/**
* Utility class used for creating stacked series.
*
* @module charts
* @submodule charts-base
* @class StackingUtil
* @constructor
*/
function StackingUtil(){}
StackingUtil.prototype = {
/**
* Indicates whether the series is stacked.
*
* @property _stacked
* @private
*/
_stacked: true,
/**
* @protected
*
* Adjusts coordinate values for stacked series.
*
* @method _stackCoordinates
*/
_stackCoordinates: function()
{
if(this.get("direction") == "vertical")
{
this._stackXCoords();
}
else
{
this._stackYCoords();
}
},
/**
* Stacks coordinates for a stacked vertical series.
*
* @method _stackXCoords
* @protected
*/
_stackXCoords: function()
{
var order = this.get("order"),
type = this.get("type"),
graph = this.get("graph"),
seriesCollection = graph.seriesTypes[type],
i = 0,
xcoords = this.get("xcoords"),
ycoords = this.get("ycoords"),
len,
coord,
prevCoord,
prevOrder,
stackedXCoords = xcoords.concat(),
prevXCoords,
prevYCoords,
nullIndices = [],
nullIndex;
if(order > 0)
{
prevXCoords = seriesCollection[order - 1].get("stackedXCoords");
prevYCoords = seriesCollection[order - 1].get("stackedYCoords");
len = prevXCoords.length;
}
else
{
len = xcoords.length;
}
for(; i < len; i = i + 1)
{
if(Y_Lang.isNumber(xcoords[i]))
{
if(order > 0)
{
prevCoord = prevXCoords[i];
if(!Y_Lang.isNumber(prevCoord))
{
prevOrder = order;
while(prevOrder > - 1 && !Y_Lang.isNumber(prevCoord))
{
prevOrder = prevOrder - 1;
if(prevOrder > -1)
{
prevCoord = seriesCollection[prevOrder].get("stackedXCoords")[i];
}
else
{
prevCoord = this._leftOrigin;
}
}
}
xcoords[i] = xcoords[i] + prevCoord;
}
stackedXCoords[i] = xcoords[i];
}
else
{
nullIndices.push(i);
}
}
this._cleanXNaN(stackedXCoords, ycoords);
len = nullIndices.length;
if(len > 0)
{
for(i = 0; i < len; i = i + 1)
{
nullIndex = nullIndices[i];
coord = order > 0 ? prevXCoords[nullIndex] : this._leftOrigin;
stackedXCoords[nullIndex] = Math.max(stackedXCoords[nullIndex], coord);
}
}
this.set("stackedXCoords", stackedXCoords);
this.set("stackedYCoords", ycoords);
},
/**
* Stacks coordinates for a stacked horizontal series.
*
* @method _stackYCoords
* @protected
*/
_stackYCoords: function()
{
var order = this.get("order"),
type = this.get("type"),
graph = this.get("graph"),
h = graph.get("height"),
seriesCollection = graph.seriesTypes[type],
i = 0,
xcoords = this.get("xcoords"),
ycoords = this.get("ycoords"),
len,
coord,
prevCoord,
prevOrder,
stackedYCoords = ycoords.concat(),
prevXCoords,
prevYCoords,
nullIndices = [],
nullIndex;
if(order > 0)
{
prevXCoords = seriesCollection[order - 1].get("stackedXCoords");
prevYCoords = seriesCollection[order - 1].get("stackedYCoords");
len = prevYCoords.length;
}
else
{
len = ycoords.length;
}
for(; i < len; i = i + 1)
{
if(Y_Lang.isNumber(ycoords[i]))
{
if(order > 0)
{
prevCoord = prevYCoords[i];
if(!Y_Lang.isNumber(prevCoord))
{
prevOrder = order;
while(prevOrder > - 1 && !Y_Lang.isNumber(prevCoord))
{
prevOrder = prevOrder - 1;
if(prevOrder > -1)
{
prevCoord = seriesCollection[prevOrder].get("stackedYCoords")[i];
}
else
{
prevCoord = this._bottomOrigin;
}
}
}
ycoords[i] = prevCoord - (h - ycoords[i]);
}
stackedYCoords[i] = ycoords[i];
}
else
{
nullIndices.push(i);
}
}
this._cleanYNaN(xcoords, stackedYCoords);
len = nullIndices.length;
if(len > 0)
{
for(i = 0; i < len; i = i + 1)
{
nullIndex = nullIndices[i];
coord = order > 0 ? prevYCoords[nullIndex] : h;
stackedYCoords[nullIndex] = Math.min(stackedYCoords[nullIndex], coord);
}
}
this.set("stackedXCoords", xcoords);
this.set("stackedYCoords", stackedYCoords);
},
/**
* Cleans invalid x-coordinates by calculating their value based on the corresponding y-coordinate, the
* previous valid x-coordinate with its corresponding y-coordinate and the next valid x-coordinate with
* its corresponding y-coordinate. If there is no previous or next valid x-coordinate, the value will not
* be altered.
*
* @method _cleanXNaN
* @param {Array} xcoords An array of x-coordinate values
* @param {Array} ycoords An arry of y-coordinate values
* @private
*/
_cleanXNaN: function(xcoords, ycoords)
{
var previousValidIndex,
nextValidIndex,
previousValidX,
previousValidY,
x,
y,
nextValidX,
nextValidY,
isNumber = Y_Lang.isNumber,
m,
i = 0,
len = ycoords.length;
for(; i < len; ++i)
{
x = xcoords[i];
y = ycoords[i];
//if x is invalid, calculate where it should be
if(!isNumber(x) && i > 0 && i < len - 1)
{
previousValidY = ycoords[i - 1];
//check to see if the previous value is valid
previousValidX = this._getPreviousValidCoordValue(xcoords, i);
nextValidY = ycoords[i + 1];
nextValidX = this._getNextValidCoordValue(xcoords, i);
//check to see if the next value is valid
if(isNumber(previousValidX) && isNumber(nextValidX))
{
//calculate slope and solve for x
m = (nextValidY - previousValidY) / (nextValidX - previousValidX);
xcoords[i] = (y + (m * previousValidX) - previousValidY)/m;
}
previousValidIndex = NaN;
nextValidIndex = NaN;
}
}
},
/**
* Returns the previous valid (numeric) value in an array if available.
*
* @method _getPreviousValidCoordValue
* @param {Array} coords Array of values
* @param {Number} index The index in the array in which to begin searching.
* @return Number
* @private
*/
_getPreviousValidCoordValue: function(coords, index)
{
var coord,
isNumber = Y_Lang.isNumber,
limit = -1;
while(!isNumber(coord) && index > limit)
{
index = index - 1;
coord = coords[index];
}
return coord;
},
/**
* Returns the next valid (numeric) value in an array if available.
*
* @method _getNextValidCoordValue
* @param {Array} coords Array of values
* @param {Number} index The index in the array in which to begin searching.
* @return Number
* @private
*/
_getNextValidCoordValue: function(coords, index)
{
var coord,
isNumber = Y_Lang.isNumber,
limit = coords.length;
while(!isNumber(coord) && index < limit)
{
index = index + 1;
coord = coords[index];
}
return coord;
},
/**
* Cleans invalid y-coordinates by calculating their value based on the corresponding x-coordinate, the
* previous valid y-coordinate with its corresponding x-coordinate and the next valid y-coordinate with
* its corresponding x-coordinate. If there is no previous or next valid y-coordinate, the value will not
* be altered.
*
* @method _cleanYNaN
* @param {Array} xcoords An array of x-coordinate values
* @param {Array} ycoords An arry of y-coordinate values
* @private
*/
_cleanYNaN: function(xcoords, ycoords)
{
var previousValidIndex,
nextValidIndex,
previousValidX,
previousValidY,
x,
y,
nextValidX,
nextValidY,
isNumber = Y_Lang.isNumber,
m,
i = 0,
len = xcoords.length;
for(; i < len; ++i)
{
x = xcoords[i];
y = ycoords[i];
//if y is invalid, calculate where it should be
if(!isNumber(y) && i > 0 && i < len - 1)
{
//check to see if the previous value is valid
previousValidX = xcoords[i - 1];
previousValidY = this._getPreviousValidCoordValue(ycoords, i);
//check to see if the next value is valid
nextValidX = xcoords[i + 1];
nextValidY = this._getNextValidCoordValue(ycoords, i);
if(isNumber(previousValidY) && isNumber(nextValidY))
{
//calculate slope and solve for y
m = (nextValidY - previousValidY) / (nextValidX - previousValidX);
ycoords[i] = previousValidY + ((m * x) - (m * previousValidX));
}
previousValidIndex = NaN;
nextValidIndex = NaN;
}
}
}
};
Y.StackingUtil = StackingUtil;
