import os

import numpy as np

from bumps import fitters
from bumps.names import load_problem

SEED = 1


def example_dir():
    """
    Return the directory containing the rst file source for the current plot.
    """
    # Search through the call stack for the rstdir variable.
    #
    # This is an ugly hack which relies on internal structures of the python
    # interpreter and particular variables used in internal functions from
    # the matplotlib plot directive, and so is likely to break.
    #
    # If this code breaks, you could probably get away with searching up
    # the stack for the variable 'state_machine', which is a sphinx defined
    # variable, and use:
    #
    #  rstdir, _ = os.path.split(state_machine.document.attributes['source'])
    #
    # Even better would be to modify the plot directive to make rstdir
    # available to the inline plot directive, e.g., by adding it to the
    # locals context.  It is already implicitly available to the plot
    # file context because there is an explicit chdir to the directory
    # containing the plot.
    import inspect

    frame = inspect.currentframe()
    RSTDIR = "rst_dir"
    while frame and RSTDIR not in frame.f_locals:
        frame = frame.f_back
        # print "checking",frame.f_code.co_name
    if not frame:
        raise RuntimeError("plot directive changed: %r no longer defined" % RSTDIR)
    return frame.f_locals[RSTDIR] if frame else ""


def plot_model(filename):
    from matplotlib import pyplot as plt

    # import sys; print >>sys.stderr, "in plot with",filename, example_dir()
    np.random.seed(SEED)
    p = load_problem(os.path.join(example_dir(), filename))
    p.plot()
    plt.show()


def fit_model(filename):
    from matplotlib import pyplot as plt

    # import sys; print >>sys.stderr, "in plot with",filename, example_dir()
    np.random.seed(SEED)
    problem = load_problem(os.path.join(example_dir(), filename))
    # x, fx = fit.RLFit(problem).solve(steps=1000, burn=99)
    # x, fx = fit.DEFit(problem).solve(steps=200, pop=10)
    # x, fx = fit.PTFit(problem).solve(steps=100,burn=400)
    # x, fx = fit.BFGSFit(problem).solve(steps=200)
    # x, fx = fit.SimplexFit(problem).solve(steps=1000)
    result = fitters.fit(problem, method="amoeba", verbose=False, steps=1000)
    chisq = problem(result.x)
    print("chisq=%g" % chisq)
    if chisq > 2:
        raise RuntimeError("Fit did not converge")
    problem.plot()
    plt.show()
