProblems(addition, subtraction);
 		std::vector<Problem*>::iterator selected = problems.begin();
 
+		INPUT_STYLE input_style = INPUT_STYLE::INPUT_APPEND;
 		for(auto *problem : problems)
 			if(problem)
-				problem->Draw(problem == *selected);
+				problem->Draw(problem == *selected, input_style);
 
-		INPUT_STYLE input_style = INPUT_STYLE::INPUT_PREPEND;
 		while(selected != problems.end() && *selected)
 		{
 			Problem *current_problem = *selected;
-			current_problem->Draw(true); // refresh with new input
+			current_problem->Draw(true, input_style); // refresh with new input
 			auto input = getch();
 			if(input == 'q') // early exit
 				break;
 			switch(input)
 			{
 			case KEY_LEFT:
-				input_style = INPUT_STYLE::INPUT_APPEND;
+				input_style = INPUT_STYLE::INPUT_PREPEND;
 				break;
 			case KEY_RIGHT:
-				input_style = INPUT_STYLE::INPUT_PREPEND;
+				input_style = INPUT_STYLE::INPUT_APPEND;
+				break;
+			case KEY_BACKSPACE:
+				current_problem->ClearInput();
 				break;
 			case '0':
 			case '1':
@@ -78,12 +81,12 @@ int main(int argc, char *argv[])
 			case '8':
 			case '9':
 				current_problem->Input(input_style, input);
-				current_problem->Draw(true); // refresh with new input
 				break;
 			};
 
 			if(current_problem->Correct())
 				++selected;
+			current_problem->Draw(true, input_style); // refresh with new input
 		}
 
 		for(auto *problem : problems)