ladybird/Userland/Applications/Calculator/Calculator.cpp
2021-01-12 12:05:23 +01:00

144 lines
3.8 KiB
C++

/*
* Copyright (c) 2019-2020, Sergey Bugaev <bugaevc@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "Calculator.h"
#include <AK/Assertions.h>
#include <math.h>
Calculator::Calculator()
{
}
Calculator::~Calculator()
{
}
double Calculator::begin_operation(Operation operation, double argument)
{
double res = 0.0;
switch (operation) {
case Operation::None:
ASSERT_NOT_REACHED();
case Operation::Add:
case Operation::Subtract:
case Operation::Multiply:
case Operation::Divide:
m_saved_argument = argument;
m_operation_in_progress = operation;
return argument;
case Operation::Sqrt:
if (argument < 0.0) {
m_has_error = true;
return argument;
}
res = sqrt(argument);
clear_operation();
break;
case Operation::Inverse:
if (argument == 0.0) {
m_has_error = true;
return argument;
}
res = 1 / argument;
clear_operation();
break;
case Operation::Percent:
res = argument * 0.01;
break;
case Operation::ToggleSign:
res = -argument;
break;
case Operation::MemClear:
m_mem = 0.0;
res = argument;
break;
case Operation::MemRecall:
res = m_mem;
break;
case Operation::MemSave:
m_mem = argument;
res = argument;
break;
case Operation::MemAdd:
m_mem += argument;
res = m_mem;
break;
}
return res;
}
double Calculator::finish_operation(double argument)
{
double res = 0.0;
switch (m_operation_in_progress) {
case Operation::None:
return argument;
case Operation::Add:
res = m_saved_argument + argument;
break;
case Operation::Subtract:
res = m_saved_argument - argument;
break;
case Operation::Multiply:
res = m_saved_argument * argument;
break;
case Operation::Divide:
if (argument == 0.0) {
m_has_error = true;
return argument;
}
res = m_saved_argument / argument;
break;
case Operation::Sqrt:
case Operation::Inverse:
case Operation::Percent:
case Operation::ToggleSign:
case Operation::MemClear:
case Operation::MemRecall:
case Operation::MemSave:
case Operation::MemAdd:
ASSERT_NOT_REACHED();
}
clear_operation();
return res;
}
void Calculator::clear_operation()
{
m_operation_in_progress = Operation::None;
m_saved_argument = 0.0;
clear_error();
}