Display error messages in top-line overlay.

terminaloverlay.hpp

@@ -0,0 +1,107 @@
+#ifndef TERMINAL_OVERLAY_HPP
+#define TERMINAL_OVERLAY_HPP
+
+#include "terminalframebuffer.hpp"
+#include "network.hpp"
+
+#include <list>
+
+namespace Overlay {
+  using namespace Terminal;
+  using namespace Network;
+  using namespace std;
+
+  enum Validity {
+    Pending,
+    Correct,
+    IncorrectOrExpired
+  };
+
+  /* The individual elements of an overlay -- cursor movements and replaced cells */
+  class OverlayElement {
+  public:
+    uint64_t expiration_time;
+
+    virtual void apply( Framebuffer &fb ) const = 0;
+    virtual Validity get_validity( const Framebuffer & ) const;
+
+    OverlayElement( uint64_t s_expiration_time ) : expiration_time( s_expiration_time ) {}
+    virtual ~OverlayElement() {}
+  };
+
+  class OverlayCell : public OverlayElement {
+  public:
+    int row, col;
+    Cell replacement;
+
+    OverlayCell( uint64_t expiration_time, int s_row, int s_col, int background_color );
+    void apply( Framebuffer &fb ) const;
+  };
+
+  class ConditionalOverlayCell : public OverlayCell {
+  public:
+    Cell original_contents;
+
+    Validity get_validity( const Framebuffer &fb ) const;
+  };
+
+  class CursorMove : public OverlayElement {
+  public:
+    int new_row, new_col;
+
+    void apply( Framebuffer &fb ) const;
+  };
+
+  class ConditionalCursorMove : public CursorMove {
+  public:
+    Validity get_validity( const Framebuffer &fb ) const;
+  };
+
+  /* the various overlays -- some predictive and some for local notifications */
+  class OverlayEngine {
+  protected:
+    list<OverlayElement *> elements;
+
+  public:
+    void cull( const Framebuffer &fb );
+    virtual void apply( Framebuffer &fb ) const;
+    void clear( void );
+
+    OverlayEngine() : elements() {}
+    virtual ~OverlayEngine();
+  };
+
+  class NotificationEngine : public OverlayEngine {
+  private:
+    bool needs_render;
+
+    uint64_t last_word;
+    uint64_t last_render;
+
+    wstring message;
+    uint64_t message_expiration;
+
+  public:
+    void apply( Framebuffer &fb ) const;
+    void set_notification_string( const wstring s_message );
+    void server_ping( uint64_t s_last_word );
+    void render_notification( void );
+
+    NotificationEngine();
+  };
+
+  /* the overlay manager */
+  class OverlayManager {
+  private:
+    NotificationEngine notifications;
+
+  public:
+    void apply( Framebuffer &fb ) const;
+
+    NotificationEngine & get_notification_engine( void ) { return notifications; }
+
+    OverlayManager() : notifications() {} 
+  };
+}
+
+#endif