Calculator: Add a "Custom" entry to the rounding menu

This entry pop a dialog to ask the user to enter a value. The Calculator
will automatically put itself in this mode if you enter a number with
more digits in the fractional part than the actual maximum length.

Userland/Applications/Calculator/CMakeLists.txt

@@ -9,6 +9,7 @@ set(SOURCES
     main.cpp
     Calculator.cpp
     CalculatorWidget.cpp
+    RoundingDialog.cpp
     Keypad.cpp
     CalculatorGML.h
 )

Userland/Applications/Calculator/CalculatorWidget.cpp

@@ -9,7 +9,6 @@
 
 #include "CalculatorWidget.h"
 #include <Applications/Calculator/CalculatorGML.h>
-#include <LibCore/Event.h>
 #include <LibCrypto/BigFraction/BigFraction.h>
 #include <LibGUI/Button.h>
 #include <LibGUI/Label.h>
@@ -160,8 +159,7 @@ void CalculatorWidget::keydown_event(GUI::KeyEvent& event)
         m_keypad.set_value(m_calculator.finish_operation(m_keypad.value()));
         mimic_pressed_button(m_equals_button);
     } else if (event.code_point() >= '0' && event.code_point() <= '9') {
-        u32 digit = event.code_point() - '0';
-        m_keypad.type_digit(digit);
+        auto const digit = m_keypad.type_digit(event.code_point() - '0');
         mimic_pressed_button(m_digit_button[digit]);
     } else if (event.code_point() == '.') {
         m_keypad.type_decimal_point();
@@ -219,8 +217,19 @@ void CalculatorWidget::keydown_event(GUI::KeyEvent& event)
     update_display();
 }
 
+unsigned CalculatorWidget::rounding_length() const
+{
+    return m_keypad.rounding_length();
+}
+
 void CalculatorWidget::set_rounding_length(unsigned rounding_threshold)
 {
     m_keypad.set_rounding_length(rounding_threshold);
     update_display();
 }
+
+void CalculatorWidget::set_rounding_custom(GUI::Action& action, StringView format)
+{
+    m_format = format;
+    m_rounding_custom = action;
+}

Userland/Applications/Calculator/CalculatorWidget.h

@@ -12,6 +12,7 @@
 #include "Keypad.h"
 #include <AK/Vector.h>
 #include <LibCrypto/BigFraction/BigFraction.h>
+#include <LibGUI/Action.h>
 #include <LibGUI/Widget.h>
 
 class CalculatorWidget final : public GUI::Widget {
@@ -21,8 +22,11 @@ public:
     String get_entry();
     void set_entry(Crypto::BigFraction);
 
+    unsigned rounding_length() const;
     void set_rounding_length(unsigned);
 
+    void set_rounding_custom(GUI::Action& action, StringView);
+
 private:
     CalculatorWidget();
     void add_operation_button(GUI::Button&, Calculator::Operation);
@@ -58,4 +62,7 @@ private:
     RefPtr<GUI::Button> m_inverse_button;
     RefPtr<GUI::Button> m_percent_button;
     RefPtr<GUI::Button> m_equals_button;
+
+    StringView m_format;
+    RefPtr<GUI::Action> m_rounding_custom;
 };

Userland/Applications/Calculator/Keypad.cpp

@@ -12,7 +12,7 @@
 #include <LibCrypto/BigInt/UnsignedBigInteger.h>
 #include <LibCrypto/NumberTheory/ModularFunctions.h>
 
-void Keypad::type_digit(int digit)
+unsigned Keypad::type_digit(int digit)
 {
     switch (m_state) {
     case State::External:
@@ -34,6 +34,7 @@ void Keypad::type_digit(int digit)
         m_frac_length.set_to(m_frac_length.plus(1));
         break;
     }
+    return m_frac_length.to_u64();
 }
 
 void Keypad::type_decimal_point()
@@ -139,3 +140,8 @@ void Keypad::set_rounding_length(unsigned rounding_threshold)
 {
     m_displayed_fraction_length = rounding_threshold;
 }
+
+unsigned Keypad::rounding_length() const
+{
+    return m_displayed_fraction_length;
+}

Userland/Applications/Calculator/Keypad.h

@@ -21,7 +21,7 @@ public:
     Keypad() = default;
     ~Keypad() = default;
 
-    void type_digit(int digit);
+    unsigned type_digit(int digit);
     void type_decimal_point();
     void type_backspace();
 
@@ -30,6 +30,7 @@ public:
     void set_to_0();
 
     void set_rounding_length(unsigned);
+    unsigned rounding_length() const;
 
     String to_string() const;
 

Userland/Applications/Calculator/RoundingDialog.cpp

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2022, Lucas Chollet <lucas.chollet@free.fr>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "RoundingDialog.h"
+#include <LibGUI/BoxLayout.h>
+#include <LibGUI/Button.h>
+#include <LibGUI/Label.h>
+#include <LibGUI/SpinBox.h>
+#include <LibGUI/TextEditor.h>
+
+RoundingDialog::ExecResult RoundingDialog::show(GUI::Window* parent_window, unsigned& rounding_value)
+{
+    auto dialog = RoundingDialog::construct(parent_window);
+
+    if (parent_window) {
+        dialog->set_icon(parent_window->icon());
+        dialog->center_within(*parent_window);
+    }
+
+    dialog->m_rounding_spinbox->set_value(rounding_value);
+
+    auto const result = dialog->exec();
+
+    if (result != GUI::Dialog::ExecResult::OK)
+        return result;
+
+    rounding_value = dialog->m_rounding_spinbox->value();
+
+    return GUI::Dialog::ExecResult::OK;
+}
+
+RoundingDialog::RoundingDialog(GUI::Window* parent_window)
+    : Dialog(parent_window)
+{
+    resize(m_dialog_length, m_dialog_height);
+    set_resizable(false);
+    set_title("Choose custom rounding");
+
+    auto& main_widget = set_main_widget<GUI::Widget>();
+
+    main_widget.set_fill_with_background_color(true);
+    main_widget.set_layout<GUI::VerticalBoxLayout>();
+
+    m_rounding_spinbox = GUI::SpinBox::construct();
+    m_buttons_container = GUI::Widget::construct();
+    m_ok_button = GUI::DialogButton::construct("OK");
+    m_cancel_button = GUI::DialogButton::construct("Cancel");
+
+    main_widget.add_child(*m_rounding_spinbox);
+    main_widget.add_child(*m_buttons_container);
+
+    m_buttons_container->set_layout<GUI::HorizontalBoxLayout>();
+    m_buttons_container->layout()->add_spacer();
+    m_buttons_container->add_child(*m_ok_button);
+    m_buttons_container->add_child(*m_cancel_button);
+
+    m_rounding_spinbox->on_return_pressed = [this] {
+        m_ok_button->click();
+    };
+
+    m_ok_button->on_click = [this](auto) {
+        done(ExecResult::OK);
+    };
+
+    m_cancel_button->on_click = [this](auto) {
+        done(ExecResult::Cancel);
+    };
+}

Userland/Applications/Calculator/RoundingDialog.h

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2022, Lucas Chollet <lucas.chollet@free.fr>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Vector.h>
+#include <LibGUI/Dialog.h>
+
+class RoundingDialog : public GUI::Dialog {
+    C_OBJECT(RoundingDialog);
+
+public:
+    static ExecResult show(GUI::Window* parent_window, unsigned& rounding_value);
+
+private:
+    RoundingDialog(GUI::Window* parent_window);
+    virtual ~RoundingDialog() override = default;
+
+    RefPtr<GUI::SpinBox> m_rounding_spinbox;
+    RefPtr<GUI::Widget> m_buttons_container;
+    RefPtr<GUI::DialogButton> m_ok_button;
+    RefPtr<GUI::DialogButton> m_cancel_button;
+
+    static constexpr unsigned m_dialog_length = 200;
+    static constexpr unsigned m_dialog_height = 54;
+};

Userland/Applications/Calculator/main.cpp

@@ -5,6 +5,7 @@
  */
 
 #include "CalculatorWidget.h"
+#include "RoundingDialog.h"
 #include <LibCore/System.h>
 #include <LibCrypto/NumberTheory/ModularFunctions.h>
 #include <LibGUI/Action.h>
@@ -51,7 +52,8 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
         auto clipboard = GUI::Clipboard::the().fetch_data_and_type();
         if (clipboard.mime_type == "text/plain") {
             if (!clipboard.data.is_empty()) {
-                widget->set_entry(Crypto::BigFraction(StringView(clipboard.data)));
+                auto const number = StringView(clipboard.data);
+                widget->set_entry(Crypto::BigFraction(number));
             }
         }
     }));
@@ -74,16 +76,37 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
 
     static constexpr auto rounding_modes = Array { 0, 2, 4 };
 
-    for (auto const rounding_mode : rounding_modes) {
-        auto round_action = GUI::Action::create_checkable(String::formatted("To &{} digits", rounding_mode), [&widget, rounding_mode](auto&) {
-            widget->set_rounding_length(rounding_mode);
-        });
+    Optional<unsigned> last_rounding_mode = 1;
+    for (unsigned i {}; i < rounding_modes.size(); ++i) {
+        auto round_action = GUI::Action::create_checkable(String::formatted("To &{} digits", rounding_modes[i]),
+            [&widget, rounding_mode = rounding_modes[i], &last_rounding_mode, i](auto&) {
+                widget->set_rounding_length(rounding_mode);
+                last_rounding_mode = i;
+            });
 
         preview_actions.add_action(*round_action);
         round_menu.add_action(*round_action);
     }
 
+    constexpr auto format { "&Custom - {} ..."sv };
+    auto round_custom = GUI::Action::create_checkable(String::formatted(format, 0), [&](auto& action) {
+        unsigned custom_rounding_length = widget->rounding_length();
+
+        if (RoundingDialog::show(window, custom_rounding_length) == GUI::Dialog::ExecResult::OK) {
+            action.set_text(String::formatted(format, custom_rounding_length));
+            widget->set_rounding_length(custom_rounding_length);
+            last_rounding_mode.clear();
+        } else if (last_rounding_mode.has_value())
+            round_menu.action_at(last_rounding_mode.value())->activate();
+    });
+
+    widget->set_rounding_custom(round_custom, format);
+
+    preview_actions.add_action(*round_custom);
     preview_actions.set_exclusive(true);
+    round_menu.add_action(*round_custom);
+
+    round_menu.action_at(last_rounding_mode.value())->activate();
 
     auto& help_menu = window->add_menu("&Help");
     help_menu.add_action(GUI::CommonActions::make_about_action("Calculator", app_icon, window));