/* globals jQuery */
/*
 * ext-connector.js
 *
 * Licensed under the MIT License
 *
 * Copyright(c) 2010 Alexis Deveria
 *
 */

import svgEditor from '../svg-editor.js';
svgEditor.addExtension('Connector', function (S) {
  const $ = jQuery;
  const svgCanvas = svgEditor.canvas;
  const {svgroot, getNextId, getElem} = S,
    addElem = S.addSvgElementFromJson,
    selManager = S.selectorManager,
    connSel = '.se_connector',
    // connect_str = '-SE_CONNECT-',
    elData = $.data;

  let startX,
    startY,
    curLine,
    startElem,
    endElem,
    seNs,
    {svgcontent} = S,
    started = false,
    connections = [],
    selElems = [];

  const langList = {
    en: [
      {id: 'mode_connect', title: 'Connect two objects'}
    ],
    fr: [
      {id: 'mode_connect', title: 'Connecter deux objets'}
    ]
  };

  function getBBintersect (x, y, bb, offset) {
    if (offset) {
      offset -= 0;
      bb = $.extend({}, bb);
      bb.width += offset;
      bb.height += offset;
      bb.x -= offset / 2;
      bb.y -= offset / 2;
    }

    const midX = bb.x + bb.width / 2;
    const midY = bb.y + bb.height / 2;
    const lenX = x - midX;
    const lenY = y - midY;

    const slope = Math.abs(lenY / lenX);

    let ratio;
    if (slope < bb.height / bb.width) {
      ratio = (bb.width / 2) / Math.abs(lenX);
    } else {
      ratio = lenY
        ? (bb.height / 2) / Math.abs(lenY)
        : 0;
    }

    return {
      x: midX + lenX * ratio,
      y: midY + lenY * ratio
    };
  }

  function getOffset (side, line) {
    const giveOffset = !!line.getAttribute('marker-' + side);
    // const giveOffset = $(line).data(side+'_off');

    // TODO: Make this number (5) be based on marker width/height
    const size = line.getAttribute('stroke-width') * 5;
    return giveOffset ? size : 0;
  }

  function showPanel (on) {
    let connRules = $('#connector_rules');
    if (!connRules.length) {
      connRules = $('<style id="connector_rules"></style>').appendTo('head');
    }
    connRules.text(!on ? '' : '#tool_clone, #tool_topath, #tool_angle, #xy_panel { display: none !important; }');
    $('#connector_panel').toggle(on);
  }

  function setPoint (elem, pos, x, y, setMid) {
    const pts = elem.points;
    const pt = svgroot.createSVGPoint();
    pt.x = x;
    pt.y = y;
    if (pos === 'end') { pos = pts.numberOfItems - 1; }
    // TODO: Test for this on init, then use alt only if needed
    try {
      pts.replaceItem(pt, pos);
    } catch (err) {
      // Should only occur in FF which formats points attr as "n,n n,n", so just split
      const ptArr = elem.getAttribute('points').split(' ');
      for (let i = 0; i < ptArr.length; i++) {
        if (i === pos) {
          ptArr[i] = x + ',' + y;
        }
      }
      elem.setAttribute('points', ptArr.join(' '));
    }

    if (setMid) {
      // Add center point
      const ptStart = pts.getItem(0);
      const ptEnd = pts.getItem(pts.numberOfItems - 1);
      setPoint(elem, 1, (ptEnd.x + ptStart.x) / 2, (ptEnd.y + ptStart.y) / 2);
    }
  }

  function updateLine (diffX, diffY) {
    // Update line with element
    let i = connections.length;
    while (i--) {
      const conn = connections[i];
      const line = conn.connector;
      // const {elem} = conn;

      const pre = conn.is_start ? 'start' : 'end';
      // const sw = line.getAttribute('stroke-width') * 5;

      // Update bbox for this element
      const bb = elData(line, pre + '_bb');
      bb.x = conn.start_x + diffX;
      bb.y = conn.start_y + diffY;
      elData(line, pre + '_bb', bb);

      const altPre = conn.is_start ? 'end' : 'start';

      // Get center pt of connected element
      const bb2 = elData(line, altPre + '_bb');
      const srcX = bb2.x + bb2.width / 2;
      const srcY = bb2.y + bb2.height / 2;

      // Set point of element being moved
      const pt = getBBintersect(srcX, srcY, bb, getOffset(pre, line)); // $(line).data(pre+'_off')?sw:0
      setPoint(line, conn.is_start ? 0 : 'end', pt.x, pt.y, true);

      // Set point of connected element
      const pt2 = getBBintersect(pt.x, pt.y, elData(line, altPre + '_bb'), getOffset(altPre, line));
      setPoint(line, conn.is_start ? 'end' : 0, pt2.x, pt2.y, true);
    }
  }

  /**
  *
  * @param {array} [elem=selElems] Array of elements
  */
  function findConnectors (elems = selElems) {
    const connectors = $(svgcontent).find(connSel);
    connections = [];

    // Loop through connectors to see if one is connected to the element
    connectors.each(function () {
      let addThis;
      function add () {
        if (elems.includes(this)) {
          // Pretend this element is selected
          addThis = true;
        }
      }

      // Grab the ends
      const parts = [];
      ['start', 'end'].forEach(function (pos, i) {
        const key = 'c_' + pos;
        let part = elData(this, key);
        if (part == null) {
          part = document.getElementById(
            this.attributes['se:connector'].value.split(' ')[i]
          );
          elData(this, 'c_' + pos, part.id);
          elData(this, pos + '_bb', svgCanvas.getStrokedBBox([part]));
        } else part = document.getElementById(part);
        parts.push(part);
      }.bind(this));

      for (let i = 0; i < 2; i++) {
        const cElem = parts[i];

        addThis = false;
        // The connected element might be part of a selected group
        $(cElem).parents().each(add);

        if (!cElem || !cElem.parentNode) {
          $(this).remove();
          continue;
        }
        if (elems.includes(cElem) || addThis) {
          const bb = svgCanvas.getStrokedBBox([cElem]);
          connections.push({
            elem: cElem,
            connector: this,
            is_start: (i === 0),
            start_x: bb.x,
            start_y: bb.y
          });
        }
      }
    });
  }

  function updateConnectors (elems) {
    // Updates connector lines based on selected elements
    // Is not used on mousemove, as it runs getStrokedBBox every time,
    // which isn't necessary there.
    findConnectors(elems);
    if (connections.length) {
      // Update line with element
      let i = connections.length;
      while (i--) {
        const conn = connections[i];
        const line = conn.connector;
        const {elem} = conn;

        // const sw = line.getAttribute('stroke-width') * 5;
        const pre = conn.is_start ? 'start' : 'end';

        // Update bbox for this element
        const bb = svgCanvas.getStrokedBBox([elem]);
        bb.x = conn.start_x;
        bb.y = conn.start_y;
        elData(line, pre + '_bb', bb);
        /* const addOffset = */ elData(line, pre + '_off');

        const altPre = conn.is_start ? 'end' : 'start';

        // Get center pt of connected element
        const bb2 = elData(line, altPre + '_bb');
        const srcX = bb2.x + bb2.width / 2;
        const srcY = bb2.y + bb2.height / 2;

        // Set point of element being moved
        let pt = getBBintersect(srcX, srcY, bb, getOffset(pre, line));
        setPoint(line, conn.is_start ? 0 : 'end', pt.x, pt.y, true);

        // Set point of connected element
        const pt2 = getBBintersect(pt.x, pt.y, elData(line, altPre + '_bb'), getOffset(altPre, line));
        setPoint(line, conn.is_start ? 'end' : 0, pt2.x, pt2.y, true);

        // Update points attribute manually for webkit
        if (navigator.userAgent.includes('AppleWebKit')) {
          const pts = line.points;
          const len = pts.numberOfItems;
          const ptArr = [];
          for (let j = 0; j < len; j++) {
            pt = pts.getItem(j);
            ptArr[j] = pt.x + ',' + pt.y;
          }
          line.setAttribute('points', ptArr.join(' '));
        }
      }
    }
  }

  // Do once
  (function () {
    const gse = svgCanvas.groupSelectedElements;

    svgCanvas.groupSelectedElements = function () {
      svgCanvas.removeFromSelection($(connSel).toArray());
      return gse.apply(this, arguments);
    };

    const mse = svgCanvas.moveSelectedElements;

    svgCanvas.moveSelectedElements = function () {
      const cmd = mse.apply(this, arguments);
      updateConnectors();
      return cmd;
    };

    seNs = svgCanvas.getEditorNS();
  }());

  // Do on reset
  function init () {
    // Make sure all connectors have data set
    $(svgcontent).find('*').each(function () {
      const conn = this.getAttributeNS(seNs, 'connector');
      if (conn) {
        this.setAttribute('class', connSel.substr(1));
        const connData = conn.split(' ');
        const sbb = svgCanvas.getStrokedBBox([getElem(connData[0])]);
        const ebb = svgCanvas.getStrokedBBox([getElem(connData[1])]);
        $(this).data('c_start', connData[0])
          .data('c_end', connData[1])
          .data('start_bb', sbb)
          .data('end_bb', ebb);
        svgCanvas.getEditorNS(true);
      }
    });
    // updateConnectors();
  }

  // $(svgroot).parent().mousemove(function (e) {
  // // if (started
  // //   || svgCanvas.getMode() !== 'connector'
  // //  || e.target.parentNode.parentNode !== svgcontent) return;
  //
  // console.log('y')
  // // if (e.target.parentNode.parentNode === svgcontent) {
  // //
  // // }
  // });

  return {
    name: 'Connector',
    svgicons: svgEditor.curConfig.imgPath + 'conn.svg',
    buttons: [{
      id: 'mode_connect',
      type: 'mode',
      icon: svgEditor.curConfig.imgPath + 'cut.png',
      title: 'Connect two objects',
      includeWith: {
        button: '#tool_line',
        isDefault: false,
        position: 1
      },
      events: {
        click () {
          svgCanvas.setMode('connector');
        }
      }
    }],
    addLangData (lang) {
      return {
        data: langList[lang]
      };
    },
    mouseDown (opts) {
      const e = opts.event;
      startX = opts.start_x;
      startY = opts.start_y;
      const mode = svgCanvas.getMode();
      const {curConfig: {initStroke}} = svgEditor;

      if (mode === 'connector') {
        if (started) { return; }

        const mouseTarget = e.target;

        const parents = $(mouseTarget).parents();

        if ($.inArray(svgcontent, parents) !== -1) {
          // Connectable element

          // If child of foreignObject, use parent
          const fo = $(mouseTarget).closest('foreignObject');
          startElem = fo.length ? fo[0] : mouseTarget;

          // Get center of source element
          const bb = svgCanvas.getStrokedBBox([startElem]);
          const x = bb.x + bb.width / 2;
          const y = bb.y + bb.height / 2;

          started = true;
          curLine = addElem({
            element: 'polyline',
            attr: {
              id: getNextId(),
              points: (x + ',' + y + ' ' + x + ',' + y + ' ' + startX + ',' + startY),
              stroke: '#' + initStroke.color,
              'stroke-width': (!startElem.stroke_width || startElem.stroke_width === 0)
                ? initStroke.width
                : startElem.stroke_width,
              fill: 'none',
              opacity: initStroke.opacity,
              style: 'pointer-events:none'
            }
          });
          elData(curLine, 'start_bb', bb);
        }
        return {
          started: true
        };
      }
      if (mode === 'select') {
        findConnectors();
      }
    },
    mouseMove (opts) {
      const zoom = svgCanvas.getZoom();
      // const e = opts.event;
      const x = opts.mouse_x / zoom;
      const y = opts.mouse_y / zoom;

      const diffX = x - startX,
        diffY = y - startY;

      const mode = svgCanvas.getMode();

      if (mode === 'connector' && started) {
        // const sw = curLine.getAttribute('stroke-width') * 3;
        // Set start point (adjusts based on bb)
        const pt = getBBintersect(x, y, elData(curLine, 'start_bb'), getOffset('start', curLine));
        startX = pt.x;
        startY = pt.y;

        setPoint(curLine, 0, pt.x, pt.y, true);

        // Set end point
        setPoint(curLine, 'end', x, y, true);
      } else if (mode === 'select') {
        let slen = selElems.length;
        while (slen--) {
          const elem = selElems[slen];
          // Look for selected connector elements
          if (elem && elData(elem, 'c_start')) {
            // Remove the "translate" transform given to move
            svgCanvas.removeFromSelection([elem]);
            svgCanvas.getTransformList(elem).clear();
          }
        }
        if (connections.length) {
          updateLine(diffX, diffY);
        }
      }
    },
    mouseUp (opts) {
      // const zoom = svgCanvas.getZoom();
      const e = opts.event;
      // , x = opts.mouse_x / zoom,
      // , y = opts.mouse_y / zoom,
      let mouseTarget = e.target;

      if (svgCanvas.getMode() === 'connector') {
        const fo = $(mouseTarget).closest('foreignObject');
        if (fo.length) { mouseTarget = fo[0]; }

        const parents = $(mouseTarget).parents();

        if (mouseTarget === startElem) {
          // Start line through click
          started = true;
          return {
            keep: true,
            element: null,
            started
          };
        }
        if ($.inArray(svgcontent, parents) === -1) {
          // Not a valid target element, so remove line
          $(curLine).remove();
          started = false;
          return {
            keep: false,
            element: null,
            started
          };
        }
        // Valid end element
        endElem = mouseTarget;

        const startId = startElem.id, endId = endElem.id;
        const connStr = startId + ' ' + endId;
        const altStr = endId + ' ' + startId;
        // Don't create connector if one already exists
        const dupe = $(svgcontent).find(connSel).filter(function () {
          const conn = this.getAttributeNS(seNs, 'connector');
          if (conn === connStr || conn === altStr) { return true; }
        });
        if (dupe.length) {
          $(curLine).remove();
          return {
            keep: false,
            element: null,
            started: false
          };
        }

        const bb = svgCanvas.getStrokedBBox([endElem]);

        const pt = getBBintersect(startX, startY, bb, getOffset('start', curLine));
        setPoint(curLine, 'end', pt.x, pt.y, true);
        $(curLine)
          .data('c_start', startId)
          .data('c_end', endId)
          .data('end_bb', bb);
        seNs = svgCanvas.getEditorNS(true);
        curLine.setAttributeNS(seNs, 'se:connector', connStr);
        curLine.setAttribute('class', connSel.substr(1));
        curLine.setAttribute('opacity', 1);
        svgCanvas.addToSelection([curLine]);
        svgCanvas.moveToBottomSelectedElement();
        selManager.requestSelector(curLine).showGrips(false);
        started = false;
        return {
          keep: true,
          element: curLine,
          started
        };
      }
    },
    selectedChanged (opts) {
      // TODO: Find better way to skip operations if no connectors are in use
      if (!$(svgcontent).find(connSel).length) { return; }

      if (svgCanvas.getMode() === 'connector') {
        svgCanvas.setMode('select');
      }

      // Use this to update the current selected elements
      selElems = opts.elems;

      let i = selElems.length;
      while (i--) {
        const elem = selElems[i];
        if (elem && elData(elem, 'c_start')) {
          selManager.requestSelector(elem).showGrips(false);
          if (opts.selectedElement && !opts.multiselected) {
            // TODO: Set up context tools and hide most regular line tools
            showPanel(true);
          } else {
            showPanel(false);
          }
        } else {
          showPanel(false);
        }
      }
      updateConnectors();
    },
    elementChanged (opts) {
      let elem = opts.elems[0];
      if (elem && elem.tagName === 'svg' && elem.id === 'svgcontent') {
        // Update svgcontent (can change on import)
        svgcontent = elem;
        init();
      }

      // Has marker, so change offset
      if (elem && (
        elem.getAttribute('marker-start') ||
        elem.getAttribute('marker-mid') ||
        elem.getAttribute('marker-end')
      )) {
        const start = elem.getAttribute('marker-start');
        const mid = elem.getAttribute('marker-mid');
        const end = elem.getAttribute('marker-end');
        curLine = elem;
        $(elem)
          .data('start_off', !!start)
          .data('end_off', !!end);

        if (elem.tagName === 'line' && mid) {
          // 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'),
              'marker-mid': mid,
              fill: 'none',
              opacity: elem.getAttribute('opacity') || 1
            }
          });
          $(elem).after(pline).remove();
          svgCanvas.clearSelection();
          pline.id = id;
          svgCanvas.addToSelection([pline]);
          elem = pline;
        }
      }
      // Update line if it's a connector
      if (elem.getAttribute('class') === connSel.substr(1)) {
        const start = getElem(elData(elem, 'c_start'));
        updateConnectors([start]);
      } else {
        updateConnectors();
      }
    },
    IDsUpdated (input) {
      const remove = [];
      input.elems.forEach(function (elem) {
        if ('se:connector' in elem.attr) {
          elem.attr['se:connector'] = elem.attr['se:connector'].split(' ')
            .map(function (oldID) { return input.changes[oldID]; }).join(' ');

          // Check validity - the field would be something like 'svg_21 svg_22', but
          // if one end is missing, it would be 'svg_21' and therefore fail this test
          if (!/. ./.test(elem.attr['se:connector'])) {
            remove.push(elem.attr.id);
          }
        }
      });
      return {remove};
    },
    toolButtonStateUpdate (opts) {
      if (opts.nostroke) {
        if ($('#mode_connect').hasClass('tool_button_current')) {
          svgEditor.clickSelect();
        }
      }
      $('#mode_connect')
        .toggleClass('disabled', opts.nostroke);
    }
  };
});