import random

from AnyQt.QtCore import Qt
from AnyQt.QtWidgets import QSizePolicy

from Orange.data import Table
from Orange.preprocess import Randomize
from Orange.widgets.settings import Setting
from Orange.widgets.utils.widgetpreview import WidgetPreview
from Orange.widgets.utils.state_summary import format_summary_details
from Orange.widgets.widget import OWWidget, Input, Output
from Orange.widgets import gui


class OWRandomize(OWWidget):
    name = "Randomize"
    description = "Randomize features, class and/or metas in data table."
    icon = "icons/Random.svg"
    priority = 2100
    keywords = []

    class Inputs:
        data = Input("Data", Table)

    class Outputs:
        data = Output("Data", Table)

    resizing_enabled = False
    want_main_area = False

    shuffle_class = Setting(True)
    shuffle_attrs = Setting(False)
    shuffle_metas = Setting(False)
    scope_prop = Setting(80)
    random_seed = Setting(False)
    auto_apply = Setting(True)

    def __init__(self):
        super().__init__()
        self.data = None

        # GUI
        box = gui.hBox(self.controlArea, "Shuffled columns")
        box.layout().setSpacing(20)
        self.class_check = gui.checkBox(
            box, self, "shuffle_class", "Classes",
            callback=self._shuffle_check_changed)
        self.attrs_check = gui.checkBox(
            box, self, "shuffle_attrs", "Features",
            callback=self._shuffle_check_changed)
        self.metas_check = gui.checkBox(
            box, self, "shuffle_metas", "Metas",
            callback=self._shuffle_check_changed)

        box = gui.vBox(self.controlArea, "Shuffled rows")
        hbox = gui.hBox(box)
        gui.widgetLabel(hbox, "None")
        self.scope_slider = gui.hSlider(
            hbox, self, "scope_prop", minValue=0, maxValue=100, width=140,
            createLabel=False, callback=self._scope_slider_changed)
        gui.widgetLabel(hbox, "All")
        self.scope_label = gui.widgetLabel(
            box, "", alignment=Qt.AlignCenter,
            sizePolicy=(QSizePolicy.MinimumExpanding, QSizePolicy.Fixed))
        self._set_scope_label()
        self.replicable_check = gui.checkBox(
            box, self, "random_seed", "Replicable shuffling",
            callback=self._shuffle_check_changed)

        self.info.set_input_summary(self.info.NoInput)
        self.info.set_output_summary(self.info.NoOutput)

        gui.auto_apply(self.buttonsArea, self, commit=self.apply)

    @property
    def parts(self):
        return [self.shuffle_class, self.shuffle_attrs, self.shuffle_metas]

    def _shuffle_check_changed(self):
        self.apply()

    def _scope_slider_changed(self):
        self._set_scope_label()
        self.apply()

    def _set_scope_label(self):
        self.scope_label.setText("{}%".format(self.scope_prop))

    @Inputs.data
    def set_data(self, data):
        self.data = data
        summary = len(data) if data else self.info.NoInput
        details = format_summary_details(data) if data else ""
        self.info.set_input_summary(summary, details)
        self.unconditional_apply()

    def apply(self):
        data = None
        if self.data:
            rand_seed = self.random_seed or None
            size = int(len(self.data) * self.scope_prop / 100)
            random.seed(rand_seed)
            indices = sorted(random.sample(range(len(self.data)), size))
            type_ = sum(t for t, p in zip(Randomize.Type, self.parts) if p)
            randomized = Randomize(type_, rand_seed)(self.data[indices])
            data = self.data.copy()
            for i, instance in zip(indices, randomized):
                data[i] = instance
        summary = len(data) if data else self.info.NoOutput
        details = format_summary_details(data) if data else ""
        self.info.set_output_summary(summary, details)
        self.Outputs.data.send(data)

    def send_report(self):
        labels = ["classes", "features", "metas"]
        include = [label for label, i in zip(labels, self.parts) if i]
        text = "none" if not include else \
            " and ".join(filter(None, (", ".join(include[:-1]), include[-1])))
        self.report_items(
            "Settings",
            [("Shuffled columns", text),
             ("Proportion of shuffled rows", "{}%".format(self.scope_prop)),
             ("Replicable", "yes" if self.random_seed else "no")])


if __name__ == "__main__":  # pragma: no cover
    WidgetPreview(OWRandomize).run(Table("iris"))
