/**
  The implementation of the postprocessing part that applies CoSE layout over the spectral layout
*/

const aux = require('./auxiliary');
const CoSELayout = require('cose-base').CoSELayout;
const CoSENode = require('cose-base').CoSENode;
const PointD = require('cose-base').layoutBase.PointD;
const DimensionD = require('cose-base').layoutBase.DimensionD;
const LayoutConstants = require('cose-base').layoutBase.LayoutConstants;
const FDLayoutConstants = require('cose-base').layoutBase.FDLayoutConstants;
const CoSEConstants = require('cose-base').CoSEConstants;

// main function that cose layout is processed
let coseLayout = function(options, spectralResult){

  let cy = options.cy;
  let eles = options.eles;
  let nodes = eles.nodes();
  let edges = eles.edges();
  
  let nodeIndexes;
  let xCoords;
  let yCoords;
  let idToLNode =  {};  
  
  if(options.randomize){
    nodeIndexes = spectralResult["nodeIndexes"];
    xCoords = spectralResult["xCoords"];
    yCoords = spectralResult["yCoords"];
  }

  const isFn = fn => typeof fn === 'function';
  
  const optFn = ( opt, ele ) => {
    if( isFn( opt ) ){
      return opt( ele );
    } else {
      return opt;
    }
  };  

  /**** Postprocessing functions ****/

  let parentsWithoutChildren = aux.calcParentsWithoutChildren(cy, eles);

  // transfer cytoscape nodes to cose nodes
  let processChildrenList = function (parent, children, layout, options) {
    let size = children.length;
    for (let i = 0; i < size; i++) {
      let theChild = children[i];
      let children_of_children = null;
      if(theChild.intersection(parentsWithoutChildren).length == 0) {
        children_of_children = theChild.children();
      }
      let theNode;    

      let dimensions = theChild.layoutDimensions({
        nodeDimensionsIncludeLabels: options.nodeDimensionsIncludeLabels
      });

      if (theChild.outerWidth() != null
              && theChild.outerHeight() != null) {
        if(options.randomize){
          if(!theChild.isParent()){
            theNode = parent.add(new CoSENode(layout.graphManager,
                    new PointD(xCoords[nodeIndexes.get(theChild.id())] - dimensions.w / 2, yCoords[nodeIndexes.get(theChild.id())] - dimensions.h / 2),
                    new DimensionD(parseFloat(dimensions.w), parseFloat(dimensions.h))));
          }
          else{
            let parentInfo = aux.calcBoundingBox(theChild, xCoords, yCoords, nodeIndexes);
            if(theChild.intersection(parentsWithoutChildren).length == 0) {
              theNode = parent.add(new CoSENode(layout.graphManager,
                new PointD(parentInfo.topLeftX, parentInfo.topLeftY),
                new DimensionD(parentInfo.width, parentInfo.height)));
            }
            else {  // for the parentsWithoutChildren
              theNode = parent.add(new CoSENode(layout.graphManager,
                new PointD(parentInfo.topLeftX, parentInfo.topLeftY),
                new DimensionD(parseFloat(dimensions.w), parseFloat(dimensions.h))));
            }
          }
        }
        else{
          theNode = parent.add(new CoSENode(layout.graphManager,
                  new PointD(theChild.position('x') - dimensions.w / 2, theChild.position('y') - dimensions.h / 2),
                  new DimensionD(parseFloat(dimensions.w), parseFloat(dimensions.h))));        
        }
      }
      else {
        theNode = parent.add(new CoSENode(this.graphManager));
      }
      // Attach id to the layout node and repulsion value
      theNode.id = theChild.data("id");
      theNode.nodeRepulsion = optFn( options.nodeRepulsion, theChild );
      // Attach the paddings of cy node to layout node
      theNode.paddingLeft = parseInt( theChild.css('padding') );
      theNode.paddingTop = parseInt( theChild.css('padding') );
      theNode.paddingRight = parseInt( theChild.css('padding') );
      theNode.paddingBottom = parseInt( theChild.css('padding') );

      //Attach the label properties to both compound and simple nodes if labels will be included in node dimensions
      //These properties will be used while updating bounds of compounds during iterations or tiling
      //and will be used for simple nodes while transferring final positions to cytoscape
      if(options.nodeDimensionsIncludeLabels){
        theNode.labelWidth = theChild.boundingBox({ includeLabels: true, includeNodes: false, includeOverlays: false }).w;
        theNode.labelHeight = theChild.boundingBox({ includeLabels: true, includeNodes: false, includeOverlays: false }).h;
        theNode.labelPosVertical = theChild.css("text-valign");
        theNode.labelPosHorizontal = theChild.css("text-halign");
      }

      // Map the layout node
      idToLNode[theChild.data("id")] = theNode;

      if (isNaN(theNode.rect.x)) {
        theNode.rect.x = 0;
      }

      if (isNaN(theNode.rect.y)) {
        theNode.rect.y = 0;
      }

      if (children_of_children != null && children_of_children.length > 0) {
        let theNewGraph;
        theNewGraph = layout.getGraphManager().add(layout.newGraph(), theNode);
        processChildrenList(theNewGraph, children_of_children, layout, options);
      }
    }
  };   

  // transfer cytoscape edges to cose edges
  let processEdges = function(layout, gm, edges){
    let idealLengthTotal = 0;
    let edgeCount = 0;
    for (let i = 0; i < edges.length; i++) {
      let edge = edges[i];
      let sourceNode = idToLNode[edge.data("source")];
      let targetNode = idToLNode[edge.data("target")];
      if(sourceNode && targetNode && sourceNode !== targetNode && sourceNode.getEdgesBetween(targetNode).length == 0){
        let e1 = gm.add(layout.newEdge(), sourceNode, targetNode);
        e1.id = edge.id();
        e1.idealLength = optFn( options.idealEdgeLength, edge );
        e1.edgeElasticity = optFn( options.edgeElasticity, edge );        
        idealLengthTotal += e1.idealLength;
        edgeCount++;
      }
    }
    // we need to update the ideal edge length constant with the avg. ideal length value after processing edges
    // in case there is no edge, use other options
    if (options.idealEdgeLength != null){
      if (edgeCount > 0)
        CoSEConstants.DEFAULT_EDGE_LENGTH = FDLayoutConstants.DEFAULT_EDGE_LENGTH = idealLengthTotal / edgeCount;
      else if(!isFn(options.idealEdgeLength)) // in case there is no edge, but option gives a value to use
        CoSEConstants.DEFAULT_EDGE_LENGTH = FDLayoutConstants.DEFAULT_EDGE_LENGTH = options.idealEdgeLength;
      else  // in case there is no edge and we cannot get a value from option (because it's a function)
        CoSEConstants.DEFAULT_EDGE_LENGTH = FDLayoutConstants.DEFAULT_EDGE_LENGTH = 50;
      // we need to update these constant values based on the ideal edge length constant
      CoSEConstants.MIN_REPULSION_DIST = FDLayoutConstants.MIN_REPULSION_DIST = FDLayoutConstants.DEFAULT_EDGE_LENGTH / 10.0;
      CoSEConstants.DEFAULT_RADIAL_SEPARATION = FDLayoutConstants.DEFAULT_EDGE_LENGTH;
    }
  }; 
  
  // transfer cytoscape constraints to cose layout
  let processConstraints = function(layout, options){
    // get nodes to be fixed
    if(options.fixedNodeConstraint){
      layout.constraints["fixedNodeConstraint"] = options.fixedNodeConstraint;
    }
    // get nodes to be aligned
    if(options.alignmentConstraint){
      layout.constraints["alignmentConstraint"] = options.alignmentConstraint;
    }
    // get nodes to be relatively placed
    if(options.relativePlacementConstraint){
      layout.constraints["relativePlacementConstraint"] = options.relativePlacementConstraint;
    }  
  };
  
  /**** Apply postprocessing ****/
  if (options.nestingFactor != null)
    CoSEConstants.PER_LEVEL_IDEAL_EDGE_LENGTH_FACTOR = FDLayoutConstants.PER_LEVEL_IDEAL_EDGE_LENGTH_FACTOR = options.nestingFactor;
  if (options.gravity != null)
    CoSEConstants.DEFAULT_GRAVITY_STRENGTH = FDLayoutConstants.DEFAULT_GRAVITY_STRENGTH = options.gravity;
  if (options.numIter != null)
    CoSEConstants.MAX_ITERATIONS = FDLayoutConstants.MAX_ITERATIONS = options.numIter;
  if (options.gravityRange != null)
    CoSEConstants.DEFAULT_GRAVITY_RANGE_FACTOR = FDLayoutConstants.DEFAULT_GRAVITY_RANGE_FACTOR = options.gravityRange;
  if(options.gravityCompound != null)
    CoSEConstants.DEFAULT_COMPOUND_GRAVITY_STRENGTH = FDLayoutConstants.DEFAULT_COMPOUND_GRAVITY_STRENGTH = options.gravityCompound;
  if(options.gravityRangeCompound != null)
    CoSEConstants.DEFAULT_COMPOUND_GRAVITY_RANGE_FACTOR = FDLayoutConstants.DEFAULT_COMPOUND_GRAVITY_RANGE_FACTOR = options.gravityRangeCompound;
  if (options.initialEnergyOnIncremental != null)
    CoSEConstants.DEFAULT_COOLING_FACTOR_INCREMENTAL = FDLayoutConstants.DEFAULT_COOLING_FACTOR_INCREMENTAL = options.initialEnergyOnIncremental;
  
  if (options.tilingCompareBy != null)
    CoSEConstants.TILING_COMPARE_BY = options.tilingCompareBy;

  if(options.quality == 'proof')
    LayoutConstants.QUALITY = 2;
  else
    LayoutConstants.QUALITY = 0;    

  CoSEConstants.NODE_DIMENSIONS_INCLUDE_LABELS = FDLayoutConstants.NODE_DIMENSIONS_INCLUDE_LABELS = LayoutConstants.NODE_DIMENSIONS_INCLUDE_LABELS = options.nodeDimensionsIncludeLabels;
  CoSEConstants.DEFAULT_INCREMENTAL = FDLayoutConstants.DEFAULT_INCREMENTAL = LayoutConstants.DEFAULT_INCREMENTAL =
          !(options.randomize);
  CoSEConstants.ANIMATE = FDLayoutConstants.ANIMATE = LayoutConstants.ANIMATE = options.animate;
  CoSEConstants.TILE = options.tile;
  CoSEConstants.TILING_PADDING_VERTICAL = 
          typeof options.tilingPaddingVertical === 'function' ? options.tilingPaddingVertical.call() : options.tilingPaddingVertical;
  CoSEConstants.TILING_PADDING_HORIZONTAL = 
          typeof options.tilingPaddingHorizontal === 'function' ? options.tilingPaddingHorizontal.call() : options.tilingPaddingHorizontal;  

  CoSEConstants.DEFAULT_INCREMENTAL = FDLayoutConstants.DEFAULT_INCREMENTAL = LayoutConstants.DEFAULT_INCREMENTAL = true;
  CoSEConstants.PURE_INCREMENTAL = !options.randomize;
  LayoutConstants.DEFAULT_UNIFORM_LEAF_NODE_SIZES = options.uniformNodeDimensions;

  // This part is for debug/demo purpose
  if(options.step == "transformed"){
    CoSEConstants.TRANSFORM_ON_CONSTRAINT_HANDLING = true;
    CoSEConstants.ENFORCE_CONSTRAINTS = false;
    CoSEConstants.APPLY_LAYOUT = false;
  }
  if(options.step == "enforced"){
    CoSEConstants.TRANSFORM_ON_CONSTRAINT_HANDLING = false;
    CoSEConstants.ENFORCE_CONSTRAINTS = true;
    CoSEConstants.APPLY_LAYOUT = false;
  }
  if(options.step == "cose"){
    CoSEConstants.TRANSFORM_ON_CONSTRAINT_HANDLING = false;
    CoSEConstants.ENFORCE_CONSTRAINTS = false;
    CoSEConstants.APPLY_LAYOUT = true;
  }  
  if(options.step == "all"){
    if(options.randomize)
      CoSEConstants.TRANSFORM_ON_CONSTRAINT_HANDLING = true;
    else
      CoSEConstants.TRANSFORM_ON_CONSTRAINT_HANDLING = false;
    CoSEConstants.ENFORCE_CONSTRAINTS = true;
    CoSEConstants.APPLY_LAYOUT = true;
  }
  
  if(options.fixedNodeConstraint || options.alignmentConstraint || options.relativePlacementConstraint){
    CoSEConstants.TREE_REDUCTION_ON_INCREMENTAL = false;
  }
  else{
    CoSEConstants.TREE_REDUCTION_ON_INCREMENTAL = true;
  }

  let coseLayout = new CoSELayout();
  let gm = coseLayout.newGraphManager(); 

  processChildrenList(gm.addRoot(), aux.getTopMostNodes(nodes), coseLayout, options);
  processEdges(coseLayout, gm, edges);
  processConstraints(coseLayout, options);

  coseLayout.runLayout();
  
  return idToLNode;
};

module.exports = { coseLayout };