svgedit/src/editor/extensions/ext-polygon/ext-polygon.js

/**
 * @file ext-polygon.js
 *
 *
 * @copyright 2010 CloudCanvas, Inc. All rights reserved
 *
 */

const loadExtensionTranslation = async function (lang) {
  let translationModule;
  try {
    // eslint-disable-next-line no-unsanitized/method
    translationModule = await import(`./locale/${encodeURIComponent(lang)}.js`);
  } catch (_error) {
    // eslint-disable-next-line no-console
    console.error(`Missing translation (${lang}) - using 'en'`);
    translationModule = await import(`./locale/en.js`);
  }
  return translationModule.default;
};

export default {
  name: 'polygon',
  async init (_S) {
    const svgEditor = this;
    const {svgCanvas} = svgEditor;
    const {$id} = svgCanvas;
    // const  editingitex = false;
    const strings = await loadExtensionTranslation(svgEditor.configObj.pref('lang'));
    let selElems;
    let started;
    let newFO;
    /**
    * @param {boolean} on
    * @returns {void}
    */
    const showPanel = (on) => {
      $id('polygon_panel').style.display = (on) ? 'block' : 'none';
    }   

    /**
    * @param {string} attr
    * @param {string|Float} val
    * @returns {void}
    */
    const setAttr = (attr, val) => {
      svgCanvas.changeSelectedAttribute(attr, val);
      svgCanvas.call('changed', selElems);
    }

    /**
    * @param {Float} n
    * @returns {Float}
    */
    const cot = (n) => (1 / Math.tan(n));

    /**
    * @param {Float} n
    * @returns {Float}
    */
    const sec = (n) => (1 / Math.cos(n));

    return {
      name: strings.name,
      // The callback should be used to load the DOM with the appropriate UI items
      callback () {
        // Add the button and its handler(s)
        // Note: the star extension may also add the same flying button so we check first
        if ($id('tools_polygon') === null) {
          const buttonTemplate = document.createElement("template");
          buttonTemplate.innerHTML = `
            <se-flyingbutton id="tools_polygon" title="Polygone/Star Tool">
              <se-button id="tool_polygon" title="Polygon Tool" src="./images/polygon.svg"></se-button>
              <se-button id="tool_star" title="Star Tool" src="./images/star.svg"></se-button>
            </se-flyingbutton>
          `
          $id('tools_left').append(buttonTemplate.content.cloneNode(true));
        }
        $id('tool_polygon').addEventListener("click", () => {
          if (this.leftPanel.updateLeftPanel('tool_polygon')) {
            svgCanvas.setMode('polygon');
            showPanel(true);
          }   
        }); 

        // Add the context panel and its handler(s)
        const panelTemplate = document.createElement("template");
        panelTemplate.innerHTML = `
          <div id="polygon_panel">
            <se-spin-input size="3" id="polySides" min=1 step=1 value=5 label="sides">
            </se-spin-input>
          </div>
        `
        $id('tools_top').appendChild(panelTemplate.content.cloneNode(true));
        $id("polygon_panel").style.display = 'none';
        $id("polySides").addEventListener("change", (event) => {
          setAttr('sides', event.target.value);
        });
      },
      mouseDown (opts) {
        if (svgCanvas.getMode() !== 'polygon') {
          return undefined;
        }
        // const e = opts.event;
        const rgb = svgCanvas.getColor('fill');
        // const ccRgbEl = rgb.substring(1, rgb.length);
        const sRgb = svgCanvas.getColor('stroke');
        // ccSRgbEl = sRgb.substring(1, rgb.length);
        const sWidth = svgCanvas.getStrokeWidth();

        started = true;

        newFO = svgCanvas.addSVGElementFromJson({
          element: 'polygon',
          attr: {
            cx: opts.start_x,
            cy: opts.start_y,
            id: svgCanvas.getNextId(),
            shape: 'regularPoly',
            sides: document.getElementById('polySides').value,
            orient: 'x',
            edge: 0,
            fill: rgb,
            strokecolor: sRgb,
            strokeWidth: sWidth
          }
        });

        return {
          started: true
        };
      },
      mouseMove (opts) {
        if (!started || svgCanvas.getMode() !== 'polygon') {
          return undefined;
        }
        const cx = Number(newFO.getAttribute('cx'));
        const cy = Number(newFO.getAttribute('cy'));
        const sides = Number(newFO.getAttribute('sides'));
        // const orient = newFO.getAttribute('orient');
        const fill = newFO.getAttribute('fill');
        const strokecolor = newFO.getAttribute('strokecolor');
        const strokeWidth = Number(newFO.getAttribute('strokeWidth'));
  
        let x = opts.mouse_x;
        let y = opts.mouse_y;

        const edg = (Math.sqrt((x - cx) * (x - cx) + (y - cy) * (y - cy))) / 1.5;
        newFO.setAttribute('edge', edg);

        const inradius = (edg / 2) * cot(Math.PI / sides);
        const circumradius = inradius * sec(Math.PI / sides);
        let points = '';
        for (let s = 0; sides >= s; s++) {
          const angle = 2.0 * Math.PI * s / sides;
          x = (circumradius * Math.cos(angle)) + cx;
          y = (circumradius * Math.sin(angle)) + cy;

          points += x + ',' + y + ' ';
        }

        // const poly = newFO.createElementNS(NS.SVG, 'polygon');
        newFO.setAttribute('points', points);
        newFO.setAttribute('fill', fill);
        newFO.setAttribute('stroke', strokecolor);
        newFO.setAttribute('stroke-width', strokeWidth);
        return {
          started: true
        };
      },

      mouseUp () {
        if (svgCanvas.getMode() !== 'polygon') {
          return undefined;
        }
        const edge = newFO.getAttribute('edge');
        const keep = (edge !== '0');
        // svgCanvas.addToSelection([newFO], true);
        return {
          keep,
          element: newFO
        };
      },
      selectedChanged (opts) {
        // Use this to update the current selected elements
        selElems = opts.elems;

        let i = selElems.length;
        while (i--) {
          const elem = selElems[i];
          if (elem && elem.getAttribute('shape') === 'regularPoly') {
            if (opts.selectedElement && !opts.multiselected) {
              $id('polySides').value = elem.getAttribute('sides');

              showPanel(true);
            } else {
              showPanel(false);
            }
          } else {
            showPanel(false);
          }
        }
      },
      elementChanged () {
        // const elem = opts.elems[0];
      }
    };
  }
};