#!/usr/bin/env python
# -*- coding: utf-8 -*-
from __future__ import division

import argparse
from collections import OrderedDict
import numpy as np
import matplotlib
matplotlib.use('Agg')
matplotlib.rcParams['pdf.fonttype'] = 42
matplotlib.rcParams['svg.fonttype'] = 'none'
from deeptools import cm  # noqa: F401
import matplotlib.pyplot as plt
from matplotlib.font_manager import FontProperties
import matplotlib.gridspec as gridspec
from matplotlib import ticker

import sys
import plotly.offline as py
import plotly.graph_objs as go

# own modules
from deeptools import parserCommon
from deeptools import heatmapper
from deeptools.heatmapper_utilities import plot_single, plotly_single
from deeptools.utilities import convertCmap
from deeptools.computeMatrixOperations import filterHeatmapValues

debug = 0
old_settings = np.seterr(all='ignore')
plt.ioff()


def parse_arguments(args=None):
    parser = argparse.ArgumentParser(
        parents=[parserCommon.heatmapperMatrixArgs(),
                 parserCommon.heatmapperOutputArgs(mode='heatmap'),
                 parserCommon.heatmapperOptionalArgs(mode='heatmap')],
        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
        description='This tool creates a heatmap for '
        'scores associated with genomic regions. '
        'The program requires a matrix file '
        'generated by the tool ``computeMatrix``.',
        epilog='An example usage is: plotHeatmap -m <matrix file>',
        add_help=False)

    return parser


def process_args(args=None):
    args = parse_arguments().parse_args(args)

    args.heatmapHeight = args.heatmapHeight if args.heatmapHeight > 3 and args.heatmapHeight <= 100 else 10

    if not matplotlib.colors.is_color_like(args.missingDataColor):
        exit("The value {0}  for --missingDataColor is not valid".format(args.missingDataColor))

    args.boxAroundHeatmaps = True if args.boxAroundHeatmaps == 'yes' else False

    return args


def prepare_layout(hm_matrix, heatmapsize, showSummaryPlot, showColorbar, perGroup, colorbar_position):
    """
    prepare the plot layout
    as a grid having as many rows
    as samples (+1 for colobar)
    and as many rows as groups (or clusters) (+1 for profile plot)
    """
    heatmapwidth, heatmapheight = heatmapsize

    numcols = hm_matrix.get_num_samples()
    numrows = hm_matrix.get_num_groups()
    if perGroup:
        numcols, numrows = numrows, numcols

    # the rows have different size depending
    # on the number of regions contained in the
    if perGroup:
        # heatmap
        height_ratio = np.array([np.amax(np.diff(hm_matrix.group_boundaries))] * numrows)
        # scale ratio to sum = heatmapheight
        height_ratio = heatmapheight * (height_ratio.astype(float) / height_ratio.sum())
    else:
        # heatmap
        height_ratio = np.diff(hm_matrix.group_boundaries)
        # scale ratio to sum = heatmapheight
        height_ratio = heatmapheight * (height_ratio.astype(float) / height_ratio.sum())

    # convert the height_ratio from numpy array back to list
    height_ratio = height_ratio.tolist()
    # the width ratio is equal for all heatmaps
    width_ratio = [heatmapwidth] * numcols

    if showColorbar:
        if colorbar_position == 'below':
            numrows += 2  # a spacer needs to be added to avoid overlaps
            height_ratio += [4 / 2.54]  # spacer
            height_ratio += [1 / 2.54]
        else:
            numcols += 1
            width_ratio += [1 / 2.54]

    if showSummaryPlot:
        numrows += 2  # plus 2 because a spacer is added
        # make height of summary plot
        # proportional to the width of heatmap
        sumplot_height = heatmapwidth
        spacer_height = heatmapwidth / 8
        # scale height_ratios to convert from row
        # numbers to heatmapheigt fractions
        height_ratio = np.concatenate([[sumplot_height, spacer_height], height_ratio])

    grids = gridspec.GridSpec(numrows, numcols, height_ratios=height_ratio, width_ratios=width_ratio)

    return grids


def addProfilePlot(hm, plt, fig, grids, iterNum, iterNum2, perGroup, averageType, plot_type, yAxisLabel, color_list, yMin, yMax, wspace, hspace, colorbar_position, label_rotation=0.0):
    """
    A function to add profile plots to the given figure, possibly in a custom grid subplot which mimics a tight layout (if wspace and hspace are not None)
    """
    if wspace is not None and hspace is not None:
        if colorbar_position == 'side':
            gridsSub = gridspec.GridSpecFromSubplotSpec(1, iterNum, subplot_spec=grids[0, :-1], wspace=wspace, hspace=hspace)
        else:
            gridsSub = gridspec.GridSpecFromSubplotSpec(1, iterNum, subplot_spec=grids[0, :], wspace=wspace, hspace=hspace)

    ax_list = []
    globalYmin = np.inf
    globalYmax = -np.inf
    for sample_id in range(iterNum):
        if perGroup:
            title = hm.matrix.group_labels[sample_id]
            tickIdx = sample_id % hm.matrix.get_num_samples()
        else:
            title = hm.matrix.sample_labels[sample_id]
            tickIdx = sample_id
        if sample_id > 0 and len(yMin) == 1 and len(yMax) == 1:
            ax_profile = fig.add_subplot(grids[0, sample_id])
        else:
            if wspace is not None and hspace is not None:
                ax_profile = fig.add_subplot(gridsSub[0, sample_id])
            else:
                ax_profile = fig.add_subplot(grids[0, sample_id])

        ax_profile.set_title(title)
        for group in range(iterNum2):
            if perGroup:
                sub_matrix = hm.matrix.get_matrix(sample_id, group)
                line_label = sub_matrix['sample']
            else:
                sub_matrix = hm.matrix.get_matrix(group, sample_id)
                line_label = sub_matrix['group']
            plot_single(ax_profile, sub_matrix['matrix'],
                        averageType,
                        color_list[group],
                        line_label,
                        plot_type=plot_type)

        if sample_id > 0 and len(yMin) == 1 and len(yMax) == 1:
            plt.setp(ax_profile.get_yticklabels(), visible=False)

        if sample_id == 0 and yAxisLabel != '':
            ax_profile.set_ylabel(yAxisLabel)
        xticks, xtickslabel = hm.getTicks(tickIdx)
        if np.ceil(max(xticks)) != float(sub_matrix['matrix'].shape[1] - 1):
            tickscale = float(sub_matrix['matrix'].shape[1] - 1) / max(xticks)
            xticks_use = [x * tickscale for x in xticks]
            ax_profile.axes.set_xticks(xticks_use)
        else:
            ax_profile.axes.set_xticks(xticks)
        ax_profile.axes.set_xticklabels(xtickslabel, rotation=label_rotation)
        ax_list.append(ax_profile)

        # align the first and last label
        # such that they don't fall off
        # the heatmap sides
        ticks = ax_profile.xaxis.get_major_ticks()
        ticks[0].label1.set_horizontalalignment('left')
        ticks[-1].label1.set_horizontalalignment('right')

        globalYmin = min(np.float64(globalYmin), ax_profile.get_ylim()[0])
        globalYmax = max(globalYmax, ax_profile.get_ylim()[1])

    # It turns out that set_ylim only takes np.float64s
    for sample_id, subplot in enumerate(ax_list):
        localYMin = yMin[sample_id % len(yMin)]
        localYMax = yMax[sample_id % len(yMax)]
        lims = [globalYmin, globalYmax]
        if localYMin:
            if localYMax:
                lims = (np.float64(localYMin), np.float64(localYMax))
            else:
                lims = (np.float64(localYMin), lims[1])
        elif localYMax:
            lims = (lims[0], np.float64(localYMax))
        if lims[0] >= lims[1]:
            lims = (lims[0], lims[0] + 1)
        ax_list[sample_id].set_ylim(lims)
    return ax_list


def plotlyMatrix(hm,
                 outFilename,
                 yMin=[None], yMax=[None],
                 zMin=[None], zMax=[None],
                 showSummaryPlot=False,
                 cmap=None, colorList=None, colorBarPosition='side',
                 perGroup=False,
                 averageType='median', yAxisLabel='', xAxisLabel='',
                 plotTitle='',
                 showColorbar=False,
                 label_rotation=0.0):
    label_rotation *= -1.0
    if colorBarPosition != 'side':
        sys.error.write("Warning: It is not currently possible to have multiple colorbars with plotly!\n")

    nRows = hm.matrix.get_num_groups()
    nCols = hm.matrix.get_num_samples()
    if perGroup:
        nRows, nCols = nCols, nRows

    profileHeight = 0.0
    profileBottomBuffer = 0.0
    if showSummaryPlot:
        profileHeight = 0.2
        profileBottomBuffer = 0.05
        profileSideBuffer = 0.
        profileWidth = 1. / nCols
        if nCols > 1:
            profileSideBuffer = 0.1 / (nCols - 1)
            profileWidth = 0.9 / nCols

    dataSummary = []
    annos = []
    fig = go.Figure()
    fig['layout'].update(title=plotTitle)
    xAxisN = 1
    yAxisN = 1

    # Summary plots at the top (if appropriate)
    if showSummaryPlot:
        yMinLocal = np.inf
        yMaxLocal = -np.inf
        for i in range(nCols):
            xanchor = 'x{}'.format(xAxisN)
            yanchor = 'y{}'.format(yAxisN)
            xBase = i * (profileSideBuffer + profileWidth)
            yBase = 1 - profileHeight
            xDomain = [xBase, xBase + profileWidth]
            yDomain = [yBase, 1.0]
            for j in range(nRows):
                if perGroup:
                    mat = hm.matrix.get_matrix(i, j)
                    xTicks, xTicksLabels = hm.getTicks(i)
                    label = mat['sample']
                else:
                    mat = hm.matrix.get_matrix(j, i)
                    xTicks, xTicksLabels = hm.getTicks(j)
                    label = mat['group']
                if j == 0:
                    fig['layout']['xaxis{}'.format(xAxisN)] = dict(domain=xDomain, anchor=yanchor, range=[0, mat['matrix'].shape[1]], tickmode='array', tickvals=xTicks, ticktext=xTicksLabels, tickangle=label_rotation)
                    fig['layout']['yaxis{}'.format(yAxisN)] = dict(anchor=xanchor, domain=yDomain)
                trace = plotly_single(mat['matrix'], averageType, colorList[j], label)[0]
                trace.update(xaxis=xanchor, yaxis=yanchor, legendgroup=label)
                if min(trace['y']) < yMinLocal:
                    yMinLocal = min(trace['y'])
                if max(trace['y']) > yMaxLocal:
                    yMaxLocal = max(trace['y'])
                if i == 0:
                    trace.update(showlegend=True)
                dataSummary.append(trace)

            # Add the column label
            if perGroup:
                title = hm.matrix.group_labels[i]
            else:
                title = hm.matrix.sample_labels[i]
            titleX = xBase + 0.5 * profileWidth
            annos.append({'yanchor': 'bottom', 'xref': 'paper', 'xanchor': 'center', 'yref': 'paper', 'text': title, 'y': 1.0, 'x': titleX, 'font': {'size': 16}, 'showarrow': False})
            xAxisN += 1
            yAxisN += 1

        # Adjust y-bounds as appropriate:
        for i in range(1, yAxisN):
            yMinUse = yMinLocal
            if yMin[(i - 1) % len(yMin)] is not None:
                yMinUse = yMin[(i - 1) % len(yMin)]
            yMaxUse = yMaxLocal
            if yMax[(i - 1) % len(yMax)] is not None:
                yMaxUse = yMax[(i - 1) % len(yMax)]
            fig['layout']['yaxis{}'.format(i)].update(range=[yMinUse, yMaxUse])
        fig['layout']['yaxis1'].update(title=yAxisLabel)

    # Add the heatmap
    dataHeatmap = []
    zMinLocal = np.inf
    zMaxLocal = -np.inf
    heatmapWidth = 1. / nCols
    heatmapSideBuffer = 0.0
    if nCols > 1:
        heatmapWidth = .9 / nCols
        heatmapSideBuffer = 0.1 / (nCols - 1)
    heatmapHeight = 1.0 - profileHeight - profileBottomBuffer

    for i in range(nCols):
        xanchor = 'x{}'.format(xAxisN)
        xBase = i * (heatmapSideBuffer + heatmapWidth)

        # Determine the height of each heatmap, they have no buffer
        lengths = [0.0]
        for j in range(nRows):
            if perGroup:
                mat = hm.matrix.get_matrix(i, j)
            else:
                mat = hm.matrix.get_matrix(j, i)
            lengths.append(mat['matrix'].shape[0])
        fractionalHeights = heatmapHeight * np.cumsum(lengths).astype(float) / np.sum(lengths).astype(float)
        xDomain = [xBase, xBase + heatmapWidth]
        fig['layout']['xaxis{}'.format(xAxisN)] = dict(domain=xDomain, anchor='free', position=0.0, range=[0, mat['matrix'].shape[1]], tickmode='array', tickvals=xTicks, ticktext=xTicksLabels, title=xAxisLabel)

        # Start adding the heatmaps
        for j in range(nRows):
            if perGroup:
                mat = hm.matrix.get_matrix(i, j)
                label = mat['sample']
                start = hm.matrix.group_boundaries[i]
                end = hm.matrix.group_boundaries[i + 1]
            else:
                mat = hm.matrix.get_matrix(j, i)
                label = mat['group']
                start = hm.matrix.group_boundaries[j]
                end = hm.matrix.group_boundaries[j + 1]
            regs = hm.matrix.regions[start:end]
            regs = [x[2] for x in regs]
            yanchor = 'y{}'.format(yAxisN)
            yDomain = [heatmapHeight - fractionalHeights[j + 1], heatmapHeight - fractionalHeights[j]]
            visible = False
            if i == 0:
                visible = True
            fig['layout']['yaxis{}'.format(yAxisN)] = dict(domain=yDomain, anchor=xanchor, visible=visible, title=label, tickmode='array', tickvals=[], ticktext=[])
            if np.min(mat['matrix']) < zMinLocal:
                zMinLocal = np.min(mat['matrix'])
            if np.max(mat['matrix']) < zMaxLocal:
                zMaxLocal = np.max(mat['matrix'])

            trace = go.Heatmap(z=np.flipud(mat['matrix']),
                               y=regs[::-1],
                               xaxis=xanchor,
                               yaxis=yanchor,
                               showlegend=False,
                               name=label,
                               showscale=False)

            dataHeatmap.append(trace)
            yAxisN += 1
        xAxisN += 1
    if showColorbar:
        dataHeatmap[-1].update(showscale=True)
        dataHeatmap[-1]['colorbar'].update(len=heatmapHeight, y=0, yanchor='bottom', ypad=0.0)

    # Adjust z bounds and colorscale
    for trace in dataHeatmap:
        zMinUse = zMinLocal
        zMaxUse = zMaxLocal
        if zMin[0] is not None:
            zMinUse = zMin[0]
        if zMax[0] is not None:
            zMaxUse = zMax[0]
        trace.update(zmin=zMinUse, zmax=zMaxUse, colorscale=convertCmap(cmap[0], vmin=zMinUse, vmax=zMaxUse))

    dataSummary.extend(dataHeatmap)
    fig['data'] = dataSummary
    fig['layout']['annotations'] = annos
    py.plot(fig, filename=outFilename, auto_open=False)


def plotMatrix(hm, outFileName,
               colorMapDict={'colorMap': ['binary'], 'missingDataColor': 'black', 'alpha': 1.0},
               plotTitle='',
               xAxisLabel='', yAxisLabel='', regionsLabel='',
               zMin=None, zMax=None,
               yMin=None, yMax=None,
               averageType='median',
               reference_point_label=None,
               startLabel='TSS', endLabel="TES",
               heatmapHeight=25,
               heatmapWidth=7.5,
               perGroup=False, whatToShow='plot, heatmap and colorbar',
               plot_type='lines',
               linesAtTickMarks=False,
               image_format=None,
               legend_location='upper-left',
               box_around_heatmaps=True,
               label_rotation=0.0,
               dpi=200,
               interpolation_method='auto'):

    hm.reference_point_label = hm.parameters['ref point']
    if reference_point_label is not None:
        hm.reference_point_label = [reference_point_label] * hm.matrix.get_num_samples()
    hm.startLabel = startLabel
    hm.endLabel = endLabel

    matrix_flatten = None
    if zMin is None:
        matrix_flatten = hm.matrix.flatten()
        # try to avoid outliers by using np.percentile
        zMin = np.percentile(matrix_flatten, 1.0)
        if np.isnan(zMin):
            zMin = [None]
        else:
            zMin = [zMin]  # convert to list to support multiple entries

    if zMax is None:
        if matrix_flatten is None:
            matrix_flatten = hm.matrix.flatten()
        # try to avoid outliers by using np.percentile
        zMax = np.percentile(matrix_flatten, 98.0)
        if np.isnan(zMax) or zMax <= zMin[0]:
            zMax = [None]
        else:
            zMax = [zMax]

    if yMin is None:
        yMin = [None]
    if yMax is None:
        yMax = [None]
    if not isinstance(yMin, list):
        yMin = [yMin]
    if not isinstance(yMax, list):
        yMax = [yMax]

    plt.rcParams['font.size'] = 8.0
    fontP = FontProperties()

    showSummaryPlot = False
    showColorbar = False

    if whatToShow == 'plot and heatmap':
        showSummaryPlot = True
    elif whatToShow == 'heatmap and colorbar':
        showColorbar = True
    elif whatToShow == 'plot, heatmap and colorbar':
        showSummaryPlot = True
        showColorbar = True

    # colormap for the heatmap
    if colorMapDict['colorMap']:
        cmap = []
        for color_map in colorMapDict['colorMap']:
            cmap.append(plt.get_cmap(color_map))
            cmap[-1].set_bad(colorMapDict['missingDataColor'])  # nans are printed using this color

    if colorMapDict['colorList'] and len(colorMapDict['colorList']) > 0:
        # make a cmap for each color list given
        cmap = []
        for color_list in colorMapDict['colorList']:
            cmap.append(matplotlib.colors.LinearSegmentedColormap.from_list(
                'my_cmap', color_list.replace(' ', '').split(","), N=colorMapDict['colorNumber']))
            cmap[-1].set_bad(colorMapDict['missingDataColor'])  # nans are printed using this color

    if len(cmap) > 1 or len(zMin) > 1 or len(zMax) > 1:
        # position color bar below heatmap when more than one
        # heatmap color is given
        colorbar_position = 'below'
    else:
        colorbar_position = 'side'

    grids = prepare_layout(hm.matrix, (heatmapWidth, heatmapHeight),
                           showSummaryPlot, showColorbar, perGroup, colorbar_position)

    # figsize: w,h tuple in inches
    figwidth = heatmapWidth / 2.54
    figheight = heatmapHeight / 2.54
    if showSummaryPlot:
        # the summary plot ocupies a height
        # equal to the fig width
        figheight += figwidth

    numsamples = hm.matrix.get_num_samples()
    if perGroup:
        num_cols = hm.matrix.get_num_groups()
    else:
        num_cols = numsamples
    total_figwidth = figwidth * num_cols
    if showColorbar:
        if colorbar_position == 'below':
            figheight += 1 / 2.54
        else:
            total_figwidth += 1 / 2.54

    fig = plt.figure(figsize=(total_figwidth, figheight))
    fig.suptitle(plotTitle, y=1 - (0.06 / figheight))

    # color map for the summary plot (profile) on top of the heatmap
    cmap_plot = plt.get_cmap('jet')
    numgroups = hm.matrix.get_num_groups()
    if perGroup:
        color_list = cmap_plot(np.arange(hm.matrix.get_num_samples()) / hm.matrix.get_num_samples())
    else:
        color_list = cmap_plot(np.arange(numgroups) / numgroups)
    alpha = colorMapDict['alpha']

    if image_format == 'plotly':
        return plotlyMatrix(hm,
                            outFileName,
                            yMin=yMin, yMax=yMax,
                            zMin=zMin, zMax=zMax,
                            showSummaryPlot=showSummaryPlot, showColorbar=showColorbar,
                            cmap=cmap, colorList=color_list, colorBarPosition=colorbar_position,
                            perGroup=perGroup,
                            averageType=averageType, plotTitle=plotTitle,
                            xAxisLabel=xAxisLabel, yAxisLabel=yAxisLabel,
                            label_rotation=label_rotation)

    # check if matrix is reference-point based using the upstream >0 value
    # and is sorted by region length. If this is
    # the case, prepare the data to plot a border at the regions end
    regions_length_in_bins = [None] * len(hm.parameters['upstream'])
    if hm.matrix.sort_using == 'region_length' and hm.matrix.sort_method != 'no':
        for idx in range(len(hm.parameters['upstream'])):
            if hm.parameters['ref point'][idx] is None:
                regions_length_in_bins[idx] = None
                continue

            _regions = hm.matrix.get_regions()
            foo = []
            for _group in _regions:
                _reg_len = []
                for ind_reg in _group:
                    if isinstance(ind_reg, dict):
                        _len = ind_reg['end'] - ind_reg['start']
                    else:
                        _len = sum([x[1] - x[0] for x in ind_reg[1]])
                    if hm.parameters['ref point'][idx] == 'TSS':
                        _reg_len.append((hm.parameters['upstream'][idx] + _len) / hm.parameters['bin size'][idx])
                    elif hm.parameters['ref point'][idx] == 'center':
                        _len *= 0.5
                        _reg_len.append((hm.parameters['upstream'][idx] + _len) / hm.parameters['bin size'][idx])
                    elif hm.parameters['ref point'][idx] == 'TES':
                        _reg_len.append((hm.parameters['upstream'][idx] - _len) / hm.parameters['bin size'][idx])
                foo.append(_reg_len)
            regions_length_in_bins[idx] = foo

    # plot the profiles on top of the heatmaps
    if showSummaryPlot:
        if perGroup:
            iterNum = numgroups
            iterNum2 = hm.matrix.get_num_samples()
        else:
            iterNum = hm.matrix.get_num_samples()
            iterNum2 = numgroups
        ax_list = addProfilePlot(hm, plt, fig, grids, iterNum, iterNum2, perGroup, averageType, plot_type, yAxisLabel, color_list, yMin, yMax, None, None, colorbar_position, label_rotation)
        if len(yMin) > 1 or len(yMax) > 1:
            # replot with a tight layout
            import matplotlib.tight_layout as tl
            specList = tl.get_subplotspec_list(fig.axes, grid_spec=grids)
            renderer = tl.get_renderer(fig)
            kwargs = tl.get_tight_layout_figure(fig, fig.axes, specList, renderer, pad=1.08)

            for ax in ax_list:
                fig.delaxes(ax)

            ax_list = addProfilePlot(hm, plt, fig, grids, iterNum, iterNum2, perGroup, averageType, plot_type, yAxisLabel, color_list, yMin, yMax, kwargs['wspace'], kwargs['hspace'], colorbar_position, label_rotation)

        if legend_location != 'none':
            ax_list[-1].legend(loc=legend_location.replace('-', ' '), ncol=1, prop=fontP,
                               frameon=False, markerscale=0.5)

    first_group = 0  # helper variable to place the title per sample/group
    for sample in range(hm.matrix.get_num_samples()):
        sample_idx = sample
        for group in range(numgroups):
            group_idx = group
            # add the respective profile to the
            # summary plot
            sub_matrix = hm.matrix.get_matrix(group, sample)
            if showSummaryPlot:
                if perGroup:
                    sample_idx = sample + 2  # plot + spacer
                else:
                    group += 2  # plot + spacer
                first_group = 1

            if perGroup:
                ax = fig.add_subplot(grids[sample_idx, group])
                # the remainder (%) is used to iterate
                # over the available color maps (cmap).
                # if the user only provided, lets say two
                # and there are 10 groups, colormaps they are reused every
                # two groups.
                cmap_idx = group_idx % len(cmap)
                zmin_idx = group_idx % len(zMin)
                zmax_idx = group_idx % len(zMax)
            else:
                ax = fig.add_subplot(grids[group, sample])
                # see above for the use of '%'
                cmap_idx = sample % len(cmap)
                zmin_idx = sample % len(zMin)
                zmax_idx = sample % len(zMax)

            if group == first_group and not showSummaryPlot and not perGroup:
                title = hm.matrix.sample_labels[sample]
                ax.set_title(title)

            if box_around_heatmaps is False:
                # Turn off the boxes around the individual heatmaps
                ax.spines['top'].set_visible(False)
                ax.spines['right'].set_visible(False)
                ax.spines['bottom'].set_visible(False)
                ax.spines['left'].set_visible(False)
            rows, cols = sub_matrix['matrix'].shape
            # if the number of rows is too large, then the 'nearest' method simply
            # drops rows. A better solution is to relate the threshold to the DPI of the image
            if interpolation_method == 'auto':
                if rows >= 1000:
                    interpolation_method = 'bilinear'
                else:
                    interpolation_method = 'nearest'

            # if np.clip is not used, then values of the matrix that exceed the zmax limit are
            # highlighted. Usually, a significant amount of pixels are equal or above the zmax and
            # the default behaviour produces images full of large highlighted dots.
            # If interpolation='nearest' is used, this has no effect
            sub_matrix['matrix'] = np.clip(sub_matrix['matrix'], zMin[zmin_idx], zMax[zmax_idx])
            img = ax.imshow(sub_matrix['matrix'],
                            aspect='auto',
                            interpolation=interpolation_method,
                            origin='upper',
                            vmin=zMin[zmin_idx],
                            vmax=zMax[zmax_idx],
                            cmap=cmap[cmap_idx],
                            alpha=alpha,
                            extent=[0, cols, rows, 0])
            img.set_rasterized(True)
            # plot border at the end of the regions
            # if ordered by length
            if regions_length_in_bins[sample] is not None:
                x_lim = ax.get_xlim()
                y_lim = ax.get_ylim()

                ax.plot(regions_length_in_bins[sample][group_idx],
                        np.arange(len(regions_length_in_bins[sample][group_idx])),
                        '--', color='black', linewidth=0.5, dashes=(3, 2))
                ax.set_xlim(x_lim)
                ax.set_ylim(y_lim)

            if perGroup:
                ax.axes.set_xlabel(sub_matrix['group'])
                if sample < hm.matrix.get_num_samples() - 1:
                    ax.axes.get_xaxis().set_visible(False)
            else:
                ax.axes.get_xaxis().set_visible(False)
                ax.axes.set_xlabel(xAxisLabel)
            ax.axes.set_yticks([])
            if perGroup and group == 0:
                ax.axes.set_ylabel(sub_matrix['sample'])
            elif not perGroup and sample == 0:
                ax.axes.set_ylabel(sub_matrix['group'])

            # Plot vertical lines at tick marks if desired
            if linesAtTickMarks:
                xticks_heat, xtickslabel_heat = hm.getTicks(sample)
                xticks_heat = [x + 0.5 for x in xticks_heat]  # There's an offset of 0.5 compared to the profile plot
                if np.ceil(max(xticks_heat)) != float(sub_matrix['matrix'].shape[1]):
                    tickscale = float(sub_matrix['matrix'].shape[1]) / max(xticks_heat)
                    xticks_heat_use = [x * tickscale for x in xticks_heat]
                else:
                    xticks_heat_use = xticks_heat
                for x in xticks_heat_use:
                    ax.axvline(x=x, color='black', linewidth=0.5, dashes=(3, 2))

            # add labels to last block in a column
            if (perGroup and sample == numsamples - 1) or \
               (not perGroup and group_idx == numgroups - 1):

                # add xticks to the bottom heatmap (last group)
                ax.axes.get_xaxis().set_visible(True)
                xticks_heat, xtickslabel_heat = hm.getTicks(sample)
                xticks_heat = [x + 0.5 for x in xticks_heat]  # There's an offset of 0.5 compared to the profile plot
                if np.ceil(max(xticks_heat)) != float(sub_matrix['matrix'].shape[1]):
                    tickscale = float(sub_matrix['matrix'].shape[1]) / max(xticks_heat)
                    xticks_heat_use = [x * tickscale for x in xticks_heat]
                    ax.axes.set_xticks(xticks_heat_use)
                else:
                    ax.axes.set_xticks(xticks_heat)
                ax.axes.set_xticklabels(xtickslabel_heat, size=8)

                # align the first and last label
                # such that they don't fall off
                # the heatmap sides
                ticks = ax.xaxis.get_major_ticks()
                ticks[0].label1.set_horizontalalignment('left')
                ticks[-1].label1.set_horizontalalignment('right')

                ax.get_xaxis().set_tick_params(
                    which='both',
                    top=False,
                    direction='out')

                if showColorbar and colorbar_position == 'below':
                    # draw a colormap per each heatmap below the last block
                    if perGroup:
                        col = group_idx
                    else:
                        col = sample
                    ax = fig.add_subplot(grids[-1, col])
                    tick_locator = ticker.MaxNLocator(nbins=3)
                    cbar = fig.colorbar(img, cax=ax, alpha=alpha, orientation='horizontal', ticks=tick_locator)
                    labels = cbar.ax.get_xticklabels()
                    ticks = cbar.ax.get_xticks()
                    if ticks[0] == 0:
                        # if the label is at the start of the colobar
                        # move it a bit inside to avoid overlapping
                        # with other labels
                        labels[0].set_horizontalalignment('left')
                    if ticks[-1] == 1:
                        # if the label is at the end of the colobar
                        # move it a bit inside to avoid overlapping
                        # with other labels
                        labels[-1].set_horizontalalignment('right')
                    # cbar.ax.set_xticklabels(labels, rotation=90)

    if showColorbar and colorbar_position != 'below':
        if showSummaryPlot:
            # we don't want to colorbar to extend
            # over the profiles and spacer top rows
            grid_start = 2
        else:
            grid_start = 0

        ax = fig.add_subplot(grids[grid_start:, -1])
        fig.colorbar(img, cax=ax, alpha=alpha)

    if box_around_heatmaps:
        plt.subplots_adjust(wspace=0.10, hspace=0.025, top=0.85, bottom=0, left=0.04, right=0.96)
    else:
        #  When no box is plotted the space between heatmaps is reduced
        plt.subplots_adjust(wspace=0.05, hspace=0.01, top=0.85, bottom=0, left=0.04, right=0.96)

    plt.savefig(outFileName, bbox_inches='tight', pdd_inches=0, dpi=dpi, format=image_format)
    plt.close()


def mergeSmallGroups(matrixDict):
    group_lengths = [len(x) for x in matrixDict.values()]
    min_group_length = sum(group_lengths) * 0.01

    to_merge = []
    i = 0
    _mergedHeatMapDict = OrderedDict()

    for label, ma in matrixDict.items():
        # merge small groups together
        # otherwise visualization is impaired
        if group_lengths[i] > min_group_length:
            if len(to_merge):
                to_merge.append(label)
                new_label = " ".join(to_merge)
                new_ma = np.concatenate([matrixDict[item]
                                        for item in to_merge], axis=0)
            else:
                new_label = label
                new_ma = matrixDict[label]

            _mergedHeatMapDict[new_label] = new_ma
            to_merge = []
        else:
            to_merge.append(label)
        i += 1
    if len(to_merge) > 1:
        new_label = " ".join(to_merge)
        new_ma = np.array()
        for item in to_merge:
            new_ma = np.concatenate([new_ma, matrixDict[item]])
        _mergedHeatMapDict[new_label] = new_ma

    return _mergedHeatMapDict


def main(args=None):
    args = process_args(args)
    hm = heatmapper.heatmapper()
    matrix_file = args.matrixFile.name
    args.matrixFile.close()
    hm.read_matrix_file(matrix_file)

    if hm.parameters['min threshold'] is not None or hm.parameters['max threshold'] is not None:
        filterHeatmapValues(hm, hm.parameters['min threshold'], hm.parameters['max threshold'])

    if args.sortRegions == 'keep':
        args.sortRegions = 'no'  # These are the same thing
    if args.kmeans is not None:
        hm.matrix.hmcluster(args.kmeans, method='kmeans', clustering_samples=args.clusterUsingSamples)
    elif args.hclust is not None:
        print("Performing hierarchical clustering."
              "Please note that it might be very slow for large datasets.\n")
        hm.matrix.hmcluster(args.hclust, method='hierarchical', clustering_samples=args.clusterUsingSamples)

    group_len_ratio = np.diff(hm.matrix.group_boundaries) / len(hm.matrix.regions)
    if np.any(group_len_ratio < 5.0 / 1000):
        problem = np.flatnonzero(group_len_ratio < 5.0 / 1000)
        sys.stderr.write("WARNING: Group '{}' is too small for plotting, you might want to remove it. "
                         "There will likely be an error message from matplotlib regarding this "
                         "below.\n".format(hm.matrix.group_labels[problem[0]]))

    if args.regionsLabel:
        hm.matrix.set_group_labels(args.regionsLabel)

    if args.samplesLabel and len(args.samplesLabel):
        hm.matrix.set_sample_labels(args.samplesLabel)

    if args.sortRegions != 'no':
        sortUsingSamples = []
        if args.sortUsingSamples is not None:
            for i in args.sortUsingSamples:
                if (i > 0 and i <= hm.matrix.get_num_samples()):
                    sortUsingSamples.append(i - 1)
                else:
                    exit("The value {0} for --sortSamples is not valid. Only values from 1 to {1} are allowed.".format(args.sortUsingSamples, hm.matrix.get_num_samples()))
            print('Samples used for ordering within each group: ', sortUsingSamples)

        hm.matrix.sort_groups(sort_using=args.sortUsing,
                              sort_method=args.sortRegions,
                              sample_list=sortUsingSamples)

    if args.silhouette:
        if args.kmeans is not None:
            hm.matrix.computeSilhouette(args.kmeans)
        elif args.hclust is not None:
            hm.matrix.computeSilhouette(args.args.hclust)

    if args.outFileNameMatrix:
        hm.save_matrix_values(args.outFileNameMatrix)

    if args.outFileSortedRegions:
        hm.save_BED(args.outFileSortedRegions)

    colormap_dict = {'colorMap': args.colorMap,
                     'colorList': args.colorList,
                     'colorNumber': args.colorNumber,
                     'missingDataColor': args.missingDataColor,
                     'alpha': args.alpha}

    plotMatrix(hm,
               args.outFileName,
               colormap_dict, args.plotTitle,
               args.xAxisLabel, args.yAxisLabel, args.regionsLabel,
               args.zMin, args.zMax,
               args.yMin, args.yMax,
               args.averageTypeSummaryPlot,
               args.refPointLabel,
               args.startLabel,
               args.endLabel,
               args.heatmapHeight,
               args.heatmapWidth,
               args.perGroup,
               args.whatToShow,
               linesAtTickMarks=args.linesAtTickMarks,
               plot_type=args.plotType,
               image_format=args.plotFileFormat,
               legend_location=args.legendLocation,
               box_around_heatmaps=args.boxAroundHeatmaps,
               label_rotation=args.label_rotation,
               dpi=args.dpi,
               interpolation_method=args.interpolationMethod)
