' ************************************************************
' Cut holes.ave

' This script is used for to fix shapefiles that have the holes
' listed as separate polygons, rather than cut out.

' It was written by Timothy S. Thomas.
' Editing began on 3/16/04, and was last edited on 3/16/04.
' It is based on "explode to new file" and "find neighbors".
' ************************************************************


theView = av.GetActiveDoc
theFTheme = theView.GetActiveThemes.Get(0)
theFTab = theFTheme.GetFTab
numRecs = theFTab.GetNumRecords
shapeField = theFTab.FindField("Shape")


' **********************************************************
' Create a new shapefile to hold the new shapes 
' **********************************************************

' Shows message in message bar
av.ShowMsg("Creating exploded file")

' Creates file
FTabFN = theFTab.GetSrcName.GetFileName
baseString = FTabFN.GetBaseName
extString = FTabFN.GetExtension
newString = FTabFN.AsString.Substitute(baseString,"")
new2String = baseString.Substitute(extString,"shp")
newFTabFN = FileDialog.Put(
          (newString + "cleaned " + new2String).AsFileName,
          "*.shp","Shapefile name")
newFTab = FTab.MakeNew(newFTabFN,Polygon) 
                                                 

' **********************************************************
' This allows the user to pick a field as the basic unit for
' evaluation
' **********************************************************

' Gets new field list, reflecting deletions of fields
fieldList = theFTab.GetFields.Clone
idField = MsgBox.ChoiceAsString(fieldList,"Select unit ID field",
            "Choose ID field")


' **********************************************************
' Establish unique polygon id
' **********************************************************

fieldList.Insert("<Make new unique id field>")
uniqidString = MsgBox.ChoiceAsString(fieldList,"Select Unique ID field",
            "Choose Unique ID field")
if (uniqidString = "<Make new unique id field>") then
	theFTab.SetEditable(True)
	isFld = theFTab.FindField("UniqID")
	if (isFld <> nil) then
		idnew = MsgBox.YesNo("UniqID is already a field.  Do you want to use it?",
                         "Use UniqID?",True)
		if (idnew) then
			uniqidField = isFld
		else
			newName = MsgBox.Input("Name of new ID","New name","NewID")
			uniqidField = Field.Make(newName,#FIELD_LONG,8,0)
			theFTab.AddFields({uniqidField})
			for each rec in theFTab
				theFTab.SetValue(uniqidField,rec,rec+1)
			end
		end
	else
		uniqidField = Field.Make("UniqID",#FIELD_LONG,8,0)
		theFTab.AddFields({uniqidField})
		for each rec in theFTab
			theFTab.SetValue(uniqidField,rec,rec+1)
		end
	end
	theFTab.SetEditable(False)
else
	uniqidField = uniqidString
end
uniqidString = uniqidField.AsString


' **********************************************************
' Clone fields for newFTab
' **********************************************************
newshapeField = newFTab.FindField("Shape")
inFields = theFTab.GetFields
newFields = List.Make
for each f in inFields
	if (f.GetName <> "shape") then
		newFields.Add(f.Clone)
	end
end
newFTab.AddFields(newFields)


' **********************************************************
' Selecting records one at a time and adding to newFTab
' **********************************************************

av.ShowStopButton
av.ShowMsg("Cleaning polygons and cutting holes")
for each recnum in 0..(numrecs-1) 
	theShape = theFTab.ReturnValue(shapeField,recnum)
	theID = theFTab.ReturnValue(idField,recnum)
	theuniqID = theFTab.ReturnValue(uniqidField,recnum)
	theArea = theShape.ReturnArea
	theFTab.SelectByPolygon(theShape,#VTAB_SELTYPE_NEW)
	outCode = 1
	outShape = theShape

	' **********************************************************
	' Checks to see if polygon is contained.  If so, it is 
	' skipped.  If it contains other polys, then subtracts
	' them.  If neither, then simply output.
	' **********************************************************

	for each s in theFTab.GetSelection
		otherPoly = theFTab.ReturnValue(shapeField,s)
		otherID = theFTab.ReturnValue(idField,s)
		otheruniqID = theFTab.ReturnValue(uniqidField,s)
		otherArea = otherPoly.ReturnArea
		edgeCode = 0
		if ((otheruniqID <> theuniqID) And (otherID = theID)) then
			area = theShape.ReturnIntersection(otherPoly).ReturnArea
			if (area.IsNull) then
				area = otherPoly.ReturnIntersection(theShape).ReturnArea
			end
			if (area.IsNull.Not) then
				if (theShape.Contains(otherPoly)) then
					outShape = outShape.ReturnDifference(otherPoly)
					edgeCode = 1
					if (outCode = 1) then
						outCode = 2
					elseif (outCode = 0) then
						outCode = 3
						MsgBox.Info("This shape has and island within a lake within an island at" ++ theID.AsString,"IMPORTANT")
					end
				end
				if (otherPoly.Contains(theShape)) then
					edgeCode = 1
					if (outCode = 1) then
						outCode = 0
					elseif (outCode = 2) then
						outCode = 3
						MsgBox.Info("This unit has and island within a lake within an island at" ++ theID.AsString,"IMPORTANT")
					end
				end
				if (edgeCode = 0) then
					if ((area > (0.95*theArea)) Or (area > (0.95*otherArea))) then
						MsgBox.Info("This unit has a probable boundary hole which ArcView could not find" ++ theID.AsString,"IMPORTANT")
					end
				end
			end
		end
		
	end

	if ((outCode = 1) Or (outCode = 2)) then
		rec = newFTab.AddRecord
		newFTab.SetValue(newshapeField,rec,outShape)
		for each fld in theFTab.GetFields
			fldName = fld.GetName
			if (fldName <> "shape") then
				newfld = newFTab.FindField(fldName)
				val = theFTab.ReturnValue(fld,recnum)
				newFTab.SetValue(newfld,rec,val)
			end
		end
	end

	av.SetStatus(100*(recnum+1)/numrecs)
	av.ShowMsg("Cleaning polygons and cutting holes"++recnum.AsString++"out of"++numrecs.AsString)
	
end

' Clears message in message bar
av.ClearMsg

' Turns off editing in the FTab
newFTab.SetEditable(false)
newFTheme = FTheme.Make ( newFTab )
theView.AddTheme ( newFTheme )
theFTheme.ClearSelection

' Removes garbage objects
av.PurgeObjects