AdventuresInLestoria/Adventures in Lestoria/ScrollableWindowComponent.h

#pragma region License
/*
License (OLC-3)
~~~~~~~~~~~~~~~

Copyright 2024 Joshua Sigona <sigonasr2@gmail.com>

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

1. Redistributions or derivations of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.

2. Redistributions or derivative works in binary form must reproduce the above
copyright notice. This list of conditions and the following	disclaimer must be
reproduced in the documentation and/or other materials provided with the distribution.

3. Neither the name of the copyright holder nor the names of its contributors may
be used to endorse or promote products derived from this software without specific
prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS	"AS IS" AND ANY
EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
SHALL THE COPYRIGHT	HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL,	SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT	(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.

Portions of this software are copyright © 2023 The FreeType
Project (www.freetype.org). Please see LICENSE_FT.txt for more information.
All rights reserved.
*/
#pragma endregion
#pragma once
#include "Menu.h"
#include "MenuComponent.h"
#include "MenuItemButton.h"
#include "AdventuresInLestoria.h"

using A=Attribute;

class ScrollableWindowComponent:public MenuComponent{
    friend class Menu;
protected:
    ViewPort subWindow;
    std::vector<std::weak_ptr<MenuComponent>>components;
    std::weak_ptr<MenuComponent>upButton;
    std::weak_ptr<MenuComponent>downButton;
    geom2d::rect<float>bounds; //It's for the scrollbar.
    float scrollBarHeight=0;
    float scrollBarTop=0;
    bool scrollBarSelected=false;
    float scrollBarHoverTime=0;
    vf2d scrollOffset{};
    vf2d targetScrollOffset{};
    float lastScrollUpdate=0.f;
    float selectionIndex=0.f;
protected:
    inline bool OnScreen(std::weak_ptr<MenuComponent>component){
        return geom2d::overlaps(geom2d::rect<float>{{},rect.size},geom2d::rect<float>{component.lock()->rect.pos+vf2d{2,2},component.lock()->rect.size-vf2d{2,2}});
    }
public:
    inline ScrollableWindowComponent(geom2d::rect<float>rect,ComponentAttr attributes=ComponentAttr::BACKGROUND|ComponentAttr::OUTLINE)
        :MenuComponent(rect,"",[](MenuFuncData data){return true;},ButtonAttr::UNSELECTABLE|ButtonAttr::UNSELECTABLE_VIA_KEYBOARD){
        background=attributes&ComponentAttr::BACKGROUND;
        border=attributes&ComponentAttr::OUTLINE;
    }
    virtual inline void RemoveAllComponents(){
        while(components.size()>0){
            RemoveButton(components.back());
        }
    }
    virtual inline void RemoveButton(std::weak_ptr<MenuComponent>button){
        auto componentSearchResults=std::find_if(components.begin(),components.end(),[&](std::weak_ptr<MenuComponent>ptr){return &*ptr.lock()==&*button.lock();});
        if(componentSearchResults==components.end())ERR("Could not find Component"<<std::quoted(button.lock()->GetName())<<" inside the component list!");
        components.erase(componentSearchResults);
        size_t removedCount=0;

        MenuType parentMenu=button.lock()->parentMenu;

        removedCount+=Menu::menus[parentMenu]->components.erase(button.lock()->GetName());
        if(removedCount!=1){
            std::cout<<"WARNING! Attempted to remove buttons from button listing, but not found!";
        }
        Menu::menus[parentMenu]->RecalculateComponentCount();
        CalculateBounds();
    }
    virtual inline void SetScrollAmount(vf2d scrollOffset){
        this->targetScrollOffset=scrollOffset;
    }
    //Provide an amount to scroll by in units/sec.
    virtual inline void Scroll(float amt){
		SetScrollAmount(GetTargetScrollAmount()-vf2d{0,amt*game->GetElapsedTime()*"Interface.AnalogScrollSpeed"_F});
    }
    //Use this when you need to add more scrolling offset to a previous amount as GetScrollAmount() is used to get the internal scroll offset specifically.
    virtual inline vf2d GetTargetScrollAmount()const{
        return targetScrollOffset;
    }
    virtual bool GetHoverState(AiL*game,MenuComponent*child)override{
        return geom2d::overlaps(geom2d::rect<float>{Menu::menus[parentMenu]->pos+rect.pos,rect.size},game->GetMousePos())&& //Make sure the mouse is inside the parent window component first....
            geom2d::overlaps(geom2d::rect<float>{Menu::menus[parentMenu]->pos+rect.pos+child->rect.pos,child->rect.size},game->GetMousePos());
    }

    inline void IncreaseSelectionIndex(const float val){
        float prevIndex=selectionIndex;
	    selectionIndex=std::clamp(selectionIndex+val,0.f,float(components.size()-1));
        if(size_t(prevIndex)!=size_t(selectionIndex)){Menu::menus[parentMenu]->SetSelection(components[size_t(selectionIndex)],false);}
    }
protected:
    virtual inline vf2d GetScrollAmount()const{
        return scrollOffset;
    }
    virtual inline void AfterCreate()override{
        //Let's use the internal name of this component to add unique names for sub-components.
        upButton=Menu::menus[parentMenu]->ADD(name+vf2d(rect.pos+vf2d{rect.size.x-12,0}).str()+"_"+vf2d(12,12).str(),MenuComponent)(geom2d::rect<float>{rect.pos+vf2d{rect.size.x-12,0},{12,12}},"^",[&](MenuFuncData dat){SetScrollAmount(GetScrollAmount()+vf2d{0,"ThemeGlobal.MenuButtonScrollSpeed"_F});return true;},ButtonAttr::UNSELECTABLE_VIA_KEYBOARD)DEPTH depth-1 END; 
        downButton=Menu::menus[parentMenu]->ADD(name+vf2d(rect.pos+rect.size-vf2d{12,12}).str()+"_"+vf2d(12,12).str(),MenuComponent)(geom2d::rect<float>{rect.pos+rect.size-vf2d{12,12},{12,12}},"v",[&](MenuFuncData dat){SetScrollAmount(GetScrollAmount()-vf2d{0,"ThemeGlobal.MenuButtonScrollSpeed"_F});return true;},ButtonAttr::UNSELECTABLE_VIA_KEYBOARD)DEPTH depth-1 END;
        subWindow=ViewPort::rectViewPort({},rect.size,Menu::menus[parentMenu]->pos+rect.pos);
        if(!upButton.expired()){upButton.lock()->Enable(!disabled);}
        if(!downButton.expired()){downButton.lock()->Enable(!disabled);}
    }
    virtual inline void BeforeUpdate(AiL*game)override{
        MenuComponent::BeforeUpdate(game);
        for(std::weak_ptr<MenuComponent>component:components){
            std::shared_ptr<MenuComponent>componentPtr=component.lock();
            if(componentPtr->renderInMain)ERR(std::format("WARNING! Component {} is inside a ScrollableWindowComponent but renders in main instead! Parent Component: {}",componentPtr->GetName(),GetName()));
            componentPtr->_BeforeUpdate(game);
        }
    }
    virtual inline void Update(AiL*game)override{
	    MenuComponent::Update(game);

        lastScrollUpdate=std::max(0.f,lastScrollUpdate-game->GetElapsedTime());

        vf2d windowAbsPos=Menu::menus[parentMenu]->pos+rect.pos;

        bool mouseOverScrollbar=geom2d::overlaps(geom2d::rect<float>(windowAbsPos+vf2d{rect.size.x-12,scrollBarTop+12},{12,scrollBarHeight}),game->GetMousePos());

        if(mouseOverScrollbar||scrollBarSelected){
            scrollBarHoverTime=std::min(scrollBarHoverTime+game->GetElapsedTime(),"ThemeGlobal.HighlightTime"_F);
            if(game->GetMouse(0).bPressed&&!geom2d::contains(rect,bounds)){
                scrollBarSelected=true;
            }
            if(game->GetMouse(0).bReleased){
                scrollBarSelected=false;
            }
            if(scrollBarSelected){
                float spaceBetweenTopAndBottomArrows=rect.size.y-24;
                float viewHeight=rect.size.y;

                float totalContentHeight=bounds.size.y;
                if(totalContentHeight==0)totalContentHeight=1;
                float scrollBarScale=(spaceBetweenTopAndBottomArrows/totalContentHeight);
                //The scroll amount moves centered on the position the mouse is at.
                float newScrollbarTop=(game->GetMousePos().y-windowAbsPos.y-12)-scrollBarHeight/2;
                SetScrollAmount({GetScrollAmount().x,(-newScrollbarTop+1)/scrollBarScale});
            }
        }else{
            scrollBarHoverTime=std::max(scrollBarHoverTime-game->GetElapsedTime(),0.f);
        }

        if(game->GetMouseWheel()!=0){
            if(game->GetMouseWheel()>0){
                SetScrollAmount(GetTargetScrollAmount()+vf2d{0,"ThemeGlobal.MenuScrollWheelSpeed"_F});
            }else{
                SetScrollAmount(GetTargetScrollAmount()-vf2d{0,"ThemeGlobal.MenuScrollWheelSpeed"_F});
            }
        }

        if(bounds.size.y-rect.size.y>0){
            scrollOffset.y=std::clamp(GetScrollAmount().y,-(bounds.size.y-rect.size.y),0.f);
            SetScrollAmount({targetScrollOffset.x,std::clamp(targetScrollOffset.y,-(bounds.size.y-rect.size.y),0.f)});
            selectionIndex=std::clamp(selectionIndex,0.f,float(components.size()-1));
        }else{
            scrollOffset.y=0;
            SetScrollAmount({targetScrollOffset.x,0});
            selectionIndex=std::clamp(selectionIndex,0.f,float(components.size()-1));
        }
        
        std::sort(components.begin(),components.end(),[](std::weak_ptr<MenuComponent>c1,std::weak_ptr<MenuComponent>c2){return c1.lock()->depth>c2.lock()->depth;});        
        for(std::weak_ptr<MenuComponent>component:components){
            component.lock()->disabled=!OnScreen(component.lock());
            component.lock()->_Update(game);
        }

        upButton.lock()->disabled=false;
        downButton.lock()->disabled=false;
        if(geom2d::contains(rect,bounds)){//This means we have no reason to show a scrollbar.
            upButton.lock()->disabled=true;
            downButton.lock()->disabled=true;
        }

        #pragma region Move scroll offset towards target offset
        if(scrollOffset.y!=targetScrollOffset.y){
            if(lastScrollUpdate==0.f){
                float diff=fabs(targetScrollOffset.y-scrollOffset.y);

                if(targetScrollOffset.y>scrollOffset.y){
                    scrollOffset.y+=diff/4.f;
                    if(targetScrollOffset.y<scrollOffset.y){
                        scrollOffset.y=targetScrollOffset.y;
                    }
                }else{
                    scrollOffset.y-=diff/4.f;
                    if(targetScrollOffset.y>scrollOffset.y){
                        scrollOffset.y=targetScrollOffset.y;
                    }
                }

                for(std::weak_ptr<MenuComponent>component:components){
                    component.lock()->rect.pos=component.lock()->originalPos+scrollOffset;
                }
                lastScrollUpdate=1/60.f;
            }
        }
        #pragma endregion
    }
    inline void DrawScrollbar(ViewPort&window,vf2d parentPos,bool focused){
        float spaceBetweenTopAndBottomArrows=rect.size.y-24;
        float viewHeight=rect.size.y;
        float totalContentHeight=bounds.size.y;
        if(totalContentHeight==0)totalContentHeight=1;
        float scrollBarScale=(spaceBetweenTopAndBottomArrows/totalContentHeight);
        scrollBarHeight=std::min(spaceBetweenTopAndBottomArrows,viewHeight*scrollBarScale-1);
        scrollBarTop=-GetScrollAmount().y*scrollBarScale+1;

        float focusedWindowColorMult=(focused?1:"ThemeGlobal.MenuUnfocusedColorMult"_F);

        window.FillRectDecal(rect.pos+parentPos+vf2d{rect.size.x-12.f,scrollBarTop+12},{12,scrollBarHeight},PixelLerp(Menu::GetCurrentTheme().GetButtonCol(),Menu::GetCurrentTheme().GetHighlightCol(),scrollBarHoverTime/"ThemeGlobal.HighlightTime"_F)*focusedWindowColorMult);
        window.DrawRectDecal(rect.pos+parentPos+vf2d{rect.size.x-12.f,scrollBarTop+12},{12,scrollBarHeight},WHITE*focusedWindowColorMult);
    }

    inline float GetComponentIndex(std::weak_ptr<MenuComponent>comp){
        return float(std::distance(GetComponents().begin(),std::find_if(GetComponents().begin(),GetComponents().end(),[&](auto&component){return &*comp.lock()==&*component.lock();})));
    }

    virtual inline void DrawDecal(ViewPort&window,bool focused)override{
	    MenuComponent::DrawDecal(window,focused);
        if(border){
            window.DrawRectDecal(rect.pos,rect.size);
        }
        for(std::weak_ptr<MenuComponent>component:components){
            component.lock()->_DrawDecal(subWindow,focused);
        }
        if(!geom2d::contains(rect,bounds)){
            DrawScrollbar(window,{},focused);
        }
    }
    //Calculates the bounds of all components.
    inline void CalculateBounds(){
        bounds={};
        for(std::weak_ptr<MenuComponent>component:components){
            if(component.lock()->rect.pos.x<bounds.pos.x){
                float sizeIncrease=bounds.pos.x-component.lock()->rect.pos.x;
                bounds.size.x+=sizeIncrease;
                bounds.pos.x=component.lock()->rect.pos.x;
            }
            if(component.lock()->rect.right().start.x>bounds.right().start.x){
                float sizeIncrease=component.lock()->rect.right().start.x-bounds.right().start.x;
                bounds.size.x+=sizeIncrease;
            }
            if(component.lock()->rect.pos.y<bounds.pos.y){
                float sizeIncrease=bounds.pos.y-component.lock()->rect.pos.y;
                bounds.size.y+=sizeIncrease;
                bounds.pos.y=component.lock()->rect.pos.y;
            }
            if(component.lock()->rect.bottom().start.y>bounds.bottom().start.y){
                float sizeIncrease=component.lock()->rect.bottom().start.y-bounds.bottom().start.y;
                bounds.size.y+=sizeIncrease;
            }
        }
    }
public:
    template<class T>
    std::shared_ptr<T> _AddComponent(std::string key,std::shared_ptr<T>button){
        if(Menu::menus[parentMenu]->components.count(key)){
		    ERR("WARNING! Key "<<key<<" for menu"<<parentMenu<<" already exists! Key names must be unique!")
	    }

        components.push_back(button);
        button->renderInMain=false; //Now we are in control!
        button->parentComponent=DYNAMIC_POINTER_CAST<ScrollableWindowComponent>(Menu::menus[parentMenu]->components[this->GetName()]);
        button->disabled=disabled;

        CalculateBounds();

        Menu::menus[parentMenu]->_AddComponent(key,button);
        return button;
    }
    virtual inline bool PointWithinParent(MenuComponent*child,vi2d drawPos)override{
        return geom2d::overlaps(geom2d::rect<float>{Menu::menus[parentMenu]->pos+rect.pos,rect.size},drawPos);
    }
    virtual inline bool PointWithinParent(MenuComponent*child,geom2d::rect<float> drawRect)override{
        return geom2d::overlaps(geom2d::rect<float>{Menu::menus[parentMenu]->pos+rect.pos,rect.size},drawRect);
    }
    virtual inline bool HandleOutsideDisabledButtonSelection(std::weak_ptr<MenuComponent>disabledButton)override{
        //Set the offset so the center is highlighted by this button.
        SetScrollAmount(vf2d{GetScrollAmount().x,GetScrollAmount().y-disabledButton.lock()->rect.pos.y+disabledButton.lock()->rect.size.y});
        return true;
    };
    virtual void Cleanup()override{}
    inline std::vector<std::weak_ptr<MenuComponent>>&GetComponents(){
        return components;
    }
    virtual inline void Enable(bool enabled)override final{
        disabled=!enabled;
        for(std::weak_ptr<MenuComponent>component:components){
            component.lock()->Enable(enabled);
        }
        if(upButton.lock()){upButton.lock()->Enable(enabled);}
        if(downButton.lock()){downButton.lock()->Enable(enabled);}
    };
};