dyomedea/src/components/gpx/styles.ts

import { Fill, Text, Icon, Stroke, Style } from 'ol/style';
import startIcon from '../../icons/flag-start-b-svgrepo-com-green.svg';
import finishIcon from '../../icons/flag-finish-b-o-svgrepo-com-red.svg';
import wptIcon from '../../icons/location-pin-svgrepo-com-green.svg';
import houseIcon from '../../icons/house-svgrepo-com.svg';
import houseFlatIcon from '../../icons/houseFlat-svgrepo-com.svg';
import campingIcon from '../../icons/camping-14-svgrepo-com.svg';
import farmPigIcon from '../../icons/farm-pig-svgrepo-com.svg';
import cheeseIcon from '../../icons/cheese-svgrepo-com.svg';
import trainIcon from '../../icons/train-svgrepo-com.svg';
import picnicIcon from '../../icons/picnic-svgrepo-com.svg';
import caveIcon from '../../icons/cave-entrance-svgrepo-com.svg';
import wptIconSel from '../../icons/location-pin-svgrepo-com-red.svg';
import { Feature } from 'ol';
import memoize from 'memoizee';

interface StyleParameters {
  type: string;
  isSelected: boolean;
}

const icons = {
  house: {
    src: houseIcon,
    scale: 1 / 15,
    opacity: 0.9,
    anchor: [0.5, 1],
  },
  houseFlat: {
    src: houseFlatIcon,
    scale: 1 / 15,
    opacity: 0.9,
    anchor: [0.5, 1],
  },
  camping: {
    src: campingIcon,
    scale: 2,
    opacity: 0.9,
    anchor: [0.5, 1],
  },
  farmPig: {
    src: farmPigIcon,
    scale: 1 / 12,
    opacity: 0.9,
    anchor: [0.5, 1],
  },
  cheese: {
    src: cheeseIcon,
    scale: 3 / 4,
    opacity: 0.9,
    anchor: [0.5, 1],
  },
  train: {
    src: trainIcon,
    scale: 1 / 10,
    opacity: 0.9,
    anchor: [0.5, 1],
  },
  picnic: {
    src: picnicIcon,
    scale: 1 / 15,
    opacity: 0.9,
    anchor: [0.5, 1],
  },
  cave: {
    src: caveIcon,
    scale: 1 / 7,
    opacity: 0.9,
    anchor: [0.5, 1],
  },
};

const wptIconObj = {
  src: wptIcon,
  scale: 0.1,
  opacity: 0.9,
  anchor: [0.5, 1],
};

const textStroke = new Stroke({
  color: '#fff',
  width: 3,
});
const textFill = new Fill({
  color: '#000',
});
const textFillSel = new Fill({
  color: 'red',
});

const styles = {
  default: {
    trkseg: {
      stroke: new Stroke({
        color: 'blue',
        width: 3,
      }),
    },
    'trkseg-start': {
      image: new Icon({
        src: startIcon,
        scale: 0.2,
        opacity: 0.6,
        anchor: [0.5, 1],
      }),
    },
    'trkseg-finish': {
      image: new Icon({
        src: finishIcon,
        scale: 0.2,
        opacity: 0.6,
        anchor: [0.5, 1],
      }),
    },
    wpt: {
      image: (feature: Feature) => {
        const customIcon = icons[feature.get('sym') as keyof typeof icons];
        const icon = customIcon ?? wptIconObj;
        return new Icon(icon);
      },
      text: (feature: Feature) =>
        new Text({
          font: '16px Calibri,sans-serif',
          text: feature.get('name'),
          fill: textFill,
          stroke: textStroke,
          offsetY: -40,
        }),
    },
  },
  selected: {
    trkseg: {
      stroke: new Stroke({
        color: 'red',
        width: 3,
      }),
    },
    wpt: {
      image: new Icon({
        src: wptIconSel,
        scale: 0.1,
        opacity: 0.9,
        anchor: [0.5, 1],
      }),
      text: (feature: Feature) =>
        new Text({
          font: '16px Calibri,sans-serif',
          text: feature.get('name'),
          fill: textFillSel,
          stroke: textStroke,
          offsetY: -40,
        }),
    },
  },
};

const styleRequiresFeature = memoize((type: keyof typeof styles.default) => {
  const defaults = styles.default[type];
  const selected = styles.selected[type];
  const all = { ...defaults, ...selected };
  for (const key of Object.keys(all)) {
    if (all[key] instanceof Function) {
      return true;
    }
  }
  return false;
});

const getStyle = memoize(
  (
    type: keyof typeof styles.default,
    isSelected: boolean = false,
    params: any
  ) => {
    const defaults = styles.default[type];
    const selected = styles.selected[type];
    const all = isSelected ? { ...defaults, ...selected } : { ...defaults };
    // console.log({
    //   caller: 'style / getStyle',
    //   type,
    //   isSelected,
    //   params,
    //   defaults,
    //   selected,
    //   all,
    // });
    for (const key of Object.keys(all)) {
      if (all[key] instanceof Function) {
        all[key] = all[key](params);
      }
    }
    return new Style(all);
  },
  { length: 3, max: 1024 }
);

export const style = (feature: Feature, resolution: number) => {
  const type = feature.get('type');
  const isSelected = feature.get('isSelected') === true;
  // console.log({ caller: 'style', type, isSelected });
  if (styleRequiresFeature(type)) {
    return getStyle(type, isSelected, feature);
  }
  return getStyle(type, isSelected, null);
};

export default style;