/**
 * @file ext-eyedropper.js
 *
 * @license MIT
 *
 * @copyright 2010 Jeff Schiller
 *
 */

const loadExtensionTranslation = async function (lang) {
  let translationModule;
  try {
    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: 'eyedropper',
  async init (S) {
    const svgEditor = this;
    const strings = await loadExtensionTranslation(svgEditor.configObj.pref('lang'));
    const {$, ChangeElementCommand} = S, // , svgcontent,
      // svgdoc = S.svgroot.parentNode.ownerDocument,
      {svgCanvas} = svgEditor,
      addToHistory = function (cmd) { svgCanvas.undoMgr.addCommandToHistory(cmd); },
      currentStyle = {
        fillPaint: 'red', fillOpacity: 1.0,
        strokePaint: 'black', strokeOpacity: 1.0,
        strokeWidth: 5, strokeDashArray: null,
        opacity: 1.0,
        strokeLinecap: 'butt',
        strokeLinejoin: 'miter'
      };

    /**
     *
     * @param {module:svgcanvas.SvgCanvas#event:ext_selectedChanged|module:svgcanvas.SvgCanvas#event:ext_elementChanged} opts
     * @returns {void}
     */
    function getStyle (opts) {
      // if we are in eyedropper mode, we don't want to disable the eye-dropper tool
      const mode = svgCanvas.getMode();
      if (mode === 'eyedropper') { return; }

      const tool = $('#tool_eyedropper');
      // enable-eye-dropper if one element is selected
      let elem = null;
      if (!opts.multiselected && opts.elems[0] &&
        !['svg', 'g', 'use'].includes(opts.elems[0].nodeName)
      ) {
        elem = opts.elems[0];
        tool.removeClass('disabled');
        // grab the current style
        currentStyle.fillPaint = elem.getAttribute('fill') || 'black';
        currentStyle.fillOpacity = elem.getAttribute('fill-opacity') || 1.0;
        currentStyle.strokePaint = elem.getAttribute('stroke');
        currentStyle.strokeOpacity = elem.getAttribute('stroke-opacity') || 1.0;
        currentStyle.strokeWidth = elem.getAttribute('stroke-width');
        currentStyle.strokeDashArray = elem.getAttribute('stroke-dasharray');
        currentStyle.strokeLinecap = elem.getAttribute('stroke-linecap');
        currentStyle.strokeLinejoin = elem.getAttribute('stroke-linejoin');
        currentStyle.opacity = elem.getAttribute('opacity') || 1.0;
      // disable eye-dropper tool
      } else {
        tool.addClass('disabled');
      }
    }

    const events = {
      id: 'tool_eyedropper',
      click () {
        svgCanvas.setMode('eyedropper');
      }
    };

    return {
      name: strings.name,
      events,
      // if we have selected an element, grab its paint and enable the eye dropper button
      selectedChanged: getStyle,
      elementChanged: getStyle,
      mouseDown (opts) {
        const mode = svgCanvas.getMode();
        if (mode === 'eyedropper') {
          const e = opts.event;
          const {target} = e;
          if (!['svg', 'g', 'use'].includes(target.nodeName)) {
            const changes = {};

            const change = function (elem, attrname, newvalue) {
              changes[attrname] = elem.getAttribute(attrname);
              elem.setAttribute(attrname, newvalue);
            };

            if (currentStyle.fillPaint) { change(target, 'fill', currentStyle.fillPaint); }
            if (currentStyle.fillOpacity) { change(target, 'fill-opacity', currentStyle.fillOpacity); }
            if (currentStyle.strokePaint) { change(target, 'stroke', currentStyle.strokePaint); }
            if (currentStyle.strokeOpacity) { change(target, 'stroke-opacity', currentStyle.strokeOpacity); }
            if (currentStyle.strokeWidth) { change(target, 'stroke-width', currentStyle.strokeWidth); }
            if (currentStyle.strokeDashArray) { change(target, 'stroke-dasharray', currentStyle.strokeDashArray); }
            if (currentStyle.opacity) { change(target, 'opacity', currentStyle.opacity); }
            if (currentStyle.strokeLinecap) { change(target, 'stroke-linecap', currentStyle.strokeLinecap); }
            if (currentStyle.strokeLinejoin) { change(target, 'stroke-linejoin', currentStyle.strokeLinejoin); }

            addToHistory(new ChangeElementCommand(target, changes));
          }
        }
      }
    };
  }
};