'
'----------------------------
'--- Creation information ---
'----------------------------
'
'Name: calcep.ave
'Version: 1.1
'Date: 02/16/97
'Author: Ferdi Hellweger
'        Center for Research in Water Resources
'        The University of Texas at Austin
'        ferdi@crwr.utexas.edu
'
'---------------------------
'--- Purpose/Description ---
'---------------------------
'
'This program computes the bulk dispersion coefficient.
'
'---------------------------------------------
'--- Check if units configuration happened ---
'---------------------------------------------
'
if (not _configu) then
    configure = msgbox.yesno("Units are not configured.  Configure it now?","BALANCE",true)
    if (configure) then
        av.run("balconu", nil)
    else
        exit
    end
end
'
'----------------
'--- Get view ---
'----------------
'
theview = av.getactivedoc
'
'------------------
'--- Get themes ---
'------------------
'
theactivethemes = theview.getactivethemes
if (theactivethemes.count = 0) then
    msgbox.error("No active themes found", "BALANCE")
    exit
end
if (theactivethemes.count = 1) then
    msgbox.error("Only one active theme found", "BALANCE")
    exit
end
if (theactivethemes.count > 2) then
    msgbox.error("Too many active themes found", "BALANCE")
    exit
end
if (theactivethemes.count = 2) then
    lfound = false
    pfound = false
    for each activetheme in theactivethemes
        theftab = activetheme.getftab
        theshapef = theftab.findfield("shape")
        theshape = theftab.returnvalue(theshapef,0)
        if (theshape.getclass.getclassname = "polyline") then
            theltheme = activetheme
            lfound = true
        end
        if (theshape.getclass.getclassname = "polygon") then
            theptheme = activetheme
            pfound = true
        end
    end
end
if (not lfound) then
    msgbox.error("One theme needs to be a line theme", "BALANCE")
    exit
end
if (not pfound) then
    msgbox.error("One theme needs to be a polygon theme", "BALANCE")
    exit
end
'
'------------------------------
'--- Get calculation option ---
'------------------------------
'
choices = list.make
choices = choices.add("Area Field, a")
choices = choices.add("Depth Field, h and length")
'
mychoice = msgbox.listasstring(choices, "Take area from", "BALANCE")
if (mychoice = nil) then
    exit
end
'
'---------------------
'--- Set up themes ---
'---------------------
'
'line theme
'
lftab = theltheme.getftab
if (lftab = nil) then
    msgbox.error("Can't open line theme","BALANCE")
    exit 
end
'
lshapef = lftab.findfield("shape")
if (lshapef = nil) then
    msgbox.error("Can't find 'shape' field in line theme","BALANCE")
    exit
end
'
lpf = lftab.findfield("lpoly#")
if (lpf = nil) then
   lpf = lftab.findfield("lpoly_")
end
if (lpf = nil) then
    msgbox.error("Can't find 'lpoly#' field in line theme","BALANCE")
    exit
end
'
rpf = lftab.findfield("rpoly#")
if (rpf = nil) then
   rpf = lftab.findfield("rpoly_")
end
if (rpf = nil) then
    msgbox.error("Can't find 'rpoly#' field in line theme","BALANCE")
    exit
end
'
ef = lftab.findfield("e")
if (ef = nil) then
    addfield = msgbox.yesno("Can't find 'e' field in line theme.  Add it?","BALANCE", true)
    if (addfield) then
        lftab.seteditable(true)
        ef = field.make("e", #FIELD_DECIMAL, 16, 4)
        lftab.addfields({ef})
        lftab.seteditable(false)
    else
        exit
    end
end
'
epf = lftab.findfield("ep")
if (epf = nil) then
    addfield = msgbox.yesno("Can't find 'ep' field in line theme.  Add it?","BALANCE", true)
    if (addfield) then
        lftab.seteditable(true)
        ef = field.make("ep", #FIELD_DECIMAL, 16, 4)
        lftab.addfields({epf})
        lftab.seteditable(false)
    else
        exit
    end
end
'
if (mychoice = "Area Field, a") then
af = lftab.findfield("a")
if (af = nil) then
    addfield = msgbox.yesno("Can't find 'a' field in line theme.  Add it?","BALANCE", true)
    if (addfield) then
        lftab.seteditable(true)
        epf = field.make("a", #FIELD_DECIMAL, 16, 4)
        lftab.addfields({af})
        lftab.seteditable(false)
    else
        exit
    end
end
end
if (mychoice = "Depth Field, h and length") then
hf = lftab.findfield("h")
if (hf = nil) then
    addfield = msgbox.yesno("Can't find 'h' field in line theme.  Add it?","BALANCE", true)
    if (addfield) then
        lftab.seteditable(true)
        hf = field.make("h", #FIELD_DECIMAL, 16, 4)
        lftab.addfields({hf})
        lftab.seteditable(false)
    else
        exit
    end
end
end
'
'polygon theme
'
pftab = theptheme.getftab
if (pftab = nil) then
    msgbox.error("Can't open polygon theme","BALANCE")
    exit
end
'
pshapef = pftab.findfield("shape")
if (pshapef = nil) then
    msgbox.error("Can't find 'shape' field in polygon theme","BALANCE")
    exit
end
'
polyf = nil
if (theptheme.getsrcname.asstring.right(4) = ".shp") then
    pname = theptheme.getsrcname.asstring.astokens(".").get(0)+"#"
    polyf = pftab.findfield(pname)
end
if (polyf = nil) then
    pname = theptheme.getsrcname.asstring.astokens(".").get(0)+"_"
    polyf = pftab.findfield(pname)
end
if (polyf = nil) then
    pname = theptheme.getsrcname.asstring+"#"
    polyf = pftab.findfield(pname)
end
if (polyf = nil) then
    pname = theptheme.getsrcname.asstring+"_"
    polyf = pftab.findfield(pname)
end
if (polyf = nil) then
    msgbox.error("Can't find polygon number field in polygon theme","BALANCE")
    exit
end
'
'-----------------
'--- Calculate ---
'-----------------
'
'--- Initial set up ---
'
'make line attribute table editable
'
lftab.seteditable(true)
'
'make index for polygon attribute table
'
polydict = dictionary.make(pftab.getnumrecords * 2)
for each prec in pftab
    poly = pftab.returnvalue(polyf, prec)
    polydict.add(poly, prec.asstring.asnumber)
end
'
'--- Loop ---
'
for each lrec in lftab
    '
    'get line attributes
    '
    lp = lftab.returnvalue(lpf, lrec)
    rp = lftab.returnvalue(rpf, lrec)
    lshape = lftab.returnvalue(lshapef, lrec)
    e = lftab.returnvalue(ef, lrec)
    if (mychoice = "Area Field, a") then
        a = lftab.returnvalue(af, lrec)
    end
    if (mychoice = "Depth Field, h and length") then
        h = lftab.returnvalue(hf, lrec)
        pointlist = lshape.aslist
        length = 0
        for each twopoints in pointlist
            frompoint = twopoints.get(0)
            topoint = twopoints.get(1)
            thislength = frompoint.distance(topoint)
            length = length + thislength
        end
        a = length * h
    end
    '
    'calculate mixing length
    '
    if ((lp > 1) and (rp > 1)) then
        lpshape = pftab.returnvalue(pshapef, polydict.get(lp))
        lpcentroid = lpshape.returncenter
        rpshape = pftab.returnvalue(pshapef, polydict.get(rp))
        rpcentroid = rpshape.returncenter
        dx = lpcentroid.distance(rpcentroid)
    end
    if ((rp = 1) or (lp = 1)) then
        pointlist = lshape.asmultipoint.aslist
        fulllength = 0
        i = 1
        while (i < pointlist.count)
            fx = pointlist.get(i - 1).getx
            fy = pointlist.get(i - 1).gety
            tx = pointlist.get(i).getx
            ty = pointlist.get(i).gety
            length = (((fx - tx)^2) + ((fy - ty)^2)^0.5)
            fulllength = fulllength + length
            i = i + 1
        end
        partlength = 0
        i = 1
        centerfound = false
        while (i < pointlist.count)
            fx = pointlist.get(i - 1).getx
            fy = pointlist.get(i - 1).gety
            tx = pointlist.get(i).getx
            ty = pointlist.get(i).gety
            length = (((fx - tx)^2) + ((fy - ty)^2)^0.5)
            partlength = partlength + length
            if ((partlength >= (fulllength * 0.5)) and (not centerfound)) then
                fraction = ((fulllength * 0.5) - partlength + length) / length
                cx = fx + ((tx - fx) * fraction)
                cy = fy + ((ty - fy) * fraction)
                centerpoint = point.make(cx,cy)
                centerfound = true
            end
            i = i + 1
        end
    end
    if (rp = 1) then

if (polydict.get(lp) = nil) then
msgbox.info(lp.asstring, "DEBUG")
exit
end
        lpshape = pftab.returnvalue(pshapef, polydict.get(lp))
        lpcentroid = lpshape.returncenter
        dx = lpcentroid.distance(centerpoint) * 2
    end
    if (lp = 1) then
        rpshape = pftab.returnvalue(pshapef, polydict.get(rp))
        rpcentroid = rpshape.returncenter
        dx = rpcentroid.distance(centerpoint) * 2
    end
    '
    'calculate ep
    '
    ep = (e * a) / dx

    '
    'write ep to line attribute table
    '
    lftab.setvalue(epf, lrec, ep)
    '
end
'
'make line attribute table non editable
'
lftab.seteditable(false)
'
'final message to user
'
message = "Bulk Dispersion Coefficients, ep calculated"
msgbox.info(message,"BALANCE")
'
'-----------
'--- End ---
'-----------
'