"""
Easier access to matlab functions and variables.
Requires PyMat, http://claymore.engineer.gvsu.edu/~steriana/Python
Copyright Nathan Srebro, MIT, 2001
nati@mit.edu http://www.ai.mit.edu/~nati/Python
"""

try: import pymat
except: 
   class pymat:
      def __getattr__(self,attr): raise MatlabUnavialable
import types
import Numeric
import threading

class MatLabError(RuntimeError): pass
class MatlabUnavialable(MatLabError): pass

class matlab:
    def __init__(self,startcmd='',defer=0):
	self._startcmd = startcmd
        self._lock = threading.RLock()
	if not defer: self._handle = pymat.open(startcmd)
    def changestartcmd(self,startcmd=None):
	if startcmd is None: pass	# use empty string to set to nothing
	if hasattr(self,'_handle'):
	    if self._startcmd!=startcmd:
		raise RuntimeWarning,"MATLAB already initialized with startcmd=%s"%self._startcmd
	else: self._startcmd = startcmd
	
    def _makeactive(self):
        self._lock.acquire()
        try:
            if not hasattr(self,'_handle'): self._handle = pymat.open(self._startcmd)
        finally: self._lock.release()

    def __del__(self):
        try: pymat.close(self._handle)
        except AttributeError: pass

    def __call__(self, string, check=1):
        self._lock.acquire()
        try:
            self._makeactive()
            if check: dostring = "pymatlabok=0 ; "+string+" ; pymatlabok=1"
            else: dostring = string
            pymat.eval(self._handle,dostring)
            if check and not self['pymatlabok'][0]:
                raise MatLabError,"Operation %s failed"%string
        finally: self._lock.release()

    def __getitem__(self, name):
        self._lock.acquire()
        try:
            self._makeactive()
            return pymat.get(self._handle, name)
        finally: self._lock.release()

    def __setitem__(self, name, data):
        self._lock.acquire()
        try:
            self._makeactive()
            if not isinstance(data,types.StringType):
                data = Numeric.asarray(data)
                datashape = Numeric.shape(data)
                if not datashape: data=Numeric.reshape(data,(1,))
                elif len(datashape)>2: data=Numeric.ravel(data)
            pymat.put(self._handle, name, data)
            if len(datashape)>2:
                self('%s = reshape(%s,[%s])'%(name," ".join(map(str,datashape)),name))
        finally: self._lock.release()

    def function(self,*arg,**kwargs):
	return matlab_function(self,*arg,**kwargs)

class matlab_function:
    def __call__(self, *arg, **kwargs):
        self._matlab._lock.acquire()
        try:
            _nout = self._nout
            if kwargs:
                for key,value in kwargs.iteritems():
                    if key=='nout': _nout = value
                    else: raise ValueError,"Unexpected argument %s"%key
	    _nin = len(arg)
            for i in range(_nin):
                self._matlab['in%d' % i]=arg[i]
            command = ( (_nout>1)*'[ '
			+",".join(['out%d' % i for i in range(_nout)])
			+ (_nout>1)*' ]'
                        + (_nout>0)*" = "
			+ self._name
			+ (_nin>0)*"("
                        +",".join(['in%d' %i for i in range(_nin)])
			+ (_nin>0)*")" )
            self._matlab(command)
            if _nout == 1:
                return self._matlab['out0']
            elif _nout > 1:
                return tuple([self._matlab['out%d' % i] for i in range(_nout)])
        finally: self._matlab._lock.release()

    def __init__(self, matlabobj, name, nout=0):
	self._matlab = matlabobj
	self._nout = nout
	self._name = name
    
M = matlab(defer=1)
initM = M.changestartcmd