"""
@package wxplot.profile

@brief Profiling using PyPlot

Classes:
 - profile::ProfileFrame
 - profile::ProfileToolbar

(C) 2011-2014 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 os
import sys
import six
import math
import numpy

import wx

import gui_core.wxlibplot as plot
import grass.script as grass
from wxplot.base import BasePlotFrame, PlotIcons
from gui_core.toolbars import BaseToolbar, BaseIcons
from gui_core.wrap import StockCursor
from wxplot.dialogs import ProfileRasterDialog, PlotStatsFrame
from core.gcmd import RunCommand, GWarning, GError, GMessage


class ProfileFrame(BasePlotFrame):
    """Mainframe for displaying profile of one or more raster maps. Uses wx.lib.plot.
    """

    def __init__(self, parent, controller, units, size=wx.Size(700, 400),
                 rasterList=None, **kwargs):
        BasePlotFrame.__init__(self, parent=parent, size=size, **kwargs)

        self.controller = controller
        self.controller.transectChanged.connect(self.SetTransect)
        self.transect = []
        self.toolbar = ProfileToolbar(parent=self)
        # workaround for http://trac.wxwidgets.org/ticket/13888
        if sys.platform != 'darwin':
            self.SetToolBar(self.toolbar)
        self.SetTitle(_("GRASS Profile Analysis Tool"))
        # in case of degrees, we want to use meters
        self._units = units if 'degree' not in units else 'meters'

        #
        # Init variables
        #
        if rasterList is None:
            self.rasterList = []
        else:
            self.rasterList = rasterList
        self.plottype = 'profile'
        self.coordstr = ''              # string of coordinates for r.profile
        self.seglist = []               # segment endpoint list
        self.ppoints = ''               # segment endpoints data
        self.transect_length = 0.0      # total transect length
        self.ptitle = _('Profile of')   # title of window
        self.colorList = [
            "blue",
            "red",
            "green",
            "yellow",
            "magenta",
            "cyan",
            "aqua",
            "black",
            "grey",
            "orange",
            "brown",
            "purple",
            "violet",
            "indigo"]

        self._initOpts()

        if len(
                self.rasterList) > 0:  # set raster name(s) from layer manager if a map is selected
            self.raster = self.InitRasterOpts(self.rasterList, self.plottype)
        else:
            self.raster = {}

        # determine units (axis labels)
        # maybe, we should not accept these invalid units
        # but ok, trying to handle it here
        if self._units is not None and self._units != '':
            self.xlabel = _('Distance (%s)') % self._units
        else:
            self.xlabel = _("Distance along transect")
        self.ylabel = _("Cell values")

        # Bind events
        self.Bind(wx.EVT_CLOSE, self.OnCloseWindow)

        self.SetGraphStyle()

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

    def SetTransect(self, coords):
        self.transect = coords
        if coords:
            self.OnCreateProfile(None)
        else:
            self.OnErase(None)

    def OnDrawTransect(self, event):
        """Draws transect to profile in map display
        """
        if self.controller.IsActive():
            self.controller.Stop()
        self.controller.Start()

        self.parent.SetFocus()
        self.parent.Raise()

    def OnSelectRaster(self, event):
        """Select raster map(s) to profile
        """
        dlg = ProfileRasterDialog(parent=self)
        dlg.CenterOnParent()
        if dlg.ShowModal() == wx.ID_OK:
            self.rasterList = dlg.rasterList
            self.raster = self.InitRasterOpts(self.rasterList, self.plottype)

            # plot profile
            if len(self.transect) > 0 and len(self.rasterList) > 0:
                self.OnCreateProfile(event=None)

        dlg.Destroy()

    def SetupProfile(self):
        """Create coordinate string for profiling. Create segment
           list for transect segment markers.
        """
        # create list of coordinate points for r.profile
        dist = 0
        cumdist = 0
        self.coordstr = ''
        lasteast = lastnorth = None

        region = grass.region()
        insideRegion = True
        if len(self.transect) > 0:
            for point in self.transect:
                if not (region['w'] <= point[0] <= region['e']
                        and region['s'] <= point[1] <= region['n']):
                    insideRegion = False
                # build string of coordinate points for r.profile
                if self.coordstr == '':
                    self.coordstr = '%f,%f' % (point[0], point[1])
                else:
                    self.coordstr = '%s,%f,%f' % (
                        self.coordstr, point[0], point[1])

        if not insideRegion:
            GWarning(
                message=_(
                    "Not all points of profile lie inside computational region."),
                parent=self)

        if len(self.rasterList) == 0:
            return

        # title of window
        self.ptitle = _('Profile of')

        # create list of coordinates for transect segment markers
        if len(self.transect) > 0:
            self.seglist = []
            for point in self.transect:
                # get value of raster cell at coordinate point
                ret = RunCommand('r.what',
                                 parent=self,
                                 read=True,
                                 map=self.rasterList[0],
                                 coordinates='%f,%f' % (point[0], point[1]))

                val = ret.splitlines()[0].split('|')[3]
                if val is None or val == '*':
                    continue
                val = float(val)

                # calculate distance between coordinate points
                if lasteast and lastnorth:
                    dist = math.sqrt(
                        math.pow((lasteast - point[0]),
                                 2) + math.pow((lastnorth - point[1]),
                                               2))
                cumdist += dist

                # store total transect length
                self.transect_length = cumdist

                # build a list of distance,value pairs for each segment of
                # transect
                self.seglist.append((cumdist, val))
                lasteast = point[0]
                lastnorth = point[1]

            # delete extra first segment point
            try:
                self.seglist.pop(0)
            except:
                pass

        #
        # create datalist of dist/value pairs and y labels for each raster map
        #
        self.ylabel = ''
        i = 0

        for r in six.iterkeys(self.raster):
            self.raster[r]['datalist'] = []
            datalist = self.CreateDatalist(r, self.coordstr)
            if len(datalist) > 0:
                self.raster[r]['datalist'] = datalist

                # update ylabel to match units if they exist
                if self.raster[r]['units'] != '':
                    self.ylabel += '%s (%d),' % (self.raster[r]['units'], i)
                i += 1

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

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

        if self.ylabel == '':
            self.ylabel = _('Raster values')
        else:
            self.ylabel = self.ylabel.rstrip(',')

    def CreateDatalist(self, raster, coords):
        """Build a list of distance, value pairs for points along transect using r.profile
        """
        datalist = []

        # keep total number of transect points to 500 or less to avoid
        # freezing with large, high resolution maps
        region = grass.region()
        curr_res = min(float(region['nsres']), float(region['ewres']))
        transect_rec = 0
        if self.transect_length / curr_res > 500:
            transect_res = self.transect_length / 500
        else:
            transect_res = curr_res

        ret = RunCommand("r.profile",
                         parent=self,
                         input=raster,
                         coordinates=coords,
                         resolution=transect_res,
                         null="nan",
                         quiet=True,
                         read=True)

        if not ret:
            return []

        for line in ret.splitlines():
            dist, elev = line.strip().split(' ')
            if dist is None or dist == '' or dist == 'nan' or \
                    elev is None or elev == '' or elev == 'nan':
                continue
            dist = float(dist)
            elev = float(elev)
            datalist.append((dist, elev))

        return datalist

    def OnCreateProfile(self, event):
        """Main routine for creating a profile. Uses r.profile to
        create a list of distance,cell value pairs. This is passed to
        plot to create a line graph of the profile. If the profile
        transect is in multiple segments, these are drawn as
        points. Profile transect is drawn, using methods in mapdisp.py
        """

        if len(self.transect) == 0 or len(self.rasterList) == 0:
            dlg = wx.MessageDialog(
                parent=self,
                message=_('You must draw a transect to profile in the map display window.'),
                caption=_('Nothing to profile'),
                style=wx.OK | wx.ICON_INFORMATION | wx.CENTRE)
            dlg.ShowModal()
            dlg.Destroy()
            return

        self.SetCursor(StockCursor(wx.CURSOR_ARROW))

        self.SetupProfile()
        p = self.CreatePlotList()
        self.DrawPlot(p)

    def CreatePlotList(self):
        """Create a plot data list from transect datalist and
            transect segment endpoint coordinates.
        """
        # graph the distance, value pairs for the transect
        self.plotlist = []

        # Add segment marker points to plot data list
        if len(self.seglist) > 0:
            self.ppoints = plot.PolyMarker(
                self.seglist,
                legend=' ' + self.properties['marker']['legend'],
                colour=wx.Colour(
                    self.properties['marker']['color'][0],
                    self.properties['marker']['color'][1],
                    self.properties['marker']['color'][2],
                    255),
                size=self.properties['marker']['size'],
                fillstyle=self.ptfilldict[
                    self.properties['marker']['fill']],
                marker=self.properties['marker']['type'])
            self.plotlist.append(self.ppoints)

        # Add profile distance/elevation pairs to plot data list for each
        # raster profiled
        for r in self.rasterList:
            col = wx.Colour(self.raster[r]['pcolor'][0],
                            self.raster[r]['pcolor'][1],
                            self.raster[r]['pcolor'][2],
                            255)
            self.raster[r]['pline'] = plot.PolyLine(
                self.raster[r]['datalist'],
                colour=col, width=self.raster[r]['pwidth'],
                style=self.linestyledict[self.raster[r]['pstyle']],
                legend=self.raster[r]['plegend'])

            self.plotlist.append(self.raster[r]['pline'])

        if len(self.plotlist) > 0:
            return self.plotlist
        else:
            return None

    def Update(self):
        """Update profile after changing options
        """
        self.SetGraphStyle()
        p = self.CreatePlotList()
        self.DrawPlot(p)

    def SaveProfileToFile(self, event):
        """Save r.profile data to a csv file
        """
        dlg = wx.FileDialog(
            parent=self,
            message=_(
                "Choose prefix for file(s) where to save profile values..."),
            defaultDir=os.getcwd(),
            wildcard=_("Comma separated value (*.csv)|*.csv"),
            style=wx.FD_SAVE)
        pfile = []
        if dlg.ShowModal() == wx.ID_OK:
            path = dlg.GetPath()
            for r in self.rasterList:
                pfile.append(path + '_' + str(r.replace('@', '_')) + '.csv')
                if os.path.exists(pfile[-1]):
                    dlgOv = wx.MessageDialog(
                        self,
                        message=_(
                            "File <%s> already exists. "
                            "Do you want to overwrite this file?") % pfile
                        [-1],
                        caption=_("Overwrite file?"),
                        style=wx.YES_NO | wx.YES_DEFAULT | wx.ICON_QUESTION)
                    if dlgOv.ShowModal() != wx.ID_YES:
                        pfile.pop()
                        dlgOv.Destroy()
                        continue

                try:
                    fd = open(pfile[-1], "w")
                except IOError as e:
                    GError(parent=self,
                           message=_("Unable to open file <%s> for writing.\n"
                                     "Reason: %s") % (pfile[-1], e))
                    dlg.Destroy()
                    return

                for datapair in self.raster[r]['datalist']:
                    fd.write(
                        '%.6f,%.6f\n' %
                        (float(
                            datapair[0]), float(
                            datapair[1])))

                fd.close()

        dlg.Destroy()
        if pfile:
            message = _("%d files created:\n%s") % (
                len(pfile), '\n'.join(pfile))
        else:
            message = _("No files generated.")

        GMessage(parent=self, message=message)

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

        for r in six.iterkeys(self.raster):
            try:
                rast = r.split('@')[0]
                statstr = 'Profile of %s\n\n' % rast

                iterable = (i[1] for i in self.raster[r]['datalist'])
                a = numpy.fromiter(iterable, numpy.float)

                statstr += 'n: %f\n' % a.size
                statstr += 'minimum: %f\n' % numpy.amin(a)
                statstr += 'maximum: %f\n' % numpy.amax(a)
                statstr += 'range: %f\n' % numpy.ptp(a)
                statstr += 'mean: %f\n' % numpy.mean(a)
                statstr += 'standard deviation: %f\n' % numpy.std(a)
                statstr += 'variance: %f\n' % numpy.var(a)
                cv = numpy.std(a) / numpy.mean(a)
                statstr += 'coefficient of variation: %f\n' % cv
                statstr += 'sum: %f\n' % numpy.sum(a)
                statstr += 'median: %f\n' % numpy.median(a)
                statstr += 'distance along transect: %f\n\n' % self.transect_length
                message.append(statstr)
            except:
                pass

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

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

    def OnCloseWindow(self, event):
        if self.controller.IsActive():
            self.controller.Stop()
        self.Destroy()


class ProfileToolbar(BaseToolbar):
    """Toolbar for profiling raster map
    """

    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),
                                     ('transect', PlotIcons["transect"],
                                      self.parent.OnDrawTransect),
                                     (None, ),
                                     ('draw', PlotIcons["draw"],
                                      self.parent.OnCreateProfile),
                                     ('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.OnStats),
                                     ('datasave', PlotIcons["save"],
                                      self.parent.SaveProfileToFile),
                                     ('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),
                                     ))
