react-selectable-box/lib/hooks/useScroll.js

A React component used hooks that allows you to select elements in the drag area using the mouse

var __defProp = Object.defineProperty;
var __getOwnPropDesc = Object.getOwnPropertyDescriptor;
var __getOwnPropNames = Object.getOwnPropertyNames;
var __hasOwnProp = Object.prototype.hasOwnProperty;
var __export = (target, all) => {
  for (var name in all)
    __defProp(target, name, { get: all[name], enumerable: true });
};
var __copyProps = (to, from, except, desc) => {
  if (from && typeof from === "object" || typeof from === "function") {
    for (let key of __getOwnPropNames(from))
      if (!__hasOwnProp.call(to, key) && key !== except)
        __defProp(to, key, { get: () => from[key], enumerable: !(desc = __getOwnPropDesc(from, key)) || desc.enumerable });
  }
  return to;
};
var __toCommonJS = (mod) => __copyProps(__defProp({}, "__esModule", { value: true }), mod);

// src/hooks/useScroll.ts
var useScroll_exports = {};
__export(useScroll_exports, {
  default: () => useScroll
});
module.exports = __toCommonJS(useScroll_exports);
var import_react = require("react");
var import_utils = require("../utils");
var DEFAULT_SCROLL_SPEED = 4;
var EDGE_OFFSET = 1;
function useScroll(scrollSpeed = DEFAULT_SCROLL_SPEED, scrollContainer) {
  const topRaf = (0, import_react.useRef)(null);
  const bottomRaf = (0, import_react.useRef)(null);
  const leftRaf = (0, import_react.useRef)(null);
  const rightRaf = (0, import_react.useRef)(null);
  const cancelRaf = (raf) => {
    if (raf.current) {
      cancelAnimationFrame(raf.current);
      raf.current = null;
    }
  };
  const cancelScroll = () => {
    cancelRaf(topRaf);
    cancelRaf(bottomRaf);
    cancelRaf(leftRaf);
    cancelRaf(rightRaf);
  };
  (0, import_react.useEffect)(() => {
    return cancelScroll;
  }, []);
  const getScrollContainer = (axis) => {
    function getContainer() {
      var _a, _b;
      if (scrollContainer) {
        if (typeof scrollContainer === "function") {
          return scrollContainer();
        }
        if (((_a = scrollContainer.inner) == null ? void 0 : _a.axis) === axis) {
          return scrollContainer.inner.getContainer();
        }
        if (((_b = scrollContainer.outer) == null ? void 0 : _b.axis) === axis) {
          return scrollContainer.outer.getContainer();
        }
      }
      return document.body;
    }
    const container = getContainer();
    return container === document.body ? document.documentElement : container;
  };
  const smoothScroll = (e) => {
    const { clientX, clientY } = (0, import_utils.getClientXY)(e);
    const xScrollContainer = getScrollContainer("x");
    const yScrollContainer = getScrollContainer("y");
    if (yScrollContainer) {
      if (clientY - EDGE_OFFSET <= 0 || clientY <= yScrollContainer.getBoundingClientRect().top) {
        if (!topRaf.current) {
          const callback = () => {
            if (yScrollContainer.scrollTop > 0) {
              topRaf.current = requestAnimationFrame(() => {
                yScrollContainer.scrollTop -= scrollSpeed;
                callback();
              });
            }
          };
          callback();
        }
      } else {
        cancelRaf(topRaf);
      }
      if (clientY + EDGE_OFFSET >= window.innerHeight || clientY >= yScrollContainer.getBoundingClientRect().bottom) {
        if (!bottomRaf.current) {
          const callback = () => {
            if (yScrollContainer.scrollTop < yScrollContainer.scrollHeight - yScrollContainer.clientHeight) {
              bottomRaf.current = requestAnimationFrame(() => {
                yScrollContainer.scrollTop += scrollSpeed;
                callback();
              });
            }
          };
          callback();
        }
      } else {
        cancelRaf(bottomRaf);
      }
    }
    if (xScrollContainer) {
      if (clientX - EDGE_OFFSET <= 0 || clientX <= xScrollContainer.getBoundingClientRect().left) {
        if (!leftRaf.current) {
          const callback = () => {
            if (xScrollContainer.scrollLeft > 0) {
              leftRaf.current = requestAnimationFrame(() => {
                xScrollContainer.scrollLeft -= scrollSpeed;
                callback();
              });
            }
          };
          callback();
        }
      } else {
        cancelRaf(leftRaf);
      }
      if (clientX + EDGE_OFFSET >= window.innerWidth || clientX >= xScrollContainer.getBoundingClientRect().right) {
        if (!rightRaf.current) {
          const callback = () => {
            if (xScrollContainer.scrollLeft < xScrollContainer.scrollWidth - xScrollContainer.clientWidth) {
              rightRaf.current = requestAnimationFrame(() => {
                xScrollContainer.scrollLeft += scrollSpeed;
                callback();
              });
            }
          };
          callback();
        }
      } else {
        cancelRaf(rightRaf);
      }
    }
  };
  return {
    cancelScroll,
    smoothScroll
  };
}