#!/usr/bin/python3
import json
import time
import xml.etree.ElementTree

import requests
from requests.auth import HTTPDigestAuth


def PTZData(d, root="PTZData"):
    op = lambda tag: '<' + tag + '>'
    cl = lambda tag: '</' + tag + '>\n'
    ml = lambda v, xml: xml + op(key) + str(v) + cl(key)
    xml = op(root) + '\n' if root else ""
    if isinstance(d, list):
        for v in d:
            xml = ml(v, xml)
    else:
        for key, vl in d.items():
            if isinstance(vl, list):
                for v in vl:
                    xml = ml(v, xml)
            if isinstance(vl, dict):
                xml = ml('\n' + PTZData(vl, None), xml)
            if not isinstance(vl, (list, dict)):
                xml = ml(vl, xml)
    xml += cl(root) if root else ""
    return xml

def etree_to_list(t):
    d = []
    k = t.tag.split('}')[-1]
    v = list(map(etree_to_dict, t.getchildren()))
    if len(v) == 1:
        v = v[0]
    elif v and not isinstance(v[0], dict):
        v_ = {}
        for kv in v:
            for key, value in kv.items():
                if isinstance(value, str) and (value.isdigit() or value[1:].isdigit()):
                    value = int(value)
                v_[key] = value
        v = v_
    return v

def etree_to_dict(t):
    d = {}
    k = t.tag.split('}')[-1]
    v = list(map(etree_to_dict, t.getchildren()))
    if len(v) == 1:
        v = v[0]
    #elif v and not isinstance(v[0], dict):
    else:
        v_ = {}
        for kv in v:
            for key, value in kv.items():
                if isinstance(value, str) and (value.isdigit() or value[1:].isdigit()):
                    value = int(value)
                v_[key] = value
        v = v_
    d = {k: v}
    #d.update(('@' + k, v) for k, v in t.attrib.items())
    if not v:
        d[k] = t.text
    elif t.text.strip():
        d['text'] = t.text
    return d

def is_close_enough(a, b):
    return abs(a['elevation'] - b['elevation']) < 2 \
        and abs(a['absoluteZoom'] - b['absoluteZoom']) < 2 \
        and abs(a['azimuth'] - b['azimuth']) < 2


class Camera:
    STOP = {'pan': 0, 'tilt': 0, 'zoom': 0}
    LEFT = {'pan': -1, 'tilt': 0, 'zoom': 0}
    RIGHT = {'pan': 1, 'tilt': 0, 'zoom': 0}
    UP = {'pan': 0, 'tilt': 1, 'zoom': 0}
    DOWN = {'pan': 0, 'tilt': -1, 'zoom': 0}
    LEFT_UP = {'pan': -1, 'tilt': 1, 'zoom': 0}
    LEFT_DOWN = {'pan': -1, 'tilt': -1, 'zoom': 0}
    RIGHT_UP = {'pan': 1, 'tilt': 1, 'zoom': 0}
    RIGHT_DOWN = {'pan': 1, 'tilt': -1, 'zoom': 0}

    IN = {'pan': 1, 'tilt': 0, 'zoom': 1}
    OUT = {'pan': 1, 'tilt': 0, 'zoom': -1}

    abort = False
    sequence_time = 0
    segment_times = {}
    next_target = None
    last_position = {}

    def __init__(self, ip='192.168.1.64', username='admin', password='admin', channel=1):
        self.ip = ip
        self.username = username
        self.password = password
        self.channel = channel
        self.auth = HTTPDigestAuth(self.username, self.password)

    def url(self, method):
        return 'http://{}/ISAPI/PTZCtrl/channels/{}/{}'.format(self.ip, self.channel, method)

    def parse_xml(self, data):
        return etree_to_dict(xml.etree.ElementTree.fromstring(data))

    def status(self):
        s = self.parse_xml(self.get('status'))
        if 'PTZStatus' in s:
            self.last_position = s['PTZStatus']['AbsoluteHigh']
            return self.last_position
        return {}

    def get(self, method):
        return requests.get(self.url(method), auth=self.auth).text

    def put(self, method, data):
        if isinstance(data, dict):
            data = PTZData(data)
        return requests.put(self.url(method), data=data, auth=self.auth).text

    def momentary(self, cmd, duration=None):
        if duration:
            cmd['Momentary'] = {
                'duration': int(duration * 1000)
            }
        r = self.put('momentary', cmd)
        if '<statusCode>1</statusCode>' not in r:
            print(r)

    def continuous(self, cmd, duration=None):
        r = self.put('continuous', cmd)
        if '<statusCode>1</statusCode>' not in r:
            print(r)
        elif duration:
            time.sleep(duration)
            self.continuous(self.STOP)

    def set_preset(self, id, name):
        data = PTZData({
            'id': str(id),
            'presetName': name
        }, 'PTZPreset')
        r = self.put('presets/%s' % id, data)
        if '<statusCode>1</statusCode>' not in r:
            print(r)

    def set_presets(self, presets):
        for preset in presets:
            self.absolute(**preset['position'])
            time.sleep(5)
            self.goto(**preset['position'])
            self.set_preset(preset['id'], preset['name'])
            time.sleep(1)
        print('presets loaded')

    def sequence(self, steps=[], speed=12, goto_first=True):
        self.sequence_start = 0
        if goto_first:
            #self.goto_preset(steps[0], pan=100, tilt=100, zoom=100)
            first = steps[0]
            if isinstance(first, dict):
                if 'seqid' in first and first['seqid'] not in self.segment_times:
                    self.segment_times[first['seqid']] = 0
                first = first['preset']
            self.fast_preset(first, True)
            #self.goto_preset(first, pan=speed, tilt=speed)
            if self.abort:
                return
            time.sleep(3)
            steps = steps[1:]
        self.sequence_start = t0 = time.time()
        for step in steps:
            self.next_target = step
            segment_t0 = time.time()
            if self.abort:
                return
            if isinstance(step, dict):
                if 'fast' in step or ('speed' in step and step['speed'] > 100):
                    self.fast_preset(step.get('fast', step.get('preset')), True)
                else:
                    if 'preset' in step:
                        kwargs = {
                            'pan': step['speed'],
                            'tilt': step['speed'],
                        }
                        if step.get('zoom'):
                            kwargs['zoom'] = step['zoom']
                        if 'zoom_last' in step:
                            kwargs['zoom_last'] = step['zoom_last']
                        self.goto_preset(step['preset'], **kwargs)
                if 'sleep' in step:
                    if self.abort:
                        return
                    time.sleep(float(step['sleep']))
            else:
                self.goto_preset(step, pan=speed, tilt=speed)

            segment_time = time.time() - segment_t0
            if isinstance(step, dict) and 'seqid' in step:
                self.segment_times[step['seqid']] = segment_time
        self.sequence_time = time.time() - t0
        self.next_target = None

    def fast_preset(self, id, wait=False):
        self.put('presets/%s/goto' % id, None)
        if wait:
            preset = self.get_preset(id)['position']
            last = self.status()

            while not is_close_enough(last, preset):
                time.sleep(0.1)
                last = self.status()

    def goto_preset(self, id, pan, tilt, zoom=1, zoom_last=False):
        if self.abort:
            return
        presets = self.get_presets(True)
        if isinstance(id, str):
            preset = [p for p in presets if p['name'] == id]
            if not preset:
                raise Exception('unknown preset %s' % id)
            id = preset[0]['id']
        else:
            preset = [p for p in presets if p['id'] == id]
            if not preset:
                raise Exception('unknown preset %s' % id)
        preset = preset[0]
        i = preset['position']
        if i['elevation'] < 0:
            i['elevation'] -= 1
            i['azimuth'] += 1
        print('goto preset', id, i['elevation'], i['azimuth'], i['absoluteZoom'])
        return self.goto(i['elevation'], i['azimuth'], i['absoluteZoom'],
                         pan=pan, tilt=tilt, zoom=zoom, zoom_last=zoom_last)

    def goto(self, elevation, azimuth, absoluteZoom, speed=1, pan=None, tilt=None, zoom=None, zoom_last=False):
        t0 = time.time()
        start = self.status()
        target = {'elevation': elevation, 'azimuth': azimuth, 'absoluteZoom': absoluteZoom}
        print('start:', start, 'target:', target)

        if zoom_last:
            goto_last = {
                'speed': speed,
                'pan': pan,
                'tilt': tilt,
                'zoom': zoom,
            }
            goto_last.update(target)
            target['absoluteZoom'] = start['absoluteZoom']

        def get_delta():
            current = self.status()
            delta = {}
            for key in current:
                delta[key] = target[key] - current[key]
            return current, delta

        current, delta = get_delta()

        if pan is None:
            pan = speed
        if tilt is None:
            tilt = speed
        if zoom is None:
            zoom = 1
        if delta['elevation'] > 0:
            tilt = -tilt
        if delta['azimuth'] < 0:
            pan = -pan
        if delta['absoluteZoom'] < 0:
            zoom = -zoom
        if pan and not delta['azimuth']:
            pan = 0
        if tilt and not delta['elevation']:
            tilt = 0
        if zoom and not delta['absoluteZoom']:
            zoom = 0

        move = {'pan': pan, 'tilt': tilt, 'zoom': zoom}
        direction = {k: v >= 0 for k, v in delta.items()}
        print(move, direction)
        self.continuous(move)
        n = 0
        while sum(map(abs, move.values())):
            n += 1
            #print(current, delta, move)
            current, delta = get_delta()
            changed = False
            if 'azimuth' in delta and 'azimuth' in direction:
                if pan and (not delta['azimuth'] or (delta['azimuth'] >= 0) != direction['azimuth']):
                    pan = 0
                    changed = True
            else:
                print('why no azimuth? delta: %s direction: %s' % (delta, direction))
            '''
            if pan > 0:
                pan = min(pan, delta['azimuth'])
                change = True
            elif pan < 0 and delta['azimuth'] < 0:
                pan = max(pan, delta['azimuth'])
                changed = True
            '''
            if tilt and (not delta['elevation'] or (delta['elevation'] >= 0) != direction['elevation']):
                tilt = 0
                changed = True
            '''
            if tilt > 0:
                tilt = min(tilt, delta['elevation'])
                change = True
            elif tilt < 0 and delta['elevation'] < 0:
                tilt = max(tilt, delta['elevation'])
                changed = True
            '''
            if zoom and (not delta['absoluteZoom'] or (delta['absoluteZoom'] >= 0) != direction['absoluteZoom']):
                zoom = 0
                changed = True

            if changed or not n % 500:
                print('update move', move, current)
                move = {'pan': pan, 'tilt': tilt, 'zoom': zoom}
                self.continuous(self.STOP)
                self.continuous(move)
            if sum(map(abs, move.values())) and not self.abort:
                time.sleep(0.1)
            if self.abort:
                self.continuous(self.STOP)
                return
        self.continuous(self.STOP)
        print(time.time() - t0)
        if zoom_last:
            return self.goto(**goto_last)
        else:
            return get_delta()

    def get_preset(self, id):
        presets = self.get_presets(True)
        if isinstance(id, str):
            preset = [p for p in presets if p['name'] == id]
            if not preset:
                raise Exception('unknown preset %s' % id)
            id = preset[0]['id']
        else:
            preset = [p for p in presets if p['id'] == id]
            if not preset:
                raise Exception('unknown preset %s' % id)
        preset = preset[0]
        return preset

    def absolute(self, elevation, azimuth, absoluteZoom):
        cmd = {
            'AbsoluteHigh': {
                'elevation': elevation,
                'azimuth': azimuth,
                'absoluteZoom': absoluteZoom
            }
        }
        r = self.put('absolute', cmd)
        if '<statusCode>1</statusCode>' not in r:
            print(r)
            return False
        return True

    def get_presets_xml(self):
        return self.get('presets')

    def get_presets(self, details=False):
        system_presets = list(range(33, 47)) + list(range(90, 106))
        presets = etree_to_list(xml.etree.ElementTree.fromstring(self.get('presets')))
        presets = [k['PTZPreset'] for k in presets if k['PTZPreset']['id'] not in system_presets]
        for preset in presets:
            del preset['enabled']
            if not details:
                del preset['AbsoluteHigh']
            else:
                preset['position'] = preset.pop('AbsoluteHigh')
            preset['name'] = preset.pop('presetName')
        return presets