#!/usr/bin/env python

#****************************************************************************
# mapdata.py, provides non-GUI base classes for mapping data
#
# FlyWay, a VFR/IFR Route Planner for Pilots
# Copyright (C) 2002, Douglas W. Bell
#
# This is free software; you can redistribute it and/or modify it under the
# terms of the GNU General Public License, Version 2.  This program is
# distributed in the hope that it will be useful, but WITTHOUT ANY WARRANTY.
#*****************************************************************************

from waypoint import Waypoint, Airport, Navaid, Fixpoint
from route import RouteLeg
from units import Angle
import math


class MapData:
    """Calculates and stores mapping info"""
    marginFactor = 1.1
    mapPixels = 500
    minMapSize = 20
    def __init__(self, route):
        self.route = route
        self.routeList = []
        self.airportList = []
        self.navaidList = []
        self.fixList = []
        self.maxLat = 0.0
        self.minLat = 0.0
        self.maxLng = 0.0
        self.minLng = 0.0
        self.calcBounds()
        self.addRouteWp()

    def calcBounds(self):
        """Determine map boundaries for a square map"""
        if self.route.wpList:
            self.maxLat = max([wp.latitudeValue() for wp in self.route.wpList])
            self.minLat = min([wp.latitudeValue() for wp in self.route.wpList])
            self.maxLng = max([abs(wp.longitudeValue()) for wp \
                               in self.route.wpList])
            self.minLng = min([abs(wp.longitudeValue()) for wp \
                               in self.route.wpList])
            lngFactor = (math.cos(self.minLat * math.pi/180) \
                         + math.cos(self.maxLat * math.pi/180)) / 2.0
            xSize = (self.maxLng - self.minLng) * RouteLeg.nmLng * lngFactor
            ySize = (self.maxLat - self.minLat) * RouteLeg.nmLat
            if xSize == 0 and ySize == 0:
                self.maxLat += MapData.minMapSize / (2 * RouteLeg.nmLat)
                self.minLat -= MapData.minMapSize / (2 * RouteLeg.nmLat)
                self.maxLng += MapData.minMapSize \
                               / (2 * RouteLeg.nmLng * lngFactor)
                self.minLng -= MapData.minMapSize \
                               / (2 * RouteLeg.nmLng * lngFactor)
            elif xSize > ySize:     # expand short side to make map square
                delta = (xSize - ySize) / (2 * RouteLeg.nmLat)
                self.maxLat += delta
                self.minLat -= delta
            else:
                delta = (ySize - xSize) / (2 * RouteLeg.nmLng * lngFactor)
                self.maxLng += delta
                self.minLng -= delta
            self.expandBounds(MapData.marginFactor)

    def expandBounds(self, factor):
        """Enlarge boundary by factor on each side"""
        latDelta = (self.maxLat - self.minLat) * (factor - 1)
        self.maxLat += latDelta
        self.minLat -= latDelta
        lngDelta = (self.maxLng - self.minLng) * (factor - 1)
        self.maxLng += lngDelta
        self.minLng -= lngDelta

    def addRouteWp(self):
        """Add waypoints from the route to the map list"""
        self.routeList = [MapItem(wp, self) for wp in self.route.wpList]
        if self.route.legList:
            angList = [Angle(self.route.legList[0].absCourse + 180.0)]
            prevAng = self.route.legList[0].absCourse
            for leg in self.route.legList[1:]:
                newAng = Angle(leg.absCourse + 180.0)
                angList.append((prevAng + newAng) / 2.0)  # average angles
                if abs(prevAng - newAng) > 180:
                    angList[-1] = Angle(angList[-1] + 180.0)
                prevAng = leg.absCourse
            angList.append(prevAng)
            octantList = [int(round(ang / 45.0)) for ang in angList]
            for i in range(len(self.routeList)):
                self.routeList[i].labelOctant = octantList[i]
                if octantList[i] == 8:
                    self.routeList[i].labelOctant = 0

    def addAirports(self):
        """Add additional airports from the database to the map list"""
        self.airportList = [MapItem(wp, self) for wp in \
                            Airport().getAllWaypoints() if self.isOnMap(wp)]

    def addNavaids(self):
        """Add additional navaids from the database to the map list"""
        self.navaidList = [MapItem(wp, self) for wp in \
                           Navaid().getAllWaypoints() if self.isOnMap(wp)]

    def addFixes(self):
        """Add additional fixes from the database to the map list"""
        self.fixList = [MapItem(wp, self) for wp in \
                        Fixpoint().getAllWaypoints() if self.isOnMap(wp)]

    def isOnMap(self, wp):
        """Return 1 if wp is within map bounds"""
        return self.minLat <= wp.latitudeValue() <= self.maxLat \
               and self.minLng <= abs(wp.longitudeValue()) <= self.maxLng


class MapItem:
    """Stores data for an item included on the map"""
    def __init__(self, waypoint, mapData):
        self.waypoint = waypoint
        self.xCoord = MapData.mapPixels - \
                      int((abs(self.waypoint.longitudeValue()) \
                           - mapData.minLng) \
                          / (mapData.maxLng - mapData.minLng) \
                          * MapData.mapPixels)
        self.yCoord = MapData.mapPixels - \
                      int((self.waypoint.latitudeValue() - mapData.minLat) \
                          / (mapData.maxLat - mapData.minLat) \
                          * MapData.mapPixels)
        self.labelOctant = 4        # default label position for route labels