src/screen.h

   1 /***************************************************************************
   2  *   Copyright (C) 2008-2016 by Andrzej Rybczak                            *
   3  *   electricityispower@gmail.com                                          *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.              *
  19  ***************************************************************************/
  20
  21 #ifndef NCMPCPP_SCREEN_H
  22 #define NCMPCPP_SCREEN_H
  23
  24 #include "menu.h"
  25 #include "scrollpad.h"
  26 #include "screen_type.h"
  27
  28 void drawSeparator(int x);
  29 void genericMouseButtonPressed(NC::Window &w, MEVENT me);
  30 void scrollpadMouseButtonPressed(NC::Scrollpad &w, MEVENT me);
  31
  32 /// An interface for various instantiations of Screen template class. Since C++ doesn't like
  33 /// comparison of two different instantiations of the same template class we need the most
  34 /// basic class to be non-template to allow it.
  35 struct BaseScreen
  36 {
  37         BaseScreen() : hasToBeResized(false) { }
  38         virtual ~BaseScreen() { }
  39
  40         /// @see Screen::isActiveWindow()
  41         virtual bool isActiveWindow(const NC::Window &w_) const = 0;
  42
  43         /// @see Screen::activeWindow()
  44         virtual NC::Window *activeWindow() = 0;
  45         virtual const NC::Window *activeWindow() const = 0;
  46
  47         /// @see Screen::refresh()
  48         virtual void refresh() = 0;
  49
  50         /// @see Screen::refreshWindow()
  51         virtual void refreshWindow() = 0;
  52
  53         /// @see Screen::scroll()
  54         virtual void scroll(NC::Scroll where) = 0;
  55
  56         /// Method used for switching to screen
  57         virtual void switchTo() = 0;
  58
  59         /// Method that should resize screen
  60         /// if requested by hasToBeResized
  61         virtual void resize() = 0;
  62
  63         /// @return ncurses timeout parameter for the screen
  64         virtual int windowTimeout() = 0;
  65
  66         /// @return title of the screen
  67         virtual std::wstring title() = 0;
  68
  69         /// @return type of the screen
  70         virtual ScreenType type() = 0;
  71
  72         /// If the screen contantly has to update itself
  73         /// somehow, it should be called by this function.
  74         virtual void update() = 0;
  75
  76         /// @see Screen::mouseButtonPressed()
  77         virtual void mouseButtonPressed(MEVENT me) = 0;
  78
  79         /// @return true if screen can be locked. Note that returning
  80         /// false here doesn't neccesarily mean that screen is also not
  81         /// mergable (eg. lyrics screen is not lockable since that wouldn't
  82         /// make much sense, but it's perfectly fine to merge it).
  83         virtual bool isLockable() = 0;
  84
  85         /// @return true if screen is mergable, ie. can be "proper" subwindow
  86         /// if one of the screens is locked. Screens that somehow resemble popups
  87         /// will want to return false here.
  88         virtual bool isMergable() = 0;
  89
  90         /// Locks current screen.
  91         /// @return true if lock was successful, false otherwise. Note that
  92         /// if there is already locked screen, it'll not overwrite it.
  93         bool lock();
  94
  95         /// Should be set to true each time screen needs resize
  96         bool hasToBeResized;
  97
  98         /// Unlocks a screen, ie. hides merged window (if there is one set).
  99         static void unlock();
 100
 101         const static int defaultWindowTimeout = 500;
 102
 103 protected:
 104         /// Gets X offset and width of current screen to be used eg. in resize() function.
 105         /// @param adjust_locked_screen indicates whether this function should
 106         /// automatically adjust locked screen's dimensions (if there is one set)
 107         /// if current screen is going to be subwindow.
 108         void getWindowResizeParams(size_t &x_offset, size_t &width, bool adjust_locked_screen = true);
 109 };
 110
 111 void applyToVisibleWindows(std::function<void(BaseScreen *)> f);
 112 void updateInactiveScreen(BaseScreen *screen_to_be_set);
 113 bool isVisible(BaseScreen *screen);
 114
 115 /// Class that all screens should derive from. It provides basic interface
 116 /// for the screen to be working properly and assumes that we didn't forget
 117 /// about anything vital.
 118 ///
 119 template <typename WindowT> struct Screen : public BaseScreen
 120 {
 121         typedef WindowT WindowType;
 122         typedef typename std::add_lvalue_reference<
 123                 WindowType
 124         >::type WindowReference;
 125         typedef typename std::add_lvalue_reference<
 126                 typename std::add_const<WindowType>::type
 127         >::type ConstWindowReference;
 128
 129 private:
 130         template <bool IsPointer, typename Result, typename ConstResult>
 131         struct getObject {
 132                 static Result &apply(WindowReference w) { return w; }
 133                 static ConstResult &constApply(ConstWindowReference w) { return w; }
 134         };
 135         template <typename Result, typename ConstResult>
 136         struct getObject<true, Result, ConstResult> {
 137                 static Result &apply(WindowType w) { return *w; }
 138                 static ConstResult &constApply(const WindowType w) { return *w; }
 139         };
 140
 141         typedef getObject<
 142                 std::is_pointer<WindowT>::value,
 143                 typename std::remove_pointer<WindowT>::type,
 144                 typename std::add_const<
 145                         typename std::remove_pointer<WindowT>::type
 146                 >::type
 147         > Accessor;
 148
 149 public:
 150         Screen() { }
 151         Screen(WindowT w_) : w(w_) { }
 152
 153         virtual ~Screen() { }
 154
 155         virtual bool isActiveWindow(const NC::Window &w_) const override {
 156                 return &Accessor::constApply(w) == &w_;
 157         }
 158
 159         /// Since some screens contain more that one window
 160         /// it's useful to determine the one that is being
 161         /// active
 162         /// @return address to window object cast to void *
 163         virtual NC::Window *activeWindow() override {
 164                 return &Accessor::apply(w);
 165         }
 166         virtual const NC::Window *activeWindow() const override {
 167                 return &Accessor::constApply(w);
 168         }
 169
 170         /// Refreshes whole screen
 171         virtual void refresh() override {
 172                 Accessor::apply(w).display();
 173         }
 174
 175         /// Refreshes active window of the screen
 176         virtual void refreshWindow() override {
 177                 Accessor::apply(w).display();
 178         }
 179
 180         /// Scrolls the screen by given amount of lines and
 181         /// if fancy scrolling feature is disabled, enters the
 182         /// loop that holds main loop until user releases the key
 183         /// @param where indicates where one wants to scroll
 184         virtual void scroll(NC::Scroll where) override {
 185                 Accessor::apply(w).scroll(where);
 186         }
 187
 188         /// @return timeout parameter used for the screen (in ms)
 189         /// @default defaultWindowTimeout
 190         virtual int windowTimeout() override {
 191                 return defaultWindowTimeout;
 192         }
 193
 194         /// Invoked after there was one of mouse buttons pressed
 195         /// @param me struct that contains coords of where the click
 196         /// had its place and button actions
 197         virtual void mouseButtonPressed(MEVENT me) override {
 198                 genericMouseButtonPressed(Accessor::apply(w), me);
 199         }
 200
 201         /// @return currently active window
 202         WindowReference main() {
 203                 return w;
 204         }
 205         ConstWindowReference main() const {
 206                 return w;
 207         }
 208
 209 protected:
 210         /// Template parameter that should indicate the main type
 211         /// of window used by the screen. What is more, it should
 212         /// always be assigned to the currently active window (if
 213         /// acreen contains more that one)
 214         WindowT w;
 215 };
 216
 217 /// Specialization for Screen<Scrollpad>::mouseButtonPressed that should
 218 /// not scroll whole page, but rather a few lines (the number of them is
 219 /// defined in the config)
 220 template <> inline void Screen<NC::Scrollpad>::mouseButtonPressed(MEVENT me) {
 221         scrollpadMouseButtonPressed(w, me);
 222 }
 223
 224 #endif // NCMPCPP_SCREEN_H
 225