marmots/scripting.py

from engine import *
from basetoken import *
from tpers import *
from util import *
from contextlib import contextmanager
from vm import *

# sobj -- generic hungarian for any object that is usable in scripts
# stmt -- statement; a synt that can be used as a line in a SyntBlock
def RegStmt(clsStmt):
    SyntLine.rgclsStmt.append(clsStmt)
    return clsStmt

def RegRtype(clsRtype):
    Rtype.rgclsRtype.append(clsRtype)
    return clsRtype

class Rtype(TPrs):
    "Runtime type"
    rgclsRtype = []
    @classmethod
    def RtypeMax(cls):
        "Return an instance of this rtype which will match anything that any instance of this rtype matches."
        return cls()
    def RglitFromSt(self, st):
        "Return literal objects that match a (partially entered) string."
        return []
    def RgsyntFromSt(self, syntBlock, st):
        "Return syntax objects whose rtypes match this that match a (partially entered) string."
        for lit in self.RglitFromSt(st):
            yield SyntLit(lit, self)
            
        for synt in self.RgsyntVarRefFromSt(syntBlock, st):
            yield synt
            
    def RgsyntVarRefFromSt(self, syntBlock, st):
        "Return variable references that match a (partially entered) string."
        while syntBlock != None:
            if isinstance(syntBlock, SyntBlock):
                for synt in self.RgsyntFromSyntBlock(syntBlock, st):
                    yield synt
            syntBlock = syntBlock.syntParent
        
    # helper for RgsyntVarRefFromSt
    def RgsyntFromSyntBlock(self, syntBlock, st):
        # yield all vars in scope
        for syntVar in syntBlock.rgsynt:
            if SyntVar.FVarOfType(syntVar, self) and syntVar.name.St().lower().startswith(st.lower()):
                yield SyntVarRef(syntVar)

    def StForSobj(self, sobj):
        "Return a user-visible description of a sobj."
        return str(sobj)
    def FMember(self, sobj):
        "Returns true if sobj is a member of this type."
        return isinstance(sobj, self.pythontype)
    def FOverlap(self, rtype):
        "Returns true if there is some overlap between this type and rtype."
        return isinstance(rtype, self.__class__)

@RegRtype
class RtypeBool(Rtype):
    pythontype = bool
    def RglitFromSt(self, st):
        if "true".startswith(st.lower()):
            yield True
        if "false".startswith(st.lower()):
            yield False
@RegRtype
class RtypeNum(Rtype):
    pythontype = float
    def RglitFromSt(self, st):
        try:
            yield float(st)
        except:
            pass
@RegRtype
class RtypeString(Rtype):
    pythontype = str
    def RglitFromSt(self, st):
        if st.startswith('"') or st.startswith("'"):
            yield st[1:]

class RtypeAny(Rtype):
    def RgsyntFromSt(self, syntBlock, st):
        for clsRtype in self.rgclsRtype:
            rtype = clsRtype.RtypeMax()
            for synt in rtype.RgsyntFromSt(syntBlock, st):
                yield synt
    def FMember(self, sobj):
        return True
    def FOverlap(self, rtype):
        return True
        
class Typeable(TPrs):
    def InitTransient(self):
        self.steditTypein = Stedit()
    def PersistStedit(self):
        assert self.FPersist()
        try:
            del self.steditTypein
        except:
            pass
        self.steditTypein = Stedit()
    def GetStTypein(self):
        st = self.steditTypein.GetValue()
        return None if st == "" else st 
    def SetStTypein(self, stTypein):
        self.steditTypein.SetValue(stTypein or "")
    def HandleTypeinKey(self, key):
        return self.steditTypein.HandleKey(key)
        
class Synt(Typeable):
    "A piece of syntax"
    def InitPersistent(self):
        self.syntParent = None
        self.rgsynt = []
        self.Populate()

    @classmethod
    def SyntDefault(cls):
        return cls()

    @classmethod
    def RgsyntReplace(cls, syntChild, st, rtype):
        return []

    def ProjectTypeinForChild(self, pwParent, syntChild, st):
        def OnSelect(synt, psel):
            self.Replace(syntChild, synt)
            syntChild.SetStTypein(None)
        if syntChild.GetStTypein() != None:
            pwParent = PwDropdown(pwParent)
        PwTypein(pwParent, st, syntChild)
        if syntChild.GetStTypein() != None:
            for synt in self.RgsyntForChild(syntChild, syntChild.GetStTypein()):
                PwButton(pwParent, synt.StForTypein(), synt, OnSelect)

    def RgsyntForChild(self, syntChild, st):
        return []
        
    def Replace(self, syntOld, syntNew):
        assert syntNew.syntParent == None
        syntNew.syntParent = self
        self.rgsynt[self.Isynt(syntOld)] = syntNew

    def Append(self, syntNew):
        assert syntNew.syntParent == None
        syntNew.syntParent = self
        self.rgsynt.append(syntNew)
        
    def Isynt(self, syntChild):
        if isinstance(syntChild, int):
            return syntChild
        return self.rgsynt.index(syntChild)
        
    def Rtype(self):
        return None
    
    def RtypeTopForChild(self, syntChild):
        return None
        
    def Populate(self):
        "Populate rgsynt with useful default values."
        pass
        
    def Project(self, pcur):
        "Project the current synt into its corresponding pws."
        pass
    def Compile(self):
        "Return a list of instrs to be interpreted.  See vm.py for details on what an instr can be."
        return [self.Eval]

        
# desc - list of desces
# desce:
#  string: "foo" -- literal uneditable text
#  list: ["foo"] -- text to edit the current synt
#  tuple: (clsSynt, type) -- child description
#         clsSynt: class of child synt
#         type: number - same as another child expression with that number
#               None - no rtype specified / possible
#               tuple (number, rtypeTop) - number == same as another child expression with that number, rtypeTop = required type
class SyntDesc(Synt):
    @classmethod
    def StForTypein(cls):
        for desce in cls.Desc():
            if isinstance(desce, list) and len(desce) == 1:
                return desce[0]

    @staticmethod
    def DefProp(isynt):
        "Create an alias for rgsynt[isynt]."
        def getI(self):
            return self.rgsynt[isynt]
        def setI(self, syntNew):
            self.Replace(isynt, syntNew)
        return property(getI, setI)

    @classmethod
    def Desc(cls):
        return cls.desc
    def Populate(self):
        for desce in self.Desc():
            if isinstance(desce, tuple):
                synt = desce[0].SyntDefault()
                self.Append(synt)
#        for synt in self.rgsynt:
#            synt.Populate()
    
    def DesceChild(self, isyntChild):
        isyntDesce = 0;
        for desce in self.Desc():
            if isinstance(desce, tuple):
                if isyntDesce == isyntChild:
                    return desce
                isyntDesce += 1
        return None        
        
    def RtypeTopForChild(self, syntChild):
        isyntChild = self.Isynt(syntChild)
        desce = self.DesceChild(isyntChild)
        if desce != None and isinstance(desce[1], tuple):
            return desce[1][0]
        return None

    def RgsyntForChild(self, syntChild, st):
        isyntChild = self.Isynt(syntChild)
        desce = self.DesceChild(isyntChild)
        if desce != None:
            rtype = None
            if isinstance(desce[1], tuple):
                rtype = desce[1][1]
            return desce[0].RgsyntReplace(syntChild, st, rtype)
        return []
    def Project(self, pcur):
        "adds more horizontal pws to a horizontal pw"        
        isynt = 0
        for desce in self.Desc():
            if isinstance(desce, str):
                PwStatic(pcur.PwHoriz(self), desce)
            elif isinstance(desce, list):
                # selection for the synt itself
                self.syntParent.ProjectTypeinForChild(pcur.PwHoriz(self), self, desce[0])
            elif isinstance(desce, tuple):
                # embedded syntax
                self.rgsynt[isynt].Project(pcur)
                isynt += 1
        
class SyntName(Synt):
    def InitPersistent(self):
        Synt.InitPersistent(self)
        self.PersistStedit()
    def Project(self, pcur):
        PwTypein(pcur.PwHoriz(self), self.St(), self)
    def St(self):
        return self.GetStTypein()
        
class SyntExpr(Synt):
    rgclsSyntOp = []
    @classmethod
    def RgsyntReplace(cls, syntChild, st, rtype):
        for synt in RtypeAny().RgsyntFromSt(syntChild.syntParent, st):
            yield synt
        for clsSyntOp in cls.rgclsSyntOp:
            if clsSyntOp.StForTypein().lower().startswith(st.lower()):
                yield clsSyntOp.SyntDefault()

    def Project(self, pcur):
        self.syntParent.ProjectTypeinForChild(pcur.PwHoriz(self), self, "     ")
    def Eval(self, vm):
        Fail.Push(vm, "Empty expression", self)

class SyntLine(SyntDesc):
    rgclsStmt = []
    desc = [["     "]]
    @classmethod
    def RgsyntReplace(cls, syntChild, st, rtype):
        for clsStmt in cls.rgclsStmt:
            if clsStmt.StForTypein().lower().startswith(st.lower()):
                yield clsStmt()
    def Compile(self):
        return []

class SyntBlock(Synt):
    def Project(self, pcur):
        with pcur.Indent(2 if pcur.pwHoriz != None else 0):
            pcur.EndLine()
            if pcur.pwVert == None:
                pcur.pwVert = PwBlock(None, self, pcur.dxindent)
            def OnInsertNewLine(syntAfter, psel):
                self.InsertLineAfter(syntAfter, None)
                psel.Inc(pcur.pwVert)
            PwButtonHidden(pcur.pwVert, "[insert new line]", None, OnInsertNewLine, pcur.dxindent)
            for syntLine in self.rgsynt:
                pwKey = PwKeyHandler(pcur.pwVert, self.HandleKey)
                with pcur.ProjectHoriz(pwKey, syntLine):
                    syntLine.Project(pcur)

    def RgsyntForChild(self, syntChild, st):
        return SyntLine.RgsyntReplace(syntChild, st, None)
        
    def InsertLineAfter(self, syntAfter, syntStmt):
        if syntStmt == None:
            syntStmt = SyntLine()
        if syntAfter == None:
            self.rgsynt.insert(0, syntStmt)
        else:
            self.rgsynt.insert(self.rgsynt.index(syntAfter) + 1, syntStmt)
        syntStmt.syntParent = self
        return syntStmt
        
    def HandleKey(self, pwKey, pov, psel, key):
        if ansi.FEnter(key):
            self.InsertLineAfter(pwKey.pwChild.Value(), None)
            psel.Inc(pwKey.PwParent())
            return True
        return False
    def Compile(self):
        return self.rgsynt
    
class SyntLit(Synt):
    def InitPersistent(self, value, rtype):
        Synt.InitPersistent(self)
        self.value = value
        self.rtype = rtype
    def StForTypein(self):
        return self.rtype.StForSobj(self.value)
    def Rtype(self):
        return self.rtype
    def Project(self, pcur):
        self.syntParent.ProjectTypeinForChild(pcur.PwHoriz(self), self, self.StForTypein())
    def Eval(self, vm):
        vm.Push(self.value)

@RegStmt
class SyntVar(SyntDesc):
    desc = [["Define"], " ", (SyntName, None), " to be ", (SyntExpr, 1)]
    name = SyntDesc.DefProp(0)
    expr = SyntDesc.DefProp(1)
    @classmethod
    def FVarOfType(cls, synt, rtype):
        return isinstance(synt, cls) and synt.expr != None and rtype.FOverlap(synt.expr.Rtype())
    def Compile(self):
        return [self.expr, self.Eval]
    def Eval(self, vm):
        vm.vars.Define(self, vm.Pop())
        
class SyntVarRef(Synt):
    def InitPersistent(self, syntVar = None):
        Synt.InitPersistent(self)
        self.syntVar = syntVar
    @classmethod
    def RgsyntReplace(cls, syntChild, st, rtype):
        rtype = rtype or RtypeAny()
        return rtype.RgsyntVarRefFromSt(syntChild, st)
    def Rtype(self):
        return self.syntVar.Rtype()
    def StForTypein(self):
        if self.syntVar:
            return self.syntVar.name.St()
        return "<var>"
    def Project(self, pcur):
        self.syntParent.ProjectTypeinForChild(pcur.PwHoriz(self), self, self.StForTypein())
    def Eval(self, vm):
        vm.Push(vm.vars.Get(self.syntVar, self))
        
class SyntBinOp(SyntDesc):
    @classmethod
    def Desc(cls):
        return [(SyntExpr, None), " ", [cls.op], " ", (SyntExpr, None)]
    left = SyntDesc.DefProp(0)
    right = SyntDesc.DefProp(1)
    @classmethod
    def Create(cls, op, rtype, dgEval = None, stNameI = None):
        def Decorate(dgEval):
            stName = stNameI or dgEval.__name__
            def Eval(self, vm):
                right = vm.Pop()
                left = vm.Pop()
                try:
                    vm.Push(dgEval(left, right))
                except Exception as e:
                    Fail.Push(vm, "Failed to " + op + ": " + str(e), self)
            def Compile(self):
                return [self.left, self.right, self.Eval]
            clsNew = type(stName, (cls,), {"Compile": Compile, "Eval": Eval, "op": op})
            SyntExpr.rgclsSyntOp.append(clsNew)
            return clsNew

        if dgEval == None: # used as a decorator
            return Decorate
        clsNew = Decorate(dgEval)
        if stNameI != None:
            globals()[stNameI] = clsNew
        return clsNew

SyntBinOp.Create("+", RtypeNum(), lambda l,r: l + r, "SyntPlus")
SyntBinOp.Create("-", RtypeNum(), lambda l,r: l - r, "SyntMinus")
SyntBinOp.Create("*", RtypeNum(), lambda l,r: l * r, "SyntMult")
SyntBinOp.Create("/", RtypeNum(), lambda l,r: l / r, "SyntDiv") # use ansi?
SyntBinOp.Create("=", RtypeBool(), lambda l,r: l == r, "SyntEq")
SyntBinOp.Create(">", RtypeBool(), lambda l,r: l > r, "SyntGt")
SyntBinOp.Create(">=", RtypeBool(), lambda l,r: l >= r, "SyntGte") # use ansi?
SyntBinOp.Create("<", RtypeBool(), lambda l,r: l < r, "SyntLt")
SyntBinOp.Create("<=", RtypeBool(), lambda l,r: l <= r, "SyntLte") # use ansi?
SyntBinOp.Create("and", RtypeBool(), lambda l,r: l and r, "SyntAnd")
SyntBinOp.Create("or", RtypeBool(), lambda l,r: l or r, "SyntOr")

@RegStmt    
class SyntIf(SyntDesc):
    desc = [["If"], " ", (SyntExpr, (1, RtypeBool)), ", then:", (SyntBlock, None), "or else:", (SyntBlock, None)]
    expr = SyntDesc.DefProp(0)
    blockIfTrue = SyntDesc.DefProp(1)
    blockIfFalse = SyntDesc.DefProp(2)
    def Compile(self):
        return [self.expr, self.Compare, self.PopCtx]
    def Compare(self, vm):
        val = vm.Pop()
        vm.vars.Push() # lexical scoping, bitches
        if val:
            return self.blockIfTrue
        else:
            return self.blockIfFalse
    def PopCtx(self, vm):
        vm.vars.Pop()

@RegStmt
class SyntSet(SyntDesc):
    desc = [["Set"], " ", (SyntVarRef, 1), " to ", (SyntExpr, 1)]
    lvalue = SyntDesc.DefProp(0)
    expr = SyntDesc.DefProp(1)
    def Compile(self):
        return [self.expr, self.Eval]
    def Eval(self, vm):
        val = vm.Pop()
        if not isinstance(val, Fail):
            vm.Log(vm.vars.Set(self.lvalue.syntVar, vm.Pop(), self))

#debug
@RegStmt
class SyntPrint(SyntDesc):
    desc = [["Print"], " ", (SyntExpr, 1)]
    expr = SyntDesc.DefProp(0)
    def Compile(self):
        return [self.expr, self.Eval]
    def Eval(self, vm):
        print vm.Pop()

class Fail(TPrs):
    """
    Failure object.  Our scripting language has no exceptions; instead, if a failure object is involved in a calculation, 
    that calculation fails as well.  Inspired by Icon.  I would like this model to have the property that the designer can
    edit a script while the game is running and see the effect of their changes immediately; this suggests that failures
    should be logged and the script should continue to run.
    """
    def InitPersistent(self, stFailure, synt):
        self.stFailure = stFailure
        self.synt = synt
    @staticmethod
    def Push(vm, stFailure, synt):
        fail = Fail(stFailure, synt)
        vm.Push(fail)
        vm.Log(fail)
    @staticmethod
    def Log(vm, stFailure, synt):
        vm.Log(Fail(stFailure, synt))

# projection cursor
class Pcur(object):
    @staticmethod
    def PwProjected(synt):
        pcur = Pcur()
        synt.Project(pcur)
        return pcur.pwVert
        
    def __init__(self):
        self.pwVert = None
        self.pwHoriz = None
        self.dxindent = 0

    @contextmanager
    def Indent(self, dxindent = 2):
        self.dxindent += dxindent
        yield
        self.dxindent -= dxindent

    @contextmanager
    def ProjectHoriz(self, pwParent, synt):
        self.ProjectHorizI(pwParent, synt)
        yield
        self.EndLine()
        
    def PwHoriz(self, synt):
        if self.pwHoriz == None:
            self.ProjectHorizI(self.pwVert, synt)
        return self.pwHoriz
    
    def EndLine(self):
        self.pwHoriz = None
        
    def ProjectHorizI(self, pwParent, synt):
        self.pwHoriz = PwList(pwParent, synt, self.dxindent)

# pw - projected widget
# Nothing ever depends on the object identity or permanence of a pw!
# They are generated on demand, whenever we need to draw or process a
# keypress.

class Pw(object):
    def __init__(self, pwParent):
        if pwParent != None:
            pwParent.AddChild(self)
        self.pwParent = pwParent
    def PrintTree(self, dxindent = 0):
        print (" " * dxindent) + self.StDebug()
        for pwChild in self.RgpwChild():
            pwChild.PrintTree(dxindent + 2)
    def StDebug(self):
        return self.__class__.__name__
    def PwParent(self):
        return self.pwParent
    def Value(self):
        return None
    def FSelectable(self):
        return False
    def FContainer(self):
        return False
    def RgpwChild(self):
        return []
    def HandleKey(self, pov, psel, key):
        return False
    def PwFirstSelectable(self):
        if self.FSelectable():
            return self
        for pwChild in self.RgpwChild():
            pw = pwChild.PwFirstSelectable()
            if pw != None:
                return pw
        return None
    
class PwContainer(Pw):
    def __init__(self, pwParent):
        Pw.__init__(self, pwParent)
        self.rgpwContents = []
    def AddChild(self, pw):
        self.rgpwContents.append(pw)
    def RgpwChild(self):
        return self.rgpwContents
    def FContainer(self):
        return True

class PwContainOne(Pw):
    def AddChild(self, pw):
        self.pwChild = pw
    def RgpwChild(self):
        return [self.pwChild]
    def FContainer(self):
        return True
    
class PwExpand(PwContainOne):
    def DxDyNew(self, w, dxStart, mpksel):
        dxdy = self.pwChild.DxDyNew(w, dxStart, mpksel)
        if dxdy[0] == 0 and dxdy[1] > 0:
            return dxdy
        return (0, dxdy[0] + 1)
    def Draw(self, ascr, x, y, w, dxStart, mpksel, fOverlay):
        if not fOverlay:
            ascr.PutSt(" " * w, x, y, self.pwChild.ColFg(), self.pwChild.ColBg(mpksel.Get(self.pwChild)))
            self.pwChild.Draw(ascr, x, y, w, dxStart, mpksel, fOverlay)
            
class PwStatic(Pw):
    def __init__(self, pwParent, stText):
        Pw.__init__(self, pwParent)
        self.stText = stText
    def StDebug(self):
        return Pw.StDebug(self) + " '" + self.StTextDisplay(Ksel.NAV) + "'"
    def DxDyNew(self, w, dxStart, mpksel):
        rgsnippet = self.Rgsnippet(w, dxStart, mpksel)
        if len(rgsnippet) == 1:
            return (dxStart + len(rgsnippet[0].st), 0)
        else:
            return (len(rgsnippet[-1].st), len(rgsnippet) - 1)
    def StTextDisplay(self, ksel):
        return self.stText
    def Rgsnippet(self, w, dxStart, mpksel):
        ksel = mpksel.Get(self)
        return list(RgSnippetWrapped(self.StTextDisplay(ksel), w, ksel == Ksel.NAV, dxStart))
    def ColBg(self, ksel):
        return ansi.BLACK
    def ColFg(self):
        return ansi.WHITE | ansi.FBRIGHT
    def RgSnippetXY(self, x, y, w, dxStart, mpksel):
        fFirst = True
        for snippet in self.Rgsnippet(w, dxStart, mpksel):
            xT = x + dxStart if fFirst else x
            yield (snippet, xT, y)
            y = y + 1
            fFirst = False
    def Draw(self, ascr, x, y, w, dxStart, mpksel, fOverlay):
        if not fOverlay:
            ksel = mpksel.Get(self)
            for (snippet, x, y) in self.RgSnippetXY(x, y, w, dxStart, mpksel):
                ascr.PutSt(snippet.st, x, y, self.ColFg(), self.ColBg(ksel))

class PwTypein(PwStatic):
    def __init__(self, pwParent, stSobj, typeable):
        if typeable.GetStTypein() == None:
            stDisplay = stSobj
        else:
            stDisplay = None
        PwStatic.__init__(self, pwParent, stDisplay)
        self.typeable = typeable
    def Value(self):
        return self.typeable
    def StTextDisplay(self, ksel):
        if self.stText == None:
            return self.typeable.steditTypein.StForSize(ksel == Ksel.NAV)
        return self.stText
    def FSelectable(self):
        return True
    def ColBg(self, ksel):
        if ksel == Ksel.NAV:
            return ansi.YELLOW
        elif ksel == Ksel.OTHERNAV:
            return ansi.MAGENTA
        return ansi.BLUE
    def HandleKey(self, pov, psel, key):
        return self.typeable.HandleTypeinKey(key)
    def Draw(self, ascr, x, y, w, dxStart, mpksel, fOverlay):
        if not fOverlay:
            ksel = mpksel.Get(self)
            fTextSelect = ksel == Ksel.NAV and self.typeable.GetStTypein() != None
            for (snippet, x, y) in self.RgSnippetXY(x, y, w, dxStart, mpksel):
                ascr.PutSt(snippet.st, x, y, self.ColFg(), self.ColBg(Ksel.NONE if fTextSelect else ksel))
                if fTextSelect:
                    self.typeable.steditTypein.DrawCursor(ascr, x, y, self.ColFg(), self.ColBg(ksel), snippet)
        else:
            for pwChild in self.RgpwChild():
                pwChild.Draw(ascr, x, y, dxStart, mpksel, fOverlay)

class PwButton(PwStatic):
    def __init__(self, pwParent, stText, value, dgEnter):
        PwStatic.__init__(self, pwParent, stText)
        self.value = value
        self.dgEnter = dgEnter
    def Value(self):
        return self.value
    def FSelectable(self):
        return True
    def ColBg(self, ksel):
        if ksel == Ksel.NAV:
            return ansi.YELLOW
        elif ksel == Ksel.OTHERNAV:
            return ansi.MAGENTA
        return ansi.BLUE
    def ColFg(self):
        return ansi.BLUE | ansi.FBRIGHT
    def HandleKey(self, pov, psel, key):
        if key == ansi.K_RETURN:
            self.dgEnter(self.Value(), psel)
            return True
        return False

class PwButtonHidden(PwButton):
    def __init__(self, pwParent, stText, value, dgEnter, dxIndent):
        PwButton.__init__(self, pwParent, stText, value, dgEnter)
        self.dxIndent = dxIndent
    def DxDyNew(self, w, dxStart, mpksel):
        if mpksel.Get(self) == Ksel.NAV:
            return PwButton.DxDyNew(self, w - self.dxIndent, dxStart + self.dxIndent, mpksel)
        return (0, 0)
    def Draw(self, ascr, x, y, w, dxStart, mpksel, fOverlay):
        if mpksel.Get(self) == Ksel.NAV:
            PwButton.Draw(self, ascr, x + self.dxIndent, y, w - self.dxIndent, dxStart, mpksel, fOverlay)

class PwKeyHandler(PwContainOne):
    def __init__(self, pwParent, dgHandleKey):
        PwContainOne.__init__(self, pwParent)
        self.dgHandleKey = dgHandleKey
    def DxDyNew(self, w, dxStart, mpksel):
        return self.pwChild.DxDyNew(w, dxStart, mpksel)
    def Draw(self, ascr, x, y, w, dxStart, mpksel, fOverlay):
        self.pwChild.Draw(ascr, x, y, w, dxStart, mpksel, fOverlay)
    def HandleKey(self, pov, psel, key):
        self.dgHandleKey(self, pov, psel, key)
        
class PwBlock(PwContainer):
    def __init__(self, pwParent, block, dxIndent = 2):
        PwContainer.__init__(self, pwParent)
        self.block = block
        self.dxIndent = dxIndent
    def Value(self):
        return self.block
    def DxIndent(self):
        return self.dxIndent
    def DxDyNew(self, w, dxStart, mpksel):
        return (0, 1 + sum([pw.DxDyNew(w - self.DxIndent(), 0, mpksel)[1] + 1 for pw in self.rgpwContents]))
    def RgpwChildToDraw(self):
        return self.RgpwChild()
    def Draw(self, ascr, x, y, w, dxStart, mpksel, fOverlay):
        for pw in self.RgpwChildToDraw():
            pw.Draw(ascr, x + self.DxIndent(), y, w - self.DxIndent(), 0, mpksel, fOverlay)
            (dxNew, dyNew) = pw.DxDyNew(w - self.DxIndent(), 0, mpksel)
            if dxNew > 0 or dyNew > 0:
                y = y + dyNew + 1
    def HandleKey(self, pov, psel, key):
        if key == ansi.K_UP:
            return psel.Dec(self)
        elif key == ansi.K_DOWN:
            return psel.Inc(self)
        elif key == ansi.K_DEL:
            pass
        return False

class PwDropdown(PwBlock):
    def __init__(self, pwParent):
        PwBlock.__init__(self, pwParent, None, 0)
    def WidthMax(self, mpksel):
        w = -1
        for pw in self.RgpwChild():
            wPw = pw.DxDyNew(1000000, 0, mpksel)[0]
            if wPw > w:
                w = wPw
        return w
    def RgpwChildToDraw(self):
        return PwBlock.RgpwChild(self)[1:]
    def PwChildFirst(self):
        return PwBlock.RgpwChild(self)[0]
    def DxDyNew(self, w, dxStart, mpksel):
        return self.PwChildFirst().DxDyNew(w, dxStart, mpksel)
    def Draw(self, ascr, x, y, w, dxStart, mpksel, fOverlay):
        if not fOverlay:
            self.PwChildFirst().Draw(ascr, x, y, w, dxStart, mpksel, False)
        else:
            wMax = self.WidthMax(mpksel)
            w = w - dxStart
            x = x + dxStart
            if x + wMax > w and wMax < w:
                x = w - self.WidthMax(mpksel)
            PwBlock.Draw(self, ascr, x, y + 1, w, 0, mpksel, False)

class PwList(PwContainer):
    def __init__(self, pwParent, synt, dxIndent):
        PwContainer.__init__(self, pwParent)
        self.synt = synt
        self.dxIndent = dxIndent
    def Value(self):
        return self.synt
    def DxDyNew(self, w, dxStart, mpksel):
        dx = dxStart
        dy = 0
        for pw in self.rgpwContents:
            (dx, dyPw) = pw.DxDyNew(w, dx, mpksel)
            dy = dy + dyPw
        return (dx, dy)
    def DxIndent(self):
        return self.dxIndent
    def Draw(self, ascr, x, y, w, dx, mpksel, fOverlay):
        for pw in self.rgpwContents:
            pw.Draw(ascr, x + self.DxIndent(), y, w - self.DxIndent(), dx, mpksel, fOverlay)
            (dx, dy) = pw.DxDyNew(w, dx, mpksel)
            y = y + dy 
    def HandleKey(self, pov, psel, key):
        if key == ansi.K_LEFT:
            return psel.Dec(self)
        elif key == ansi.K_RIGHT:
            return psel.Inc(self)
        return False

class Ksel(object):
    FOTHER = 0x2000
    NONE = FOTHER | 0x1000 # OR together all ksel flags and add 0x1000; largest possible ksel
    NAV = 0
    OTHERNAV = NAV | FOTHER 

    @staticmethod
    def KselBest(ksel1, ksel2):
        if ksel1 < ksel2:
            return ksel1
        return ksel2

class Psel(TPrs):
    def InitPersistent(self, pw, ksel):
        assert len(pw.RgpwChild()) == 0 #leaf
        self.rgo_ipw = self.Rgo_ipwFromPw(pw)
        self.ksel = ksel

    def Rgo_ipwFromPw(self, pw):
        rgo_ipw = []
        if pw != None:
            while pw.PwParent() != None:
                rgo_ipw.insert(0, (pw.Value(), pw.PwParent().RgpwChild().index(pw)))
                pw = pw.PwParent()
        return rgo_ipw
    
    def Validate(self, pwRoot):
        assert pwRoot.PwParent() == None #root
        io_ipw = 0
        pwSelected = pwRoot
        while len(pwSelected.RgpwChild()) > 0 and io_ipw < len(self.rgo_ipw):
            (o, ipw) = self.rgo_ipw[io_ipw]
            ipwNew = 0
            for pwChild in pwSelected.RgpwChild():
                if o != None and pwChild.Value() == o:
                    break
                ipwNew = ipwNew + 1
            if ipwNew == len(pwSelected.RgpwChild()):
                ipwLim = ipw + 1 if ipw < len(pwSelected.RgpwChild()) else len(pwSelected.RgpwChild())
                ipwNew = IoDec(pwSelected.RgpwChild(), ipwLim, self.FPwValid)
            if ipwNew < 0:
                break
            pwSelected = pwSelected.RgpwChild()[ipwNew]
            io_ipw = io_ipw + 1
                
        # we've made our best guess as to what the closest selectable thing is -- now make sure we point at SOMEthing selectable.
        if not pwSelected.FSelectable():
            pwT = pwSelected
            while pwT != None:
                pwSelected = pwT.PwFirstSelectable()
                if pwSelected != None:
                    break
                pwT = pwT.PwParent()
        
        self.rgo_ipw = self.Rgo_ipwFromPw(pwSelected)

    def FPwValid(self, pw):
        if pw.FSelectable():
            return True
        for pwChild in pw.RgpwChild():
            if self.FPwValid(pwChild):
                return True
        return False
        
    def Value(self, pwRoot):
        self.Validate(pwRoot)
        if len(self.rgo_ipw) > 0:
            return self.rgo_ipw[-1][0]
        return None
    
    def PwSelected(self, pwRoot, clevel = None):
        self.Validate(pwRoot)
        return self.PwSelectedI(pwRoot, self.rgo_ipw[:clevel])

    def PwSelectedI(self, pw, rgo_ipw):
        for (_, ipw) in rgo_ipw:
            pw = pw.RgpwChild()[ipw]
        return pw
    # contract: pwContainer is actually selected
    def Inc(self, pwContainer):
        return self.ChangeI(pwContainer, IoInc)
    def Dec(self, pwContainer):
        return self.ChangeI(pwContainer, IoDec)
        
    def ChangeI(self, pwContainer, fnChange):
        clevelChild = 1
        pwRoot = pwContainer
        while pwRoot.PwParent() != None:
            clevelChild = clevelChild + 1
            pwRoot = pwRoot.PwParent()
        self.Validate(pwRoot)
        assert self.PwSelected(pwRoot, clevelChild).PwParent() == pwContainer

        ipw = self.rgo_ipw[clevelChild - 1][1]
        rgpw = pwContainer.RgpwChild()
        ipwNew = fnChange(rgpw, ipw, self.FPwValid)
        self.rgo_ipw[clevelChild - 1] = (rgpw[ipwNew].Value(), ipwNew)
        self.Validate(pwRoot)
        return ipwNew != ipw

# projector overlay -- handles navigation, drawing the projection, etc
class Pov(TokenClient):
    def InitPersistent(self, owner, client, block):
        TokenClient.InitPersistent(self, owner, client, "drawable", "overlay")
        self.block = block
        self.pselstate = self.game.rgtoken("pselstate")[0] 
        
    def PwProjected(self):
        return Pcur.PwProjected(self.block)
    
    def run(self):
        while True:
            key = self.client.evKey.receive(self)
            if key == ansi.K_PGDN:
                Vm().RunSynt(self.block)
                continue
            psel = self.pselstate.PselByClient(self.client)
            pwSel = psel.PwSelected(self.PwProjected())
            while pwSel != None:
                if pwSel.HandleKey(self, psel, key):
                    break
                pwSel = pwSel.PwParent()
    
    def draw(self, ascr, client):
        if client == self.client:
            pw = self.PwProjected()
            mpksel = self.pselstate.GetMpksel(pw, client)
            pw.Draw(ascr, 1, 1, ascr.W(), 0, mpksel, False)
            pw.Draw(ascr, 1, 1, ascr.W(), 0, mpksel, True)

class PselState(Token):
    def InitPersistent(self, owner, block):
        Token.InitPersistent(self, owner, "pselstate")
        self.block = block
    def InitTransient(self):
        Token.InitTransient(self)
        self.mpclient_psel = {}
    def OnLeave(self, client):
        del self.mpclient_psel[client]
    def OnJoin(self, client):
        print "client joined,", client
        self.mpclient_psel[client] = Psel(Pcur.PwProjected(self.block).PwFirstSelectable(), Ksel.NAV)
    class Mpksel(object):
        def __init__(self, pwRoot, client, mpclient_psel):
            self.mppw_ksel = {}
            for clientT, psel in mpclient_psel.items():
                kselNew = Ksel.NAV
                if clientT != client:
                    kselNew = kselNew | Ksel.FOTHER
                pw = psel.PwSelected(pwRoot)
                self.mppw_ksel[pw] = Ksel.KselBest(kselNew, self.Get(pw))

        def Get(self, pw):
            return self.mppw_ksel.get(pw, Ksel.NONE)
        
    def GetMpksel(self, pwRoot, client):
        return self.Mpksel(pwRoot, client, self.mpclient_psel)
    def PselByClient(self, client):
        return self.mpclient_psel[client]
    def run(self):
        print "pselstate running"
        with self.game.evLeave.oob(self, self.OnLeave):
            while True:
                self.OnJoin(self.game.evJoin.receive(self))
                
class GameScriptTest(Game):
    def InitPersistent(self):
        Game.InitPersistent(self)
        self.block = SyntBlock()
        
    def GetRgclsTokTrans(self):
        return [[PselState, self.block], [AutoJoiner, [Pov, self.block]]]

class RunnerScriptTest(Runner):
    def InitPersistent(self):
        self.game = GameScriptTest()
        Runner.InitPersistent(self)

    def RunGame(self, client):
        client.joinGame(self.game)

if __name__ == "__main__":
    Run(RunnerScriptTest, "script_test.marm")