#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright (C) 2012  Étienne Loks  <etienne.loks_AT_peacefrogsDOTnet>
#

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# See the file COPYING for details.

"""
Routing management
"""

import os
import re
import shutil
import tempfile
import json
from bs4 import BeautifulSoup
from subprocess import Popen, PIPE
from django.contrib.gis.gdal import DataSource
from django.contrib.gis.gdal.error import GDALException

from django.conf import settings


class Router:
    def route(self, lon1, lat1, lon2, lat2, transport='foot'):
        '''
        Get a list of geojson polylines
        '''
        return []


class RoutinoRouter(Router):
    re_desc = [re.compile("<tr class='n'>"), re.compile("<tr class='s'>"),
               re.compile("<tr class='t'>")]

    def route(self, lon1, lat1, lon2, lat2, steps=[], transport='foot',
              speed=None):
        '''
        Get a list of geojson polylines and route description
        '''
        language = settings.LANGUAGE_CODE.split('-')[0]
        args = [settings.CHIMERE_ROUTING_ENGINE['PATH'],
                "--dir=%s" % settings.CHIMERE_ROUTING_ENGINE['DB_PATH'],
                "--transport=%s" % transport,
                "--language=%s" % language,
                "--shortest",
                "--output-html",
                "--output-gpx-track",
                "--lat1=%0.15f" % lat1,
                "--lon1=%0.15f" % lon1,
                ]
        if speed:
            args += [
                "--speed-%s=%s" % (highway, str(speed))
                for highway in (
                    'motorway', 'trunk', 'primary', 'secondary', 'tertiary',
                    'unclassified', 'residential', 'service', 'track',
                    'cycleway', 'path', 'steps')]
        lonlat_index = 1
        for lon, lat in steps:
            lonlat_index += 1
            args += ["--lat%d=%0.15f" % (lonlat_index, lat),
                     "--lon%d=%0.15f" % (lonlat_index, lon)]
        lonlat_index += 1
        args += ["--lat%d=%0.15f" % (lonlat_index, lat2),
                 "--lon%d=%0.15f" % (lonlat_index, lon2)]
        tmp_dir = tempfile.mkdtemp(prefix='chimere_') + os.sep
        p = Popen(args, stdout=PIPE, cwd=tmp_dir)
        p.communicate()
        try:
            ds = DataSource(tmp_dir + 'shortest-track.gpx')
        except GDALException:
            return [], None, None
        if not ds:
            return [], None, None
        layer = ds[0]
        trk_layer = None
        for layer in ds:
            if layer.name == 'tracks':
                trk_layer = layer
                break
        multilines = trk_layer.get_geoms()
        res = []
        jsonencoder = json.JSONEncoder()
        jsondecoder = json.JSONDecoder()
        for multiline in multilines:
            res += [
                jsonencoder.encode(
                    {"type": "Feature",
                     "geometry": jsondecoder.decode(geom.geojson)})
                for geom in multiline]
        desc = []
        # only keeping interessant lines of the desc
        for line in open(tmp_dir + 'shortest.html').readlines():
            if [True for r in self.re_desc if r.match(line)]:
                desc.append(BeautifulSoup(line).prettify())
        total = self.webify(desc[-1])
        desc = desc[1:-2]
        # very fragile piece of code but only break the numerotation
        number_tpl = '<tr class="n"><span class="number">%d.</span>'
        new_desc = []
        for idx, d in enumerate(desc):
            for tag in ("<html>", "</html>", "<body>", "</body>"):
                d = re.sub(tag, "", d)
            if idx % 2:
                new_desc.append(
                    re.sub('<tr class="n">',
                           number_tpl % (int(idx / 2) + 1),
                           d))
            else:
                new_desc.append(d)
        desc = new_desc
        desc = self.webify(BeautifulSoup('\n'.join(desc)).prettify())
        desc = re.sub("  \[", "", desc)
        desc = re.sub("  \]", "", desc)
        shutil.rmtree(tmp_dir)
        return res, desc, total

    @staticmethod
    def webify(lbl):
        lbl = re.sub("<td", "<span", lbl)
        lbl = re.sub("</td>", "</span>", lbl)
        lbl = re.sub("</tr>", "</div>", lbl)
        lbl = re.sub("<tr", "<div", lbl)
        return lbl

router = None
if hasattr(settings, 'CHIMERE_ROUTING_ENGINE') and \
   settings.CHIMERE_ROUTING_ENGINE['ENGINE'] == 'routino':
    router = RoutinoRouter()