TextEditor: Implement replacement functionality

This patch adds a new replace widget that cooperates with the find
widget, the replace widget takes the input in the find textbox, searches
for occurences of that input, and replaces them with the input provied
in the replace textbox.

3 files changed, 131 insertions, 13 deletions

diff --git a/Applications/TextEditor/TextEditorWidget.cpp b/Applications/TextEditor/TextEditorWidget.cpp
index daa84fc649..b6fdabc7e2 100644
--- a/Applications/TextEditor/TextEditorWidget.cpp
+++ b/Applications/TextEditor/TextEditorWidget.cpp
@@ -41,15 +41,30 @@ TextEditorWidget::TextEditorWidget()
             update_title();
     };
 
-    m_find_widget = GWidget::construct(this);
+    m_find_replace_widget = GWidget::construct(this);
+    m_find_replace_widget->set_fill_with_background_color(true);
+    m_find_replace_widget->set_size_policy(SizePolicy::Fill, SizePolicy::Fixed);
+    m_find_replace_widget->set_preferred_size(0, 48);
+    m_find_replace_widget->set_layout(make<GBoxLayout>(Orientation::Vertical));
+    m_find_replace_widget->layout()->set_margins({ 2, 2, 2, 4 });
+    m_find_replace_widget->set_visible(false);
+
+    m_find_widget = GWidget::construct(m_find_replace_widget);
     m_find_widget->set_fill_with_background_color(true);
     m_find_widget->set_size_policy(SizePolicy::Fill, SizePolicy::Fixed);
     m_find_widget->set_preferred_size(0, 22);
     m_find_widget->set_layout(make<GBoxLayout>(Orientation::Horizontal));
-    m_find_widget->layout()->set_margins({ 2, 2, 2, 2 });
     m_find_widget->set_visible(false);
 
+    m_replace_widget = GWidget::construct(m_find_replace_widget);
+    m_replace_widget->set_fill_with_background_color(true);
+    m_replace_widget->set_size_policy(SizePolicy::Fill, SizePolicy::Fixed);
+    m_replace_widget->set_preferred_size(0, 22);
+    m_replace_widget->set_layout(make<GBoxLayout>(Orientation::Horizontal));
+    m_replace_widget->set_visible(false);
+
     m_find_textbox = GTextBox::construct(m_find_widget);
+    m_replace_textbox = GTextBox::construct(m_replace_widget);
 
     m_find_next_action = GAction::create("Find next", { Mod_Ctrl, Key_G }, [&](auto&) {
         auto needle = m_find_textbox->text();
@@ -69,6 +84,7 @@ TextEditorWidget::TextEditorWidget()
                 GMessageBox::InputType::OK, window());
         }
     });
+
     m_find_previous_action = GAction::create("Find previous", { Mod_Ctrl | Mod_Shift, Key_G }, [&](auto&) {
         auto needle = m_find_textbox->text();
         if (needle.is_empty()) {
@@ -94,14 +110,78 @@ TextEditorWidget::TextEditorWidget()
         }
     });
 
-    m_find_previous_button = GButton::construct("Previous", m_find_widget);
+    m_replace_next_action = GAction::create("Replace next", { Mod_Ctrl, Key_F1 }, [&](auto&) {
+        auto needle = m_find_textbox->text();
+        auto substitute = m_replace_textbox->text();
+
+        if (needle.is_empty())
+            return;
+
+        auto selection_start = m_editor->normalized_selection().start();
+        if (!selection_start.is_valid())
+            selection_start = m_editor->normalized_selection().start();
+
+        auto found_range = m_editor->document().find_next(needle, selection_start);
+
+        if (found_range.is_valid()) {
+            m_editor->set_selection(found_range);
+            m_editor->insert_at_cursor_or_replace_selection(substitute);
+        } else {
+            GMessageBox::show(
+                String::format("Not found: \"%s\"", needle.characters()),
+                "Not found",
+                GMessageBox::Type::Information,
+                GMessageBox::InputType::OK, window());
+        }
+    });
+
+    m_replace_previous_action = GAction::create("Replace previous", { Mod_Ctrl | Mod_Shift, Key_F1 }, [&](auto&) {
+        auto needle = m_find_textbox->text();
+        auto substitute = m_replace_textbox->text();
+        if (needle.is_empty())
+            return;
+
+        auto selection_start = m_editor->normalized_selection().start();
+        if (!selection_start.is_valid())
+            selection_start = m_editor->normalized_selection().start();
+
+        auto found_range = m_editor->document().find_previous(needle, selection_start);
+
+        if (found_range.is_valid()) {
+            m_editor->set_selection(found_range);
+            m_editor->insert_at_cursor_or_replace_selection(substitute);
+        } else {
+            GMessageBox::show(
+                String::format("Not found: \"%s\"", needle.characters()),
+                "Not found",
+                GMessageBox::Type::Information,
+                GMessageBox::InputType::OK, window());
+        }
+    });
+
+    m_replace_all_action = GAction::create("Replace all", { Mod_Ctrl, Key_F2 }, [&](auto&) {
+        auto needle = m_find_textbox->text();
+        auto substitute = m_replace_textbox->text();
+        if (needle.is_empty())
+            return;
+
+
+        auto found_range = m_editor->document().find_next(needle);
+        while(found_range.is_valid()) {
+                m_editor->set_selection(found_range);
+                m_editor->insert_at_cursor_or_replace_selection(substitute);
+                found_range = m_editor->document().find_next(needle);
+        }
+    });
+
+    m_find_previous_button = GButton::construct("Find Previous", m_find_widget);
     m_find_previous_button->set_size_policy(SizePolicy::Fixed, SizePolicy::Fill);
-    m_find_previous_button->set_preferred_size(64, 0);
+    m_find_previous_button->set_preferred_size(150, 0);
     m_find_previous_button->set_action(*m_find_previous_action);
 
-    m_find_next_button = GButton::construct("Next", m_find_widget);
+    m_find_next_button = GButton::construct("Find Next", m_find_widget);
     m_find_next_button->set_size_policy(SizePolicy::Fixed, SizePolicy::Fill);
-    m_find_next_button->set_preferred_size(64, 0);
+    m_find_next_button->set_preferred_size(150, 0);
     m_find_next_button->set_action(*m_find_next_action);
 
     m_find_textbox->on_return_pressed = [this] {
@@ -109,17 +189,43 @@ TextEditorWidget::TextEditorWidget()
     };
 
     m_find_textbox->on_escape_pressed = [this] {
-        m_find_widget->set_visible(false);
+        m_find_replace_widget->set_visible(false);
+        m_editor->set_focus(true);
+    };
+
+    m_replace_previous_button = GButton::construct("Replace Previous", m_replace_widget);
+    m_replace_previous_button->set_size_policy(SizePolicy::Fixed, SizePolicy::Fill);
+    m_replace_previous_button->set_preferred_size(100, 0);
+    m_replace_previous_button->set_action(*m_replace_previous_action);
+
+    m_replace_next_button = GButton::construct("Replace Next", m_replace_widget);
+    m_replace_next_button->set_size_policy(SizePolicy::Fixed, SizePolicy::Fill);
+    m_replace_next_button->set_preferred_size(100, 0);
+    m_replace_next_button->set_action(*m_replace_next_action);
+
+    m_replace_all_button = GButton::construct("Replace ALl", m_replace_widget);
+    m_replace_all_button->set_size_policy(SizePolicy::Fixed, SizePolicy::Fill);
+    m_replace_all_button->set_preferred_size(100, 0);
+    m_replace_all_button->set_action(*m_replace_all_action);
+
+    m_replace_textbox->on_return_pressed = [this] {
+        m_replace_next_button->click();
+    };
+
+    m_replace_textbox->on_escape_pressed = [this] {
+        m_find_replace_widget->set_visible(false);
         m_editor->set_focus(true);
     };
 
-    m_find_action = GAction::create("Find...", { Mod_Ctrl, Key_F }, load_png("/res/icons/16x16/find.png"), [this](auto&) {
+    m_find_replace_action = GAction::create("Find/Replace..", { Mod_Ctrl, Key_F }, load_png("/res/icons/16x16/find.png"), [this](auto&) {
+        m_find_replace_widget->set_visible(true);
         m_find_widget->set_visible(true);
+        m_replace_widget->set_visible(true);
         m_find_textbox->set_focus(true);
         m_find_textbox->select_all();
     });
 
-    m_editor->add_custom_context_menu_action(*m_find_action);
+    m_editor->add_custom_context_menu_action(*m_find_replace_action);
     m_editor->add_custom_context_menu_action(*m_find_next_action);
     m_editor->add_custom_context_menu_action(*m_find_previous_action);
 
@@ -223,9 +329,12 @@ TextEditorWidget::TextEditorWidget()
     edit_menu->add_action(m_editor->paste_action());
     edit_menu->add_action(m_editor->delete_action());
     edit_menu->add_separator();
-    edit_menu->add_action(*m_find_action);
+    edit_menu->add_action(*m_find_replace_action);
     edit_menu->add_action(*m_find_next_action);
     edit_menu->add_action(*m_find_previous_action);
+    edit_menu->add_action(*m_replace_next_action);
+    edit_menu->add_action(*m_replace_previous_action);
+    edit_menu->add_action(*m_replace_all_action);
     menubar->add_menu(move(edit_menu));
 
     auto font_menu = GMenu::construct("Font");
diff --git a/Applications/TextEditor/TextEditorWidget.h b/Applications/TextEditor/TextEditorWidget.h
index ac23c3bcbf..1389a18ff6 100644
--- a/Applications/TextEditor/TextEditorWidget.h
+++ b/Applications/TextEditor/TextEditorWidget.h
@@ -36,17 +36,26 @@ private:
     RefPtr<GAction> m_open_action;
     RefPtr<GAction> m_save_action;
     RefPtr<GAction> m_save_as_action;
-    RefPtr<GAction> m_find_action;
+    RefPtr<GAction> m_find_replace_action;
     RefPtr<GAction> m_line_wrapping_setting_action;
     RefPtr<GAction> m_find_next_action;
     RefPtr<GAction> m_find_previous_action;
+    RefPtr<GAction> m_replace_next_action;
+    RefPtr<GAction> m_replace_previous_action;
+    RefPtr<GAction> m_replace_all_action;
 
     RefPtr<GStatusBar> m_statusbar;
 
     RefPtr<GTextBox> m_find_textbox;
+    RefPtr<GTextBox> m_replace_textbox;
     GButton* m_find_previous_button { nullptr };
     GButton* m_find_next_button { nullptr };
+    GButton* m_replace_previous_button { nullptr };
+    GButton* m_replace_next_button { nullptr };
+    GButton* m_replace_all_button { nullptr };
+    RefPtr<GWidget> m_find_replace_widget;
     RefPtr<GWidget> m_find_widget;
+    RefPtr<GWidget> m_replace_widget;
 
     bool m_document_dirty { false };
     bool m_document_opening { false };
diff --git a/Libraries/LibGUI/GTextEditor.h b/Libraries/LibGUI/GTextEditor.h
index 65219d1fc8..a5bc1f537e 100644
--- a/Libraries/LibGUI/GTextEditor.h
+++ b/Libraries/LibGUI/GTextEditor.h
@@ -64,8 +64,9 @@ public:
     // FIXME: This should take glyph spacing into account, no?
     int glyph_width() const { return font().glyph_width('x'); }
 
-    bool write_to_file(const StringView& path);
 
+    void insert_at_cursor_or_replace_selection(const StringView&);
+    bool write_to_file(const StringView& path);
     bool has_selection() const { return m_selection.is_valid(); }
     String selected_text() const;
     void set_selection(const GTextRange&);
@@ -156,7 +157,6 @@ private:
     int ruler_width() const;
     Rect ruler_content_rect(size_t line) const;
     void toggle_selection_if_needed_for_event(const GKeyEvent&);
-    void insert_at_cursor_or_replace_selection(const StringView&);
     void delete_selection();
     void did_update_selection();
     int content_x_for_position(const GTextPosition&) const;