"""
@package wxplot.scatter

@brief Scatter plotting using PyPlot

Classes:
 - scatter::ScatterFrame
 - scatter::ScatterToolbar

(C) 2011 by the GRASS Development Team

This program is free software under the GNU General Public License
(>=v2). Read the file COPYING that comes with GRASS for details.

@author Michael Barton, Arizona State University
"""

import sys

import wx

import grass.script as grass
import wx.lib.plot as plot
from wxplot.base import BasePlotFrame, PlotIcons
from gui_core.toolbars import BaseToolbar, BaseIcons
from gui_core.wrap import StockCursor
from wxplot.dialogs import ScatterRasterDialog, PlotStatsFrame
from core.gcmd import RunCommand, GException, GError, GMessage


class ScatterFrame(BasePlotFrame):
    """Mainframe for displaying bivariate scatter plot of two raster maps. Uses wx.lib.plot.
    """

    def __init__(self, parent, giface, id=wx.ID_ANY, style=wx.DEFAULT_FRAME_STYLE,
                 size=wx.Size(700, 400),
                 rasterList=[], **kwargs):
        BasePlotFrame.__init__(self, parent, giface=giface, size=size, **kwargs)

        self.toolbar = ScatterToolbar(parent=self)
        # workaround for http://trac.wxwidgets.org/ticket/13888
        if sys.platform != 'darwin':
            self.SetToolBar(self.toolbar)
        self.SetTitle(_("GRASS Bivariate Scatterplot Tool"))

        #
        # Init variables
        #
        self.rasterList = rasterList
        self.plottype = 'scatter'
        self.ptitle = _('Bivariate Scatterplot')     # title of window
        self.xlabel = _("Raster cell values")           # default X-axis label
        self.ylabel = _("Raster cell values")           # default Y-axis label
        self.maptype = 'raster'                         # default type of scatterplot
        self.scattertype = 'normal'
        self.bins = 255
        self.colorList = [
            "blue",
            "red",
            "black",
            "green",
            "yellow",
            "magenta",
            "cyan",
            "aqua",
            "grey",
            "orange",
            "brown",
            "purple",
            "violet",
            "indigo"]

        self._initOpts()

        if len(
                self.rasterList) > 1:  # set raster name(s) from layer manager if a map is selected
            self.InitRasterOpts(self.rasterList, 'scatter')
        else:
            self.raster = {}

    def _initOpts(self):
        """Initialize plot options
        """
        self.InitPlotOpts('scatter')

    def OnCreateScatter(self, event):
        """Main routine for creating a scatterplot. Uses r.stats to
        create a list of cell value pairs. This is passed to
        plot to create a scatterplot.
        """
        self.SetCursor(StockCursor(wx.CURSOR_ARROW))
        self.SetGraphStyle()
        wx.BeginBusyCursor()
        wx.SafeYield()
        self.SetupScatterplot()
        p = self.CreatePlotList()
        if p:
            self.DrawPlot(p)
            wx.EndBusyCursor()
        else:
            wx.EndBusyCursor()
            GMessage(_("Nothing to plot."), parent=self)

    def OnSelectRaster(self, event):
        """Select raster map(s) to profile
        """
        dlg = ScatterRasterDialog(parent=self)
        dlg.CenterOnParent()
        if dlg.ShowModal() == wx.ID_OK:
            self.rasterList = dlg.GetRasterPairs()
            if not self.rasterList:
                GMessage(
                    _("At least 2 raster maps must be specified"),
                    parent=dlg)
                return

            # scatterplot or bubbleplot
            # bins for r.stats with float and dcell maps
            self.scattertype, self.bins = dlg.GetSettings()
            self.raster = self.InitRasterPairs(
                self.rasterList, 'scatter')  # dictionary of raster pairs

            # plot histogram
            if self.rasterList:
                self.OnCreateScatter(event=None)

        dlg.Destroy()

    def SetupScatterplot(self):
        """Build data list for ploting each raster
        """

        #
        # initialize title string
        #
        self.ptitle = _('Bivariate Scatterplot of ')

        #
        # create a datalist for plotting for each raster pair
        #
        if len(self.rasterList) == 0:
            return  # at least 1 pair of maps needed to plot

        for rpair in self.rasterList:
            self.raster[rpair]['datalist'] = self.CreateDatalist(rpair)

            # update title
            self.ptitle += '%s vs %s, ' % (
                rpair[0].split('@')[0],
                rpair[1].split('@')[0])

        self.ptitle = self.ptitle.strip(', ')

        #
        # set xlabel & ylabel based on raster maps of first pair to be plotted
        #
        self.xlabel = _('Raster <%s> cell values') % rpair[0].split('@')[0]
        self.ylabel = _('Raster <%s> cell values') % rpair[1].split('@')[0]

        units = self.raster[self.rasterList[0]][0]['units']
        if units != '':
            self.xlabel += _(': %s') % units

        units = self.raster[self.rasterList[0]][1]['units']
        if units != '':
            self.ylabel += _(': %s') % units

    def CreateDatalist(self, rpair):
        """Build a list of cell value, frequency pairs for histogram
            frequency can be in cell counts, percents, or area
        """
        datalist = []

        if self.scattertype == 'bubble':
            freqflag = 'cn'
        else:
            freqflag = 'n'

        try:
            ret = RunCommand("r.stats",
                             parent=self,
                             input='%s,%s' % rpair,
                             flags=freqflag,
                             nsteps=self.bins,
                             sep=',',
                             quiet=True,
                             read=True)

            if not ret:
                return datalist

            for line in ret.splitlines():
                rast1, rast2 = line.strip().split(',')
                rast1 = rast1.strip()
                if '-' in rast1:
                    if rast1[0] == '-':
                        rast1 = '-' + rast1.split('-')[1]
                    else:
                        rast1 = rast1.split('-')[0]

                rast2 = rast2.strip()
                if '-' in rast2:
                    if rast2[0] == '-':
                        rast2 = '-' + rast2.split('-')[1]
                    else:
                        rast2 = rast2.split('-')[0]

                rast1 = rast1.encode('ascii', 'ignore')
                rast2 = rast2.encode('ascii', 'ignore')

                datalist.append((rast1, rast2))

            return datalist
        except GException as e:
            GError(parent=self,
                   message=e.value)
            return None

    def CreatePlotList(self):
        """Make list of elements to plot
        """
        # graph the cell value, frequency pairs for the histogram
        self.plotlist = []

        for rpair in self.rasterList:
            if 'datalist' not in self.raster[rpair] or \
                    self.raster[rpair]['datalist'] is None:
                continue

            if len(self.raster[rpair]['datalist']) > 0:
                col = wx.Colour(self.raster[rpair]['pcolor'][0],
                                self.raster[rpair]['pcolor'][1],
                                self.raster[rpair]['pcolor'][2],
                                255)
                scatterpoints = plot.PolyMarker(
                    self.raster[rpair]['datalist'],
                    legend=' ' + self.raster[rpair]['plegend'],
                    colour=col, size=self.raster[rpair]['psize'],
                    fillstyle=self.ptfilldict[self.raster[rpair]['pfill']],
                    marker=self.raster[rpair]['ptype'])

                self.plotlist.append(scatterpoints)

        return self.plotlist

    def Update(self):
        """Update histogram after changing options
        """
        self.SetGraphStyle()
        p = self.CreatePlotList()
        if p:
            self.DrawPlot(p)
        else:
            GMessage(_("Nothing to plot."), parent=self)

    def OnRegression(self, event):
        """Displays regression information in messagebox
        """
        message = []
        title = _('Regression Statistics for Scatterplot(s)')

        for rpair in self.rasterList:
            if isinstance(rpair, tuple) == False:
                continue
            rast1, rast2 = rpair
            rast1 = rast1.split('@')[0]
            rast2 = rast2.split('@')[0]
            ret = grass.parse_command(
                'r.regression.line', mapx=rast1, mapy=rast2, flags='g',
                quiet=True, parse=(grass.parse_key_val, {'sep': '='}))
            eqtitle = _('Regression equation for raster map <%(rast1)s> vs. <%(rast2)s>:\n\n') % {
                'rast1': rast1, 'rast2': rast2}
            eq = '   %s = %s + %s(%s)\n\n' % (rast2, ret['a'], ret['b'], rast1)
            num = 'N = %s\n' % ret['N']
            rval = 'R = %s\n' % ret['R']
            rsq = 'R-squared = %f\n' % pow(float(ret['R']), 2)
            ftest = 'F = %s\n' % ret['F']
            str = eqtitle + eq + num + rval + rsq + ftest
            message.append(str)

        stats = PlotStatsFrame(self, id=wx.ID_ANY, message=message,
                               title=title)

        if stats.Show() == wx.ID_CLOSE:
            stats.Destroy()


class ScatterToolbar(BaseToolbar):
    """Toolbar for bivariate scatterplots of raster map pairs
    """

    def __init__(self, parent):
        BaseToolbar.__init__(self, parent)

        # workaround for http://trac.wxwidgets.org/ticket/13888
        if sys.platform == 'darwin':
            parent.SetToolBar(self)

        self.InitToolbar(self._toolbarData())

        # realize the toolbar
        self.Realize()

    def _toolbarData(self):
        """Toolbar data"""
        return self._getToolbarData((('addraster', BaseIcons["addRast"],
                                      self.parent.OnSelectRaster),
                                     (None, ),
                                     ('draw', PlotIcons["draw"],
                                      self.parent.OnCreateScatter),
                                     ('erase', BaseIcons["erase"],
                                      self.parent.OnErase),
                                     ('drag', BaseIcons['pan'],
                                      self.parent.OnDrag),
                                     ('zoom', BaseIcons['zoomIn'],
                                      self.parent.OnZoom),
                                     ('unzoom', BaseIcons['zoomBack'],
                                      self.parent.OnRedraw),
                                     (None, ),
                                     ('statistics', PlotIcons['statistics'],
                                      self.parent.OnRegression),
                                     ('image', BaseIcons["saveFile"],
                                      self.parent.SaveToFile),
                                     ('print', BaseIcons["print"],
                                      self.parent.PrintMenu),
                                     (None, ),
                                     ('settings', PlotIcons["options"],
                                      self.parent.PlotOptionsMenu),
                                     ('quit', PlotIcons["quit"],
                                      self.parent.OnQuit),
                                     ))
