import warnings

import numpy as np

from .core import load_model_definition, load_model, make_kernel
from .core import call_kernel, call_ER, call_VR

class DirectModel:
    def __init__(self, name, q_vectors=None, dtype='single'):
        self.model_definition = load_model_definition(name)
        self.model = load_model(self.model_definition, dtype=dtype)
        if q_vectors is not None:
            q_vectors = [np.ascontiguousarray(q,dtype=dtype) for q in q_vectors]
            self.kernel = make_kernel(self.model, q_vectors)
    def __call__(self, **pars):
        return call_kernel(self.kernel, pars)
    def ER(self, **pars):
        return call_ER(self.model.info, pars)
    def VR(self, **pars):
        return call_VR(self.model.info, pars)

def demo():
    import sys
    if len(sys.argv) < 3:
        print "usage: python -m sasmodels.direct_model modelname (q|qx,qy) par=val ..."
        sys.exit(1)
    model_name = sys.argv[1]
    call = sys.argv[2].upper()
    if call in ("ER","VR"):
        q_vectors = None
    else:
        values = [float(v) for v in sys.argv[2].split(',')]
        if len(values) == 1:
            q = values[0]
            q_vectors = [[q]]
        elif len(values) == 2:
            qx,qy = values
            q_vectors = [[qx],[qy]]
        else:
            print "use q or qx,qy or ER or VR"
            sys.exit(1)
    model = DirectModel(model_name, q_vectors)
    pars = dict((k,float(v))
                for pair in sys.argv[3:]
                for k,v in [pair.split('=')])
    if call == "ER":
        print model.ER(**pars)
    elif call == "VR":
        print model.VR(**pars)
    else:
        Iq = model(**pars)
        print Iq[0]

if __name__ == "__main__":
    demo()