darkness-dependent-vision/src/module/darkness-dependent-vision.js

// SPDX-FileCopyrightText: 2021 Johannes Loher
//
// SPDX-License-Identifier: MIT

'use strict';

import logger from './logger';
import { libWrapper } from './shims/libWrapperShim';
import notifications from './notifications';

const packageName = 'darkness-dependent-vision';

Hooks.once('init', async () => {
  logger.info(`Initializing ${packageName}`);

  try {
    libWrapper.register('darkness-dependent-vision', 'Token.prototype.dimRadius', getDimRadius, 'OVERRIDE');
  } catch (e) {
    notifications.warn(game.i18n.format('DDV.ErrorFailedToOverride', { target: 'Token.prototype.dimRadius' }), {
      log: true,
    });
  }

  try {
    libWrapper.register('darkness-dependent-vision', 'Token.prototype.brightRadius', getBrightRadius, 'OVERRIDE');
  } catch (e) {
    notifications.warn(game.i18n.format('DDV.ErrorFailedToOverride', { target: 'Token.prototype.brightRadius' }), {
      log: true,
    });
  }

  libWrapper.register('darkness-dependent-vision', 'Token.prototype.updateSource', updateSource, 'WRAPPER');
});

/**
 * Does this {@link Token} have dim vision, considering the darkness level of
 * its containing {@link Scene}?
 */
function hasDimVision() {
  const dimVisionDarknessLowerBound = this.document.getFlag(packageName, 'dimVisionDarknessLowerBound') ?? -1;
  const dimVisionDarknessUpperBound = this.document.getFlag(packageName, 'dimVisionDarknessUpperBound') ?? 2;
  return (
    this.document.parent.data.darkness >= dimVisionDarknessLowerBound &&
    this.document.parent.data.darkness < dimVisionDarknessUpperBound
  );
}

/**
 * Does this {@link Token} have bright vision, considering the darkness level of
 * its containing {@link Scene}?
 */
function hasBrightVision() {
  const brightVisionDarknessLowerBound = this.document.getFlag(packageName, 'brightVisionDarknessLowerBound') ?? -1;
  const brightVisionDarknessUpperBound = this.document.getFlag(packageName, 'brightVisionDarknessUpperBound') ?? 2;
  return (
    this.document.parent.data.darkness >= brightVisionDarknessLowerBound &&
    this.document.parent.data.darkness < brightVisionDarknessUpperBound
  );
}

/**
 * Get this {@link Token}'s dim vision distance of in grid units, considering
 * the darkness level of its containing {@link Scene}.
 *
 * @returns {number} The the number of grid units that this {@link Token} has
 * dim vision
 */
function getDimVision() {
  return hasDimVision.call(this) ? this.data.dimSight : 0;
}

/**
 * Get this {@link Token}'s bright vision distance in grid units, considering
 * the darkness level of its containing {@link Scene}.
 *
 * @returns {number} The the number of grid units that this {@link Token} has
 * bright vision
 */
function getBrightVision() {
  return hasBrightVision.call(this) ? this.data.brightSight : 0;
}

/**
 * Translate the token's sight distance in units into a radius in pixels.
 * @return {number} The sight radius in pixels
 */
function getDimRadius() {
  const dimSight = getDimVision.call(this);
  let r = Math.abs(this.data.dimLight) > Math.abs(dimSight) ? this.data.dimLight : dimSight;
  return this.getLightRadius(r);
}

/**
 * Translate the token's bright light distance in units into a radius in pixels.
 * @return {number} The bright radius in pixels
 */
function getBrightRadius() {
  const brightSight = getBrightVision.call(this);
  let r = Math.abs(this.data.brightLight) > Math.abs(brightSight) ? this.data.brightLight : brightSight;
  return this.getLightRadius(r);
}

/**
 * @typedef {({defer, deleted, noUpdateFog}?: {defer?: boolean, deleted?: boolean, noUpdateFog?: boolean}) => void} UpdateSourceFunction
 */

/**
 * Update the light and vision source objects associated with this Token
 * @param {UpdateSourceFunction} wrapped       The function that is wrapped by this function and needs to be called next in the chain
 * @param {boolean}              [defer]       Defer refreshing the SightLayer to manually call that refresh later.
 * @param {boolean}              [deleted]     Indicate that this light source has been deleted.
 * @param {boolean}              [noUpdateFog] Never update the Fog exploration progress for this update.
 */
function updateSource(wrapped, { defer = false, deleted = false, noUpdateFog = false } = {}) {
  wrapped({ defer, deleted, noUpdateFog });

  // Prepare some common data
  const origin = this.getSightOrigin();
  const sourceId = this.sourceId;
  const d = canvas.dimensions;

  // Update vision source
  const isVisionSource = this._isVisionSource();
  if (isVisionSource && !deleted) {
    const dimSight = getDimVision.call(this);
    const brightSight = getBrightVision.call(this);
    let dim = Math.min(this.getLightRadius(dimSight), d.maxR);
    const bright = Math.min(this.getLightRadius(brightSight), d.maxR);
    this.vision.initialize({
      x: origin.x,
      y: origin.y,
      dim: dim,
      bright: bright,
      angle: this.data.sightAngle,
      rotation: this.data.rotation,
    });
    canvas.sight.sources.set(sourceId, this.vision);
    if (!defer) {
      this.vision.drawLight();
      canvas.sight.refresh({ noUpdateFog });
    }
  } else {
    canvas.sight.sources.delete(sourceId);
    if (isVisionSource && !defer) canvas.sight.refresh();
  }
}

Hooks.on('updateScene', (scene, change) => {
  if (change.darkness != null) {
    scene.getEmbeddedCollection('Token').forEach((tokenDocument) => tokenDocument.object.updateSource());
  }
});

Hooks.on('updateToken', (token, change) => {
  const shouldUpdateSource = [
    'dimVisionDarknessLowerBound',
    'dimVisionDarknessUpperBound',
    'brightVisionDarknessLowerBound',
    'brightVisionDarknessUpperBound',
  ].some((flagKey) => `flags.darkness-dependent-vision.${flagKey}` in foundry.utils.flattenObject(change));
  if (shouldUpdateSource) {
    token.object.updateSource();
  }
});