ScreenManager.h

//#pragma once
#ifndef SCREEN_MANAGER_H
#define SCREEN_MANAGER_H
 
#include <stdint.h>
#include "ScreenRouter.h"
#include "ScreenEntry.h"
#include "ScreenTransition.h"
 
 
using ScreenId = uint8_t;
 
class ScreenManager {
 
public:
 
    ~ScreenManager();
 
    void begin();
 
    void update(uint32_t nowMs);
 
    bool registerScreen(ScreenId id, IManagedScreen* screen ) {
        if ( id == 0  || !screen ) return false;
        if ( haveScreen(id)) return false;
        auto* entry = new ScreenEntryExternal(screen, id);
        entry->instance = screen;
        addScreenEntry(entry);
        if ( begun ) screen->begin();
        return true;
    }
 
    template<typename T>
    bool registerScreen(ScreenId id) {
        if ( id == 0 ) return false;
        if ( haveScreen(id)) return false;
        auto* entry = new ScreenEntryManaged<T>(id);
        addScreenEntry(entry);
        return true;
    }
 
    void setFps(uint8_t fps) {
        if ( fps == 0 ) {
            displayRefreshMs = 0;
        } else {
            displayRefreshMs = (uint16_t)(1000/fps);
            displayRefreshMs = (displayRefreshMs < 4) ? 4 : displayRefreshMs; //Ensure getFps doesn't overflow
        }
    }
 
    uint8_t getFps() const {
        if ( displayRefreshMs == 0 ) return 0;
        return (uint8_t)(1000/displayRefreshMs);
    }
 
    bool isCurrent(const ScreenId id) const;
 
    bool isPrevious(const ScreenId id) const;
 
    IManagedScreen* getCurrent() const;
 
 
    ScreenId getPreviousId() const;
 
    bool haveScreen(const ScreenId id) const;
 
    void requestScreen(const ScreenId nextScreen);
 
    void requestScreen(const TransitionIntent& intent);
 
    void addRouter(ScreenRouter* router);
 
    bool setInitialScreen(const ScreenId id);
 
 
    private:    
    ScreenEntry* getScreenEntry(const ScreenId id) const;
 
 
 
    private:
 
    void addScreenEntry(ScreenEntry* entry);
 
 
 
    void resolveTransition(const TransitionIntent& intent);
 
 
    ScreenEntry* current = nullptr;
    ScreenEntry* previous = nullptr;
    //ScreenEntry* pausedScreen = nullptr;
    TransitionIntent pendingIntent = {};
    ScreenId initialScreenId = 0;
    bool begun = false;
 
 
    uint16_t displayRefreshMs = 100;
    uint32_t lastDisplayRefresh = 0;
 
 
 
    // List management
    ScreenEntry* firstScreenEntry = nullptr;
    ScreenEntry* lastScreenEntry = nullptr;
 
    ScreenRouter* firstRouter = nullptr;
    ScreenRouter* lastRouter = nullptr;
 
 
};
 
 
#endif