#include <allegro.h>

#include "InputScrollbar.h"

void InputScrollbar::scrollUp() {
     setValue(value - 1);
}
void InputScrollbar::scrollDown() {
     setValue(value + 1);
}

int InputScrollbar::getValue() {
    return value;
}
void InputScrollbar::setValue(int desiredValue) {
    value = desiredValue;
    if (desiredValue > limit)
       desiredValue = limit;
    if (desiredValue < 0)
       desiredValue = 0;
    
    func();
}

void InputScrollbar::setLimit(int desiredLimit) {
     limit = desiredLimit;
     setValue(0);
}

InputGuiElementCallback* InputScrollbar::getUpButtonPointer() {
                         return &upButton;
}
InputGuiElementCallback* InputScrollbar::getDownButtonPointer() {
                         return &downButton;
}

bool InputScrollbar::acknowledgeMouse() {
     const int mousePosition = mouse_pos;
     const int mouseButtons = mouse_b;
     
     if ((mouseButtons & 0x1) &&
         (mousePosition >> 16) >= x && (mousePosition >> 16) < x + w &&
         (mousePosition & 0xffff) >= y + upButton.getH() &&
         (mousePosition & 0xffff) < y + h - downButton.getH()) {
        setValue(((mousePosition & 0xffff) - (y + upButton.getH())) * limit /
          (h - upButton.getH() - downButton.getH() - 1));
        return true;
     } else
        return false;
}

void InputScrollbar::focus() {}
void InputScrollbar::blur() {}

void InputScrollbar::shift(int xOffset, int yOffset) {
     x += xOffset;
     y += yOffset;
}
bool InputScrollbar::within(int xTarget, int yTarget) {
     return xTarget >= x && xTarget < x + w &&
            yTarget >= y && yTarget < y + h;
}
void InputScrollbar::draw() {
     upButton.draw();
     downButton.draw();
     
     vline(canvas, x, y + upButton.getH(), y + h - downButton.getH() - 1, 15);
     vline(canvas, x + w - 1, y + upButton.getH(), y + h - downButton.getH() -
       1, 15);
     hline(canvas, x + 1, y + upButton.getH() + (limit == 0 ? 0 : value * (h -
       upButton.getH() - downButton.getH() - 1) / limit), x + w - 2,
       interactivityColor);
}
void InputScrollbar::erase() {
     rectfill(canvas, x, y, x + w - 1, y + h - 1, 0);
}