svgedit/editor/extensions/ext-markers.js

/* globals jQuery */
/*
 * ext-markers.js
 *
 * Licensed under the Apache License, Version 2
 *
 * Copyright(c) 2010 Will Schleter
 *   based on ext-arrows.js by Copyright(c) 2010 Alexis Deveria
 *
 * This extension provides for the addition of markers to the either end
 * or the middle of a line, polyline, path, polygon.
 *
 * Markers may be either a graphic or arbitary text
 *
 * to simplify the coding and make the implementation as robust as possible,
 * markers are not shared - every object has its own set of markers.
 * this relationship is maintained by a naming convention between the
 * ids of the markers and the ids of the object
 *
 * The following restrictions exist for simplicty of use and programming
 *    objects and their markers to have the same color
 *    marker size is fixed
 *    text marker font, size, and attributes are fixed
 *    an application specific attribute - se_type - is added to each marker element
 *        to store the type of marker
 *
 * TODO:
 *    remove some of the restrictions above
 *    add option for keeping text aligned to horizontal
 *    add support for dimension extension lines
 *
 */
import svgEditor from '../svg-editor.js';
svgEditor.addExtension('Markers', function (S) {
  const $ = jQuery;
  const svgCanvas = svgEditor.canvas;
  const // {svgcontent} = S,
    addElem = S.addSvgElementFromJson;
  const mtypes = ['start', 'mid', 'end'];
  const markerPrefix = 'se_marker_';
  const idPrefix = 'mkr_';

  // note - to add additional marker types add them below with a unique id
  // and add the associated icon(s) to marker-icons.svg
  // the geometry is normallized to a 100x100 box with the origin at lower left
  // Safari did not like negative values for low left of viewBox
  // remember that the coordinate system has +y downward
  const markerTypes = {
    nomarker: {},
    leftarrow:
      {element: 'path', attr: {d: 'M0,50 L100,90 L70,50 L100,10 Z'}},
    rightarrow:
      {element: 'path', attr: {d: 'M100,50 L0,90 L30,50 L0,10 Z'}},
    textmarker:
      {element: 'text', attr: {x: 0, y: 0, 'stroke-width': 0, stroke: 'none', 'font-size': 75, 'font-family': 'serif', 'text-anchor': 'left',
        'xml:space': 'preserve'}},
    forwardslash:
      {element: 'path', attr: {d: 'M30,100 L70,0'}},
    reverseslash:
      {element: 'path', attr: {d: 'M30,0 L70,100'}},
    verticalslash:
      {element: 'path', attr: {d: 'M50,0 L50,100'}},
    box:
      {element: 'path', attr: {d: 'M20,20 L20,80 L80,80 L80,20 Z'}},
    star:
      {element: 'path', attr: {d: 'M10,30 L90,30 L20,90 L50,10 L80,90 Z'}},
    xmark:
      {element: 'path', attr: {d: 'M20,80 L80,20 M80,80 L20,20'}},
    triangle:
      {element: 'path', attr: {d: 'M10,80 L50,20 L80,80 Z'}},
    mcircle:
      {element: 'circle', attr: {r: 30, cx: 50, cy: 50}}
  };

  const langList = {
    en: [
      {id: 'start_marker_list', title: 'Select start marker type'},
      {id: 'mid_marker_list', title: 'Select mid marker type'},
      {id: 'end_marker_list', title: 'Select end marker type'},
      {id: 'nomarker', title: 'No Marker'},
      {id: 'leftarrow', title: 'Left Arrow'},
      {id: 'rightarrow', title: 'Right Arrow'},
      {id: 'textmarker', title: 'Text Marker'},
      {id: 'forwardslash', title: 'Forward Slash'},
      {id: 'reverseslash', title: 'Reverse Slash'},
      {id: 'verticalslash', title: 'Vertical Slash'},
      {id: 'box', title: 'Box'},
      {id: 'star', title: 'Star'},
      {id: 'xmark', title: 'X'},
      {id: 'triangle', title: 'Triangle'},
      {id: 'mcircle', title: 'Circle'},
      {id: 'leftarrow_o', title: 'Open Left Arrow'},
      {id: 'rightarrow_o', title: 'Open Right Arrow'},
      {id: 'box_o', title: 'Open Box'},
      {id: 'star_o', title: 'Open Star'},
      {id: 'triangle_o', title: 'Open Triangle'},
      {id: 'mcircle_o', title: 'Open Circle'}
    ]
  };

  // duplicate shapes to support unfilled (open) marker types with an _o suffix
  $.each(['leftarrow', 'rightarrow', 'box', 'star', 'mcircle', 'triangle'], function (i, v) {
    markerTypes[v + '_o'] = markerTypes[v];
  });

  /**
  * @param elem - A graphic element will have an attribute like marker-start
  * @param attr - marker-start, marker-mid, or marker-end
  * @returns The marker element that is linked to the graphic element
  */
  function getLinked (elem, attr) {
    const str = elem.getAttribute(attr);
    if (!str) { return null; }
    const m = str.match(/\(#(.*)\)/);
    if (!m || m.length !== 2) {
      return null;
    }
    return S.getElem(m[1]);
  }

  function setIcon (pos, id) {
    if (id.substr(0, 1) !== '\\') { id = '\\textmarker'; }
    const ci = '#' + idPrefix + pos + '_' + id.substr(1);
    svgEditor.setIcon('#cur_' + pos + '_marker_list', $(ci).children());
    $(ci).addClass('current').siblings().removeClass('current');
  }

  let selElems;
  // toggles context tool panel off/on
  // sets the controls with the selected element's settings
  function showPanel (on) {
    $('#marker_panel').toggle(on);

    if (on) {
      const el = selElems[0];

      let val, ci;
      $.each(mtypes, function (i, pos) {
        const m = getLinked(el, 'marker-' + pos);
        const txtbox = $('#' + pos + '_marker');
        if (!m) {
          val = '\\nomarker';
          ci = val;
          txtbox.hide(); // hide text box
        } else {
          if (!m.attributes.se_type) { return; } // not created by this extension
          val = '\\' + m.attributes.se_type.textContent;
          ci = val;
          if (val === '\\textmarker') {
            val = m.lastChild.textContent;
            // txtbox.show(); // show text box
          } else {
            txtbox.hide(); // hide text box
          }
        }
        txtbox.val(val);
        setIcon(pos, ci);
      });
    }
  }

  function addMarker (id, val) {
    const txtBoxBg = '#ffffff';
    const txtBoxBorder = 'none';
    const txtBoxStrokeWidth = 0;

    let marker = S.getElem(id);
    if (marker) { return; }

    if (val === '' || val === '\\nomarker') { return; }

    const el = selElems[0];
    const color = el.getAttribute('stroke');
    // NOTE: Safari didn't like a negative value in viewBox
    // so we use a standardized 0 0 100 100
    // with 50 50 being mapped to the marker position
    const strokeWidth = 10;
    let refX = 50;
    let refY = 50;
    let viewBox = '0 0 100 100';
    let markerWidth = 5;
    let markerHeight = 5;
    let seType;
    if (val.substr(0, 1) === '\\') {
      seType = val.substr(1);
    } else { seType = 'textmarker'; }

    if (!markerTypes[seType]) { return; } // an unknown type!

    // create a generic marker
    marker = addElem({
      element: 'marker',
      attr: {
        id,
        markerUnits: 'strokeWidth',
        orient: 'auto',
        style: 'pointer-events:none',
        se_type: seType
      }
    });

    if (seType !== 'textmarker') {
      const mel = addElem(markerTypes[seType]);
      const fillcolor = (seType.substr(-2) === '_o')
        ? 'none'
        : color;

      mel.setAttribute('fill', fillcolor);
      mel.setAttribute('stroke', color);
      mel.setAttribute('stroke-width', strokeWidth);
      marker.appendChild(mel);
    } else {
      const text = addElem(markerTypes[seType]);
      // have to add text to get bounding box
      text.textContent = val;
      const tb = text.getBBox();
      // alert(tb.x + ' ' + tb.y + ' ' + tb.width + ' ' + tb.height);
      const pad = 1;
      const bb = tb;
      bb.x = 0;
      bb.y = 0;
      bb.width += pad * 2;
      bb.height += pad * 2;
      // shift text according to its size
      text.setAttribute('x', pad);
      text.setAttribute('y', bb.height - pad - tb.height / 4); // kludge?
      text.setAttribute('fill', color);
      refX = bb.width / 2 + pad;
      refY = bb.height / 2 + pad;
      viewBox = bb.x + ' ' + bb.y + ' ' + bb.width + ' ' + bb.height;
      markerWidth = bb.width / 10;
      markerHeight = bb.height / 10;

      const box = addElem({
        element: 'rect',
        attr: {
          x: bb.x,
          y: bb.y,
          width: bb.width,
          height: bb.height,
          fill: txtBoxBg,
          stroke: txtBoxBorder,
          'stroke-width': txtBoxStrokeWidth
        }
      });
      marker.setAttribute('orient', 0);
      marker.appendChild(box);
      marker.appendChild(text);
    }

    marker.setAttribute('viewBox', viewBox);
    marker.setAttribute('markerWidth', markerWidth);
    marker.setAttribute('markerHeight', markerHeight);
    marker.setAttribute('refX', refX);
    marker.setAttribute('refY', refY);
    S.findDefs().appendChild(marker);

    return marker;
  }

  function convertline (elem) {
    // this routine came from the connectors extension
    // it is needed because midpoint markers don't work with line elements
    if (!(elem.tagName === 'line')) { return elem; }

    // Convert to polyline to accept mid-arrow

    const x1 = Number(elem.getAttribute('x1'));
    const x2 = Number(elem.getAttribute('x2'));
    const y1 = Number(elem.getAttribute('y1'));
    const y2 = Number(elem.getAttribute('y2'));
    const {id} = elem;

    const midPt = (' ' + ((x1 + x2) / 2) + ',' + ((y1 + y2) / 2) + ' ');
    const pline = addElem({
      element: 'polyline',
      attr: {
        points: (x1 + ',' + y1 + midPt + x2 + ',' + y2),
        stroke: elem.getAttribute('stroke'),
        'stroke-width': elem.getAttribute('stroke-width'),
        fill: 'none',
        opacity: elem.getAttribute('opacity') || 1
      }
    });
    $.each(mtypes, function (i, pos) { // get any existing marker definitions
      const nam = 'marker-' + pos;
      const m = elem.getAttribute(nam);
      if (m) { pline.setAttribute(nam, elem.getAttribute(nam)); }
    });

    const batchCmd = new S.BatchCommand();
    batchCmd.addSubCommand(new S.RemoveElementCommand(elem, elem.parentNode));
    batchCmd.addSubCommand(new S.InsertElementCommand(pline));

    $(elem).after(pline).remove();
    svgCanvas.clearSelection();
    pline.id = id;
    svgCanvas.addToSelection([pline]);
    S.addCommandToHistory(batchCmd);
    return pline;
  }

  function setMarker () {
    const poslist = {start_marker: 'start', mid_marker: 'mid', end_marker: 'end'};
    const pos = poslist[this.id];
    const markerName = 'marker-' + pos;
    let el = selElems[0];
    const marker = getLinked(el, markerName);
    if (marker) { $(marker).remove(); }
    el.removeAttribute(markerName);
    let val = this.value;
    if (val === '') { val = '\\nomarker'; }
    if (val === '\\nomarker') {
      setIcon(pos, val);
      S.call('changed', selElems);
      return;
    }
    // Set marker on element
    const id = markerPrefix + pos + '_' + el.id;
    addMarker(id, val);
    svgCanvas.changeSelectedAttribute(markerName, 'url(#' + id + ')');
    if (el.tagName === 'line' && pos === 'mid') { el = convertline(el); }
    S.call('changed', selElems);
    setIcon(pos, val);
  }

  // called when the main system modifies an object
  // this routine changes the associated markers to be the same color
  function colorChanged (elem) {
    const color = elem.getAttribute('stroke');

    $.each(mtypes, function (i, pos) {
      const marker = getLinked(elem, 'marker-' + pos);
      if (!marker) { return; }
      if (!marker.attributes.se_type) { return; } // not created by this extension
      const ch = marker.lastElementChild;
      if (!ch) { return; }
      const curfill = ch.getAttribute('fill');
      const curstroke = ch.getAttribute('stroke');
      if (curfill && curfill !== 'none') { ch.setAttribute('fill', color); }
      if (curstroke && curstroke !== 'none') { ch.setAttribute('stroke', color); }
    });
  }

  // called when the main system creates or modifies an object
  // primary purpose is create new markers for cloned objects
  function updateReferences (el) {
    $.each(mtypes, function (i, pos) {
      const id = markerPrefix + pos + '_' + el.id;
      const markerName = 'marker-' + pos;
      const marker = getLinked(el, markerName);
      if (!marker || !marker.attributes.se_type) { return; } // not created by this extension
      const url = el.getAttribute(markerName);
      if (url) {
        const len = el.id.length;
        const linkid = url.substr(-len - 1, len);
        if (el.id !== linkid) {
          const val = $('#' + pos + '_marker').attr('value');
          addMarker(id, val);
          svgCanvas.changeSelectedAttribute(markerName, 'url(#' + id + ')');
          if (el.tagName === 'line' && pos === 'mid') { el = convertline(el); }
          S.call('changed', selElems);
        }
      }
    });
  }

  // simulate a change event a text box that stores the current element's marker type
  function triggerTextEntry (pos, val) {
    $('#' + pos + '_marker').val(val);
    $('#' + pos + '_marker').change();
    // const txtbox = $('#'+pos+'_marker');
    // if (val.substr(0,1)=='\\') {txtbox.hide();}
    // else {txtbox.show();}
  }

  function showTextPrompt (pos) {
    let def = $('#' + pos + '_marker').val();
    if (def.substr(0, 1) === '\\') { def = ''; }
    $.prompt('Enter text for ' + pos + ' marker', def, function (txt) {
      if (txt) { triggerTextEntry(pos, txt); }
    });
  }

  /*
  function setMarkerSet(obj) {
    const parts = this.id.split('_');
    const set = parts[2];
    switch (set) {
    case 'off':
      triggerTextEntry('start','\\nomarker');
      triggerTextEntry('mid','\\nomarker');
      triggerTextEntry('end','\\nomarker');
      break;
    case 'dimension':
      triggerTextEntry('start','\\leftarrow');
      triggerTextEntry('end','\\rightarrow');
      showTextPrompt('mid');
      break;
    case 'label':
      triggerTextEntry('mid','\\nomarker');
      triggerTextEntry('end','\\rightarrow');
      showTextPrompt('start');
      break;
    }
  }
  */
  // callback function for a toolbar button click
  function setArrowFromButton (obj) {
    const parts = this.id.split('_');
    const pos = parts[1];
    let val = parts[2];
    if (parts[3]) { val += '_' + parts[3]; }

    if (val !== 'textmarker') {
      triggerTextEntry(pos, '\\' + val);
    } else {
      showTextPrompt(pos);
    }
  }

  function getTitle (lang = 'en', id) {
    const list = langList[lang];
    for (const i in list) {
      if (list.hasOwnProperty(i) && list[i].id === id) {
        return list[i].title;
      }
    }
    return id;
  }

  // build the toolbar button array from the marker definitions
  function buildButtonList (lang) {
    const buttons = [];
    // const i = 0;
    /*
    buttons.push({
      id: idPrefix + 'markers_off',
      title: 'Turn off all markers',
      type: 'context',
      events: { click: setMarkerSet },
      panel: 'marker_panel'
    });
    buttons.push({
      id: idPrefix + 'markers_dimension',
      title: 'Dimension',
      type: 'context',
      events: { click: setMarkerSet },
      panel: 'marker_panel'
    });
    buttons.push({
      id: idPrefix + 'markers_label',
      title: 'Label',
      type: 'context',
      events: { click: setMarkerSet },
      panel: 'marker_panel'
    });
*/
    $.each(mtypes, function (k, pos) {
      const listname = pos + '_marker_list';
      let def = true;
      $.each(markerTypes, function (id, v) {
        const title = getTitle(lang, String(id));
        buttons.push({
          id: idPrefix + pos + '_' + id,
          svgicon: id,
          title,
          type: 'context',
          events: {click: setArrowFromButton},
          panel: 'marker_panel',
          list: listname,
          isDefault: def
        });
        def = false;
      });
    });
    return buttons;
  }

  let currentLang;
  const ret = {
    name: 'Markers',
    svgicons: svgEditor.curConfig.extIconsPath + 'markers-icons.xml',
    callback () {
      $('#marker_panel').addClass('toolset').hide();
    },
    addLangData (lang) {
      currentLang = lang;
      return { data: langList[lang] };
    },
    selectedChanged (opts) {
      // Use this to update the current selected elements
      // console.log('selectChanged',opts);
      selElems = opts.elems;

      const markerElems = ['line', 'path', 'polyline', 'polygon'];

      let i = selElems.length;
      while (i--) {
        const elem = selElems[i];
        if (elem && markerElems.includes(elem.tagName)) {
          if (opts.selectedElement && !opts.multiselected) {
            showPanel(true);
          } else {
            showPanel(false);
          }
        } else {
          showPanel(false);
        }
      }
    },

    elementChanged (opts) {
      // console.log('elementChanged',opts);
      const elem = opts.elems[0];
      if (elem && (
        elem.getAttribute('marker-start') ||
        elem.getAttribute('marker-mid') ||
        elem.getAttribute('marker-end')
      )) {
        colorChanged(elem);
        updateReferences(elem);
      }
      // changing_flag = false; // Not apparently in use
    }
  };
  // Todo: Check if the lang will be available in time
  Object.defineProperties(ret, {
    buttons: {
      get () {
        return buildButtonList(currentLang);
      }
    },
    context_tools: {
      get () {
        return [
          {
            type: 'input',
            panel: 'marker_panel',
            title: 'Start marker',
            id: 'start_marker',
            label: 's',
            size: 3,
            events: { change: setMarker }
          }, {
            type: 'button-select',
            panel: 'marker_panel',
            title: getTitle(currentLang, 'start_marker_list'),
            id: 'start_marker_list',
            colnum: 3,
            events: { change: setArrowFromButton }
          }, {
            type: 'input',
            panel: 'marker_panel',
            title: 'Middle marker',
            id: 'mid_marker',
            label: 'm',
            defval: '',
            size: 3,
            events: { change: setMarker }
          }, {
            type: 'button-select',
            panel: 'marker_panel',
            title: getTitle(currentLang, 'mid_marker_list'),
            id: 'mid_marker_list',
            colnum: 3,
            events: { change: setArrowFromButton }
          }, {
            type: 'input',
            panel: 'marker_panel',
            title: 'End marker',
            id: 'end_marker',
            label: 'e',
            size: 3,
            events: { change: setMarker }
          }, {
            type: 'button-select',
            panel: 'marker_panel',
            title: getTitle(currentLang, 'end_marker_list'),
            id: 'end_marker_list',
            colnum: 3,
            events: { change: setArrowFromButton }
          }
        ];
      }
    }
  });
  return ret;
});