Ladybird: Expanded toolbar with browser history and home button

This patch takes the browser history code from the Serenity browser and
wires it up to the QT interface. This is tied in with a few extra
toolbar buttons associated with each tab.

7 files changed, 194 insertions, 9 deletions

diff --git a/Ladybird/CMakeLists.txt b/Ladybird/CMakeLists.txt
index ccc78718ff..ce3ccf8770 100644
--- a/Ladybird/CMakeLists.txt
+++ b/Ladybird/CMakeLists.txt
@@ -37,6 +37,7 @@ set(SOURCES
     RequestManagerQt.cpp
     main.cpp
     WebView.cpp
+    History.cpp
     Tab.cpp
 )
 
diff --git a/Ladybird/History.cpp b/Ladybird/History.cpp
new file mode 100644
index 0000000000..64e66633a9
--- /dev/null
+++ b/Ladybird/History.cpp
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "History.h"
+
+namespace Browser {
+
+void History::dump() const
+{
+    dbgln("Dump {} items(s)", m_items.size());
+    int i = 0;
+    for (auto& item : m_items) {
+        dbgln("[{}] {} '{}' {}", i, item.url, item.title, m_current == i ? '*' : ' ');
+        ++i;
+    }
+}
+
+void History::push(const URL& url, String const& title)
+{
+    if (!m_items.is_empty() && m_items[m_current].url == url)
+        return;
+    m_items.shrink(m_current + 1);
+    m_items.append(URLTitlePair {
+        .url = url,
+        .title = title,
+    });
+    m_current++;
+}
+
+History::URLTitlePair History::current() const
+{
+    if (m_current == -1)
+        return {};
+    return m_items[m_current];
+}
+
+void History::go_back(int steps)
+{
+    VERIFY(can_go_back(steps));
+    m_current -= steps;
+}
+
+void History::go_forward(int steps)
+{
+    VERIFY(can_go_forward(steps));
+    m_current += steps;
+}
+
+void History::clear()
+{
+    m_items = {};
+    m_current = -1;
+}
+
+void History::update_title(String const& title)
+{
+    m_items[m_current].title = title;
+}
+
+Vector<StringView> History::get_back_title_history()
+{
+    Vector<StringView> back_title_history;
+    for (int i = m_current - 1; i >= 0; i--) {
+        back_title_history.append(m_items[i].title);
+    }
+    return back_title_history;
+}
+
+Vector<StringView> History::get_forward_title_history()
+{
+    Vector<StringView> forward_title_history;
+    for (int i = m_current + 1; i < static_cast<int>(m_items.size()); i++) {
+        forward_title_history.append(m_items[i].title);
+    }
+    return forward_title_history;
+}
+
+}
diff --git a/Ladybird/History.h b/Ladybird/History.h
new file mode 100644
index 0000000000..4449944c72
--- /dev/null
+++ b/Ladybird/History.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/URL.h>
+#include <AK/Vector.h>
+
+namespace Browser {
+
+class History {
+public:
+    struct URLTitlePair {
+        URL url;
+        String title;
+    };
+    void dump() const;
+
+    void push(const URL& url, String const& title);
+    void update_title(String const& title);
+    URLTitlePair current() const;
+
+    Vector<StringView> get_back_title_history();
+    Vector<StringView> get_forward_title_history();
+
+    void go_back(int steps = 1);
+    void go_forward(int steps = 1);
+
+    bool can_go_back(int steps = 1) { return (m_current - steps) >= 0; }
+    bool can_go_forward(int steps = 1) { return (m_current + steps) < static_cast<int>(m_items.size()); }
+    void clear();
+
+private:
+    Vector<URLTitlePair> m_items;
+    int m_current { -1 };
+};
+
+}
diff --git a/Ladybird/Tab.cpp b/Ladybird/Tab.cpp
index 906e059173..75f823894c 100644
--- a/Ladybird/Tab.cpp
+++ b/Ladybird/Tab.cpp
@@ -7,9 +7,9 @@
 
 #include "Tab.h"
 #include "BrowserWindow.h"
+#include "History.h"
 #include <QCoreApplication>
 #include <QStatusBar>
-#include <utility>
 
 extern String s_serenity_resource_root;
 
@@ -26,21 +26,67 @@ Tab::Tab(QMainWindow* window)
     m_layout->addWidget(m_toolbar);
     m_layout->addWidget(m_view);
 
+    auto back_icon_path = QString("%1/res/icons/16x16/go-back.png").arg(s_serenity_resource_root.characters());
+    auto forward_icon_path = QString("%1/res/icons/16x16/go-forward.png").arg(s_serenity_resource_root.characters());
+    auto home_icon_path = QString("%1/res/icons/16x16/go-home.png").arg(s_serenity_resource_root.characters());
     auto reload_icon_path = QString("%1/res/icons/16x16/reload.png").arg(s_serenity_resource_root.characters());
-    auto* reload_action = new QAction(QIcon(reload_icon_path), "Reload");
-    reload_action->setShortcut(QKeySequence("Ctrl+R"));
-    m_toolbar->addAction(reload_action);
+    m_back_action = make<QAction>(QIcon(back_icon_path), "Back");
+    m_back_action->setShortcut(QKeySequence("Alt+Left"));
+    m_forward_action = make<QAction>(QIcon(forward_icon_path), "Forward");
+    m_forward_action->setShortcut(QKeySequence("Alt+Right"));
+    m_home_action = make<QAction>(QIcon(home_icon_path), "Home");
+    m_reload_action = make<QAction>(QIcon(reload_icon_path), "Reload");
+    m_reload_action->setShortcut(QKeySequence("Ctrl+R"));
+
+    m_toolbar->addAction(m_back_action);
+    m_toolbar->addAction(m_forward_action);
+    m_toolbar->addAction(m_reload_action);
+    m_toolbar->addAction(m_home_action);
     m_toolbar->addWidget(m_location_edit);
 
     QObject::connect(m_view, &WebView::linkHovered, m_window->statusBar(), &QStatusBar::showMessage);
     QObject::connect(m_view, &WebView::linkUnhovered, m_window->statusBar(), &QStatusBar::clearMessage);
 
-    QObject::connect(m_view, &WebView::loadStarted, m_location_edit, &QLineEdit::setText);
+    QObject::connect(m_view, &WebView::loadStarted, [this](const URL& url) {
+        m_location_edit->setText(url.to_string().characters());
+        m_history.push(url, m_title.toUtf8().data());
+    });
     QObject::connect(m_location_edit, &QLineEdit::returnPressed, this, &Tab::location_edit_return_pressed);
     QObject::connect(m_view, &WebView::title_changed, this, &Tab::page_title_changed);
     QObject::connect(m_view, &WebView::favicon_changed, this, &Tab::page_favicon_changed);
 
-    QObject::connect(reload_action, &QAction::triggered, this, &Tab::reload);
+    QObject::connect(m_back_action, &QAction::triggered, this, &Tab::back);
+    QObject::connect(m_forward_action, &QAction::triggered, this, &Tab::forward);
+    QObject::connect(m_home_action, &QAction::triggered, this, &Tab::home);
+    QObject::connect(m_reload_action, &QAction::triggered, this, &Tab::reload);
+}
+
+void Tab::navigate(QString const& url)
+{
+    view().load(url.toUtf8().data());
+}
+
+void Tab::back()
+{
+    if (!m_history.can_go_back())
+        return;
+
+    m_history.go_back();
+    view().load(m_history.current().url.to_string());
+}
+
+void Tab::forward()
+{
+    if (!m_history.can_go_forward())
+        return;
+
+    m_history.go_forward();
+    view().load(m_history.current().url.to_string());
+}
+
+void Tab::home()
+{
+    navigate("https://www.serenityos.org/");
 }
 
 void Tab::reload()
@@ -50,11 +96,12 @@ void Tab::reload()
 
 void Tab::location_edit_return_pressed()
 {
-    view().load(m_location_edit->text().toUtf8().data());
+    navigate(m_location_edit->text());
 }
 
 void Tab::page_title_changed(QString title)
 {
+    m_title = title;
     emit title_changed(tab_index(), std::move(title));
 }
 
diff --git a/Ladybird/Tab.h b/Ladybird/Tab.h
index 9e01c9e4c0..511715232d 100644
--- a/Ladybird/Tab.h
+++ b/Ladybird/Tab.h
@@ -7,6 +7,9 @@
 
 #pragma once
 
+#define AK_DONT_REPLACE_STD
+
+#include "History.h"
 #include "WebView.h"
 #include <QBoxLayout>
 #include <QLineEdit>
@@ -20,10 +23,15 @@ public:
 
     WebView& view() { return *m_view; }
 
+    void navigate(QString const&);
+
 public slots:
     void location_edit_return_pressed();
     void page_title_changed(QString);
     void page_favicon_changed(QIcon);
+    void back();
+    void forward();
+    void home();
     void reload();
 
 signals:
@@ -36,6 +44,13 @@ private:
     QLineEdit* m_location_edit { nullptr };
     WebView* m_view { nullptr };
     QMainWindow* m_window { nullptr };
+    Browser::History m_history;
+    QString m_title;
+
+    OwnPtr<QAction> m_back_action;
+    OwnPtr<QAction> m_forward_action;
+    OwnPtr<QAction> m_home_action;
+    OwnPtr<QAction> m_reload_action;
 
     int tab_index();
 };
diff --git a/Ladybird/WebView.cpp b/Ladybird/WebView.cpp
index 1a66cce55d..bd6ce779df 100644
--- a/Ladybird/WebView.cpp
+++ b/Ladybird/WebView.cpp
@@ -148,7 +148,7 @@ public:
 
     virtual void page_did_start_loading(AK::URL const& url) override
     {
-        emit m_view.loadStarted(url.to_string().characters());
+        emit m_view.loadStarted(url);
     }
 
     virtual void page_did_finish_loading(AK::URL const&) override
diff --git a/Ladybird/WebView.h b/Ladybird/WebView.h
index a38e7e165f..c4a542cdb2 100644
--- a/Ladybird/WebView.h
+++ b/Ladybird/WebView.h
@@ -33,7 +33,7 @@ public:
 signals:
     void linkHovered(QString, int timeout = 0);
     void linkUnhovered();
-    void loadStarted(QString);
+    void loadStarted(const URL&);
     void title_changed(QString);
     void favicon_changed(QIcon);