/**
 * @license
 * Copyright 2021 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

/**
 * @fileoverview Utilities for bumping objects back into worksapce bounds.
 * @author fenichel@google.com (Rachel Fenichel)
 */
'use strict';

goog.module('Blockly.bumpObjects');

/* eslint-disable-next-line no-unused-vars */
const IBoundedElement = goog.requireType('Blockly.IBoundedElement');
/* eslint-disable-next-line no-unused-vars */
const MetricsManager = goog.requireType('Blockly.MetricsManager');
/* eslint-disable-next-line no-unused-vars */
const WorkspaceSvg = goog.requireType('Blockly.WorkspaceSvg');
const mathUtils = goog.require('Blockly.utils.math');


/**
 * Bumps the given object that has passed out of bounds.
 * @param {!WorkspaceSvg} workspace The workspace containing the object.
 * @param {!MetricsManager.ContainerRegion} scrollMetrics Scroll metrics
 *    in workspace coordinates.
 * @param {!IBoundedElement} object The object to bump.
 * @return {boolean} True if block was bumped.
 */
const bumpObjectIntoBounds = function(workspace, scrollMetrics, object) {
  // Compute new top/left position for object.
  const objectMetrics = object.getBoundingRectangle();
  const height = objectMetrics.bottom - objectMetrics.top;
  const width = objectMetrics.right - objectMetrics.left;

  const topClamp = scrollMetrics.top;
  const scrollMetricsBottom = scrollMetrics.top + scrollMetrics.height;
  const bottomClamp = scrollMetricsBottom - height;
  // If the object is taller than the workspace we want to
  // top-align the block
  const newYPosition =
      mathUtils.clamp(topClamp, objectMetrics.top, bottomClamp);
  const deltaY = newYPosition - objectMetrics.top;

  // Note: Even in RTL mode the "anchor" of the object is the
  // top-left corner of the object.
  let leftClamp = scrollMetrics.left;
  const scrollMetricsRight = scrollMetrics.left + scrollMetrics.width;
  let rightClamp = scrollMetricsRight - width;
  if (workspace.RTL) {
    // If the object is wider than the workspace and we're in RTL
    // mode we want to right-align the block, which means setting
    // the left clamp to match.
    leftClamp = Math.min(rightClamp, leftClamp);
  } else {
    // If the object is wider than the workspace and we're in LTR
    // mode we want to left-align the block, which means setting
    // the right clamp to match.
    rightClamp = Math.max(leftClamp, rightClamp);
  }
  const newXPosition =
      mathUtils.clamp(leftClamp, objectMetrics.left, rightClamp);
  const deltaX = newXPosition - objectMetrics.left;

  if (deltaX || deltaY) {
    object.moveBy(deltaX, deltaY);
    return true;
  }
  return false;
};
exports.bumpIntoBounds = bumpObjectIntoBounds;