#!/usr/bin/env python
import svg.charts.plot
import re
import pkg_resources
pkg_resources.require("python-dateutil>=1.1")
from dateutil.parser import parse
from dateutil.relativedelta import relativedelta
from time import mktime
import datetime
fromtimestamp = datetime.datetime.fromtimestamp
from .util import float_range

class Plot(svg.charts.plot.Plot):
    """=== For creating SVG plots of scalar temporal data
        
        = Synopsis
        
          import SVG.TimeSeries
        
          # Data sets are x,y pairs
          data1 = ["6/17/72", 11,    "1/11/72", 7,    "4/13/04 17:31", 11, 
                  "9/11/01", 9,    "9/1/85", 2,    "9/1/88", 1,    "1/15/95", 13]
          data2 = ["8/1/73", 18,    "3/1/77", 15,    "10/1/98", 4, 
                  "5/1/02", 14,    "3/1/95", 6,    "8/1/91", 12,    "12/1/87", 6, 
                  "5/1/84", 17,    "10/1/80", 12]
        
          graph = SVG::Graph::TimeSeries.new({
            :width => 640,
            :height => 480,
            :graph_title => title,
            :show_graph_title => true,
            :no_css => true,
            :key => true,
            :scale_x_integers => true,
            :scale_y_integers => true,
            :min_x_value => 0,
            :min_y_value => 0,
            :show_data_labels => true,
            :show_x_guidelines => true,
            :show_x_title => true,
            :x_title => "Time",
            :show_y_title => true,
            :y_title => "Ice Cream Cones",
            :y_title_text_direction => :bt,
            :stagger_x_labels => true,
            :x_label_format => "%m/%d/%y",
         })
          
          graph.add_data({
           :data => projection
             :title => 'Projected',
         })
        
          graph.add_data({
           :data => actual,
             :title => 'Actual',
         })
          
          print graph.burn()
        
        = Description
        
        Produces a graph of temporal scalar data.
        
        = Examples
        
        http://www.germane-software/repositories/public/SVG/test/timeseries.rb
        
        = Notes
        
        The default stylesheet handles upto 10 data sets, if you
        use more you must create your own stylesheet and add the
        additional settings for the extra data sets. You will know
        if you go over 10 data sets as they will have no style and
        be in black.
        
        Unlike the other types of charts, data sets must contain x,y pairs:
        
          ["12:30", 2]          # A data set with 1 point: ("12:30",2)
          ["01:00",2, "14:20",6] # A data set with 2 points: ("01:00",2) and 
                                  #                           ("14:20",6)  
        
        Note that multiple data sets within the same chart can differ in length, 
        and that the data in the datasets needn't be in order; they will be ordered
        by the plot along the X-axis.
        
        The dates must be parseable by ParseDate, but otherwise can be
        any order of magnitude (seconds within the hour, or years)
        
        = See also
        
        * SVG::Graph::Graph
        * SVG::Graph::BarHorizontal
        * SVG::Graph::Bar
        * SVG::Graph::Line
        * SVG::Graph::Pie
        * SVG::Graph::Plot
        
        == Author
        
        Sean E. Russell <serATgermaneHYPHENsoftwareDOTcom>
        
        Copyright 2004 Sean E. Russell
        This software is available under the Ruby license[LICENSE.txt]
"""
    popup_format = x_label_format = '%Y-%m-%d %H:%M:%S'
    __doc_popup_format_ = "The formatting usped for the popups.  See x_label_format"
    __doc_x_label_format_ = "The format string used to format the X axis labels.  See strftime."
    
    timescale_divisions = None
    __doc_timescale_divisions_ = """Use this to set the spacing between dates on the axis.  The value
        must be of the form 
        "\d+ ?(days|weeks|months|years|hours|minutes|seconds)?"

        EG:

        graph.timescale_divisions = "2 weeks"

        will cause the chart to try to divide the X axis up into segments of
        two week periods."""
    
    def add_data(self, data):
        """Add data to the plot.
            d1 = ["12:30", 2]          # A data set with 1 point: ("12:30",2)
            d2 = ["01:00",2, "14:20",6] # A data set with 2 points: ("01:00",2) and 
                                         #                           ("14:20",6)  
            graph.add_data(
              :data => d1,
              :title => 'One'
            )
            graph.add_data(
              :data => d2,
              :title => 'Two'
            )
            
            Note that the data must be in time,value pairs, and that the date format
            may be any date that is parseable by ParseDate."""
        super(Plot, self).add_data(data)
        
    def process_data(self, data):
        super(Plot, self).process_data(data)
        # the date should be in the first element, so parse it out
        data['data'][0] = map(self.parse_date, data['data'][0])

    _min_x_value = svg.charts.plot.Plot.min_x_value    
    def get_min_x_value(self):
        return self._min_x_value
    def set_min_x_value(self, date):
        self._min_x_value = self.parse_date(date)
    min_x_value = property(get_min_x_value, set_min_x_value)
    
    def format(self, x, y):
        return fromtimestamp(x).strftime(self.popup_format)
    
    def get_x_labels(self):
        return map(lambda t: fromtimestamp(t).strftime(self.x_label_format), self.get_x_values())

    def get_x_values(self):
        result = self.get_x_timescale_division_values()
        if result: return result
        return tuple(float_range(*self.x_range()))
            
    def get_x_timescale_division_values(self):
        if not self.timescale_divisions: return
        min, max, scale_division = self.x_range()
        m = re.match('(?P<amount>\d+) ?(?P<division_units>days|weeks|months|years|hours|minutes|seconds)?', self.timescale_divisions)
        # copy amount and division_units into the local namespace
        division_units = m.groupdict()['division_units'] or 'days'
        amount = int(m.groupdict()['amount'])
        if not amount: return
        delta = relativedelta(**{division_units: amount})
        result = tuple(self.get_time_range(min, max, delta))
        return result
    
    def get_time_range(self, start, stop, delta):
        start, stop = map(fromtimestamp, (start, stop))
        current = start
        while current <= stop:
            yield mktime(current.timetuple())
            current += delta
            
    def parse_date(self, date_string):
        return mktime(parse(date_string).timetuple())