'''
module for loading/saving waypoints
'''
from __future__ import print_function
from builtins import range
from builtins import object

import time, copy
import logging
from . import mavutil
try:
    from google.protobuf import text_format
    import mission_pb2
    HAVE_PROTOBUF = True
except ImportError:
    HAVE_PROTOBUF = False


class MAVWPError(Exception):
    '''MAVLink WP error class'''
    def __init__(self, msg):
        Exception.__init__(self, msg)
        self.message = msg


class MAVWPLoader(object):
    '''MAVLink waypoint loader'''
    def __init__(self, target_system=0, target_component=0):
        self.wpoints = []
        self.target_system = target_system
        self.target_component = target_component
        self.last_change = time.time()

    def count(self):
        '''return number of waypoints'''
        return len(self.wpoints)

    def wp(self, i):
        '''return a waypoint'''
        try:
            the_wp = self.wpoints[i]
        except:
            the_wp = None

        return the_wp

    def wp_is_loiter(self, i):
        '''return true if waypoint is a loiter waypoint'''
        loiter_cmds = [mavutil.mavlink.MAV_CMD_NAV_LOITER_UNLIM,
                mavutil.mavlink.MAV_CMD_NAV_LOITER_TURNS,
                mavutil.mavlink.MAV_CMD_NAV_LOITER_TIME,
                mavutil.mavlink.MAV_CMD_NAV_LOITER_TO_ALT]

        if (self.wpoints[i].command in loiter_cmds):
            return True    

        return False

    def add(self, w, comment=''):
        '''add a waypoint'''
        w = copy.copy(w)
        if comment:
            w.comment = comment
        w.seq = self.count()
        self.wpoints.append(w)
        self.last_change = time.time()

    def insert(self, idx, w, comment=''):
        '''insert a waypoint'''
        if idx >= self.count():
            self.add(w, comment)
            return
        if idx < 0:
            return
        w = copy.copy(w)
        if comment:
            w.comment = comment
        w.seq = idx
        self.wpoints.insert(idx, w)
        self.last_change = time.time()
        self.reindex()

    def reindex(self):
        '''reindex waypoints'''
        for i in range(self.count()):
            w = self.wpoints[i]
            w.seq = i
        self.last_change = time.time()

    def add_latlonalt(self, lat, lon, altitude, terrain_alt=False):
        '''add a point via latitude/longitude/altitude'''
        if terrain_alt:
            frame = mavutil.mavlink.MAV_FRAME_GLOBAL_TERRAIN_ALT
        else:
            frame = mavutil.mavlink.MAV_FRAME_GLOBAL_RELATIVE_ALT
        p = mavutil.mavlink.MAVLink_mission_item_message(self.target_system,
                                                         self.target_component,
                                                         0,
                                                         frame,
                                                         mavutil.mavlink.MAV_CMD_NAV_WAYPOINT,
                                                         0, 0, 0, 0, 0, 0,
                                                         lat, lon, altitude)
        self.add(p)

    def set(self, w, idx):
        '''set a waypoint'''
        w.seq = idx
        if w.seq == self.count():
            return self.add(w)
        if self.count() <= idx:
            raise MAVWPError('adding waypoint at idx=%u past end of list (count=%u)' % (idx, self.count()))
        self.wpoints[idx] = w
        self.last_change = time.time()

    def remove(self, w):
        '''remove a waypoint'''
        self.wpoints.remove(w)
        self.last_change = time.time()
        self.reindex()

    def clear(self):
        '''clear waypoint list'''
        self.wpoints = []
        self.last_change = time.time()

    def _read_waypoints_v100(self, file):
        '''read a version 100 waypoint'''
        cmdmap = {
            2 : mavutil.mavlink.MAV_CMD_NAV_TAKEOFF,
            3 : mavutil.mavlink.MAV_CMD_NAV_RETURN_TO_LAUNCH,
            4 : mavutil.mavlink.MAV_CMD_NAV_LAND,
            24: mavutil.mavlink.MAV_CMD_NAV_TAKEOFF,
            26: mavutil.mavlink.MAV_CMD_NAV_LAND,
            25: mavutil.mavlink.MAV_CMD_NAV_WAYPOINT ,
            27: mavutil.mavlink.MAV_CMD_NAV_LOITER_UNLIM
            }
        comment = ''
        for line in file:
            if line.startswith('#'):
                comment = line[1:].lstrip()
                continue
            line = line.strip()
            if not line:
                continue
            a = line.split()
            if len(a) != 13:
                raise MAVWPError("invalid waypoint line with %u values" % len(a))
            if mavutil.mavlink10():
                fn = mavutil.mavlink.MAVLink_mission_item_message
            else:
                fn = mavutil.mavlink.MAVLink_waypoint_message
            w = fn(self.target_system, self.target_component,
                   int(a[0]),    # seq
                   int(a[1]),    # frame
                   int(a[2]),    # action
                   int(a[7]),    # current
                   int(a[12]),   # autocontinue
                   float(a[5]),  # param1,
                   float(a[6]),  # param2,
                   float(a[3]),  # param3
                   float(a[4]),  # param4
                   float(a[9]),  # x, latitude
                   float(a[8]),  # y, longitude
                   float(a[10])  # z
                   )
            if not w.command in cmdmap:
                raise MAVWPError("Unknown v100 waypoint action %u" % w.command)

            w.command = cmdmap[w.command]
            self.add(w, comment)
            comment = ''

    def _read_waypoints_v110(self, file):
        '''read a version 110 waypoint'''
        comment = ''
        for line in file:
            if line.startswith('#'):
                comment = line[1:].lstrip()
                continue
            line = line.strip()
            if not line:
                continue
            a = line.split()
            if len(a) != 12:
                raise MAVWPError("invalid waypoint line with %u values" % len(a))
            if mavutil.mavlink10():
                fn = mavutil.mavlink.MAVLink_mission_item_message
            else:
                fn = mavutil.mavlink.MAVLink_waypoint_message
            w = fn(self.target_system, self.target_component,
                   int(a[0]),    # seq
                   int(a[2]),    # frame
                   int(a[3]),    # command
                   int(a[1]),    # current
                   int(a[11]),   # autocontinue
                   float(a[4]),  # param1,
                   float(a[5]),  # param2,
                   float(a[6]),  # param3
                   float(a[7]),  # param4
                   float(a[8]),  # x (latitude)
                   float(a[9]),  # y (longitude)
                   float(a[10])  # z (altitude)
                   )
            if w.command == 0 and w.seq == 0 and self.count() == 0:
                # special handling for Mission Planner created home wp
                w.command = mavutil.mavlink.MAV_CMD_NAV_WAYPOINT
            self.add(w, comment)
            comment = ''

    def _read_waypoints_pb_110(self, file):
        if not HAVE_PROTOBUF:
            raise MAVWPError(
                'Cannot read mission file in protobuf format without protobuf '
                'library. Try "easy_install protobuf".')
        explicit_seq = False
        warned_seq = False
        mission = mission_pb2.Mission()
        text_format.Merge(file.read(), mission)
        defaults = mission_pb2.Waypoint()
        # Set defaults (may be overriden in file).
        defaults.current = False
        defaults.autocontinue = True
        defaults.param1 = 0.0
        defaults.param2 = 0.0
        defaults.param3 = 0.0
        defaults.param4 = 0.0
        defaults.x = 0.0
        defaults.y = 0.0
        defaults.z = 0.0
        # Use defaults specified in mission file, if there are any.
        if mission.defaults:
            defaults.MergeFrom(mission.defaults)
        for seq, waypoint in enumerate(mission.waypoint):
            # Consecutive sequence numbers are automatically assigned
            # UNLESS the mission file specifies sequence numbers of
            # its own.
            if waypoint.seq:
                explicit_seq = True
            else:
                if explicit_seq and not warned_seq:
                    logging.warn(
                            'Waypoint file %s: mixes explicit and implicit '
                            'sequence numbers' % (file,))
                    warned_seq = True
            # The first command has current=True, the rest have current=False.
            if seq > 0:
                current = defaults.current
            else:
                current = True
            w = mavutil.mavlink.MAVLink_mission_item_message(
                self.target_system, self.target_component,
                   waypoint.seq or seq,
                   waypoint.frame,
                   waypoint.command,
                   waypoint.current or current,
                   waypoint.autocontinue or defaults.autocontinue,
                   waypoint.param1 or defaults.param1,
                   waypoint.param2 or defaults.param2,
                   waypoint.param3 or defaults.param3,
                   waypoint.param4 or defaults.param4,
                   waypoint.x or defaults.x,
                   waypoint.y or defaults.y,
                   waypoint.z or defaults.z)
            self.add(w)

    def load(self, filename):
        '''load waypoints from a file.
        returns number of waypoints loaded'''
        f = open(filename, mode='r')
        version_line = f.readline().strip()
        if version_line == "QGC WPL 100":
            readfn = self._read_waypoints_v100
        elif version_line == "QGC WPL 110":
            readfn = self._read_waypoints_v110
        elif version_line == "QGC WPL PB 110":
            readfn = self._read_waypoints_pb_110
        else:
            f.close()
            raise MAVWPError("Unsupported waypoint format '%s'" % version_line)

        self.clear()
        readfn(f)
        f.close()

        return len(self.wpoints)

    def save_as_pb(self, filename):
        mission = mission_pb2.Mission()
        for w in self.wpoints:
            waypoint = mission.waypoint.add()
            waypoint.command = w.command
            waypoint.frame = w.frame
            waypoint.seq = w.seq
            waypoint.current = w.current
            waypoint.autocontinue = w.autocontinue
            waypoint.param1 = w.param1
            waypoint.param2 = w.param2
            waypoint.param3 = w.param3
            waypoint.param4 = w.param4
            waypoint.x = w.x
            waypoint.y = w.y
            waypoint.z = w.z
        with open(filename, 'w') as f:
            f.write('QGC WPL PB 110\n')
            f.write(text_format.MessageToString(mission))

    def save(self, filename):
        '''save waypoints to a file'''
        f = open(filename, mode='w')
        f.write("QGC WPL 110\n")
        for w in self.wpoints:
            if getattr(w, 'comment', None):
                f.write("# %s\n" % w.comment)
            f.write("%u\t%u\t%u\t%u\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%u\n" % (
                w.seq, w.current, w.frame, w.command,
                w.param1, w.param2, w.param3, w.param4,
                w.x, w.y, w.z, w.autocontinue))
        f.close()

    def is_location_command(self, cmd):
        '''see if cmd is a MAV_CMD with a latitide/longitude.
        We check if it has Latitude and Longitude params in the right indexes'''
        mav_cmd = mavutil.mavlink.enums['MAV_CMD']
        if not cmd in mav_cmd:
            return False
        if not mav_cmd[cmd].param.get(5,'').startswith('Latitude'):
            return False
        if not mav_cmd[cmd].param.get(6,'').startswith('Longitude'):
            return False
        return True


    def view_indexes(self, done=None):
        '''return a list waypoint indexes in view order'''
        ret = []
        if done is None:
            done = set()
        idx = 0

        # find first point not done yet
        while idx < self.count():
            if not idx in done:
                break
            idx += 1
            
        while idx < self.count():
            w = self.wp(idx)
            if idx in done:
                if w.x != 0 or w.y != 0:
                    ret.append(idx)
                break
            done.add(idx)
            if w.command == mavutil.mavlink.MAV_CMD_DO_JUMP:
                idx = int(w.param1)
                w = self.wp(idx)
                if w.x != 0 or w.y != 0:
                    ret.append(idx)
                continue
            if (w.x != 0 or w.y != 0) and self.is_location_command(w.command):
                ret.append(idx)
            idx += 1
        return ret

    def polygon(self, done=None):
        '''return a polygon for the waypoints'''
        indexes = self.view_indexes(done)
        points = []
        for idx in indexes:
            w = self.wp(idx)
            points.append((w.x, w.y))
        return points

    def polygon_list(self):
        '''return a list of polygons for the waypoints'''
        done = set()
        ret = []
        while len(done) != self.count():
            p = self.polygon(done)
            if len(p) > 0:
                ret.append(p)
        return ret

    def view_list(self):
        '''return a list of polygon indexes lists for the waypoints'''
        done = set()
        ret = []
        while len(done) != self.count():
            p = self.view_indexes(done)
            if len(p) > 0:
                ret.append(p)
        return ret

class MAVRallyError(Exception):
    '''MAVLink rally point error class'''
    def __init__(self, msg):
        Exception.__init__(self, msg)
        self.message = msg

class MAVRallyLoader(object):
    '''MAVLink Rally points and Rally Land ponts loader'''
    def __init__(self, target_system=0, target_component=0):
        self.rally_points = []
        self.target_system = target_system
        self.target_component = target_component
        self.last_change = time.time()

    def rally_count(self):
        '''return number of rally points'''
        return len(self.rally_points)

    def rally_point(self, i):
        '''return rally point i'''
        return self.rally_points[i]

    def reindex(self):
        '''reset counters and indexes'''
        for i in range(self.rally_count()):
            self.rally_points[i].count = self.rally_count()
            self.rally_points[i].idx = i
        self.last_change = time.time()
            
    def append_rally_point(self, p):
        '''add rallypoint to end of list'''
        if (self.rally_count() > 9):
           print("Can't have more than 10 rally points, not adding.")
           return

        self.rally_points.append(p)
        self.reindex()

    def create_and_append_rally_point(self, lat, lon, alt, break_alt, land_dir, flags):
        '''add a point via latitude/longitude'''
        p = mavutil.mavlink.MAVLink_rally_point_message(self.target_system, self.target_component,
                                                        self.rally_count(), 0, lat, lon, alt, break_alt, land_dir, flags)
        self.append_rally_point(p)

    def clear(self):
        '''clear all point lists (rally and rally_land)'''
        self.rally_points = []
        self.last_change = time.time()

    def remove(self, i):
        '''remove a rally point'''
        if i < 1 or i > self.rally_count():
            print("Invalid rally point number %u" % i)
        self.rally_points.pop(i-1)
        self.reindex()

    def move(self, i, lat, lng, change_time=True):
        '''move a rally point'''
        if i < 1 or i > self.rally_count():
            print("Invalid rally point number %u" % i)
        self.rally_points[i-1].lat = int(lat*1e7)
        self.rally_points[i-1].lng = int(lng*1e7)
        if change_time:
            self.last_change = time.time()

    def set_alt(self, i, alt, break_alt=None, change_time=True):
        '''set rally point altitude(s)'''
        if i < 1 or i > self.rally_count():
            print("Inavlid rally point number %u" % i)
            return
        self.rally_points[i-1].alt = int(alt)
        if (break_alt != None):
            self.rally_points[i-1].break_alt = break_alt
        if change_time:
            self.last_change = time.time()

    def load(self, filename):
        '''load rally and rally_land points from a file.
         returns number of points loaded'''
        f = open(filename, mode='r')
        self.clear()
        for line in f:
            if line.startswith('#'):
                continue
            line = line.strip()
            if not line:
                continue
            a = line.split()
            if len(a) != 7:
                raise MAVRallyError("invalid rally file line: %s" % line)

            if (a[0].lower() == "rally"):
                self.create_and_append_rally_point(float(a[1]) * 1e7, float(a[2]) * 1e7,
                                                   float(a[3]), float(a[4]), float(a[5]) * 100.0, int(a[6]))
        f.close()
        return len(self.rally_points)

    def save(self, filename):
        '''save fence points to a file'''
        f = open(filename, mode='w')
        for p in self.rally_points:
            f.write("RALLY %f\t%f\t%f\t%f\t%f\t%d\n" % (p.lat * 1e-7, p.lng * 1e-7, p.alt,
                                                        p.break_alt, p.land_dir, p.flags))
        f.close()

class MAVFenceError(Exception):
        '''MAVLink fence error class'''
        def __init__(self, msg):
            Exception.__init__(self, msg)
            self.message = msg

class MAVFenceLoader(object):
    '''MAVLink geo-fence loader'''
    def __init__(self, target_system=0, target_component=0):
        self.points = []
        self.target_system = target_system
        self.target_component = target_component
        self.last_change = time.time()

    def count(self):
        '''return number of points'''
        return len(self.points)

    def point(self, i):
        '''return a point'''
        return self.points[i]

    def add(self, p):
        '''add a point'''
        self.points.append(p)
        self.reindex()

    def reindex(self):
        '''reindex waypoints'''
        for i in range(self.count()):
            w = self.points[i]
            w.idx = i
            w.count = self.count()
            w.target_system = self.target_system
            w.target_component = self.target_component
        self.last_change = time.time()

    def add_latlon(self, lat, lon):
        '''add a point via latitude/longitude'''
        p = mavutil.mavlink.MAVLink_fence_point_message(self.target_system, self.target_component,
                                                        self.count(), 0, lat, lon)
        self.add(p)

    def clear(self):
        '''clear point list'''
        self.points = []
        self.last_change = time.time()

    def load(self, filename):
        '''load points from a file.
        returns number of points loaded'''
        f = open(filename, mode='r')
        self.clear()
        for line in f:
            if line.startswith('#'):
                continue
            line = line.strip()
            if not line:
                continue
            a = line.split()
            if len(a) != 2:
                raise MAVFenceError("invalid fence point line: %s" % line)
            self.add_latlon(float(a[0]), float(a[1]))
        f.close()
        return len(self.points)

    def save(self, filename):
        '''save fence points to a file'''
        f = open(filename, mode='w')
        for p in self.points:
            f.write("%f\t%f\n" % (p.lat, p.lng))
        f.close()

    def move(self, i, lat, lng, change_time=True):
        '''move a fence point'''
        if i < 0 or i >= self.count():
            print("Invalid fence point number %u" % i)
        self.points[i].lat = lat
        self.points[i].lng = lng
        # ensure we close the polygon
        if i == 1:
                self.points[self.count()-1].lat = lat
                self.points[self.count()-1].lng = lng
        if i == self.count() - 1:
                self.points[1].lat = lat
                self.points[1].lng = lng
        if change_time:
            self.last_change = time.time()

    def remove(self, i, change_time=True):
        '''remove a fence point'''
        if i < 0 or i >= self.count():
            print("Invalid fence point number %u" % i)
        self.points.pop(i)
         # ensure we close the polygon
        if i == 1:
                self.points[self.count()-1].lat = self.points[1].lat
                self.points[self.count()-1].lng = self.points[1].lng
        if i == self.count():
                self.points[1].lat = self.points[self.count()-1].lat
                self.points[1].lng = self.points[self.count()-1].lng
        if change_time:
            self.last_change = time.time()

    def polygon(self):
            '''return a polygon for the fence'''
            points = []
            for fp in self.points[1:]:
                    points.append((fp.lat, fp.lng))
            return points
