# coding: utf-8
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# Copyright (c) 2004-2021 European Synchrotron Radiation Facility
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# This file is part of the PyMca X-ray Fluorescence Toolkit developed at
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"""This module provides a widget designed to configure and run a fitting
process with constraints on parameters.

The main class is :class:`FitWidget`. It relies on
:mod:`silx.math.fit.fitmanager`, which relies on :func:`silx.math.fit.leastsq`.

The user can choose between functions before running the fit. These function can
be user defined, or by default are loaded from
:mod:`silx.math.fit.fittheories`.
"""

__authors__ = ["V.A. Sole", "P. Knobel"]
__license__ = "MIT"
__date__ = "17/07/2018"

import logging
import sys
import traceback

from silx.math.fit import fittheories
from silx.math.fit import fitmanager, functions
from silx.gui import qt
from .FitWidgets import (FitActionsButtons, FitStatusLines,
                         FitConfigWidget, ParametersTab)
from .FitConfig import getFitConfigDialog
from .BackgroundWidget import getBgDialog, BackgroundDialog
from ...utils.deprecation import deprecated

DEBUG = 0
_logger = logging.getLogger(__name__)


__authors__ = ["V.A. Sole", "P. Knobel"]
__license__ = "MIT"
__date__ = "30/11/2016"


class FitWidget(qt.QWidget):
    """This widget can be used to configure, run and display results of a
    fitting process.

    The standard steps for using this widget is to initialize it, then load
    the data to be fitted.

    Optionally, you can also load user defined fit theories. If you skip this
    step, a series of default fit functions will be presented (gaussian-like
    functions), and you can later load your custom fit theories from an
    external file using the GUI.

    A fit theory is a fit function and its associated features:

      - estimation function,
      - list of parameter names
      - numerical derivative algorithm
      - configuration widget

    Once the widget is up and running, the user may select a fit theory and a
    background theory, change configuration parameters specific to the theory
    run the estimation, set constraints on parameters and run the actual fit.

    The results are displayed in a table.

    .. image:: img/FitWidget.png
    """
    sigFitWidgetSignal = qt.Signal(object)
    """This signal is emitted by the estimation and fit methods.
    It carries a dictionary with two items:

        - *event*: one of the following strings

            - *EstimateStarted*,
            - *FitStarted*
            - *EstimateFinished*,
            - *FitFinished*
            - *EstimateFailed*
            - *FitFailed*

        - *data*: None, or fit/estimate results (see documentation for
          :attr:`silx.math.fit.fitmanager.FitManager.fit_results`)
    """

    def __init__(self, parent=None, title=None, fitmngr=None,
                 enableconfig=True, enablestatus=True, enablebuttons=True):
        """

        :param parent: Parent widget
        :param title: Window title
        :param fitmngr: User defined instance of
            :class:`silx.math.fit.fitmanager.FitManager`, or ``None``
        :param enableconfig: If ``True``, activate widgets to modify the fit
            configuration (select between several fit functions or background
            functions, apply global constraints, peak search parameters…)
        :param enablestatus: If ``True``, add a fit status widget, to display
            a message when fit estimation is available and when fit results
            are available, as well as a measure of the fit error.
        :param enablebuttons: If ``True``, add buttons to run estimation and
            fitting.
        """
        if title is None:
            title = "FitWidget"
        qt.QWidget.__init__(self, parent)

        self.setWindowTitle(title)
        layout = qt.QVBoxLayout(self)

        self.fitmanager = self._setFitManager(fitmngr)
        """Instance of :class:`FitManager`.
        This is the underlying data model of this FitWidget.

        If no custom theories are defined, the default ones from
        :mod:`silx.math.fit.fittheories` are imported.
        """

        # reference fitmanager.configure method for direct access
        self.configure = self.fitmanager.configure
        self.fitconfig = self.fitmanager.fitconfig

        self.configdialogs = {}
        """This dictionary defines the fit configuration widgets
        associated with the fit theories in :attr:`fitmanager.theories`

        Keys must correspond to existing theory names, i.e. existing keys
        in :attr:`fitmanager.theories`.

        Values must be instances of QDialog widgets with an additional
        *output* attribute, a dictionary storing configuration parameters
        interpreted by the corresponding fit theory.

        The dialog can also define a *setDefault* method to initialize the
        widget values with values in a dictionary passed as a parameter.
        This will be executed first.

        In case the widget does not actually inherit :class:`QDialog`, it
        must at least implement the following methods (executed in this
        particular order):

            - :meth:`show`: should cause the widget to become visible to the
              user)
            - :meth:`exec`: should run while the user is interacting with the
              widget, interrupting the rest of the program. It should
              typically end (*return*) when the user clicks an *OK*
              or a *Cancel* button.
            - :meth:`result`: must return ``True`` if the new configuration in
              attribute :attr:`output` is to be accepted (user clicked *OK*),
              or return ``False`` if :attr:`output` is to be rejected (user
              clicked *Cancel*)

        To associate a custom configuration widget with a fit theory, use
        :meth:`associateConfigDialog`. E.g.::

            fw = FitWidget()
            my_config_widget = MyGaussianConfigWidget(parent=fw)
            fw.associateConfigDialog(theory_name="Gaussians",
                                     config_widget=my_config_widget)
        """

        self.bgconfigdialogs = {}
        """Same as :attr:`configdialogs`, except that the widget is associated
        with a background theory in :attr:`fitmanager.bgtheories`"""

        self._associateDefaultConfigDialogs()

        self.guiConfig = None
        """Configuration widget at the top of FitWidget, to select
        fit function, background function, and open an advanced
        configuration dialog."""

        self.guiParameters = ParametersTab(self)
        """Table widget for display of fit parameters and constraints"""

        if enableconfig:
            self.guiConfig = FitConfigWidget(self)
            """Function selector and configuration widget"""

            self.guiConfig.FunConfigureButton.clicked.connect(
                self.__funConfigureGuiSlot)
            self.guiConfig.BgConfigureButton.clicked.connect(
                self.__bgConfigureGuiSlot)

            self.guiConfig.WeightCheckBox.setChecked(
                    self.fitconfig.get("WeightFlag", False))
            self.guiConfig.WeightCheckBox.stateChanged[int].connect(self.weightEvent)

            if qt.BINDING in ('PySide2', 'PyQt5'):
                self.guiConfig.BkgComBox.activated[str].connect(self.bkgEvent)
                self.guiConfig.FunComBox.activated[str].connect(self.funEvent)
            else:  # Qt6
                self.guiConfig.BkgComBox.textActivated.connect(self.bkgEvent)
                self.guiConfig.FunComBox.textActivated.connect(self.funEvent)

            self._populateFunctions()

            layout.addWidget(self.guiConfig)

        layout.addWidget(self.guiParameters)

        if enablestatus:
            self.guistatus = FitStatusLines(self)
            """Status bar"""
            layout.addWidget(self.guistatus)

        if enablebuttons:
            self.guibuttons = FitActionsButtons(self)
            """Widget with estimate, start fit and dismiss buttons"""
            self.guibuttons.EstimateButton.clicked.connect(self.estimate)
            self.guibuttons.EstimateButton.setEnabled(False)
            self.guibuttons.StartFitButton.clicked.connect(self.startFit)
            self.guibuttons.StartFitButton.setEnabled(False)
            self.guibuttons.DismissButton.clicked.connect(self.dismiss)
            layout.addWidget(self.guibuttons)

    def _setFitManager(self, fitinstance):
        """Initialize a :class:`FitManager` instance, to be assigned to
        :attr:`fitmanager`, or use a custom FitManager instance.

        :param fitinstance: Existing instance of FitManager, possibly
            customized by the user, or None to load a default instance."""
        if isinstance(fitinstance, fitmanager.FitManager):
            # customized
            fitmngr = fitinstance
        else:
            # initialize default instance
            fitmngr = fitmanager.FitManager()

        # initialize the default fitting functions in case
        # none is present
        if not len(fitmngr.theories):
            fitmngr.loadtheories(fittheories)

        return fitmngr

    def _associateDefaultConfigDialogs(self):
        """Fill :attr:`bgconfigdialogs` and :attr:`configdialogs` by calling
        :meth:`associateConfigDialog` with default config dialog widgets.
        """
        # associate silx.gui.fit.FitConfig with all theories
        # Users can later associate their own custom dialogs to
        # replace the default.
        configdialog = getFitConfigDialog(parent=self,
                                          default=self.fitconfig)
        for theory in self.fitmanager.theories:
            self.associateConfigDialog(theory, configdialog)
        for bgtheory in self.fitmanager.bgtheories:
            self.associateConfigDialog(bgtheory, configdialog,
                                       theory_is_background=True)

        # associate silx.gui.fit.BackgroundWidget with Strip and Snip
        bgdialog = getBgDialog(parent=self,
                               default=self.fitconfig)
        for bgtheory in ["Strip", "Snip"]:
            if bgtheory in self.fitmanager.bgtheories:
                self.associateConfigDialog(bgtheory, bgdialog,
                                           theory_is_background=True)

    def _populateFunctions(self):
        """Fill combo-boxes with fit theories and background theories
        loaded by :attr:`fitmanager`.
        Run :meth:`fitmanager.configure` to ensure the custom configuration
        of the selected theory has been loaded into :attr:`fitconfig`"""
        for theory_name in self.fitmanager.bgtheories:
            self.guiConfig.BkgComBox.addItem(theory_name)
            self.guiConfig.BkgComBox.setItemData(
                    self.guiConfig.BkgComBox.findText(theory_name),
                    self.fitmanager.bgtheories[theory_name].description,
                    qt.Qt.ToolTipRole)

        for theory_name in self.fitmanager.theories:
            self.guiConfig.FunComBox.addItem(theory_name)
            self.guiConfig.FunComBox.setItemData(
                    self.guiConfig.FunComBox.findText(theory_name),
                    self.fitmanager.theories[theory_name].description,
                    qt.Qt.ToolTipRole)

        # - activate selected fit theory (if any)
        #    - activate selected bg theory (if any)
        configuration = self.fitmanager.configure()
        if self.fitmanager.selectedtheory is None:
            # take the first one by default
            self.guiConfig.FunComBox.setCurrentIndex(1)
            self.funEvent(list(self.fitmanager.theories.keys())[0])
        else:
            idx = list(self.fitmanager.theories).index(self.fitmanager.selectedtheory)
            self.guiConfig.FunComBox.setCurrentIndex(idx + 1)
            self.funEvent(self.fitmanager.selectedtheory)

        if self.fitmanager.selectedbg is None:
            self.guiConfig.BkgComBox.setCurrentIndex(1)
            self.bkgEvent(list(self.fitmanager.bgtheories.keys())[0])
        else:
            idx = list(self.fitmanager.bgtheories).index(self.fitmanager.selectedbg)
            self.guiConfig.BkgComBox.setCurrentIndex(idx + 1)
            self.bkgEvent(self.fitmanager.selectedbg)

        configuration.update(self.configure())

    @deprecated(replacement='setData', since_version='0.3.0')
    def setdata(self, x, y, sigmay=None, xmin=None, xmax=None):
        self.setData(x, y, sigmay, xmin, xmax)

    def setData(self, x=None, y=None, sigmay=None, xmin=None, xmax=None):
        """Set data to be fitted.

        :param x: Abscissa data. If ``None``, :attr:`xdata`` is set to
            ``numpy.array([0.0, 1.0, 2.0, ..., len(y)-1])``
        :type x: Sequence or numpy array or None
        :param y: The dependant data ``y = f(x)``. ``y`` must have the same
            shape as ``x`` if ``x`` is not ``None``.
        :type y: Sequence or numpy array or None
        :param sigmay: The uncertainties in the ``ydata`` array. These are
            used as weights in the least-squares problem.
            If ``None``, the uncertainties are assumed to be 1.
        :type sigmay: Sequence or numpy array or None
        :param xmin: Lower value of x values to use for fitting
        :param xmax: Upper value of x values to use for fitting
        """
        if y is None:
            self.guibuttons.EstimateButton.setEnabled(False)
            self.guibuttons.StartFitButton.setEnabled(False)
        else:
            self.guibuttons.EstimateButton.setEnabled(True)
            self.guibuttons.StartFitButton.setEnabled(True)
            self.fitmanager.setdata(x=x, y=y, sigmay=sigmay,
                                    xmin=xmin, xmax=xmax)
            for config_dialog in self.bgconfigdialogs.values():
                if isinstance(config_dialog, BackgroundDialog):
                    config_dialog.setData(x, y, xmin=xmin, xmax=xmax)

    def associateConfigDialog(self, theory_name, config_widget,
                              theory_is_background=False):
        """Associate an instance of custom configuration dialog widget to
        a fit theory or to a background theory.

        This adds or modifies an item in the correspondence table
        :attr:`configdialogs` or :attr:`bgconfigdialogs`.

        :param str theory_name: Name of fit theory. This must be a key of dict
            :attr:`fitmanager.theories`
        :param config_widget: Custom configuration widget. See documentation
            for :attr:`configdialogs`
        :param bool theory_is_background: If flag is *True*, add dialog to
            :attr:`bgconfigdialogs` rather than :attr:`configdialogs`
            (default).
        :raise: KeyError if parameter ``theory_name`` does not match an
            existing fit theory or background theory in :attr:`fitmanager`.
        :raise: AttributeError if the widget does not implement the mandatory
            methods (*show*, *exec*, *result*, *setDefault*) or the mandatory
            attribute (*output*).
        """
        theories = self.fitmanager.bgtheories if theory_is_background else\
            self.fitmanager.theories

        if theory_name not in theories:
            raise KeyError("%s does not match an existing fitmanager theory")

        if config_widget is not None:
            if (not hasattr(config_widget, "exec") and
                    not hasattr(config_widget, "exec_")):
                raise AttributeError(
                    "Custom configuration widget must define exec or exec_")

            for mandatory_attr in ["show", "result", "output"]:
                if not hasattr(config_widget, mandatory_attr):
                    raise AttributeError(
                            "Custom configuration widget must define " +
                            "attribute or method " + mandatory_attr)

        if theory_is_background:
            self.bgconfigdialogs[theory_name] = config_widget
        else:
            self.configdialogs[theory_name] = config_widget

    def _emitSignal(self, ddict):
        """Emit pyqtSignal after estimation completed
        (``ddict = {'event': 'EstimateFinished', 'data': fit_results}``)
        and after fit completed
        (``ddict = {'event': 'FitFinished', 'data': fit_results}``)"""
        self.sigFitWidgetSignal.emit(ddict)

    def __funConfigureGuiSlot(self):
        """Open an advanced configuration dialog widget"""
        self.__configureGui(dialog_type="function")

    def __bgConfigureGuiSlot(self):
        """Open an advanced configuration dialog widget"""
        self.__configureGui(dialog_type="background")

    def __configureGui(self, newconfiguration=None, dialog_type="function"):
        """Open an advanced configuration dialog widget to get a configuration
        dictionary, or use a supplied configuration dictionary. Call
        :meth:`configure` with this dictionary as a parameter. Update the gui
        accordingly. Reinitialize the fit results in the table and in
        :attr:`fitmanager`.

        :param newconfiguration: User supplied configuration dictionary. If ``None``,
            open a dialog widget that returns a dictionary."""
        configuration = self.configure()
        # get new dictionary
        if newconfiguration is None:
            newconfiguration = self.configureDialog(configuration, dialog_type)
        # update configuration
        configuration.update(self.configure(**newconfiguration))
        # set fit function theory
        try:
            i = 1 + \
                list(self.fitmanager.theories.keys()).index(
                        self.fitmanager.selectedtheory)
            self.guiConfig.FunComBox.setCurrentIndex(i)
            self.funEvent(self.fitmanager.selectedtheory)
        except ValueError:
            _logger.error("Function not in list %s",
                          self.fitmanager.selectedtheory)
            self.funEvent(list(self.fitmanager.theories.keys())[0])
        # current background
        try:
            i = 1 + \
                list(self.fitmanager.bgtheories.keys()).index(
                        self.fitmanager.selectedbg)
            self.guiConfig.BkgComBox.setCurrentIndex(i)
            self.bkgEvent(self.fitmanager.selectedbg)
        except ValueError:
            _logger.error("Background not in list %s",
                          self.fitmanager.selectedbg)
            self.bkgEvent(list(self.fitmanager.bgtheories.keys())[0])

        # update the Gui
        self.__initialParameters()

    def configureDialog(self, oldconfiguration, dialog_type="function"):
        """Display a dialog, allowing the user to define fit configuration
        parameters.

        By default, a common dialog is used for all fit theories. But if the
        defined a custom dialog using :meth:`associateConfigDialog`, it is
        used instead.

        :param dict oldconfiguration: Dictionary containing previous configuration
        :param str dialog_type: "function" or "background"
        :return: User defined parameters in a dictionary
        """
        newconfiguration = {}
        newconfiguration.update(oldconfiguration)

        if dialog_type == "function":
            theory = self.fitmanager.selectedtheory
            configdialog = self.configdialogs[theory]
        elif dialog_type == "background":
            theory = self.fitmanager.selectedbg
            configdialog = self.bgconfigdialogs[theory]

        # this should only happen if a user specifically associates None
        # with a theory, to have no configuration option
        if configdialog is None:
            return {}

        # update state of configdialog before showing it
        if hasattr(configdialog, "setDefault"):
            configdialog.setDefault(newconfiguration)
        configdialog.show()
        if hasattr(configdialog, "exec"):
            configdialog.exec()
        else:  # Qt5 compatibility
            configdialog.exec_()
        if configdialog.result():
            newconfiguration.update(configdialog.output)

        return newconfiguration

    def estimate(self):
        """Run parameter estimation function then emit
        :attr:`sigFitWidgetSignal` with a dictionary containing a status
        message and a list of fit parameters estimations
        in the format defined in
        :attr:`silx.math.fit.fitmanager.FitManager.fit_results`

        The emitted dictionary has an *"event"* key that can have
        following values:

            - *'EstimateStarted'*
            - *'EstimateFailed'*
            - *'EstimateFinished'*
        """
        try:
            theory_name = self.fitmanager.selectedtheory
            estimation_function = self.fitmanager.theories[theory_name].estimate
            if estimation_function is not None:
                ddict = {'event': 'EstimateStarted',
                         'data': None}
                self._emitSignal(ddict)
                self.fitmanager.estimate(callback=self.fitStatus)
            else:
                msg = qt.QMessageBox(self)
                msg.setIcon(qt.QMessageBox.Information)
                text = "Function does not define a way to estimate\n"
                text += "the initial parameters. Please, fill them\n"
                text += "yourself in the table and press Start Fit\n"
                msg.setText(text)
                msg.setWindowTitle('FitWidget Message')
                msg.exec()
                return
        except Exception as e:    # noqa (we want to catch and report all errors)
            _logger.warning('Estimate error: %s', traceback.format_exc())
            msg = qt.QMessageBox(self)
            msg.setIcon(qt.QMessageBox.Critical)
            msg.setWindowTitle("Estimate Error")
            msg.setText("Error on estimate: %s" % e)
            msg.exec()
            ddict = {
                'event': 'EstimateFailed',
                'data': None}
            self._emitSignal(ddict)
            return

        self.guiParameters.fillFromFit(
            self.fitmanager.fit_results, view='Fit')
        self.guiParameters.removeAllViews(keep='Fit')
        ddict = {
            'event': 'EstimateFinished',
            'data': self.fitmanager.fit_results}
        self._emitSignal(ddict)

    @deprecated(replacement='startFit', since_version='0.3.0')
    def startfit(self):
        self.startFit()

    def startFit(self):
        """Run fit, then emit :attr:`sigFitWidgetSignal` with a dictionary
        containing a status message and a list of fit
        parameters results in the format defined in
        :attr:`silx.math.fit.fitmanager.FitManager.fit_results`

        The emitted dictionary has an *"event"* key that can have
        following values:

            - *'FitStarted'*
            - *'FitFailed'*
            - *'FitFinished'*
        """
        self.fitmanager.fit_results = self.guiParameters.getFitResults()
        try:
            ddict = {'event': 'FitStarted',
                     'data': None}
            self._emitSignal(ddict)
            self.fitmanager.runfit(callback=self.fitStatus)
        except Exception as e:  # noqa (we want to catch and report all errors)
            _logger.warning('Estimate error: %s', traceback.format_exc())
            msg = qt.QMessageBox(self)
            msg.setIcon(qt.QMessageBox.Critical)
            msg.setWindowTitle("Fit Error")
            msg.setText("Error on Fit: %s" % e)
            msg.exec()
            ddict = {
                'event': 'FitFailed',
                'data': None
            }
            self._emitSignal(ddict)
            return

        self.guiParameters.fillFromFit(
            self.fitmanager.fit_results, view='Fit')
        self.guiParameters.removeAllViews(keep='Fit')
        ddict = {
            'event': 'FitFinished',
            'data': self.fitmanager.fit_results
        }
        self._emitSignal(ddict)
        return

    def bkgEvent(self, bgtheory):
        """Select background theory, then reinitialize parameters"""
        bgtheory = str(bgtheory)
        if bgtheory in self.fitmanager.bgtheories:
            self.fitmanager.setbackground(bgtheory)
        else:
            functionsfile = qt.QFileDialog.getOpenFileName(
                self, "Select python module with your function(s)", "",
                "Python Files (*.py);;All Files (*)")

            if len(functionsfile):
                try:
                    self.fitmanager.loadbgtheories(functionsfile)
                except ImportError:
                    qt.QMessageBox.critical(self, "ERROR",
                                            "Function not imported")
                    return
                else:
                    # empty the ComboBox
                    while self.guiConfig.BkgComBox.count() > 1:
                        self.guiConfig.BkgComBox.removeItem(1)
                    # and fill it again
                    for key in self.fitmanager.bgtheories:
                        self.guiConfig.BkgComBox.addItem(str(key))

            i = 1 + \
                list(self.fitmanager.bgtheories.keys()).index(
                    self.fitmanager.selectedbg)
            self.guiConfig.BkgComBox.setCurrentIndex(i)
        self.__initialParameters()

    def funEvent(self, theoryname):
        """Select a fit theory to be used for fitting. If this theory exists
        in :attr:`fitmanager`, use it. Then, reinitialize table.

        :param theoryname: Name of the fit theory to use for fitting. If this theory
            exists in :attr:`fitmanager`, use it. Else, open a file dialog to open
            a custom fit function definition file with
            :meth:`fitmanager.loadtheories`.
        """
        theoryname = str(theoryname)
        if theoryname in self.fitmanager.theories:
            self.fitmanager.settheory(theoryname)
        else:
            # open a load file dialog
            functionsfile = qt.QFileDialog.getOpenFileName(
                self, "Select python module with your function(s)", "",
                "Python Files (*.py);;All Files (*)")

            if len(functionsfile):
                try:
                    self.fitmanager.loadtheories(functionsfile)
                except ImportError:
                    qt.QMessageBox.critical(self, "ERROR",
                                            "Function not imported")
                    return
                else:
                    # empty the ComboBox
                    while self.guiConfig.FunComBox.count() > 1:
                        self.guiConfig.FunComBox.removeItem(1)
                    # and fill it again
                    for key in self.fitmanager.theories:
                        self.guiConfig.FunComBox.addItem(str(key))

            i = 1 + \
                list(self.fitmanager.theories.keys()).index(
                    self.fitmanager.selectedtheory)
            self.guiConfig.FunComBox.setCurrentIndex(i)
        self.__initialParameters()

    def weightEvent(self, flag):
        """This is called when WeightCheckBox is clicked, to configure the
        *WeightFlag* field in :attr:`fitmanager.fitconfig` and set weights
        in the least-square problem."""
        self.configure(WeightFlag=flag)
        if flag:
            self.fitmanager.enableweight()
        else:
            # set weights back to 1
            self.fitmanager.disableweight()

    def __initialParameters(self):
        """Fill the fit parameters names with names of the parameters of
        the selected background theory and the selected fit theory.
        Initialize :attr:`fitmanager.fit_results` with these names, and
        initialize the table with them. This creates a view called "Fit"
        in :attr:`guiParameters`"""
        self.fitmanager.parameter_names = []
        self.fitmanager.fit_results = []
        for pname in self.fitmanager.bgtheories[self.fitmanager.selectedbg].parameters:
            self.fitmanager.parameter_names.append(pname)
            self.fitmanager.fit_results.append({'name': pname,
                                           'estimation': 0,
                                           'group': 0,
                                           'code': 'FREE',
                                           'cons1': 0,
                                           'cons2': 0,
                                           'fitresult': 0.0,
                                           'sigma': 0.0,
                                           'xmin': None,
                                           'xmax': None})
        if self.fitmanager.selectedtheory is not None:
            theory = self.fitmanager.selectedtheory
            for pname in self.fitmanager.theories[theory].parameters:
                self.fitmanager.parameter_names.append(pname + "1")
                self.fitmanager.fit_results.append({'name': pname + "1",
                                               'estimation': 0,
                                               'group': 1,
                                               'code': 'FREE',
                                               'cons1': 0,
                                               'cons2': 0,
                                               'fitresult': 0.0,
                                               'sigma': 0.0,
                                               'xmin': None,
                                               'xmax': None})

        self.guiParameters.fillFromFit(
            self.fitmanager.fit_results, view='Fit')

    def fitStatus(self, data):
        """Set *status* and *chisq* in status bar"""
        if 'chisq' in data:
            if data['chisq'] is None:
                self.guistatus.ChisqLine.setText(" ")
            else:
                chisq = data['chisq']
                self.guistatus.ChisqLine.setText("%6.2f" % chisq)

        if 'status' in data:
            status = data['status']
            self.guistatus.StatusLine.setText(str(status))

    def dismiss(self):
        """Close FitWidget"""
        self.close()


if __name__ == "__main__":
    import numpy

    x = numpy.arange(1500).astype(numpy.float64)
    constant_bg = 3.14

    p = [1000, 100., 30.0,
         500, 300., 25.,
         1700, 500., 35.,
         750, 700., 30.0,
         1234, 900., 29.5,
         302, 1100., 30.5,
         75, 1300., 21.]
    y = functions.sum_gauss(x, *p) + constant_bg

    a = qt.QApplication(sys.argv)
    w = FitWidget()
    w.setData(x=x, y=y)
    w.show()
    a.exec()
