UserInterface: status line messages are now DisplayLines

This add color support for the status line

13 files changed, 120 insertions, 108 deletions

diff --git a/README.asciidoc b/README.asciidoc
index 99075ad6..b446bf7b 100644
--- a/README.asciidoc
+++ b/README.asciidoc
@@ -407,7 +407,10 @@ there are some builtins color aliases:
  * +LineNumbers+: colors used by the number_lines highlighter
  * +MenuForeground+: colors for the selected element in menus
  * +MenuBackground+: colors for the not selected elements in menus
- * +Information+: colors the informations windows
+ * +Information+: colors the informations windows and information messages
+ * +Error+: colors of error messages
+ * +StatusLine+: colors used for the status line
+ * +StatusCursor+: colors used for the status line cursor
 
 Shell expansion
 ---------------
diff --git a/src/client_manager.cc b/src/client_manager.cc
index a7919cf1..fc95c118 100644
--- a/src/client_manager.cc
+++ b/src/client_manager.cc
@@ -4,6 +4,7 @@
 #include "buffer_manager.hh"
 #include "command_manager.hh"
 #include "file.hh"
+#include "color_registry.hh"
 
 namespace Kakoune
 {
@@ -64,7 +65,7 @@ void ClientManager::create_client(std::unique_ptr<UserInterface>&& ui,
     }
     catch (Kakoune::runtime_error& error)
     {
-        context->print_status(error.description());
+        context->print_status({ error.description(), get_color("Error") });
         context->hooks().run_hook("RuntimeError", error.description(), *context);
     }
     catch (Kakoune::client_removed&)
@@ -81,7 +82,7 @@ void ClientManager::create_client(std::unique_ptr<UserInterface>&& ui,
         }
         catch (Kakoune::runtime_error& error)
         {
-            context->print_status(error.description());
+            context->print_status({ error.description(), get_color("Error") });
             context->hooks().run_hook("RuntimeError", error.description(), *context);
         }
         catch (Kakoune::client_removed&)
@@ -191,7 +192,7 @@ Context& ClientManager::get_client_context(const String& name)
     throw runtime_error("no client named: " + name);
 }
 
-static String generate_status_line(const Context& context)
+static DisplayLine generate_status_line(const Context& context)
 {
     BufferCoord cursor = context.editor().main_selection().last().coord();
     std::ostringstream oss;
@@ -207,7 +208,7 @@ static String generate_status_line(const Context& context)
     oss << " [" << context.editor().selections().size() << " sel]";
     if (context.editor().is_editing())
         oss << " [insert]";
-    return oss.str();
+    return { oss.str(), get_color("StatusLine") };
 }
 
 void ClientManager::redraw_clients() const
diff --git a/src/color_registry.cc b/src/color_registry.cc
index c7684691..b30afb28 100644
--- a/src/color_registry.cc
+++ b/src/color_registry.cc
@@ -49,6 +49,9 @@ ColorRegistry::ColorRegistry()
         { "MenuForeground", { Color::Blue, Color::Cyan } },
         { "MenuBackground", { Color::Cyan, Color::Blue } },
         { "Information", { Color::Black, Color::Yellow } },
+        { "Error", { Color::Black, Color::Red } },
+        { "StatusLine", { Color::Cyan, Color::Default } },
+        { "StatusCursor", { Color::Black, Color::Cyan } },
       }
 {}
 
diff --git a/src/commands.cc b/src/commands.cc
index 819cebb7..706a4dfd 100644
--- a/src/commands.cc
+++ b/src/commands.cc
@@ -37,7 +37,7 @@ Buffer* open_or_create(const String& filename, Context& context)
     Buffer* buffer = create_buffer_from_file(filename);
     if (not buffer)
     {
-        context.print_status("new file " + filename);
+        context.print_status({ "new file " + filename, get_color("StatusLine") });
         buffer = new Buffer(filename, Buffer::Flags::File | Buffer::Flags::New);
     }
     return buffer;
@@ -424,7 +424,7 @@ void echo_message(const CommandParameters& params, Context& context)
     String message;
     for (auto& param : params)
         message += param + " ";
-    context.print_status(message);
+    context.print_status({ std::move(message), get_color("StatusLine") } );
 }
 
 void exec_commands_in_file(const CommandParameters& params,
@@ -803,8 +803,8 @@ public:
     }
     bool is_key_available() override { return m_pos < m_keys.size(); }
 
-    void print_status(const String& , CharCount) override {}
-    void draw(const DisplayBuffer&, const String&) override {}
+    void print_status(const DisplayLine&) override {}
+    void draw(const DisplayBuffer&, const DisplayLine&) override {}
     void menu_show(const memoryview<String>&,
                    DisplayCoord, ColorPair, ColorPair, MenuStyle) override {}
     void menu_select(int) override {}
diff --git a/src/context.hh b/src/context.hh
index bfbc6c6d..c6c7abc2 100644
--- a/src/context.hh
+++ b/src/context.hh
@@ -95,7 +95,7 @@ struct Context
         return GlobalHooks::instance();
     }
 
-    void print_status(const String& status) const
+    void print_status(const DisplayLine& status) const
     {
         if (has_ui())
             ui().print_status(status);
diff --git a/src/display_buffer.cc b/src/display_buffer.cc
index d9ab9609..f518ab50 100644
--- a/src/display_buffer.cc
+++ b/src/display_buffer.cc
@@ -42,6 +42,14 @@ void DisplayLine::optimize()
     }
 }
 
+CharCount DisplayLine::length() const
+{
+    CharCount len = 0;
+    for (auto& atom : m_atoms)
+        len += atom.content.length();
+    return len;
+}
+
 void DisplayBuffer::compute_range()
 {
     m_range.first  = BufferIterator();
diff --git a/src/display_buffer.hh b/src/display_buffer.hh
index 3879a31e..49bf67cb 100644
--- a/src/display_buffer.hh
+++ b/src/display_buffer.hh
@@ -112,12 +112,13 @@ struct DisplayAtom
 {
     ColorPair      colors;
     Attribute      attribute;
-
     AtomContent    content;
 
-    DisplayAtom(AtomContent content)
-        : content{std::move(content)}, attribute{Normal},
-          colors{Color::Default, Color::Default} {}
+    DisplayAtom(AtomContent content,
+                ColorPair colors = {Color::Default, Color::Default},
+                Attribute attribute = Normal)
+        : content{std::move(content)}, colors{colors}, attribute{attribute}
+    {}
 };
 
 class DisplayLine
@@ -130,6 +131,8 @@ public:
     explicit DisplayLine(LineCount buffer_line) : m_buffer_line(buffer_line) {}
     DisplayLine(LineCount buffer_line, AtomList atoms)
         : m_buffer_line(buffer_line), m_atoms(std::move(atoms)) {}
+    DisplayLine(String str, ColorPair color)
+        : m_buffer_line(-1), m_atoms{ { std::move(str), color } } {}
 
     LineCount buffer_line() const { return m_buffer_line; }
 
@@ -141,6 +144,8 @@ public:
 
     const AtomList& atoms() const { return m_atoms; }
 
+    CharCount length() const;
+
     // Split atom pointed by it at pos, returns an iterator to the first atom
     iterator split(iterator it, BufferIterator pos);
 
diff --git a/src/input_handler.cc b/src/input_handler.cc
index f8a2fc64..cb9cabbf 100644
--- a/src/input_handler.cc
+++ b/src/input_handler.cc
@@ -144,6 +144,18 @@ private:
     String         m_line;
 };
 
+static DisplayLine line_with_cursor(const String& str, CharCount cursor_pos)
+{
+    assert(cursor_pos <= str.char_length());
+    if (cursor_pos == str.char_length())
+        return DisplayLine{-1, { {str, get_color("StatusLine")},
+                                 {" "_str, get_color("StatusCursor")} }};
+    else
+        return DisplayLine(-1, { DisplayAtom{ str.substr(0, cursor_pos), get_color("StatusLine") },
+                                  DisplayAtom{ str.substr(cursor_pos, 1), get_color("StatusCursor") },
+                                  DisplayAtom{ str.substr(cursor_pos+1), get_color("StatusLine") } });
+}
+
 class Menu : public InputMode
 {
 public:
@@ -167,7 +179,7 @@ public:
         if (key == Key(Key::Modifiers::Control, 'm'))
         {
             context().ui().menu_hide();
-            context().ui().print_status("");
+            context().ui().print_status(DisplayLine{ -1 });
             reset_normal_mode();
             int selected = m_selected - m_choices.begin();
             m_callback(selected, MenuEvent::Validate, context());
@@ -180,7 +192,7 @@ public:
                 m_edit_filter = false;
                 m_filter = boost::regex(".*");
                 m_filter_editor.reset("");
-                context().ui().print_status("");
+                context().ui().print_status(DisplayLine{ -1 });
             }
             else
             {
@@ -228,8 +240,8 @@ public:
         }
 
         if (m_edit_filter)
-            context().ui().print_status("/" + m_filter_editor.line(),
-                                      m_filter_editor.cursor_pos() + 1);
+            context().ui().print_status(line_with_cursor("/" + m_filter_editor.line(),
+                                                         m_filter_editor.cursor_pos() + 1));
    }
 
 private:
@@ -279,7 +291,7 @@ public:
           m_completer(completer), m_callback(callback)
     {
         m_history_it = ms_history[m_prompt].end();
-        context().ui().print_status(m_prompt, m_prompt.char_length());
+        context().ui().print_status(line_with_cursor(m_prompt, m_prompt.char_length()));
     }
 
     void on_key(const Key& key) override
@@ -302,7 +314,7 @@ public:
                     history.erase(it);
                 history.push_back(line);
             }
-            context().ui().print_status("");
+            context().ui().print_status(DisplayLine{ -1 });
             context().ui().menu_hide();
             reset_normal_mode();
             // call callback after reset_normal_mode so that callback
@@ -312,7 +324,7 @@ public:
         }
         else if (key == Key::Escape or key == Key { Key::Modifiers::Control, 'c' })
         {
-            context().ui().print_status("");
+            context().ui().print_status(DisplayLine{ -1 });
             context().ui().menu_hide();
             reset_normal_mode();
             m_callback(line, PromptEvent::Abort, context());
@@ -417,8 +429,8 @@ public:
             m_current_completion = -1;
             m_line_editor.handle_key(key);
         }
-        context().ui().print_status(m_prompt + line,
-                                  m_prompt.char_length() + m_line_editor.cursor_pos());
+        auto curpos = m_prompt.char_length() + m_line_editor.cursor_pos();
+        context().ui().print_status(line_with_cursor(m_prompt + line, curpos));
         m_callback(line, PromptEvent::Change, context());
     }
 
diff --git a/src/main.cc b/src/main.cc
index bb63be0e..932fad61 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -223,7 +223,7 @@ void do_search_next(Context& context)
         } while (--count > 0);
     }
     else
-        context.print_status("no search pattern");
+        context.print_status({ "no search pattern", get_color("Error") });
 }
 
 template<bool smart>
@@ -255,7 +255,7 @@ void use_selection_as_search_pattern(Context& context)
 void do_yank(Context& context)
 {
     RegisterManager::instance()['"'] = context.editor().selections_content();
-    context.print_status("yanked " + int_to_str(context.editor().selections().size()) + " selections");
+    context.print_status({ "yanked " + int_to_str(context.editor().selections().size()) + " selections", get_color("Information") });
 }
 
 void do_cat_yank(Context& context)
@@ -265,8 +265,8 @@ void do_cat_yank(Context& context)
     for (auto& sel : sels)
         str += sel;
     RegisterManager::instance()['"'] = memoryview<String>(str);
-    context.print_status("concatenated and yanked " +
-                         int_to_str(sels.size()) + " selections");
+    context.print_status({ "concatenated and yanked " +
+                           int_to_str(sels.size()) + " selections", get_color("Information") });
 }
 
 void do_erase(Context& context)
@@ -716,8 +716,8 @@ std::unordered_map<Key, std::function<void (Context& context)>> keymap =
     { { Key::Modifiers::None, '*' }, use_selection_as_search_pattern<true> },
     { { Key::Modifiers::Alt,  '*' }, use_selection_as_search_pattern<false> },
 
-    { { Key::Modifiers::None, 'u' }, repeated([](Context& context) { if (not context.editor().undo()) { context.print_status("nothing left to undo"); } }) },
-    { { Key::Modifiers::None, 'U' }, repeated([](Context& context) { if (not context.editor().redo()) { context.print_status("nothing left to redo"); } }) },
+    { { Key::Modifiers::None, 'u' }, repeated([](Context& context) { if (not context.editor().undo()) { context.print_status({ "nothing left to undo", get_color("Information") }); } }) },
+    { { Key::Modifiers::None, 'U' }, repeated([](Context& context) { if (not context.editor().redo()) { context.print_status({ "nothing left to redo", get_color("Information") }); } }) },
 
     { { Key::Modifiers::Alt,  'i' }, do_select_object<SurroundFlags::ToBegin | SurroundFlags::ToEnd | SurroundFlags::Inner> },
     { { Key::Modifiers::Alt,  'a' }, do_select_object<SurroundFlags::ToBegin | SurroundFlags::ToEnd> },
diff --git a/src/ncurses.cc b/src/ncurses.cc
index 120b9876..1425c47c 100644
--- a/src/ncurses.cc
+++ b/src/ncurses.cc
@@ -86,7 +86,8 @@ void on_sigint(int)
 }
 
 NCursesUI::NCursesUI()
-    : m_stdin_watcher{0, [this](FDWatcher&){ if (m_input_callback) m_input_callback(); }}
+    : m_stdin_watcher{0, [this](FDWatcher&){ if (m_input_callback) m_input_callback(); }},
+      m_status_line{-1}
 {
     initscr();
     cbreak();
@@ -154,40 +155,44 @@ void NCursesUI::update_dimensions()
     --m_dimensions.line;
 }
 
+void NCursesUI::draw_line(const DisplayLine& line, CharCount col_index) const
+{
+    for (const DisplayAtom& atom : line)
+    {
+        set_attribute(A_UNDERLINE, atom.attribute & Underline);
+        set_attribute(A_REVERSE, atom.attribute & Reverse);
+        set_attribute(A_BLINK, atom.attribute & Blink);
+        set_attribute(A_BOLD, atom.attribute & Bold);
+
+        set_color(stdscr, atom.colors);
+
+        String content = atom.content.content();
+        if (content[content.length()-1] == '\n' and
+            content.char_length() - 1 < m_dimensions.column - col_index)
+        {
+            addutf8str(stdscr, Utf8Iterator(content.begin()), Utf8Iterator(content.end())-1);
+            addch(' ');
+        }
+        else
+        {
+            Utf8Iterator begin(content.begin()), end(content.end());
+            if (end - begin > m_dimensions.column - col_index)
+                end = begin + (m_dimensions.column - col_index);
+            addutf8str(stdscr, begin, end);
+            col_index += end - begin;
+        }
+    }
+}
+
 void NCursesUI::draw(const DisplayBuffer& display_buffer,
-                     const String& mode_line)
+                     const DisplayLine& mode_line)
 {
     LineCount line_index = 0;
     for (const DisplayLine& line : display_buffer.lines())
     {
         wmove(stdscr, (int)line_index, 0);
         wclrtoeol(stdscr);
-        CharCount col_index = 0;
-        for (const DisplayAtom& atom : line)
-        {
-            set_attribute(A_UNDERLINE, atom.attribute & Underline);
-            set_attribute(A_REVERSE, atom.attribute & Reverse);
-            set_attribute(A_BLINK, atom.attribute & Blink);
-            set_attribute(A_BOLD, atom.attribute & Bold);
-
-            set_color(stdscr, atom.colors);
-
-            String content = atom.content.content();
-            if (content[content.length()-1] == '\n' and
-                content.char_length() - 1 < m_dimensions.column - col_index)
-            {
-                addutf8str(stdscr, Utf8Iterator(content.begin()), Utf8Iterator(content.end())-1);
-                addch(' ');
-            }
-            else
-            {
-                Utf8Iterator begin(content.begin()), end(content.end());
-                if (end - begin > m_dimensions.column - col_index)
-                    end = begin + (m_dimensions.column - col_index);
-                addutf8str(stdscr, begin, end);
-                col_index += end - begin;
-            }
-        }
+            draw_line(line, 0);
         ++line_index;
     }
 
@@ -203,15 +208,16 @@ void NCursesUI::draw(const DisplayBuffer& display_buffer,
         addch('~');
     }
 
-    set_color(stdscr, { Color::Cyan, Color::Default });
-    draw_status();
-    CharCount status_len = mode_line.char_length();
+    move((int)m_dimensions.line, 0);
+    clrtoeol();
+    draw_line(m_status_line, 0);
+    CharCount status_len = mode_line.length();
     // only draw mode_line if it does not overlap one status line
-    if (m_dimensions.column - m_status_line.char_length() > status_len + 1)
+    if (m_dimensions.column - m_status_line.length() > status_len + 1)
     {
-        move((int)m_dimensions.line, (int)(m_dimensions.column - status_len));
-        addutf8str(stdscr, Utf8Iterator(mode_line.begin()),
-                   Utf8Iterator(mode_line.end()));
+        CharCount col = m_dimensions.column - status_len;
+        move((int)m_dimensions.line, (int)col);
+        draw_line(mode_line, col);
     }
     redraw();
 }
@@ -285,36 +291,12 @@ Key NCursesUI::get_key()
     return Key::Invalid;
 }
 
-void NCursesUI::draw_status()
+void NCursesUI::print_status(const DisplayLine& status)
 {
+    m_status_line   = status;
     move((int)m_dimensions.line, 0);
     clrtoeol();
-    if (m_status_cursor == -1)
-       addutf8str(stdscr, m_status_line.cbegin(), m_status_line.cend());
-    else
-    {
-        Utf8Iterator begin{m_status_line.begin()};
-        Utf8Iterator end{m_status_line.end()};
-        Utf8Iterator cursor_it{begin};
-        cursor_it.advance(m_status_cursor, end);
-
-        addutf8str(stdscr, m_status_line.cbegin(), cursor_it);
-        set_attribute(A_REVERSE, 1);
-        if (cursor_it == end)
-            addch(' ');
-        else
-            addutf8str(stdscr, cursor_it, cursor_it+1);
-        set_attribute(A_REVERSE, 0);
-        if (cursor_it != end)
-            addutf8str(stdscr, cursor_it+1, end);
-    }
-}
-
-void NCursesUI::print_status(const String& status, CharCount cursor_pos)
-{
-    m_status_line   = status;
-    m_status_cursor = cursor_pos;
-    draw_status();
+    draw_line(status, 0);
     redraw();
 }
 
diff --git a/src/ncurses.hh b/src/ncurses.hh
index 633ff110..de4f1dc6 100644
--- a/src/ncurses.hh
+++ b/src/ncurses.hh
@@ -20,8 +20,8 @@ public:
     NCursesUI& operator=(const NCursesUI&) = delete;
 
     void draw(const DisplayBuffer& display_buffer,
-              const String& mode_line) override;
-    void print_status(const String& status, CharCount cursor_pos) override;
+              const DisplayLine& mode_line) override;
+    void print_status(const DisplayLine& status) override;
 
     bool   is_key_available() override;
     Key    get_key() override;
@@ -42,13 +42,12 @@ public:
 private:
     friend void on_term_resize(int);
     void redraw();
+    void draw_line(const DisplayLine& line, CharCount col_index) const;
 
     DisplayCoord m_dimensions;
     void update_dimensions();
 
-    String    m_status_line;
-    CharCount m_status_cursor = -1;
-    void      draw_status();
+    DisplayLine m_status_line;
 
     WINDOW* m_menu_win = nullptr;
     std::vector<String> m_choices;
diff --git a/src/remote.cc b/src/remote.cc
index 8c14420e..01b6760b 100644
--- a/src/remote.cc
+++ b/src/remote.cc
@@ -186,7 +186,7 @@ public:
     RemoteUI(int socket);
     ~RemoteUI();
 
-    void print_status(const String& status, CharCount cursor_pos) override;
+    void print_status(const DisplayLine& status) override;
 
     void menu_show(const memoryview<String>& choices,
                    DisplayCoord anchor, ColorPair fg, ColorPair bg,
@@ -199,7 +199,7 @@ public:
     void info_hide() override;
 
     void draw(const DisplayBuffer& display_buffer,
-              const String& mode_line) override;
+              const DisplayLine& mode_line) override;
 
     bool is_key_available() override;
     Key  get_key() override;
@@ -226,12 +226,11 @@ RemoteUI::~RemoteUI()
     close(m_socket_watcher.fd());
 }
 
-void RemoteUI::print_status(const String& status, CharCount cursor_pos)
+void RemoteUI::print_status(const DisplayLine& status)
 {
     Message msg(m_socket_watcher.fd());
     msg.write(RemoteUIMsg::PrintStatus);
     msg.write(status);
-    msg.write(cursor_pos);
 }
 
 void RemoteUI::menu_show(const memoryview<String>& choices,
@@ -278,7 +277,7 @@ void RemoteUI::info_hide()
 }
 
 void RemoteUI::draw(const DisplayBuffer& display_buffer,
-                    const String& mode_line)
+                    const DisplayLine& mode_line)
 {
     Message msg(m_socket_watcher.fd());
     msg.write(RemoteUIMsg::Draw);
@@ -345,9 +344,8 @@ void RemoteClient::process_next_message()
     {
     case RemoteUIMsg::PrintStatus:
     {
-        auto status = read<String>(socket);
-        auto cursor_pos = read<CharCount>(socket);
-        m_ui->print_status(status, cursor_pos);
+        auto status = read<DisplayLine>(socket);
+        m_ui->print_status(status);
         break;
     }
     case RemoteUIMsg::MenuShow:
@@ -380,8 +378,8 @@ void RemoteClient::process_next_message()
         break;
     case RemoteUIMsg::Draw:
     {
-        DisplayBuffer display_buffer = read<DisplayBuffer>(socket);
-        String mode_line = read<String>(socket);
+        auto display_buffer = read<DisplayBuffer>(socket);
+        auto mode_line = read<DisplayLine>(socket);
         m_ui->draw(display_buffer, mode_line);
         break;
     }
diff --git a/src/user_interface.hh b/src/user_interface.hh
index 8fa99c4a..522357ab 100644
--- a/src/user_interface.hh
+++ b/src/user_interface.hh
@@ -12,6 +12,7 @@ namespace Kakoune
 
 class String;
 class DisplayBuffer;
+class DisplayLine;
 struct DisplayCoord;
 
 enum class MenuStyle
@@ -26,7 +27,7 @@ class UserInterface : public SafeCountable
 {
 public:
     virtual ~UserInterface() {}
-    virtual void print_status(const String& status, CharCount cursor_pos = -1) = 0;
+    virtual void print_status(const DisplayLine& status) = 0;
 
     virtual void menu_show(const memoryview<String>& choices,
                            DisplayCoord anchor, ColorPair fg, ColorPair bg,
@@ -39,7 +40,7 @@ public:
     virtual void info_hide() = 0;
 
     virtual void draw(const DisplayBuffer& display_buffer,
-                      const String& mode_line) = 0;
+                      const DisplayLine& mode_line) = 0;
     virtual DisplayCoord dimensions() = 0;
     virtual bool is_key_available() = 0;
     virtual Key  get_key() = 0;