/**
 * Convert a measurement to inches.
 * @param a measurement property e.g. "49.3mm"
 * @return the corresponding number of inches.
 */
function getInches(measurement) {
	var vUnits = measurement.substr(-2);
	var vValue = parseFloat(measurement.substr(0, measurement.length - 2));
	switch (vUnits) {
	case "mm":
		vValue = vValue * 0.0393700787;
		break;
	case "cm":
		vValue = vValue * 0.393700787;
		break;
	case "pt":
		vValue = vValue / 72;
	}
	return vValue;
}

/**
 * write a measurement in inches
 * @param the number of inches
 */
function formatInches(vValue) {
// Round a measurement value to the nearest 1000th of an inch
	return (Math.round(1000 * vValue) / 1000).toString() + "in";
}

/**
 * write a measurement in points
 * @param the number of inches
 */
function formatPoints(vValue) {
	vValue = vValue * 72;
// Round a measurement value to the nearest 10th of an point
	return (Math.round(10 * vValue) / 10).toString() + "pt";
}


// Combine a text draw and field into a field + caption


// Get the list of selected nodes
// for this function to execute we need a text draw and a caption-less field
var selection = designer.getSelection();
var validSelection = false;
var field = null;
var text = null;
if (selection.length == 2)
{
    for (var i=0; i<2; i++)
    {
		var vItem = selection.item(i);
        if (vItem.className === "field" && vItem.caption.value.oneOfChild.value.toString() == "") {
        	field = vItem;
		} else if (vItem.className == "draw" && 
			   (vItem.value.oneOfChild.className === "text" || vItem.value.oneOfChild.className === "exData")) {
        	text = vItem;
		}
    }

	if (field != null && text != null)
       validSelection = true;
}

if (validSelection)
{
	var bGrowableX = false;
	var bGrowableY = false;


	var tx = getInches(text.x);
    var tw = getInches(text.w);
    var fx = getInches(field.x);
    var fy = getInches(field.y);
    var fw = getInches(field.w);
	if (fw === 0) {
		fw = getInches(field.minW);
		bGrowableX = true;
	}

    var ty = getInches(text.y);
    var th = getInches(text.h);
    var fy = getInches(field.y);
    var fh = getInches(field.h);
	if (fh === 0) {
		fh = getInches(field.minH);
		bGrowableY = true;
	}

// Some checks for zero-dimension growable objects...
// accuracy of results will not be as good.
	if (tw === 0) {
		if (fx === 0) {
			tw = 1;
		} else {
			tw = (fx - tx) + fw;
		}
	}
	if (th === 0) {
		th = fy - ty;
	}
	if (fh === 0) {
		// field height is a wild guess
		fh = getInches(field.font.size) * 1.2 + getInches(field.margin.topInset) + getInches(field.margin.bottomInset);
	}
	if (fw === 0) {
		// zero width -- default to text width plus the field margins
		fw = tw + getInches(field.margin.leftInset) + getInches(field.margin.rightInset);
		fx = tx;
	}

	// Copy the caption value over.
	// special case for rich text
	if (text.value.oneOfChild.className === "exData") {
		field.caption.value.nodes.remove(field.caption.value.oneOfChild);
		field.caption.value.nodes.append(text.value.oneOfChild);
	} else {
	    field.caption.value.text = text.rawValue;
	}	

	// Assign all possible paragraph and font properties from the text object
	// to the field caption
	field.caption.reserve = formatInches(fy - ty);
	field.caption.placement = "top";
	field.caption.para.hAlign = text.para.hAlign;
	field.caption.para.lineHeight = text.para.lineHeight;
	field.caption.para.marginLeft = text.para.marginLeft;
	field.caption.para.marginRight = text.para.marginRight;
	field.caption.para.orphans = text.para.orphans;
	field.caption.para.preserve = text.para.preserve;
	field.caption.para.radixOffset = text.para.radixOffset;
	field.caption.para.spaceAbove = text.para.spaceAbove;
	field.caption.para.spaceBelow = text.para.spaceBelow;
	field.caption.para.tabDefault = text.para.tabDefault;
	field.caption.para.tabStops = text.para.tabStops;
	field.caption.para.textIndent = text.para.textIndent;
	field.caption.para.vAlign = text.para.vAlign;
	field.caption.para.widows = text.para.widows;
	field.caption.para.wordSpacingMaximum = text.para.wordSpacingMaximum;
	field.caption.para.wordSpacingMinimum = text.para.wordSpacingMinimum;
	field.caption.para.wordSpacingOptimum = text.para.wordSpacingOptimum;

	field.caption.font.baselineShift = text.font.baselineShift;
	field.caption.font.fontHorizontalScale = text.font.fontHorizontalScale;
	field.caption.font.fontVerticalScale = text.font.fontVerticalScale;
	field.caption.font.kerningMode = text.font.kerningMode;
	field.caption.font.letterSpacing = text.font.letterSpacing;
	field.caption.font.lineThrough = text.font.lineThrough;
	field.caption.font.lineThroughPeriod = text.font.lineThroughPeriod;
	field.caption.font.overline = text.font.overline;
	field.caption.font.overlinePeriod = text.font.overlinePeriod;
	field.caption.font.posture = text.font.posture;
	field.caption.font.size = text.font.size;
	field.caption.font.typeface = text.font.typeface;
	field.caption.font.underline = text.font.underline;
	field.caption.font.underlinePeriod = text.font.underlinePeriod;
	field.caption.font.weight = text.font.weight;
	
	// handle the case where the text starts to the right of the field. Needs to be indented (marginLeft)
	// to preserve the same starting location
	if (tx > fx) {
		field.caption.para.marginLeft = formatPoints(getInches(field.caption.para.marginLeft) + tx - fx);
	}
	
	// The text ends before the field does.  If the text is multi-line, 
	// making it wider will result in different wrapping.
	// Compensate by setting a right margin
	if ((tx + tw) < (fx + fw)) {
		field.caption.para.marginRight = formatPoints(getInches(field.caption.para.marginRight) + (fx + fw) - (tx + tw));
	}

	// The text ends after the field. We need to make the field wider to ensure that
	// there is room for the text. Set field right margin so that the field text area is constant
	if ((tx + tw) > (fx + fw)) {
		var delta = (tx + tw) - (fx + fw);
		field.w = formatInches(fw + delta);
		fw = fw + delta;
		field.para.marginRight = formatPoints(getInches(field.para.marginRight) + delta);
	}

	// The text starts to the left of the field. We need to make the field wider to ensure that
	// there is room for the text. Set field left margin so that the field text area is constant
	if (tx < fx) {
		var delta = fx - tx;
		field.w = formatInches(fw + delta);
		fw = fw + delta;
		field.x = formatInches(tx);
		fx = tx;
		field.para.marginLeft = formatPoints(getInches(field.para.marginLeft) + delta);
	}



	// if there is a gap between the text and the field, we want to preserve vertical positioning.
	// do this by setting paragraph spaceBelow to be the size of the gap.
	if ((ty + th) < fy) {
		field.caption.para.spaceBelow = formatPoints(getInches(field.caption.para.spaceBelow) + fy - (ty + th));
	}

	// make the field taller to include the distance between the top of the text to the top of the field.
	fh = fy - ty + fh;
	fy = ty;
	var space = {left: 0, right:0, top: 0, bottom: 0};
	// if the field has an outer-border, we want to move it to be a widget border
	// Otherwise the border will expand to include the new caption.
	if (field.isPropertySpecified("border") && field.border.presence === "visible") {
		if (field.isPropertySpecified("margin")) {
			space.top = getInches(field.margin.topInset);
			space.left = getInches(field.margin.leftInset);
			space.bottom = getInches(field.margin.bottomInset);
			space.right = getInches(field.margin.rightInset);
			field.nodes.remove(field.margin);
		}
		if (!field.ui.oneOfChild.isPropertySpecified("border") || field.ui.oneOfChild.border.presence === "hidden") {
			field.ui.oneOfChild.nodes.remove(field.ui.oneOfChild.border);
			// adding the border to the widget also removes it from the field.
			field.ui.oneOfChild.nodes.append(field.border);
			// reduce the caption reserve to make room for the width of the top and bottom borders
			// Normally we might fix this by adjusting the margins inside the widget.  problem is that the
			// Acrobat widget doesn't support arbitrary internal margins -- and there is no UI in Designer 
			// to re-adjust these margins after they've been set.
			// So we're best to simply use the default (acrobat widget) margins and adjust other box model parameters
			var nThick;
//			var nReserve = getInches(field.caption.reserve);
			var vTopEdge = field.ui.oneOfChild.border.getElement("edge", 0);
			if (vTopEdge.presence === "visible") {
//				nReserve = nReserve - getInches(vTopEdge.thickness);
				nThick = getInches(vTopEdge.thickness) - space.top;
				if (nThick > 0) {
					fy = fy - nThick;
					fh = fh + nThick;
				}
			}
			var vLeftEdge = field.ui.oneOfChild.border.getElement("edge", 3);
			if (vLeftEdge.presence === "visible") {
//				nReserve = nReserve - getInches(vTopEdge.thickness);
				nThick = getInches(vLeftEdge.thickness) - space.left;
				if (nThick > 0) {
					fx = fx - nThick;
					fw = fw + nThick;
				}
			}

			var vRightEdge = field.ui.oneOfChild.border.getElement("edge", 1);
			if (vRightEdge.presence === "visible") {
//				nReserve = nReserve - getInches(vTopEdge.thickness);
				nThick = getInches(vRightEdge.thickness) - space.right;
				if (nThick > 0) {
					fw = fw + nThick;
				}
			}


			var vBottomEdge = field.ui.oneOfChild.border.getElement("edge", 2);
			if (vBottomEdge.presence === "visible") {
				nThick = getInches(vBottomEdge.thickness) - space.bottom;
				if (nThick > 0) {
					fh = fh + nThick;
				}
			}
//			field.caption.reserve = formatInches(nReserve);
		}
	}
	// get rid of the remnant text field.
    text.parent.nodes.remove(text);
	
	// Assign all the computed positions and dimensions.
	if (bGrowableY) {
		field.minH = formatInches(fh);
	} else {
		field.h = formatInches(fh);
	}
	field.y = formatInches(ty);
	field.x = formatInches(fx);
	if (bGrowableY) {
		field.minW = formatInches(fw);
	} else {
		field.w = formatInches(fw);
	}
} else {
	designer.alert("Must select a field(with no caption) and a text object");
}