# -------------------------------------------------------------------------------
# Copyright IBM Corp. 2017
# 
# Licensed under the Apache License, Version 2.0 (the 'License');
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# 
# http://www.apache.org/licenses/LICENSE-2.0
# 
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an 'AS IS' BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# -------------------------------------------------------------------------------

from pixiedust.display.chart.renderers import PixiedustRenderer
from pixiedust.display.chart.renderers.baseChartDisplay import commonChartOptions
from pixiedust.utils import Logger
from .bokehBaseDisplay import BokehBaseDisplay
from bokeh.plotting import figure
import numpy as np
import math
import sys

@PixiedustRenderer(id="histogram")
@Logger()
class BKHistogramRenderer(BokehBaseDisplay):
    def supportsAggregation(self, handlerId):
        return False

    def supportsKeyFields(self, handlerId):
        return False
    
    def getPreferredDefaultValueFieldCount(self, handlerId):
        return 1

    def getDefaultKeyFields(self, handlerId, aggregation):
        return []

    def acceptOption(self, optionName):
        if optionName == 'histoChartType':
            return False
        return True

    @commonChartOptions
    def getChartOptions(self):
        return [
            { 'name': 'color',
              'metadata': {
                    'type': "dropdown",
                    'values': ["None"] + self.getFieldNames(),
                    'default': ""
                }
            }
        ]

    def canRenderChart(self):
        return (True, None)

    def getExtraFields(self):
        color = self.options.get("color")
        return [color] if color is not None else []

    def createBokehChart(self):
        defaultbin = math.sqrt(len(self.getWorkingPandasDataFrame().index))
        binsize = int(self.options.get('binsize', defaultbin))
        valueFields = self.getValueFields()
        colour = self.options.get("color")

        def histogram(df, vField, color=None, clustered=None):
            colors = self.colorPalette(len(df.index)) if color is None else color

            p = figure(y_axis_label='Frequency', x_axis_label=vField)

            for j,c in enumerate(list(df[clustered].unique())) if clustered else enumerate([None]):
                df2 = df[df[clustered] == c] if c else df
                hist, edges = np.histogram(list(df2[vField]), density=True, bins=binsize)
                p.quad(top=hist, bottom=0, left=edges[:-1], right=edges[1:], fill_color=colors[j], line_color="#cccccc", fill_alpha=0.8 if clustered else 1, legend=str(c) if clustered else None)

            p.y_range.start=0

            p.legend.location = "top_left"
            return p

        charts = []
        wpdf = self.getWorkingPandasDataFrame().copy()
        colours = self.colorPalette(None if colour is None else len(wpdf[colour].unique()))
        
        for i, v in enumerate(valueFields):
            charts.append(histogram(wpdf, v, color=colours, clustered=colour))


        return charts

